beaglebone: TT3201 CAN Bus Cape MCP2515 fixes #7

dwery · 2013-05-23T19:01:31Z

Signed-off-by: Alessandro Zummo [email protected]

Since we currently can't export the IIO channels from the ADCs this patch exposes an sysfs entry to read a respective channel. Signed-off-by: Matt Ranostay <[email protected]>

Added an example usage of the IIO exporter for an current sensor reading. Scale factor works with INA169 current sensor at 10k load. Signed-off-by: Matt Ranostay <[email protected]>

Gave an example on using the kernel-command-line override slot options for capemanager. Signed-off-by: Matt Ranostay <[email protected]>

Added a simple MODULE_PARM_DESC for the extra_override option Signed-off-by: Matt Ranostay <[email protected]>

Add support for a DS1307 RTC prototype cape with level logic shifted output. Some applications need an early RTC value and this achieves this. Signed-off-by: Matt Ranostay <[email protected]>

Catch corner case of division by zero when passing in vsense-scale property from the device tree. Signed-off-by: Matt Ranostay <[email protected]>

Signed-off-by: Koen Kooi <[email protected]>

Allow multiple ADC entries. DT bindinds are extended so you can do: vsense-name = "AIN1", "AIN3"; vsense-scale = <100 100>; Signed-off-by: Pantelis Antoniou <[email protected]>

Signed-off-by: Pantelis Antoniou <[email protected]>

…king) modes the default

…th (maximum width in pixels) ti,max_pixelclock (maximum allowable pixel clock for the device) also added some extra debugging enabled with drm debug to help understand why modes are being selected or rejected.

Signed-off-by: Koen Kooi <[email protected]>

It's too difficult for now to see how to test those. Temporarily take it out.

Not working yet, since more changes needed, but it's a start.

…messages when deciding if a mode is supported or not

…ntroller, otherwise prune the mode. Also adjust the timing values to behave as the TRM indicates with 0 representing 1 in some cases.

Signed-off-by: Koen Kooi <[email protected]>

Support for the Signal 11 MRF24J40 BeagleBone Cape.

am335x-bone-common.dtsi has removed the pinmux settings for SPI1. Add them to the MRF24J40 cape dts fragment Signed-off-by: Alan Ott <[email protected]>

Signed-off-by: Alan Ott <[email protected]>

Signed-off-by: Koen Kooi <[email protected]>

Allow capes to be disabled on the kernel command line. Signed-off-by: Pantelis Antoniou <[email protected]>

Things like the boot switch are on the LCD data pins. Allows us to change pinmuxing on runtime.

Doesn't work ofcourse due to conflict with the HDMI. Conflicts: firmware/Makefile

Signed-off-by: Koen Kooi <[email protected]>

All tests should pass with and without JIT. Example output: test_bpf: #0 TAX 35 16 16 PASS test_bpf: #1 TXA 7 7 7 PASS test_bpf: #2 ADD_SUB_MUL_K 10 PASS test_bpf: #3 DIV_KX 33 PASS test_bpf: #4 AND_OR_LSH_K 10 10 PASS test_bpf: #5 LD_IND 8 8 8 PASS test_bpf: #6 LD_ABS 8 8 8 PASS test_bpf: #7 LD_ABS_LL 13 14 PASS test_bpf: #8 LD_IND_LL 12 12 12 PASS test_bpf: #9 LD_ABS_NET 10 12 PASS test_bpf: torvalds#10 LD_IND_NET 11 12 12 PASS ... Numbers are times in nsec per filter for given input data. Signed-off-by: Alexei Starovoitov <[email protected]> Signed-off-by: David S. Miller <[email protected]>

This patch tries to fix this crash: #5 [ffff88003c1cd690] do_invalid_op at ffffffff810166d5 #6 [ffff88003c1cd730] invalid_op at ffffffff8159b2de [exception RIP: ocfs2_direct_IO_get_blocks+359] RIP: ffffffffa05dfa27 RSP: ffff88003c1cd7e8 RFLAGS: 00010202 RAX: 0000000000000000 RBX: ffff88003c1cdaa8 RCX: 0000000000000000 RDX: 000000000000000c RSI: ffff880027a95000 RDI: ffff88003c79b540 RBP: ffff88003c1cd858 R8: 0000000000000000 R9: ffffffff815f6ba0 R10: 00000000000001c9 R11: 00000000000001c9 R12: ffff88002d271500 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000001000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #7 [ffff88003c1cd860] do_direct_IO at ffffffff811cd31b #8 [ffff88003c1cd950] direct_IO_iovec at ffffffff811cde9c #9 [ffff88003c1cd9b0] do_blockdev_direct_IO at ffffffff811ce764 torvalds#10 [ffff88003c1cdb80] __blockdev_direct_IO at ffffffff811ce7cc torvalds#11 [ffff88003c1cdbb0] ocfs2_direct_IO at ffffffffa05df756 [ocfs2] torvalds#12 [ffff88003c1cdbe0] generic_file_direct_write_iter at ffffffff8112f935 torvalds#13 [ffff88003c1cdc40] ocfs2_file_write_iter at ffffffffa0600ccc [ocfs2] torvalds#14 [ffff88003c1cdd50] do_aio_write at ffffffff8119126c torvalds#15 [ffff88003c1cddc0] aio_rw_vect_retry at ffffffff811d9bb4 torvalds#16 [ffff88003c1cddf0] aio_run_iocb at ffffffff811db880 torvalds#17 [ffff88003c1cde30] io_submit_one at ffffffff811dc238 torvalds#18 [ffff88003c1cde80] do_io_submit at ffffffff811dc437 torvalds#19 [ffff88003c1cdf70] sys_io_submit at ffffffff811dc530 torvalds#20 [ffff88003c1cdf80] system_call_fastpath at ffffffff8159a159 It crashes at BUG_ON(create && (ext_flags & OCFS2_EXT_REFCOUNTED)); in ocfs2_direct_IO_get_blocks. ocfs2_direct_IO_get_blocks is expecting the OCFS2_EXT_REFCOUNTED be removed in ocfs2_prepare_inode_for_write() if it was there. But no cluster lock is taken during the time before (or inside) ocfs2_prepare_inode_for_write() and after ocfs2_direct_IO_get_blocks(). It can happen in this case: Node A(which crashes) Node B ------------------------ --------------------------- ocfs2_file_aio_write ocfs2_prepare_inode_for_write ocfs2_inode_lock ... ocfs2_inode_unlock #no refcount found .... ocfs2_reflink ocfs2_inode_lock ... ocfs2_inode_unlock #now, refcount flag set on extent ... flush change to disk ocfs2_direct_IO_get_blocks ocfs2_get_clusters #extent map miss #buffer_head miss read extents from disk found refcount flag on extent crash.. Fix: Take rw_lock in ocfs2_reflink path Signed-off-by: Wengang Wang <[email protected]> Reviewed-by: Mark Fasheh <[email protected]> Cc: Joel Becker <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>

Writing to either "cpuset.cpus" or "cpuset.mems" file flushes cpuset_hotplug_work so that cpu or memory hotunplug doesn't end up migrating tasks off a cpuset after new resources are added to it. As cpuset_hotplug_work calls into cgroup core via cgroup_transfer_tasks(), this flushing adds the dependency to cgroup core locking from cpuset_write_resmak(). This used to be okay because cgroup interface files were protected by a different mutex; however, 8353da1 ("cgroup: remove cgroup_tree_mutex") simplified the cgroup core locking and this dependency became a deadlock hazard - cgroup file removal performed under cgroup core lock tries to drain on-going file operation which is trying to flush cpuset_hotplug_work blocked on the same cgroup core lock. The locking simplification was done because kernfs added an a lot easier way to deal with circular dependencies involving kernfs active protection. Let's use the same strategy in cpuset and break active protection in cpuset_write_resmask(). While it isn't the prettiest, this is a very rare, likely unique, situation which also goes away on the unified hierarchy. The commands to trigger the deadlock warning without the patch and the lockdep output follow. localhost:/ # mount -t cgroup -o cpuset xxx /cpuset localhost:/ # mkdir /cpuset/tmp localhost:/ # echo 1 > /cpuset/tmp/cpuset.cpus localhost:/ # echo 0 > cpuset/tmp/cpuset.mems localhost:/ # echo $$ > /cpuset/tmp/tasks localhost:/ # echo 0 > /sys/devices/system/cpu/cpu1/online ====================================================== [ INFO: possible circular locking dependency detected ] 3.16.0-rc1-0.1-default+ #7 Not tainted ------------------------------------------------------- kworker/1:0/32649 is trying to acquire lock: (cgroup_mutex){+.+.+.}, at: [<ffffffff8110e3d7>] cgroup_transfer_tasks+0x37/0x150 but task is already holding lock: (cpuset_hotplug_work){+.+...}, at: [<ffffffff81085412>] process_one_work+0x192/0x520 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (cpuset_hotplug_work){+.+...}: ... -> #1 (s_active#175){++++.+}: ... -> #0 (cgroup_mutex){+.+.+.}: ... other info that might help us debug this: Chain exists of: cgroup_mutex --> s_active#175 --> cpuset_hotplug_work Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(cpuset_hotplug_work); lock(s_active#175); lock(cpuset_hotplug_work); lock(cgroup_mutex); *** DEADLOCK *** 2 locks held by kworker/1:0/32649: #0: ("events"){.+.+.+}, at: [<ffffffff81085412>] process_one_work+0x192/0x520 #1: (cpuset_hotplug_work){+.+...}, at: [<ffffffff81085412>] process_one_work+0x192/0x520 stack backtrace: CPU: 1 PID: 32649 Comm: kworker/1:0 Not tainted 3.16.0-rc1-0.1-default+ #7 ... Call Trace: [<ffffffff815a5f78>] dump_stack+0x72/0x8a [<ffffffff810c263f>] print_circular_bug+0x10f/0x120 [<ffffffff810c481e>] check_prev_add+0x43e/0x4b0 [<ffffffff810c4ee6>] validate_chain+0x656/0x7c0 [<ffffffff810c53d2>] __lock_acquire+0x382/0x660 [<ffffffff810c57a9>] lock_acquire+0xf9/0x170 [<ffffffff815aa13f>] mutex_lock_nested+0x6f/0x380 [<ffffffff8110e3d7>] cgroup_transfer_tasks+0x37/0x150 [<ffffffff811129c0>] hotplug_update_tasks_insane+0x110/0x1d0 [<ffffffff81112bbd>] cpuset_hotplug_update_tasks+0x13d/0x180 [<ffffffff811148ec>] cpuset_hotplug_workfn+0x18c/0x630 [<ffffffff810854d4>] process_one_work+0x254/0x520 [<ffffffff810875dd>] worker_thread+0x13d/0x3d0 [<ffffffff8108e0c8>] kthread+0xf8/0x100 [<ffffffff815acaec>] ret_from_fork+0x7c/0xb0 Signed-off-by: Tejun Heo <[email protected]> Reported-by: Li Zefan <[email protected]> Tested-by: Li Zefan <[email protected]>

This fixes the following lockdep complaint: [ INFO: possible circular locking dependency detected ] 3.16.0-rc2-mm1+ #7 Tainted: G O ------------------------------------------------------- kworker/u24:0/4356 is trying to acquire lock: (&(&sbi->s_es_lru_lock)->rlock){+.+.-.}, at: [<ffffffff81285fff>] __ext4_es_shrink+0x4f/0x2e0 but task is already holding lock: (&ei->i_es_lock){++++-.}, at: [<ffffffff81286961>] ext4_es_insert_extent+0x71/0x180 which lock already depends on the new lock. Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->i_es_lock); lock(&(&sbi->s_es_lru_lock)->rlock); lock(&ei->i_es_lock); lock(&(&sbi->s_es_lru_lock)->rlock); *** DEADLOCK *** 6 locks held by kworker/u24:0/4356: #0: ("writeback"){.+.+.+}, at: [<ffffffff81071d00>] process_one_work+0x180/0x560 #1: ((&(&wb->dwork)->work)){+.+.+.}, at: [<ffffffff81071d00>] process_one_work+0x180/0x560 #2: (&type->s_umount_key#22){++++++}, at: [<ffffffff811a9c74>] grab_super_passive+0x44/0x90 #3: (jbd2_handle){+.+...}, at: [<ffffffff812979f9>] start_this_handle+0x189/0x5f0 #4: (&ei->i_data_sem){++++..}, at: [<ffffffff81247062>] ext4_map_blocks+0x132/0x550 #5: (&ei->i_es_lock){++++-.}, at: [<ffffffff81286961>] ext4_es_insert_extent+0x71/0x180 stack backtrace: CPU: 0 PID: 4356 Comm: kworker/u24:0 Tainted: G O 3.16.0-rc2-mm1+ #7 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Workqueue: writeback bdi_writeback_workfn (flush-253:0) ffffffff8213dce0 ffff880014b07538 ffffffff815df0bb 0000000000000007 ffffffff8213e040 ffff880014b07588 ffffffff815db3dd ffff880014b07568 ffff880014b07610 ffff88003b868930 ffff88003b868908 ffff88003b868930 Call Trace: [<ffffffff815df0bb>] dump_stack+0x4e/0x68 [<ffffffff815db3dd>] print_circular_bug+0x1fb/0x20c [<ffffffff810a7a3e>] __lock_acquire+0x163e/0x1d00 [<ffffffff815e89dc>] ? retint_restore_args+0xe/0xe [<ffffffff815ddc7b>] ? __slab_alloc+0x4a8/0x4ce [<ffffffff81285fff>] ? __ext4_es_shrink+0x4f/0x2e0 [<ffffffff810a8707>] lock_acquire+0x87/0x120 [<ffffffff81285fff>] ? __ext4_es_shrink+0x4f/0x2e0 [<ffffffff8128592d>] ? ext4_es_free_extent+0x5d/0x70 [<ffffffff815e6f09>] _raw_spin_lock+0x39/0x50 [<ffffffff81285fff>] ? __ext4_es_shrink+0x4f/0x2e0 [<ffffffff8119760b>] ? kmem_cache_alloc+0x18b/0x1a0 [<ffffffff81285fff>] __ext4_es_shrink+0x4f/0x2e0 [<ffffffff812869b8>] ext4_es_insert_extent+0xc8/0x180 [<ffffffff812470f4>] ext4_map_blocks+0x1c4/0x550 [<ffffffff8124c4c4>] ext4_writepages+0x6d4/0xd00 ... Reported-by: Minchan Kim <[email protected]> Signed-off-by: Theodore Ts'o <[email protected]> Reported-by: Minchan Kim <[email protected]> Cc: [email protected] Cc: Zheng Liu <[email protected]>

This reverts commit a640616 ("slab: remove BAD_ALIEN_MAGIC"). commit a640616 ("slab: remove BAD_ALIEN_MAGIC") assumes that the system with !CONFIG_NUMA has only one memory node. But, it turns out to be false by the report from Geert. His system, m68k, has many memory nodes and is configured in !CONFIG_NUMA. So it couldn't boot with above change. Here goes his failure report. With latest mainline, I'm getting a crash during bootup on m68k/ARAnyM: enable_cpucache failed for radix_tree_node, error 12. kernel BUG at /scratch/geert/linux/linux-m68k/mm/slab.c:1522! *** TRAP #7 *** FORMAT=0 Current process id is 0 BAD KERNEL TRAP: 00000000 Modules linked in: PC: [<0039c92c>] kmem_cache_init_late+0x70/0x8c SR: 2200 SP: 00345f90 a2: 0034c2e8 d0: 0000003d d1: 00000000 d2: 00000000 d3: 003ac942 d4: 00000000 d5: 00000000 a0: 0034f686 a1: 0034f682 Process swapper (pid: 0, task=0034c2e8) Frame format=0 Stack from 00345fc4: 002f69ef 002ff7e5 000005f2 000360fa 0017d806 003921d4 00000000 00000000 00000000 00000000 00000000 00000000 003ac942 00000000 003912d6 Call Trace: [<000360fa>] parse_args+0x0/0x2ca [<0017d806>] strlen+0x0/0x1a [<003921d4>] start_kernel+0x23c/0x428 [<003912d6>] _sinittext+0x2d6/0x95e Code: f7e5 4879 002f 69ef 61ff ffca 462a 4e47 <4879> 0035 4b1c 61ff fff0 0cc4 7005 23c0 0037 fd20 588f 265f 285f 4e75 48e7 301c Disabling lock debugging due to kernel taint Kernel panic - not syncing: Attempted to kill the idle task! Although there is a alternative way to fix this issue such as disabling use of alien cache on !CONFIG_NUMA, but, reverting issued commit is better to me in this time. Signed-off-by: Joonsoo Kim <[email protected]> Reported-by: Geert Uytterhoeven <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: David Rientjes <[email protected]> Cc: Vladimir Davydov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>

…he maximum open files The soft maximum number of open files for a calling process is 1024, which is defined as INR_OPEN_CUR in include/uapi/linux/fs.h, and the hard maximum number of open files for a calling process is 4096, which is defined as INR_OPEN_MAX in include/uapi/linux/fs.h. Both INR_OPEN_CUR and INR_OPEN_MAX are used to limit the value of RLIMIT_NOFILE in include/asm-generic/resource.h. And the soft maximum number finally decides the limitation of the maximum files which are allowed to be opened. That is to say a process can use at most 1024 file descriptors for its o pened files, or an EMFILE error will happen. This error can be fixed by increasing the soft maximum number, under the constraint that the soft maximum number can not exceed the hard maximum number, or both soft and hard maximum number should be increased simultaneously with privilege. For perf sched replay, it uses sys_perf_event_open to create the file descriptor for each of the tasks in order to handle information of perf events. That is to say each task needs a unique file descriptor. In x86_64, there may be over 1024 or 4096 tasks correspoinding to the record in perf.data, which causes that no enough file descriptors can be used. As a result, EMFILE error happens and stops the replay process. To solve this problem, we adaptively increase the soft and hard maximum number of open files with a '-f' option. Example: Test environment: x86_64 with 160 cores $ cat /proc/sys/kernel/pid_max 163840 $ cat /proc/sys/fs/file-max 6815744 $ ulimit -Sn 1024 $ ulimit -Hn 4096 Before this patch: $ perf sched replay ... task 1549 ( :163132: 163132), nr_events: 1 task 1550 ( :163540: 163540), nr_events: 1 task 1551 ( <unknown>: 0), nr_events: 10 Error: sys_perf_event_open() syscall returned with -1 (Too many open files) After this patch: $ perf sched replay ... task 1549 ( :163132: 163132), nr_events: 1 task 1550 ( :163540: 163540), nr_events: 1 task 1551 ( <unknown>: 0), nr_events: 10 Error: sys_perf_event_open() syscall returned with -1 (Too many open files) Have a try with -f option $ perf sched replay -f ... task 1549 ( :163132: 163132), nr_events: 1 task 1550 ( :163540: 163540), nr_events: 1 task 1551 ( <unknown>: 0), nr_events: 10 ------------------------------------------------------------ #1 : 54.401, ravg: 54.40, cpu: 3285.21 / 3285.21 #2 : 199.548, ravg: 68.92, cpu: 4999.65 / 3456.66 #3 : 170.483, ravg: 79.07, cpu: 1349.94 / 3245.99 #4 : 192.034, ravg: 90.37, cpu: 1322.88 / 3053.67 #5 : 182.929, ravg: 99.62, cpu: 1406.51 / 2888.96 #6 : 152.974, ravg: 104.96, cpu: 1167.54 / 2716.82 #7 : 155.579, ravg: 110.02, cpu: 2992.53 / 2744.39 #8 : 130.557, ravg: 112.08, cpu: 1126.43 / 2582.59 #9 : 138.520, ravg: 114.72, cpu: 1253.22 / 2449.65 torvalds#10 : 134.328, ravg: 116.68, cpu: 1587.95 / 2363.48 Signed-off-by: Yunlong Song <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Wang Nan <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

Enable to use perf.data when it is not owned by current user or root. Example: $ ls -al perf.data -rw------- 1 Yunlong.Song Yunlong.Song 5321918 Mar 25 15:14 perf.data $ sudo id uid=0(root) gid=0(root) groups=0(root),64(pkcs11) Before this patch: $ sudo perf sched replay -f run measurement overhead: 98 nsecs sleep measurement overhead: 52909 nsecs the run test took 1000015 nsecs the sleep test took 1054253 nsecs File perf.data not owned by current user or root (use -f to override) As shown above, the -f option does not work at all. After this patch: $ sudo perf sched replay -f run measurement overhead: 221 nsecs sleep measurement overhead: 40514 nsecs the run test took 1000003 nsecs the sleep test took 1056098 nsecs nr_run_events: 10 nr_sleep_events: 1562 nr_wakeup_events: 5 task 0 ( :1: 1), nr_events: 1 task 1 ( :2: 2), nr_events: 1 task 2 ( :3: 3), nr_events: 1 ... ... task 1549 ( :163132: 163132), nr_events: 1 task 1550 ( :163540: 163540), nr_events: 1 task 1551 ( <unknown>: 0), nr_events: 10 ------------------------------------------------------------ #1 : 50.198, ravg: 50.20, cpu: 2335.18 / 2335.18 #2 : 219.099, ravg: 67.09, cpu: 2835.11 / 2385.17 #3 : 238.626, ravg: 84.24, cpu: 3278.26 / 2474.48 #4 : 200.364, ravg: 95.85, cpu: 2977.41 / 2524.77 #5 : 176.882, ravg: 103.96, cpu: 2801.35 / 2552.43 #6 : 191.093, ravg: 112.67, cpu: 2813.70 / 2578.56 #7 : 189.448, ravg: 120.35, cpu: 2809.21 / 2601.62 #8 : 200.637, ravg: 128.38, cpu: 2849.91 / 2626.45 #9 : 248.338, ravg: 140.37, cpu: 4380.61 / 2801.87 torvalds#10 : 511.139, ravg: 177.45, cpu: 3077.73 / 2829.45 As shown above, the -f option really works now. Besides for replay, -f option can also work for latency and map. Signed-off-by: Yunlong Song <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Wang Nan <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

Rather than have code which masks and then shifts, such as: mrc p15, 1, r0, c0, c0, 1 ALT_SMP(ands r3, r0, #7 << 21) ALT_UP( ands r3, r0, #7 << 27) ALT_SMP(mov r3, r3, lsr torvalds#20) ALT_UP( mov r3, r3, lsr torvalds#26) re-arrange this as a shift and then mask. The masking is the same for each field which we want to extract, so this allows the mask to be shared amongst code paths: mrc p15, 1, r0, c0, c0, 1 ALT_SMP(mov r3, r0, lsr torvalds#20) ALT_UP( mov r3, r0, lsr torvalds#26) ands r3, r3, #7 << 1 Use this method for the LoUIS, LoUU and LoC fields. Reviewed-by: Catalin Marinas <[email protected]> Signed-off-by: Russell King <[email protected]>

Perf top raise a warning if a kernel sample is collected but kernel map is restricted. The warning message needs to dereference al.map->dso... However, previous perf_event__preprocess_sample() doesn't always guarantee al.map != NULL, for example, when kernel map is restricted. This patch validates al.map before dereferencing, avoid the segfault. Before this patch: $ cat /proc/sys/kernel/kptr_restrict 1 $ perf top -p 120183 perf: Segmentation fault -------- backtrace -------- /path/to/perf[0x509868] /lib64/libc.so.6(+0x3545f)[0x7f9a1540045f] /path/to/perf[0x448820] /path/to/perf(cmd_top+0xe3c)[0x44a5dc] /path/to/perf[0x4766a2] /path/to/perf(main+0x5f5)[0x42e545] /lib64/libc.so.6(__libc_start_main+0xf4)[0x7f9a153ecbd4] /path/to/perf[0x42e674] And gdb call trace: Program received signal SIGSEGV, Segmentation fault. perf_event__process_sample (machine=0xa44030, sample=0x7fffffffa4c0, evsel=0xa43b00, event=0x7ffff41c3000, tool=0x7fffffffa8a0) at builtin-top.c:736 736 !RB_EMPTY_ROOT(&al.map->dso->symbols[MAP__FUNCTION]) ? (gdb) bt #0 perf_event__process_sample (machine=0xa44030, sample=0x7fffffffa4c0, evsel=0xa43b00, event=0x7ffff41c3000, tool=0x7fffffffa8a0) at builtin-top.c:736 #1 perf_top__mmap_read_idx (top=top@entry=0x7fffffffa8a0, idx=idx@entry=0) at builtin-top.c:855 #2 0x000000000044a5dd in perf_top__mmap_read (top=0x7fffffffa8a0) at builtin-top.c:872 #3 __cmd_top (top=0x7fffffffa8a0) at builtin-top.c:997 #4 cmd_top (argc=<optimized out>, argv=<optimized out>, prefix=<optimized out>) at builtin-top.c:1267 #5 0x00000000004766a3 in run_builtin (p=p@entry=0x8a6ce8 <commands+264>, argc=argc@entry=3, argv=argv@entry=0x7fffffffdf70) at perf.c:371 #6 0x000000000042e546 in handle_internal_command (argv=0x7fffffffdf70, argc=3) at perf.c:430 #7 run_argv (argv=0x7fffffffdcf0, argcp=0x7fffffffdcfc) at perf.c:474 #8 main (argc=3, argv=0x7fffffffdf70) at perf.c:589 (gdb) Signed-off-by: Wang Nan <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: David Ahern <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Zefan Li <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

It turns out that a PV domU also requires the "Xen PV" APIC driver. Otherwise, the flat driver is used and we get stuck in busy loops that never exit, such as in this stack trace: (gdb) target remote localhost:9999 Remote debugging using localhost:9999 __xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56 56 while (native_apic_mem_read(APIC_ICR) & APIC_ICR_BUSY) (gdb) bt #0 __xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56 #1 __default_send_IPI_shortcut (shortcut=<optimized out>, dest=<optimized out>, vector=<optimized out>) at ./arch/x86/include/asm/ipi.h:75 #2 apic_send_IPI_self (vector=246) at arch/x86/kernel/apic/probe_64.c:54 #3 0xffffffff81011336 in arch_irq_work_raise () at arch/x86/kernel/irq_work.c:47 #4 0xffffffff8114990c in irq_work_queue (work=0xffff88000fc0e400) at kernel/irq_work.c:100 #5 0xffffffff8110c29d in wake_up_klogd () at kernel/printk/printk.c:2633 #6 0xffffffff8110ca60 in vprintk_emit (facility=0, level=<optimized out>, dict=0x0 <irq_stack_union>, dictlen=<optimized out>, fmt=<optimized out>, args=<optimized out>) at kernel/printk/printk.c:1778 #7 0xffffffff816010c8 in printk (fmt=<optimized out>) at kernel/printk/printk.c:1868 #8 0xffffffffc00013ea in ?? () #9 0x0000000000000000 in ?? () Mailing-list-thread: https://lkml.org/lkml/2015/8/4/755 Signed-off-by: Jason A. Donenfeld <[email protected]> Cc: <[email protected]> Signed-off-by: David Vrabel <[email protected]>

commit 6fa92e2 upstream. we found this issue but still exit in lastest kernel. Simply keep ion_handle_create under mutex_lock to avoid this race. WARNING: CPU: 2 PID: 2648 at drivers/staging/android/ion/ion.c:512 ion_handle_add+0xb4/0xc0() ion_handle_add: buffer already found. Modules linked in: iwlmvm iwlwifi mac80211 cfg80211 compat CPU: 2 PID: 2648 Comm: TimedEventQueue Tainted: G W 3.14.0 #7 00000000 00000000 9a3efd2c 80faf273 9a3efd6c 9a3efd5c 80935dc9 811d7fd3 9a3efd88 00000a58 812208a0 00000200 80e128d4 80e128d4 8d4ae00c a8cd8600 a8cd8094 9a3efd74 80935e0e 00000009 9a3efd6c 811d7fd3 9a3efd88 9a3efd9c Call Trace: [<80faf273>] dump_stack+0x48/0x69 [<80935dc9>] warn_slowpath_common+0x79/0x90 [<80e128d4>] ? ion_handle_add+0xb4/0xc0 [<80e128d4>] ? ion_handle_add+0xb4/0xc0 [<80935e0e>] warn_slowpath_fmt+0x2e/0x30 [<80e128d4>] ion_handle_add+0xb4/0xc0 [<80e144cc>] ion_import_dma_buf+0x8c/0x110 [<80c517c4>] reg_init+0x364/0x7d0 [<80993363>] ? futex_wait+0x123/0x210 [<80992e0e>] ? get_futex_key+0x16e/0x1e0 [<8099308f>] ? futex_wake+0x5f/0x120 [<80c51e19>] vpu_service_ioctl+0x1e9/0x500 [<80994aec>] ? do_futex+0xec/0x8e0 [<80971080>] ? prepare_to_wait_event+0xc0/0xc0 [<80c51c30>] ? reg_init+0x7d0/0x7d0 [<80a22562>] do_vfs_ioctl+0x2d2/0x4c0 [<80b198ad>] ? inode_has_perm.isra.41+0x2d/0x40 [<80b199cf>] ? file_has_perm+0x7f/0x90 [<80b1a5f7>] ? selinux_file_ioctl+0x47/0xf0 [<80a227a8>] SyS_ioctl+0x58/0x80 [<80fb45e8>] syscall_call+0x7/0x7 [<80fb0000>] ? mmc_do_calc_max_discard+0xab/0xe4 Fixes: 83271f6 ("ion: hold reference to handle...") Signed-off-by: Shawn Lin <[email protected]> Reviewed-by: Laura Abbott <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit e81107d upstream. My colleague ran into a program stall on a x86_64 server, where n_tty_read() was waiting for data even if there was data in the buffer in the pty. kernel stack for the stuck process looks like below. #0 [ffff88303d107b58] __schedule at ffffffff815c4b20 #1 [ffff88303d107bd0] schedule at ffffffff815c513e #2 [ffff88303d107bf0] schedule_timeout at ffffffff815c7818 #3 [ffff88303d107ca0] wait_woken at ffffffff81096bd2 #4 [ffff88303d107ce0] n_tty_read at ffffffff8136fa23 #5 [ffff88303d107dd0] tty_read at ffffffff81368013 #6 [ffff88303d107e20] __vfs_read at ffffffff811a3704 #7 [ffff88303d107ec0] vfs_read at ffffffff811a3a57 #8 [ffff88303d107f00] sys_read at ffffffff811a4306 #9 [ffff88303d107f50] entry_SYSCALL_64_fastpath at ffffffff815c86d7 There seems to be two problems causing this issue. First, in drivers/tty/n_tty.c, __receive_buf() stores the data and updates ldata->commit_head using smp_store_release() and then checks the wait queue using waitqueue_active(). However, since there is no memory barrier, __receive_buf() could return without calling wake_up_interactive_poll(), and at the same time, n_tty_read() could start to wait in wait_woken() as in the following chart. __receive_buf() n_tty_read() ------------------------------------------------------------------------ if (waitqueue_active(&tty->read_wait)) /* Memory operations issued after the RELEASE may be completed before the RELEASE operation has completed */ add_wait_queue(&tty->read_wait, &wait); ... if (!input_available_p(tty, 0)) { smp_store_release(&ldata->commit_head, ldata->read_head); ... timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); ------------------------------------------------------------------------ The second problem is that n_tty_read() also lacks a memory barrier call and could also cause __receive_buf() to return without calling wake_up_interactive_poll(), and n_tty_read() to wait in wait_woken() as in the chart below. __receive_buf() n_tty_read() ------------------------------------------------------------------------ spin_lock_irqsave(&q->lock, flags); /* from add_wait_queue() */ ... if (!input_available_p(tty, 0)) { /* Memory operations issued after the RELEASE may be completed before the RELEASE operation has completed */ smp_store_release(&ldata->commit_head, ldata->read_head); if (waitqueue_active(&tty->read_wait)) __add_wait_queue(q, wait); spin_unlock_irqrestore(&q->lock,flags); /* from add_wait_queue() */ ... timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); ------------------------------------------------------------------------ There are also other places in drivers/tty/n_tty.c which have similar calls to waitqueue_active(), so instead of adding many memory barrier calls, this patch simply removes the call to waitqueue_active(), leaving just wake_up*() behind. This fixes both problems because, even though the memory access before or after the spinlocks in both wake_up*() and add_wait_queue() can sneak into the critical section, it cannot go past it and the critical section assures that they will be serialized (please see "INTER-CPU ACQUIRING BARRIER EFFECTS" in Documentation/memory-barriers.txt for a better explanation). Moreover, the resulting code is much simpler. Latency measurement using a ping-pong test over a pty doesn't show any visible performance drop. Signed-off-by: Kosuke Tatsukawa <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit c70b17b ] Reducing real_num_tx_queues needs to be in sync with skb queue_mapping otherwise skbs with queue_mapping greater than real_num_tx_queues can be sent to the underlying driver and can result in kernel panic. One such event is running netconsole and enabling VF on the same device. Or running netconsole and changing number of tx queues via ethtool on same device. e.g. Unable to handle kernel NULL pointer dereference tsk->{mm,active_mm}->context = 0000000000001525 tsk->{mm,active_mm}->pgd = fff800130ff9a000 \|/ ____ \|/ "@'/ .. \`@" /_| \__/ |_\ \__U_/ kworker/48:1(475): Oops [#1] CPU: 48 PID: 475 Comm: kworker/48:1 Tainted: G OE 4.11.0-rc3-davem-net+ #7 Workqueue: events queue_process task: fff80013113299c0 task.stack: fff800131132c000 TSTATE: 0000004480e01600 TPC: 00000000103f9e3c TNPC: 00000000103f9e40 Y: 00000000 Tainted: G OE TPC: <ixgbe_xmit_frame_ring+0x7c/0x6c0 [ixgbe]> g0: 0000000000000000 g1: 0000000000003fff g2: 0000000000000000 g3: 0000000000000001 g4: fff80013113299c0 g5: fff8001fa6808000 g6: fff800131132c000 g7: 00000000000000c0 o0: fff8001fa760c460 o1: fff8001311329a50 o2: fff8001fa7607504 o3: 0000000000000003 o4: fff8001f96e63a40 o5: fff8001311d77ec0 sp: fff800131132f0e1 ret_pc: 000000000049ed94 RPC: <set_next_entity+0x34/0xb80> l0: 0000000000000000 l1: 0000000000000800 l2: 0000000000000000 l3: 0000000000000000 l4: 000b2aa30e34b10d l5: 0000000000000000 l6: 0000000000000000 l7: fff8001fa7605028 i0: fff80013111a8a00 i1: fff80013155a0780 i2: 0000000000000000 i3: 0000000000000000 i4: 0000000000000000 i5: 0000000000100000 i6: fff800131132f1a1 i7: 00000000103fa4b0 I7: <ixgbe_xmit_frame+0x30/0xa0 [ixgbe]> Call Trace: [00000000103fa4b0] ixgbe_xmit_frame+0x30/0xa0 [ixgbe] [0000000000998c74] netpoll_start_xmit+0xf4/0x200 [0000000000998e10] queue_process+0x90/0x160 [0000000000485fa8] process_one_work+0x188/0x480 [0000000000486410] worker_thread+0x170/0x4c0 [000000000048c6b8] kthread+0xd8/0x120 [0000000000406064] ret_from_fork+0x1c/0x2c [0000000000000000] (null) Disabling lock debugging due to kernel taint Caller[00000000103fa4b0]: ixgbe_xmit_frame+0x30/0xa0 [ixgbe] Caller[0000000000998c74]: netpoll_start_xmit+0xf4/0x200 Caller[0000000000998e10]: queue_process+0x90/0x160 Caller[0000000000485fa8]: process_one_work+0x188/0x480 Caller[0000000000486410]: worker_thread+0x170/0x4c0 Caller[000000000048c6b8]: kthread+0xd8/0x120 Caller[0000000000406064]: ret_from_fork+0x1c/0x2c Caller[0000000000000000]: (null) Signed-off-by: Tushar Dave <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

@s

commit 624f5ab upstream. syzkaller reported a NULL pointer dereference in asn1_ber_decoder(). It can be reproduced by the following command, assuming CONFIG_PKCS7_TEST_KEY=y: keyctl add pkcs7_test desc '' @s The bug is that if the data buffer is empty, an integer underflow occurs in the following check: if (unlikely(dp >= datalen - 1)) goto data_overrun_error; This results in the NULL data pointer being dereferenced. Fix it by checking for 'datalen - dp < 2' instead. Also fix the similar check for 'dp >= datalen - n' later in the same function. That one possibly could result in a buffer overread. The NULL pointer dereference was reproducible using the "pkcs7_test" key type but not the "asymmetric" key type because the "asymmetric" key type checks for a 0-length payload before calling into the ASN.1 decoder but the "pkcs7_test" key type does not. The bug report was: BUG: unable to handle kernel NULL pointer dereference at (null) IP: asn1_ber_decoder+0x17f/0xe60 lib/asn1_decoder.c:233 PGD 7b708067 P4D 7b708067 PUD 7b6ee067 PMD 0 Oops: 0000 [#1] SMP Modules linked in: CPU: 0 PID: 522 Comm: syz-executor1 Not tainted 4.14.0-rc8 #7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.3-20171021_125229-anatol 04/01/2014 task: ffff9b6b3798c040 task.stack: ffff9b6b37970000 RIP: 0010:asn1_ber_decoder+0x17f/0xe60 lib/asn1_decoder.c:233 RSP: 0018:ffff9b6b37973c78 EFLAGS: 00010216 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000000021c RDX: ffffffff814a04ed RSI: ffffb1524066e000 RDI: ffffffff910759e0 RBP: ffff9b6b37973d60 R08: 0000000000000001 R09: ffff9b6b3caa4180 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f10ed1f2700(0000) GS:ffff9b6b3ea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000007b6f3000 CR4: 00000000000006f0 Call Trace: pkcs7_parse_message+0xee/0x240 crypto/asymmetric_keys/pkcs7_parser.c:139 verify_pkcs7_signature+0x33/0x180 certs/system_keyring.c:216 pkcs7_preparse+0x41/0x70 crypto/asymmetric_keys/pkcs7_key_type.c:63 key_create_or_update+0x180/0x530 security/keys/key.c:855 SYSC_add_key security/keys/keyctl.c:122 [inline] SyS_add_key+0xbf/0x250 security/keys/keyctl.c:62 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x4585c9 RSP: 002b:00007f10ed1f1bd8 EFLAGS: 00000216 ORIG_RAX: 00000000000000f8 RAX: ffffffffffffffda RBX: 00007f10ed1f2700 RCX: 00000000004585c9 RDX: 0000000020000000 RSI: 0000000020008ffb RDI: 0000000020008000 RBP: 0000000000000000 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000216 R12: 00007fff1b2260ae R13: 00007fff1b2260af R14: 00007f10ed1f2700 R15: 0000000000000000 Code: dd ca ff 48 8b 45 88 48 83 e8 01 4c 39 f0 0f 86 a8 07 00 00 e8 53 dd ca ff 49 8d 46 01 48 89 85 58 ff ff ff 48 8b 85 60 ff ff ff <42> 0f b6 0c 30 89 c8 88 8d 75 ff ff ff 83 e0 1f 89 8d 28 ff ff RIP: asn1_ber_decoder+0x17f/0xe60 lib/asn1_decoder.c:233 RSP: ffff9b6b37973c78 CR2: 0000000000000000 Fixes: 42d5ec2 ("X.509: Add an ASN.1 decoder") Reported-by: syzbot <[email protected]> Signed-off-by: Eric Biggers <[email protected]> Signed-off-by: David Howells <[email protected]> Signed-off-by: James Morris <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

syzbot caught an infinite recursion in nsh_gso_segment(). Problem here is that we need to make sure the NSH header is of reasonable length. BUG: MAX_LOCK_DEPTH too low! turning off the locking correctness validator. depth: 48 max: 48! 48 locks held by syz-executor0/10189: #0: (ptrval) (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x30f/0x34c0 net/core/dev.c:3517 #1: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #1: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #2: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #2: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #3: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #3: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #4: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #4: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #5: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #5: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #6: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #6: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #7: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #7: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #8: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #8: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #9: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #9: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#10: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#10: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#11: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#11: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#12: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#12: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#13: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#13: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#14: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#14: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#15: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#15: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#16: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#16: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#17: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#17: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#18: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#18: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#19: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#19: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#20: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#20: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#21: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#21: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#22: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#22: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#23: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#23: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#24: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#24: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#25: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#25: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#26: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#26: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#27: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#27: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#28: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#28: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#29: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#29: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#30: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#30: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#31: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#31: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 dccp_close: ABORT with 65423 bytes unread torvalds#32: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#32: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#33: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#33: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#34: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#34: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#35: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#35: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#36: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#36: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#37: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#37: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#38: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#38: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#39: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#39: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#40: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#40: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#41: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#41: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#42: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#42: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#43: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#43: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#44: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#44: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#45: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#45: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#46: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#46: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#47: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#47: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 INFO: lockdep is turned off. CPU: 1 PID: 10189 Comm: syz-executor0 Not tainted 4.17.0-rc2+ torvalds#26 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 __lock_acquire+0x1788/0x5140 kernel/locking/lockdep.c:3449 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920 rcu_lock_acquire include/linux/rcupdate.h:246 [inline] rcu_read_lock include/linux/rcupdate.h:632 [inline] skb_mac_gso_segment+0x25b/0x720 net/core/dev.c:2789 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 __skb_gso_segment+0x3bb/0x870 net/core/dev.c:2865 skb_gso_segment include/linux/netdevice.h:4025 [inline] validate_xmit_skb+0x54d/0xd90 net/core/dev.c:3118 validate_xmit_skb_list+0xbf/0x120 net/core/dev.c:3168 sch_direct_xmit+0x354/0x11e0 net/sched/sch_generic.c:312 qdisc_restart net/sched/sch_generic.c:399 [inline] __qdisc_run+0x741/0x1af0 net/sched/sch_generic.c:410 __dev_xmit_skb net/core/dev.c:3243 [inline] __dev_queue_xmit+0x28ea/0x34c0 net/core/dev.c:3551 dev_queue_xmit+0x17/0x20 net/core/dev.c:3616 packet_snd net/packet/af_packet.c:2951 [inline] packet_sendmsg+0x40f8/0x6070 net/packet/af_packet.c:2976 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 __sys_sendto+0x3d7/0x670 net/socket.c:1789 __do_sys_sendto net/socket.c:1801 [inline] __se_sys_sendto net/socket.c:1797 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: c411ed8 ("nsh: add GSO support") Signed-off-by: Eric Dumazet <[email protected]> Cc: Jiri Benc <[email protected]> Reported-by: syzbot <[email protected]> Acked-by: Jiri Benc <[email protected]> Signed-off-by: David S. Miller <[email protected]>

Petr Machata says: ==================== net: ip6_gre: Fixes in headroom handling This series mends some problems in headroom management in ip6_gre module. The current code base has the following three closely-related problems: - ip6gretap tunnels neglect to ensure there's enough writable headroom before pushing GRE headers. - ip6erspan does this, but assumes that dev->needed_headroom is primed. But that doesn't happen until ip6_tnl_xmit() is called later. Thus for the first packet, ip6erspan actually behaves like ip6gretap above. - ip6erspan shares some of the code with ip6gretap, including calculations of needed header length. While there is custom ERSPAN-specific code for calculating the headroom, the computed values are overwritten by the ip6gretap code. The first two issues lead to a kernel panic in situations where a packet is mirrored from a veth device to the device in question. They are fixed, respectively, in patches #1 and #2, which include the full panic trace and a reproducer. The rest of the patchset deals with the last issue. In patches #3 to #6, several functions are split up into reusable parts. Finally in patch #7 these blocks are used to compose ERSPAN-specific callbacks where necessary to fix the hlen calculation. ==================== Signed-off-by: David S. Miller <[email protected]>

Recently during testing, I ran into the following panic: [ 207.892422] Internal error: Accessing user space memory outside uaccess.h routines: 96000004 [#1] SMP [ 207.901637] Modules linked in: binfmt_misc [...] [ 207.966530] CPU: 45 PID: 2256 Comm: test_verifier Tainted: G W 4.17.0-rc3+ #7 [ 207.974956] Hardware name: FOXCONN R2-1221R-A4/C2U4N_MB, BIOS G31FB18A 03/31/2017 [ 207.982428] pstate: 60400005 (nZCv daif +PAN -UAO) [ 207.987214] pc : bpf_skb_load_helper_8_no_cache+0x34/0xc0 [ 207.992603] lr : 0xffff000000bdb754 [ 207.996080] sp : ffff000013703ca0 [ 207.999384] x29: ffff000013703ca0 x28: 0000000000000001 [ 208.004688] x27: 0000000000000001 x26: 0000000000000000 [ 208.009992] x25: ffff000013703ce0 x24: ffff800fb4afcb00 [ 208.015295] x23: ffff00007d2f5038 x22: ffff00007d2f5000 [ 208.020599] x21: fffffffffeff2a6f x20: 000000000000000a [ 208.025903] x19: ffff000009578000 x18: 0000000000000a03 [ 208.031206] x17: 0000000000000000 x16: 0000000000000000 [ 208.036510] x15: 0000ffff9de83000 x14: 0000000000000000 [ 208.041813] x13: 0000000000000000 x12: 0000000000000000 [ 208.047116] x11: 0000000000000001 x10: ffff0000089e7f18 [ 208.052419] x9 : fffffffffeff2a6f x8 : 0000000000000000 [ 208.057723] x7 : 000000000000000a x6 : 00280c6160000000 [ 208.063026] x5 : 0000000000000018 x4 : 0000000000007db6 [ 208.068329] x3 : 000000000008647a x2 : 19868179b1484500 [ 208.073632] x1 : 0000000000000000 x0 : ffff000009578c08 [ 208.078938] Process test_verifier (pid: 2256, stack limit = 0x0000000049ca7974) [ 208.086235] Call trace: [ 208.088672] bpf_skb_load_helper_8_no_cache+0x34/0xc0 [ 208.093713] 0xffff000000bdb754 [ 208.096845] bpf_test_run+0x78/0xf8 [ 208.100324] bpf_prog_test_run_skb+0x148/0x230 [ 208.104758] sys_bpf+0x314/0x1198 [ 208.108064] el0_svc_naked+0x30/0x34 [ 208.111632] Code: 91302260 f9400001 f9001fa1 d2800001 (29500680) [ 208.117717] ---[ end trace 263cb8a59b5bf29f ]--- The program itself which caused this had a long jump over the whole instruction sequence where all of the inner instructions required heavy expansions into multiple BPF instructions. Additionally, I also had BPF hardening enabled which requires once more rewrites of all constant values in order to blind them. Each time we rewrite insns, bpf_adj_branches() would need to potentially adjust branch targets which cross the patchlet boundary to accommodate for the additional delta. Eventually that lead to the case where the target offset could not fit into insn->off's upper 0x7fff limit anymore where then offset wraps around becoming negative (in s16 universe), or vice versa depending on the jump direction. Therefore it becomes necessary to detect and reject any such occasions in a generic way for native eBPF and cBPF to eBPF migrations. For the latter we can simply check bounds in the bpf_convert_filter()'s BPF_EMIT_JMP helper macro and bail out once we surpass limits. The bpf_patch_insn_single() for native eBPF (and cBPF to eBPF in case of subsequent hardening) is a bit more complex in that we need to detect such truncations before hitting the bpf_prog_realloc(). Thus the latter is split into an extra pass to probe problematic offsets on the original program in order to fail early. With that in place and carefully tested I no longer hit the panic and the rewrites are rejected properly. The above example panic I've seen on bpf-next, though the issue itself is generic in that a guard against this issue in bpf seems more appropriate in this case. Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]>

[ Upstream commit af50e4b ] syzbot caught an infinite recursion in nsh_gso_segment(). Problem here is that we need to make sure the NSH header is of reasonable length. BUG: MAX_LOCK_DEPTH too low! turning off the locking correctness validator. depth: 48 max: 48! 48 locks held by syz-executor0/10189: #0: (ptrval) (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x30f/0x34c0 net/core/dev.c:3517 #1: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #1: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #2: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #2: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #3: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #3: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #4: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #4: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #5: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #5: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #6: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #6: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #7: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #7: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #8: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #8: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #9: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #9: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#10: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#10: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#11: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#11: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#12: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#12: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#13: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#13: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#14: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#14: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#15: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#15: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#16: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#16: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#17: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#17: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#18: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#18: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#19: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#19: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#20: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#20: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#21: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#21: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#22: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#22: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#23: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#23: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#24: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#24: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#25: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#25: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#26: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#26: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#27: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#27: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#28: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#28: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#29: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#29: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#30: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#30: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#31: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#31: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 dccp_close: ABORT with 65423 bytes unread torvalds#32: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#32: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#33: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#33: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#34: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#34: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#35: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#35: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#36: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#36: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#37: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#37: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#38: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#38: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#39: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#39: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#40: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#40: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#41: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#41: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#42: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#42: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#43: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#43: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#44: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#44: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#45: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#45: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#46: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#46: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#47: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#47: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 INFO: lockdep is turned off. CPU: 1 PID: 10189 Comm: syz-executor0 Not tainted 4.17.0-rc2+ torvalds#26 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 __lock_acquire+0x1788/0x5140 kernel/locking/lockdep.c:3449 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920 rcu_lock_acquire include/linux/rcupdate.h:246 [inline] rcu_read_lock include/linux/rcupdate.h:632 [inline] skb_mac_gso_segment+0x25b/0x720 net/core/dev.c:2789 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 __skb_gso_segment+0x3bb/0x870 net/core/dev.c:2865 skb_gso_segment include/linux/netdevice.h:4025 [inline] validate_xmit_skb+0x54d/0xd90 net/core/dev.c:3118 validate_xmit_skb_list+0xbf/0x120 net/core/dev.c:3168 sch_direct_xmit+0x354/0x11e0 net/sched/sch_generic.c:312 qdisc_restart net/sched/sch_generic.c:399 [inline] __qdisc_run+0x741/0x1af0 net/sched/sch_generic.c:410 __dev_xmit_skb net/core/dev.c:3243 [inline] __dev_queue_xmit+0x28ea/0x34c0 net/core/dev.c:3551 dev_queue_xmit+0x17/0x20 net/core/dev.c:3616 packet_snd net/packet/af_packet.c:2951 [inline] packet_sendmsg+0x40f8/0x6070 net/packet/af_packet.c:2976 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 __sys_sendto+0x3d7/0x670 net/socket.c:1789 __do_sys_sendto net/socket.c:1801 [inline] __se_sys_sendto net/socket.c:1797 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: c411ed8 ("nsh: add GSO support") Signed-off-by: Eric Dumazet <[email protected]> Cc: Jiri Benc <[email protected]> Reported-by: syzbot <[email protected]> Acked-by: Jiri Benc <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit fca3234 ] Executing command 'perf stat -T -- ls' dumps core on x86 and s390. Here is the call back chain (done on x86): # gdb ./perf .... (gdb) r stat -T -- ls ... Program received signal SIGSEGV, Segmentation fault. 0x00007ffff56d1963 in vasprintf () from /lib64/libc.so.6 (gdb) where #0 0x00007ffff56d1963 in vasprintf () from /lib64/libc.so.6 #1 0x00007ffff56ae484 in asprintf () from /lib64/libc.so.6 #2 0x00000000004f1982 in __parse_events_add_pmu (parse_state=0x7fffffffd580, list=0xbfb970, name=0xbf3ef0 "cpu", head_config=0xbfb930, auto_merge_stats=false) at util/parse-events.c:1233 #3 0x00000000004f1c8e in parse_events_add_pmu (parse_state=0x7fffffffd580, list=0xbfb970, name=0xbf3ef0 "cpu", head_config=0xbfb930) at util/parse-events.c:1288 #4 0x0000000000537ce3 in parse_events_parse (_parse_state=0x7fffffffd580, scanner=0xbf4210) at util/parse-events.y:234 #5 0x00000000004f2c7a in parse_events__scanner (str=0x6b66c0 "task-clock,{instructions,cycles,cpu/cycles-t/,cpu/tx-start/}", parse_state=0x7fffffffd580, start_token=258) at util/parse-events.c:1673 #6 0x00000000004f2e23 in parse_events (evlist=0xbe9990, str=0x6b66c0 "task-clock,{instructions,cycles,cpu/cycles-t/,cpu/tx-start/}", err=0x0) at util/parse-events.c:1713 #7 0x000000000044e137 in add_default_attributes () at builtin-stat.c:2281 #8 0x000000000044f7b5 in cmd_stat (argc=1, argv=0x7fffffffe3b0) at builtin-stat.c:2828 #9 0x00000000004c8b0f in run_builtin (p=0xab01a0 <commands+288>, argc=4, argv=0x7fffffffe3b0) at perf.c:297 torvalds#10 0x00000000004c8d7c in handle_internal_command (argc=4, argv=0x7fffffffe3b0) at perf.c:349 torvalds#11 0x00000000004c8ece in run_argv (argcp=0x7fffffffe20c, argv=0x7fffffffe200) at perf.c:393 torvalds#12 0x00000000004c929c in main (argc=4, argv=0x7fffffffe3b0) at perf.c:537 (gdb) It turns out that a NULL pointer is referenced. Here are the function calls: ... cmd_stat() +---> add_default_attributes() +---> parse_events(evsel_list, transaction_attrs, NULL); 3rd parameter set to NULL Function parse_events(xx, xx, struct parse_events_error *err) dives into a bison generated scanner and creates parser state information for it first: struct parse_events_state parse_state = { .list = LIST_HEAD_INIT(parse_state.list), .idx = evlist->nr_entries, .error = err, <--- NULL POINTER !!! .evlist = evlist, }; Now various functions inside the bison scanner are called to end up in __parse_events_add_pmu(struct parse_events_state *parse_state, ..) with first parameter being a pointer to above structure definition. Now the PMU event name is not found (because being executed in a VM) and this function tries to create an error message with asprintf(&parse_state->error.str, ....) which references a NULL pointer and dumps core. Fix this by providing a pointer to the necessary error information instead of NULL. Technically only the else part is needed to avoid the core dump, just lets be safe... Signed-off-by: Thomas Richter <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Hendrik Brueckner <[email protected]> Cc: Martin Schwidefsky <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit 2bbea6e ] when mounting an ISO filesystem sometimes (very rarely) the system hangs because of a race condition between two tasks. PID: 6766 TASK: ffff88007b2a6dd0 CPU: 0 COMMAND: "mount" #0 [ffff880078447ae0] __schedule at ffffffff8168d605 #1 [ffff880078447b48] schedule_preempt_disabled at ffffffff8168ed49 #2 [ffff880078447b58] __mutex_lock_slowpath at ffffffff8168c995 #3 [ffff880078447bb8] mutex_lock at ffffffff8168bdef #4 [ffff880078447bd0] sr_block_ioctl at ffffffffa00b6818 [sr_mod] #5 [ffff880078447c10] blkdev_ioctl at ffffffff812fea50 #6 [ffff880078447c70] ioctl_by_bdev at ffffffff8123a8b3 #7 [ffff880078447c90] isofs_fill_super at ffffffffa04fb1e1 [isofs] #8 [ffff880078447da8] mount_bdev at ffffffff81202570 #9 [ffff880078447e18] isofs_mount at ffffffffa04f9828 [isofs] torvalds#10 [ffff880078447e28] mount_fs at ffffffff81202d09 torvalds#11 [ffff880078447e70] vfs_kern_mount at ffffffff8121ea8f torvalds#12 [ffff880078447ea8] do_mount at ffffffff81220fee torvalds#13 [ffff880078447f28] sys_mount at ffffffff812218d6 torvalds#14 [ffff880078447f80] system_call_fastpath at ffffffff81698c49 RIP: 00007fd9ea914e9a RSP: 00007ffd5d9bf648 RFLAGS: 00010246 RAX: 00000000000000a5 RBX: ffffffff81698c49 RCX: 0000000000000010 RDX: 00007fd9ec2bc210 RSI: 00007fd9ec2bc290 RDI: 00007fd9ec2bcf30 RBP: 0000000000000000 R8: 0000000000000000 R9: 0000000000000010 R10: 00000000c0ed0001 R11: 0000000000000206 R12: 00007fd9ec2bc040 R13: 00007fd9eb6b2380 R14: 00007fd9ec2bc210 R15: 00007fd9ec2bcf30 ORIG_RAX: 00000000000000a5 CS: 0033 SS: 002b This task was trying to mount the cdrom. It allocated and configured a super_block struct and owned the write-lock for the super_block->s_umount rwsem. While exclusively owning the s_umount lock, it called sr_block_ioctl and waited to acquire the global sr_mutex lock. PID: 6785 TASK: ffff880078720fb0 CPU: 0 COMMAND: "systemd-udevd" #0 [ffff880078417898] __schedule at ffffffff8168d605 #1 [ffff880078417900] schedule at ffffffff8168dc59 #2 [ffff880078417910] rwsem_down_read_failed at ffffffff8168f605 #3 [ffff880078417980] call_rwsem_down_read_failed at ffffffff81328838 #4 [ffff8800784179d0] down_read at ffffffff8168cde0 #5 [ffff8800784179e8] get_super at ffffffff81201cc7 #6 [ffff880078417a10] __invalidate_device at ffffffff8123a8de #7 [ffff880078417a40] flush_disk at ffffffff8123a94b #8 [ffff880078417a88] check_disk_change at ffffffff8123ab50 #9 [ffff880078417ab0] cdrom_open at ffffffffa00a29e1 [cdrom] torvalds#10 [ffff880078417b68] sr_block_open at ffffffffa00b6f9b [sr_mod] torvalds#11 [ffff880078417b98] __blkdev_get at ffffffff8123ba86 torvalds#12 [ffff880078417bf0] blkdev_get at ffffffff8123bd65 torvalds#13 [ffff880078417c78] blkdev_open at ffffffff8123bf9b torvalds#14 [ffff880078417c90] do_dentry_open at ffffffff811fc7f7 torvalds#15 [ffff880078417cd8] vfs_open at ffffffff811fc9cf torvalds#16 [ffff880078417d00] do_last at ffffffff8120d53d torvalds#17 [ffff880078417db0] path_openat at ffffffff8120e6b2 torvalds#18 [ffff880078417e48] do_filp_open at ffffffff8121082b torvalds#19 [ffff880078417f18] do_sys_open at ffffffff811fdd33 torvalds#20 [ffff880078417f70] sys_open at ffffffff811fde4e torvalds#21 [ffff880078417f80] system_call_fastpath at ffffffff81698c49 RIP: 00007f29438b0c20 RSP: 00007ffc76624b78 RFLAGS: 00010246 RAX: 0000000000000002 RBX: ffffffff81698c49 RCX: 0000000000000000 RDX: 00007f2944a5fa70 RSI: 00000000000a0800 RDI: 00007f2944a5fa70 RBP: 00007f2944a5f540 R8: 0000000000000000 R9: 0000000000000020 R10: 00007f2943614c40 R11: 0000000000000246 R12: ffffffff811fde4e R13: ffff880078417f78 R14: 000000000000000c R15: 00007f2944a4b010 ORIG_RAX: 0000000000000002 CS: 0033 SS: 002b This task tried to open the cdrom device, the sr_block_open function acquired the global sr_mutex lock. The call to check_disk_change() then saw an event flag indicating a possible media change and tried to flush any cached data for the device. As part of the flush, it tried to acquire the super_block->s_umount lock associated with the cdrom device. This was the same super_block as created and locked by the previous task. The first task acquires the s_umount lock and then the sr_mutex_lock; the second task acquires the sr_mutex_lock and then the s_umount lock. This patch fixes the issue by moving check_disk_change() out of cdrom_open() and let the caller take care of it. Signed-off-by: Maurizio Lombardi <[email protected]> Signed-off-by: Jens Axboe <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit 6b31a2f ] Currently the arm/arm64 runtime code registers the runtime servies pagetables with ptdump regardless of whether runtime services page tables have been created. As efi_mm.pgd is NULL in these cases, attempting to dump the efi page tables results in a NULL pointer dereference in the ptdump code: /sys/kernel/debug# cat efi_page_tables [ 479.522600] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 479.522715] Mem abort info: [ 479.522764] ESR = 0x96000006 [ 479.522850] Exception class = DABT (current EL), IL = 32 bits [ 479.522899] SET = 0, FnV = 0 [ 479.522937] EA = 0, S1PTW = 0 [ 479.528200] Data abort info: [ 479.528230] ISV = 0, ISS = 0x00000006 [ 479.528317] CM = 0, WnR = 0 [ 479.528317] user pgtable: 4k pages, 48-bit VAs, pgd = 0000000064ab0cb0 [ 479.528449] [0000000000000000] *pgd=00000000fbbe4003, *pud=00000000fb66e003, *pmd=0000000000000000 [ 479.528600] Internal error: Oops: 96000006 [#1] PREEMPT SMP [ 479.528664] Modules linked in: [ 479.528699] CPU: 0 PID: 2457 Comm: cat Not tainted 4.15.0-rc3-00065-g2ad2ee7ecb5c-dirty #7 [ 479.528799] Hardware name: FVP Base (DT) [ 479.528899] pstate: 00400009 (nzcv daif +PAN -UAO) [ 479.528941] pc : walk_pgd.isra.1+0x20/0x1d0 [ 479.529011] lr : ptdump_walk_pgd+0x30/0x50 [ 479.529105] sp : ffff00000bf4bc20 [ 479.529185] x29: ffff00000bf4bc20 x28: 0000ffff9d22e000 [ 479.529271] x27: 0000000000020000 x26: ffff80007b4c63c0 [ 479.529358] x25: 00000000014000c0 x24: ffff80007c098900 [ 479.529445] x23: ffff00000bf4beb8 x22: 0000000000000000 [ 479.529532] x21: ffff00000bf4bd70 x20: 0000000000000001 [ 479.529618] x19: ffff00000bf4bcb0 x18: 0000000000000000 [ 479.529760] x17: 000000000041a1c8 x16: ffff0000082139d8 [ 479.529800] x15: 0000ffff9d3c6030 x14: 0000ffff9d2527f4 [ 479.529924] x13: 00000000000003f3 x12: 0000000000000038 [ 479.530000] x11: 0000000000000003 x10: 0101010101010101 [ 479.530099] x9 : 0000000017e94050 x8 : 000000000000003f [ 479.530226] x7 : 0000000000000000 x6 : 0000000000000000 [ 479.530313] x5 : 0000000000000001 x4 : 0000000000000000 [ 479.530416] x3 : ffff000009069fd8 x2 : 0000000000000000 [ 479.530500] x1 : 0000000000000000 x0 : 0000000000000000 [ 479.530599] Process cat (pid: 2457, stack limit = 0x000000005d1b0e6f) [ 479.530660] Call trace: [ 479.530746] walk_pgd.isra.1+0x20/0x1d0 [ 479.530833] ptdump_walk_pgd+0x30/0x50 [ 479.530907] ptdump_show+0x10/0x20 [ 479.530920] seq_read+0xc8/0x470 [ 479.531023] full_proxy_read+0x60/0x90 [ 479.531100] __vfs_read+0x18/0x100 [ 479.531180] vfs_read+0x88/0x160 [ 479.531267] SyS_read+0x48/0xb0 [ 479.531299] el0_svc_naked+0x20/0x24 [ 479.531400] Code: 91400420 f90033a0 a90707a2 f9403fa0 (f9400000) [ 479.531499] ---[ end trace bfe8e28d8acb2b67 ]--- Segmentation fault Let's avoid this problem by only registering the tables after their successful creation, which is also less confusing when EFI runtime services are not in use. Reported-by: Will Deacon <[email protected]> Signed-off-by: Mark Rutland <[email protected]> Signed-off-by: Ard Biesheuvel <[email protected]> Acked-by: Will Deacon <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Matt Fleming <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit 0216234 upstream. We release wrong pointer on error path in cpu_cache_level__read function, leading to segfault: (gdb) r record ls Starting program: /root/perf/tools/perf/perf record ls ... [ perf record: Woken up 1 times to write data ] double free or corruption (out) Thread 1 "perf" received signal SIGABRT, Aborted. 0x00007ffff7463798 in raise () from /lib64/power9/libc.so.6 (gdb) bt #0 0x00007ffff7463798 in raise () from /lib64/power9/libc.so.6 #1 0x00007ffff7443bac in abort () from /lib64/power9/libc.so.6 #2 0x00007ffff74af8bc in __libc_message () from /lib64/power9/libc.so.6 #3 0x00007ffff74b92b8 in malloc_printerr () from /lib64/power9/libc.so.6 #4 0x00007ffff74bb874 in _int_free () from /lib64/power9/libc.so.6 #5 0x0000000010271260 in __zfree (ptr=0x7fffffffa0b0) at ../../lib/zalloc.. #6 0x0000000010139340 in cpu_cache_level__read (cache=0x7fffffffa090, cac.. #7 0x0000000010143c90 in build_caches (cntp=0x7fffffffa118, size=<optimiz.. ... Releasing the proper pointer. Fixes: 720e98b ("perf tools: Add perf data cache feature") Signed-off-by: Jiri Olsa <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Michael Petlan <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: [email protected]: # v4.6+ Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit 443f2d5 upstream. Observe a segmentation fault when 'perf stat' is asked to repeat forever with the interval option. Without fix: # perf stat -r 0 -I 5000 -e cycles -a sleep 10 # time counts unit events 5.000211692 3,13,89,82,34,157 cycles 10.000380119 1,53,98,52,22,294 cycles 10.040467280 17,16,79,265 cycles Segmentation fault This problem was only observed when we use forever option aka -r 0 and works with limited repeats. Calling print_counter with ts being set to NULL, is not a correct option when interval is set. Hence avoid print_counter(NULL,..) if interval is set. With fix: # perf stat -r 0 -I 5000 -e cycles -a sleep 10 # time counts unit events 5.019866622 3,15,14,43,08,697 cycles 10.039865756 3,15,16,31,95,261 cycles 10.059950628 1,26,05,47,158 cycles 5.009902655 3,14,52,62,33,932 cycles 10.019880228 3,14,52,22,89,154 cycles 10.030543876 66,90,18,333 cycles 5.009848281 3,14,51,98,25,437 cycles 10.029854402 3,15,14,93,04,918 cycles 5.009834177 3,14,51,95,92,316 cycles Committer notes: Did the 'git bisect' to find the cset introducing the problem to add the Fixes tag below, and at that time the problem reproduced as: (gdb) run stat -r0 -I500 sleep 1 <SNIP> Program received signal SIGSEGV, Segmentation fault. print_interval (prefix=prefix@entry=0x7fffffffc8d0 "", ts=ts@entry=0x0) at builtin-stat.c:866 866 sprintf(prefix, "%6lu.%09lu%s", ts->tv_sec, ts->tv_nsec, csv_sep); (gdb) bt #0 print_interval (prefix=prefix@entry=0x7fffffffc8d0 "", ts=ts@entry=0x0) at builtin-stat.c:866 #1 0x000000000041860a in print_counters (ts=ts@entry=0x0, argc=argc@entry=2, argv=argv@entry=0x7fffffffd640) at builtin-stat.c:938 #2 0x0000000000419a7f in cmd_stat (argc=2, argv=0x7fffffffd640, prefix=<optimized out>) at builtin-stat.c:1411 #3 0x000000000045c65a in run_builtin (p=p@entry=0x6291b8 <commands+216>, argc=argc@entry=5, argv=argv@entry=0x7fffffffd640) at perf.c:370 #4 0x000000000045c893 in handle_internal_command (argc=5, argv=0x7fffffffd640) at perf.c:429 #5 0x000000000045c8f1 in run_argv (argcp=argcp@entry=0x7fffffffd4ac, argv=argv@entry=0x7fffffffd4a0) at perf.c:473 #6 0x000000000045cac9 in main (argc=<optimized out>, argv=<optimized out>) at perf.c:588 (gdb) Mostly the same as just before this patch: Program received signal SIGSEGV, Segmentation fault. 0x00000000005874a7 in print_interval (config=0xa1f2a0 <stat_config>, evlist=0xbc9b90, prefix=0x7fffffffd1c0 "`", ts=0x0) at util/stat-display.c:964 964 sprintf(prefix, "%6lu.%09lu%s", ts->tv_sec, ts->tv_nsec, config->csv_sep); (gdb) bt #0 0x00000000005874a7 in print_interval (config=0xa1f2a0 <stat_config>, evlist=0xbc9b90, prefix=0x7fffffffd1c0 "`", ts=0x0) at util/stat-display.c:964 #1 0x0000000000588047 in perf_evlist__print_counters (evlist=0xbc9b90, config=0xa1f2a0 <stat_config>, _target=0xa1f0c0 <target>, ts=0x0, argc=2, argv=0x7fffffffd670) at util/stat-display.c:1172 #2 0x000000000045390f in print_counters (ts=0x0, argc=2, argv=0x7fffffffd670) at builtin-stat.c:656 #3 0x0000000000456bb5 in cmd_stat (argc=2, argv=0x7fffffffd670) at builtin-stat.c:1960 #4 0x00000000004dd2e0 in run_builtin (p=0xa30e00 <commands+288>, argc=5, argv=0x7fffffffd670) at perf.c:310 #5 0x00000000004dd54d in handle_internal_command (argc=5, argv=0x7fffffffd670) at perf.c:362 #6 0x00000000004dd694 in run_argv (argcp=0x7fffffffd4cc, argv=0x7fffffffd4c0) at perf.c:406 #7 0x00000000004dda11 in main (argc=5, argv=0x7fffffffd670) at perf.c:531 (gdb) Fixes: d4f63a4 ("perf stat: Introduce print_counters function") Signed-off-by: Srikar Dronamraju <[email protected]> Acked-by: Jiri Olsa <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Tested-by: Ravi Bangoria <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Naveen N. Rao <[email protected]> Cc: [email protected] # v4.2+ Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit b0f3b87 ] https://bugzilla.kernel.org/show_bug.cgi?id=208565 PID: 257 TASK: ecdd0000 CPU: 0 COMMAND: "init" #0 [<c0b420ec>] (__schedule) from [<c0b423c8>] #1 [<c0b423c8>] (schedule) from [<c0b459d4>] #2 [<c0b459d4>] (rwsem_down_read_failed) from [<c0b44fa0>] #3 [<c0b44fa0>] (down_read) from [<c044233c>] #4 [<c044233c>] (f2fs_truncate_blocks) from [<c0442890>] #5 [<c0442890>] (f2fs_truncate) from [<c044d408>] #6 [<c044d408>] (f2fs_evict_inode) from [<c030be18>] #7 [<c030be18>] (evict) from [<c030a558>] #8 [<c030a558>] (iput) from [<c047c600>] #9 [<c047c600>] (f2fs_sync_node_pages) from [<c0465414>] torvalds#10 [<c0465414>] (f2fs_write_checkpoint) from [<c04575f4>] torvalds#11 [<c04575f4>] (f2fs_sync_fs) from [<c0441918>] torvalds#12 [<c0441918>] (f2fs_do_sync_file) from [<c0441098>] torvalds#13 [<c0441098>] (f2fs_sync_file) from [<c0323fa0>] torvalds#14 [<c0323fa0>] (vfs_fsync_range) from [<c0324294>] torvalds#15 [<c0324294>] (do_fsync) from [<c0324014>] torvalds#16 [<c0324014>] (sys_fsync) from [<c0108bc0>] This can be caused by flush_dirty_inode() in f2fs_sync_node_pages() where iput() requires f2fs_lock_op() again resulting in livelock. Reported-by: Zhiguo Niu <[email protected]> Signed-off-by: Jaegeuk Kim <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

commit e89c4a9 upstream. I got the following lockdep splat while testing: ====================================================== WARNING: possible circular locking dependency detected 5.8.0-rc7-00172-g021118712e59 torvalds#932 Not tainted ------------------------------------------------------ btrfs/229626 is trying to acquire lock: ffffffff828513f0 (cpu_hotplug_lock){++++}-{0:0}, at: alloc_workqueue+0x378/0x450 but task is already holding lock: ffff889dd3889518 (&fs_info->scrub_lock){+.+.}-{3:3}, at: btrfs_scrub_dev+0x11c/0x630 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #7 (&fs_info->scrub_lock){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_scrub_dev+0x11c/0x630 btrfs_dev_replace_by_ioctl.cold.21+0x10a/0x1d4 btrfs_ioctl+0x2799/0x30a0 ksys_ioctl+0x83/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #6 (&fs_devs->device_list_mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_run_dev_stats+0x49/0x480 commit_cowonly_roots+0xb5/0x2a0 btrfs_commit_transaction+0x516/0xa60 sync_filesystem+0x6b/0x90 generic_shutdown_super+0x22/0x100 kill_anon_super+0xe/0x30 btrfs_kill_super+0x12/0x20 deactivate_locked_super+0x29/0x60 cleanup_mnt+0xb8/0x140 task_work_run+0x6d/0xb0 __prepare_exit_to_usermode+0x1cc/0x1e0 do_syscall_64+0x5c/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #5 (&fs_info->tree_log_mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_commit_transaction+0x4bb/0xa60 sync_filesystem+0x6b/0x90 generic_shutdown_super+0x22/0x100 kill_anon_super+0xe/0x30 btrfs_kill_super+0x12/0x20 deactivate_locked_super+0x29/0x60 cleanup_mnt+0xb8/0x140 task_work_run+0x6d/0xb0 __prepare_exit_to_usermode+0x1cc/0x1e0 do_syscall_64+0x5c/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #4 (&fs_info->reloc_mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_record_root_in_trans+0x43/0x70 start_transaction+0xd1/0x5d0 btrfs_dirty_inode+0x42/0xd0 touch_atime+0xa1/0xd0 btrfs_file_mmap+0x3f/0x60 mmap_region+0x3a4/0x640 do_mmap+0x376/0x580 vm_mmap_pgoff+0xd5/0x120 ksys_mmap_pgoff+0x193/0x230 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #3 (&mm->mmap_lock#2){++++}-{3:3}: __might_fault+0x68/0x90 _copy_to_user+0x1e/0x80 perf_read+0x141/0x2c0 vfs_read+0xad/0x1b0 ksys_read+0x5f/0xe0 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #2 (&cpuctx_mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 perf_event_init_cpu+0x88/0x150 perf_event_init+0x1db/0x20b start_kernel+0x3ae/0x53c secondary_startup_64+0xa4/0xb0 -> #1 (pmus_lock){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 perf_event_init_cpu+0x4f/0x150 cpuhp_invoke_callback+0xb1/0x900 _cpu_up.constprop.26+0x9f/0x130 cpu_up+0x7b/0xc0 bringup_nonboot_cpus+0x4f/0x60 smp_init+0x26/0x71 kernel_init_freeable+0x110/0x258 kernel_init+0xa/0x103 ret_from_fork+0x1f/0x30 -> #0 (cpu_hotplug_lock){++++}-{0:0}: __lock_acquire+0x1272/0x2310 lock_acquire+0x9e/0x360 cpus_read_lock+0x39/0xb0 alloc_workqueue+0x378/0x450 __btrfs_alloc_workqueue+0x15d/0x200 btrfs_alloc_workqueue+0x51/0x160 scrub_workers_get+0x5a/0x170 btrfs_scrub_dev+0x18c/0x630 btrfs_dev_replace_by_ioctl.cold.21+0x10a/0x1d4 btrfs_ioctl+0x2799/0x30a0 ksys_ioctl+0x83/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 other info that might help us debug this: Chain exists of: cpu_hotplug_lock --> &fs_devs->device_list_mutex --> &fs_info->scrub_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fs_info->scrub_lock); lock(&fs_devs->device_list_mutex); lock(&fs_info->scrub_lock); lock(cpu_hotplug_lock); *** DEADLOCK *** 2 locks held by btrfs/229626: #0: ffff88bfe8bb86e0 (&fs_devs->device_list_mutex){+.+.}-{3:3}, at: btrfs_scrub_dev+0xbd/0x630 #1: ffff889dd3889518 (&fs_info->scrub_lock){+.+.}-{3:3}, at: btrfs_scrub_dev+0x11c/0x630 stack backtrace: CPU: 15 PID: 229626 Comm: btrfs Kdump: loaded Not tainted 5.8.0-rc7-00172-g021118712e59 torvalds#932 Hardware name: Quanta Tioga Pass Single Side 01-0030993006/Tioga Pass Single Side, BIOS F08_3A18 12/20/2018 Call Trace: dump_stack+0x78/0xa0 check_noncircular+0x165/0x180 __lock_acquire+0x1272/0x2310 lock_acquire+0x9e/0x360 ? alloc_workqueue+0x378/0x450 cpus_read_lock+0x39/0xb0 ? alloc_workqueue+0x378/0x450 alloc_workqueue+0x378/0x450 ? rcu_read_lock_sched_held+0x52/0x80 __btrfs_alloc_workqueue+0x15d/0x200 btrfs_alloc_workqueue+0x51/0x160 scrub_workers_get+0x5a/0x170 btrfs_scrub_dev+0x18c/0x630 ? start_transaction+0xd1/0x5d0 btrfs_dev_replace_by_ioctl.cold.21+0x10a/0x1d4 btrfs_ioctl+0x2799/0x30a0 ? do_sigaction+0x102/0x250 ? lockdep_hardirqs_on_prepare+0xca/0x160 ? _raw_spin_unlock_irq+0x24/0x30 ? trace_hardirqs_on+0x1c/0xe0 ? _raw_spin_unlock_irq+0x24/0x30 ? do_sigaction+0x102/0x250 ? ksys_ioctl+0x83/0xc0 ksys_ioctl+0x83/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 This happens because we're allocating the scrub workqueues under the scrub and device list mutex, which brings in a whole host of other dependencies. Because the work queue allocation is done with GFP_KERNEL, it can trigger reclaim, which can lead to a transaction commit, which in turns needs the device_list_mutex, it can lead to a deadlock. A different problem for which this fix is a solution. Fix this by moving the actual allocation outside of the scrub lock, and then only take the lock once we're ready to actually assign them to the fs_info. We'll now have to cleanup the workqueues in a few more places, so I've added a helper to do the refcount dance to safely free the workqueues. CC: [email protected] # 5.4+ Reviewed-by: Filipe Manana <[email protected]> Signed-off-by: Josef Bacik <[email protected]> Reviewed-by: David Sterba <[email protected]> Signed-off-by: David Sterba <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit 22fe5a2 ] The aliases were never released causing the following leaks: Indirect leak of 1224 byte(s) in 9 object(s) allocated from: #0 0x7feefb830628 in malloc (/lib/x86_64-linux-gnu/libasan.so.5+0x107628) #1 0x56332c8f1b62 in __perf_pmu__new_alias util/pmu.c:322 #2 0x56332c8f401f in pmu_add_cpu_aliases_map util/pmu.c:778 #3 0x56332c792ce9 in __test__pmu_event_aliases tests/pmu-events.c:295 #4 0x56332c792ce9 in test_aliases tests/pmu-events.c:367 #5 0x56332c76a09b in run_test tests/builtin-test.c:410 #6 0x56332c76a09b in test_and_print tests/builtin-test.c:440 #7 0x56332c76ce69 in __cmd_test tests/builtin-test.c:695 #8 0x56332c76ce69 in cmd_test tests/builtin-test.c:807 #9 0x56332c7d2214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312 torvalds#10 0x56332c6701a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364 torvalds#11 0x56332c6701a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408 torvalds#12 0x56332c6701a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538 torvalds#13 0x7feefb359cc9 in __libc_start_main ../csu/libc-start.c:308 Fixes: 956a783 ("perf test: Test pmu-events aliases") Signed-off-by: Namhyung Kim <[email protected]> Reviewed-by: John Garry <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Ian Rogers <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

[ Upstream commit b12eea5 ] The evsel->unit borrows a pointer of pmu event or alias instead of owns a string. But tool event (duration_time) passes a result of strdup() caused a leak. It was found by ASAN during metric test: Direct leak of 210 byte(s) in 70 object(s) allocated from: #0 0x7fe366fca0b5 in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x920b5) #1 0x559fbbcc6ea3 in add_event_tool util/parse-events.c:414 #2 0x559fbbcc6ea3 in parse_events_add_tool util/parse-events.c:1414 #3 0x559fbbd8474d in parse_events_parse util/parse-events.y:439 #4 0x559fbbcc95da in parse_events__scanner util/parse-events.c:2096 #5 0x559fbbcc95da in __parse_events util/parse-events.c:2141 #6 0x559fbbc28555 in check_parse_id tests/pmu-events.c:406 #7 0x559fbbc28555 in check_parse_id tests/pmu-events.c:393 #8 0x559fbbc28555 in check_parse_cpu tests/pmu-events.c:415 #9 0x559fbbc28555 in test_parsing tests/pmu-events.c:498 torvalds#10 0x559fbbc0109b in run_test tests/builtin-test.c:410 torvalds#11 0x559fbbc0109b in test_and_print tests/builtin-test.c:440 torvalds#12 0x559fbbc03e69 in __cmd_test tests/builtin-test.c:695 torvalds#13 0x559fbbc03e69 in cmd_test tests/builtin-test.c:807 torvalds#14 0x559fbbc691f4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312 torvalds#15 0x559fbbb071a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364 torvalds#16 0x559fbbb071a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408 torvalds#17 0x559fbbb071a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538 torvalds#18 0x7fe366b68cc9 in __libc_start_main ../csu/libc-start.c:308 Fixes: f0fbb11 ("perf stat: Implement duration_time as a proper event") Signed-off-by: Namhyung Kim <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Ian Rogers <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

[ Upstream commit d26383d ] The following leaks were detected by ASAN: Indirect leak of 360 byte(s) in 9 object(s) allocated from: #0 0x7fecc305180e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e) #1 0x560578f6dce5 in perf_pmu__new_format util/pmu.c:1333 #2 0x560578f752fc in perf_pmu_parse util/pmu.y:59 #3 0x560578f6a8b7 in perf_pmu__format_parse util/pmu.c:73 #4 0x560578e07045 in test__pmu tests/pmu.c:155 #5 0x560578de109b in run_test tests/builtin-test.c:410 #6 0x560578de109b in test_and_print tests/builtin-test.c:440 #7 0x560578de401a in __cmd_test tests/builtin-test.c:661 #8 0x560578de401a in cmd_test tests/builtin-test.c:807 #9 0x560578e49354 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312 torvalds#10 0x560578ce71a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364 torvalds#11 0x560578ce71a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408 torvalds#12 0x560578ce71a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538 torvalds#13 0x7fecc2b7acc9 in __libc_start_main ../csu/libc-start.c:308 Fixes: cff7f95 ("perf tests: Move pmu tests into separate object") Signed-off-by: Namhyung Kim <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Ian Rogers <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

commit 66d204a upstream. Very sporadically I had test case btrfs/069 from fstests hanging (for years, it is not a recent regression), with the following traces in dmesg/syslog: [162301.160628] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg started [162301.181196] BTRFS info (device sdc): scrub: finished on devid 4 with status: 0 [162301.287162] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg finished [162513.513792] INFO: task btrfs-transacti:1356167 blocked for more than 120 seconds. [162513.514318] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.514522] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.514747] task:btrfs-transacti state:D stack: 0 pid:1356167 ppid: 2 flags:0x00004000 [162513.514751] Call Trace: [162513.514761] __schedule+0x5ce/0xd00 [162513.514765] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.514771] schedule+0x46/0xf0 [162513.514844] wait_current_trans+0xde/0x140 [btrfs] [162513.514850] ? finish_wait+0x90/0x90 [162513.514864] start_transaction+0x37c/0x5f0 [btrfs] [162513.514879] transaction_kthread+0xa4/0x170 [btrfs] [162513.514891] ? btrfs_cleanup_transaction+0x660/0x660 [btrfs] [162513.514894] kthread+0x153/0x170 [162513.514897] ? kthread_stop+0x2c0/0x2c0 [162513.514902] ret_from_fork+0x22/0x30 [162513.514916] INFO: task fsstress:1356184 blocked for more than 120 seconds. [162513.515192] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.515431] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.515680] task:fsstress state:D stack: 0 pid:1356184 ppid:1356177 flags:0x00004000 [162513.515682] Call Trace: [162513.515688] __schedule+0x5ce/0xd00 [162513.515691] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.515697] schedule+0x46/0xf0 [162513.515712] wait_current_trans+0xde/0x140 [btrfs] [162513.515716] ? finish_wait+0x90/0x90 [162513.515729] start_transaction+0x37c/0x5f0 [btrfs] [162513.515743] btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs] [162513.515753] btrfs_sync_fs+0x61/0x1c0 [btrfs] [162513.515758] ? __ia32_sys_fdatasync+0x20/0x20 [162513.515761] iterate_supers+0x87/0xf0 [162513.515765] ksys_sync+0x60/0xb0 [162513.515768] __do_sys_sync+0xa/0x10 [162513.515771] do_syscall_64+0x33/0x80 [162513.515774] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.515781] RIP: 0033:0x7f5238f50bd7 [162513.515782] Code: Bad RIP value. [162513.515784] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2 [162513.515786] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7 [162513.515788] RDX: 00000000ffffffff RSI: 000000000daf0e74 RDI: 000000000000003a [162513.515789] RBP: 0000000000000032 R08: 000000000000000a R09: 00007f5239019be0 [162513.515791] R10: fffffffffffff24f R11: 0000000000000206 R12: 000000000000003a [162513.515792] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340 [162513.515804] INFO: task fsstress:1356185 blocked for more than 120 seconds. [162513.516064] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.516329] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.516617] task:fsstress state:D stack: 0 pid:1356185 ppid:1356177 flags:0x00000000 [162513.516620] Call Trace: [162513.516625] __schedule+0x5ce/0xd00 [162513.516628] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.516634] schedule+0x46/0xf0 [162513.516647] wait_current_trans+0xde/0x140 [btrfs] [162513.516650] ? finish_wait+0x90/0x90 [162513.516662] start_transaction+0x4d7/0x5f0 [btrfs] [162513.516679] btrfs_setxattr_trans+0x3c/0x100 [btrfs] [162513.516686] __vfs_setxattr+0x66/0x80 [162513.516691] __vfs_setxattr_noperm+0x70/0x200 [162513.516697] vfs_setxattr+0x6b/0x120 [162513.516703] setxattr+0x125/0x240 [162513.516709] ? lock_acquire+0xb1/0x480 [162513.516712] ? mnt_want_write+0x20/0x50 [162513.516721] ? rcu_read_lock_any_held+0x8e/0xb0 [162513.516723] ? preempt_count_add+0x49/0xa0 [162513.516725] ? __sb_start_write+0x19b/0x290 [162513.516727] ? preempt_count_add+0x49/0xa0 [162513.516732] path_setxattr+0xba/0xd0 [162513.516739] __x64_sys_setxattr+0x27/0x30 [162513.516741] do_syscall_64+0x33/0x80 [162513.516743] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.516745] RIP: 0033:0x7f5238f56d5a [162513.516746] Code: Bad RIP value. [162513.516748] RSP: 002b:00007fff67b97868 EFLAGS: 00000202 ORIG_RAX: 00000000000000bc [162513.516750] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f5238f56d5a [162513.516751] RDX: 000055b1fbb0d5a0 RSI: 00007fff67b978a0 RDI: 000055b1fbb0d470 [162513.516753] RBP: 000055b1fbb0d5a0 R08: 0000000000000001 R09: 00007fff67b97700 [162513.516754] R10: 0000000000000004 R11: 0000000000000202 R12: 0000000000000004 [162513.516756] R13: 0000000000000024 R14: 0000000000000001 R15: 00007fff67b978a0 [162513.516767] INFO: task fsstress:1356196 blocked for more than 120 seconds. [162513.517064] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.517365] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.517763] task:fsstress state:D stack: 0 pid:1356196 ppid:1356177 flags:0x00004000 [162513.517780] Call Trace: [162513.517786] __schedule+0x5ce/0xd00 [162513.517789] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.517796] schedule+0x46/0xf0 [162513.517810] wait_current_trans+0xde/0x140 [btrfs] [162513.517814] ? finish_wait+0x90/0x90 [162513.517829] start_transaction+0x37c/0x5f0 [btrfs] [162513.517845] btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs] [162513.517857] btrfs_sync_fs+0x61/0x1c0 [btrfs] [162513.517862] ? __ia32_sys_fdatasync+0x20/0x20 [162513.517865] iterate_supers+0x87/0xf0 [162513.517869] ksys_sync+0x60/0xb0 [162513.517872] __do_sys_sync+0xa/0x10 [162513.517875] do_syscall_64+0x33/0x80 [162513.517878] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.517881] RIP: 0033:0x7f5238f50bd7 [162513.517883] Code: Bad RIP value. [162513.517885] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2 [162513.517887] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7 [162513.517889] RDX: 0000000000000000 RSI: 000000007660add2 RDI: 0000000000000053 [162513.517891] RBP: 0000000000000032 R08: 0000000000000067 R09: 00007f5239019be0 [162513.517893] R10: fffffffffffff24f R11: 0000000000000206 R12: 0000000000000053 [162513.517895] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340 [162513.517908] INFO: task fsstress:1356197 blocked for more than 120 seconds. [162513.518298] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.518672] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.519157] task:fsstress state:D stack: 0 pid:1356197 ppid:1356177 flags:0x00000000 [162513.519160] Call Trace: [162513.519165] __schedule+0x5ce/0xd00 [162513.519168] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.519174] schedule+0x46/0xf0 [162513.519190] wait_current_trans+0xde/0x140 [btrfs] [162513.519193] ? finish_wait+0x90/0x90 [162513.519206] start_transaction+0x4d7/0x5f0 [btrfs] [162513.519222] btrfs_create+0x57/0x200 [btrfs] [162513.519230] lookup_open+0x522/0x650 [162513.519246] path_openat+0x2b8/0xa50 [162513.519270] do_filp_open+0x91/0x100 [162513.519275] ? find_held_lock+0x32/0x90 [162513.519280] ? lock_acquired+0x33b/0x470 [162513.519285] ? do_raw_spin_unlock+0x4b/0xc0 [162513.519287] ? _raw_spin_unlock+0x29/0x40 [162513.519295] do_sys_openat2+0x20d/0x2d0 [162513.519300] do_sys_open+0x44/0x80 [162513.519304] do_syscall_64+0x33/0x80 [162513.519307] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.519309] RIP: 0033:0x7f5238f4a903 [162513.519310] Code: Bad RIP value. [162513.519312] RSP: 002b:00007fff67b97758 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 [162513.519314] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f5238f4a903 [162513.519316] RDX: 0000000000000000 RSI: 00000000000001b6 RDI: 000055b1fbb0d470 [162513.519317] RBP: 00007fff67b978c0 R08: 0000000000000001 R09: 0000000000000002 [162513.519319] R10: 00007fff67b974f7 R11: 0000000000000246 R12: 0000000000000013 [162513.519320] R13: 00000000000001b6 R14: 00007fff67b97906 R15: 000055b1fad1c620 [162513.519332] INFO: task btrfs:1356211 blocked for more than 120 seconds. [162513.519727] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.520115] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.520508] task:btrfs state:D stack: 0 pid:1356211 ppid:1356178 flags:0x00004002 [162513.520511] Call Trace: [162513.520516] __schedule+0x5ce/0xd00 [162513.520519] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.520525] schedule+0x46/0xf0 [162513.520544] btrfs_scrub_pause+0x11f/0x180 [btrfs] [162513.520548] ? finish_wait+0x90/0x90 [162513.520562] btrfs_commit_transaction+0x45a/0xc30 [btrfs] [162513.520574] ? start_transaction+0xe0/0x5f0 [btrfs] [162513.520596] btrfs_dev_replace_finishing+0x6d8/0x711 [btrfs] [162513.520619] btrfs_dev_replace_by_ioctl.cold+0x1cc/0x1fd [btrfs] [162513.520639] btrfs_ioctl+0x2a25/0x36f0 [btrfs] [162513.520643] ? do_sigaction+0xf3/0x240 [162513.520645] ? find_held_lock+0x32/0x90 [162513.520648] ? do_sigaction+0xf3/0x240 [162513.520651] ? lock_acquired+0x33b/0x470 [162513.520655] ? _raw_spin_unlock_irq+0x24/0x50 [162513.520657] ? lockdep_hardirqs_on+0x7d/0x100 [162513.520660] ? _raw_spin_unlock_irq+0x35/0x50 [162513.520662] ? do_sigaction+0xf3/0x240 [162513.520671] ? __x64_sys_ioctl+0x83/0xb0 [162513.520672] __x64_sys_ioctl+0x83/0xb0 [162513.520677] do_syscall_64+0x33/0x80 [162513.520679] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.520681] RIP: 0033:0x7fc3cd307d87 [162513.520682] Code: Bad RIP value. [162513.520684] RSP: 002b:00007ffe30a56bb8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [162513.520686] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fc3cd307d87 [162513.520687] RDX: 00007ffe30a57a30 RSI: 00000000ca289435 RDI: 0000000000000003 [162513.520689] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [162513.520690] R10: 0000000000000008 R11: 0000000000000202 R12: 0000000000000003 [162513.520692] R13: 0000557323a212e0 R14: 00007ffe30a5a520 R15: 0000000000000001 [162513.520703] Showing all locks held in the system: [162513.520712] 1 lock held by khungtaskd/54: [162513.520713] #0: ffffffffb40a91a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x197 [162513.520728] 1 lock held by in:imklog/596: [162513.520729] #0: ffff8f3f0d781400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x4d/0x60 [162513.520782] 1 lock held by btrfs-transacti/1356167: [162513.520784] #0: ffff8f3d810cc848 (&fs_info->transaction_kthread_mutex){+.+.}-{3:3}, at: transaction_kthread+0x4a/0x170 [btrfs] [162513.520798] 1 lock held by btrfs/1356190: [162513.520800] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write_file+0x22/0x60 [162513.520805] 1 lock held by fsstress/1356184: [162513.520806] #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0 [162513.520811] 3 locks held by fsstress/1356185: [162513.520812] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50 [162513.520815] #1: ffff8f3d80a650b8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: vfs_setxattr+0x50/0x120 [162513.520820] #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs] [162513.520833] 1 lock held by fsstress/1356196: [162513.520834] #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0 [162513.520838] 3 locks held by fsstress/1356197: [162513.520839] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50 [162513.520843] #1: ffff8f3d506465e8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: path_openat+0x2a7/0xa50 [162513.520846] #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs] [162513.520858] 2 locks held by btrfs/1356211: [162513.520859] #0: ffff8f3d810cde30 (&fs_info->dev_replace.lock_finishing_cancel_unmount){+.+.}-{3:3}, at: btrfs_dev_replace_finishing+0x52/0x711 [btrfs] [162513.520877] #1: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs] This was weird because the stack traces show that a transaction commit, triggered by a device replace operation, is blocking trying to pause any running scrubs but there are no stack traces of blocked tasks doing a scrub. After poking around with drgn, I noticed there was a scrub task that was constantly running and blocking for shorts periods of time: >>> t = find_task(prog, 1356190) >>> prog.stack_trace(t) #0 __schedule+0x5ce/0xcfc #1 schedule+0x46/0xe4 #2 schedule_timeout+0x1df/0x475 #3 btrfs_reada_wait+0xda/0x132 #4 scrub_stripe+0x2a8/0x112f #5 scrub_chunk+0xcd/0x134 #6 scrub_enumerate_chunks+0x29e/0x5ee #7 btrfs_scrub_dev+0x2d5/0x91b #8 btrfs_ioctl+0x7f5/0x36e7 #9 __x64_sys_ioctl+0x83/0xb0 torvalds#10 do_syscall_64+0x33/0x77 torvalds#11 entry_SYSCALL_64+0x7c/0x156 Which corresponds to: int btrfs_reada_wait(void *handle) { struct reada_control *rc = handle; struct btrfs_fs_info *fs_info = rc->fs_info; while (atomic_read(&rc->elems)) { if (!atomic_read(&fs_info->reada_works_cnt)) reada_start_machine(fs_info); wait_event_timeout(rc->wait, atomic_read(&rc->elems) == 0, (HZ + 9) / 10); } (...) So the counter "rc->elems" was set to 1 and never decreased to 0, causing the scrub task to loop forever in that function. Then I used the following script for drgn to check the readahead requests: $ cat dump_reada.py import sys import drgn from drgn import NULL, Object, cast, container_of, execscript, \ reinterpret, sizeof from drgn.helpers.linux import * mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1" mnt = None for mnt in for_each_mount(prog, dst = mnt_path): pass if mnt is None: sys.stderr.write(f'Error: mount point {mnt_path} not found\n') sys.exit(1) fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info) def dump_re(re): nzones = re.nzones.value_() print(f're at {hex(re.value_())}') print(f'\t logical {re.logical.value_()}') print(f'\t refcnt {re.refcnt.value_()}') print(f'\t nzones {nzones}') for i in range(nzones): dev = re.zones[i].device name = dev.name.str.string_() print(f'\t\t dev id {dev.devid.value_()} name {name}') print() for _, e in radix_tree_for_each(fs_info.reada_tree): re = cast('struct reada_extent *', e) dump_re(re) $ drgn dump_reada.py re at 0xffff8f3da9d25ad8 logical 38928384 refcnt 1 nzones 1 dev id 0 name b'/dev/sdd' $ So there was one readahead extent with a single zone corresponding to the source device of that last device replace operation logged in dmesg/syslog. Also the ID of that zone's device was 0 which is a special value set in the source device of a device replace operation when the operation finishes (constant BTRFS_DEV_REPLACE_DEVID set at btrfs_dev_replace_finishing()), confirming again that device /dev/sdd was the source of a device replace operation. Normally there should be as many zones in the readahead extent as there are devices, and I wasn't expecting the extent to be in a block group with a 'single' profile, so I went and confirmed with the following drgn script that there weren't any single profile block groups: $ cat dump_block_groups.py import sys import drgn from drgn import NULL, Object, cast, container_of, execscript, \ reinterpret, sizeof from drgn.helpers.linux import * mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1" mnt = None for mnt in for_each_mount(prog, dst = mnt_path): pass if mnt is None: sys.stderr.write(f'Error: mount point {mnt_path} not found\n') sys.exit(1) fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info) BTRFS_BLOCK_GROUP_DATA = (1 << 0) BTRFS_BLOCK_GROUP_SYSTEM = (1 << 1) BTRFS_BLOCK_GROUP_METADATA = (1 << 2) BTRFS_BLOCK_GROUP_RAID0 = (1 << 3) BTRFS_BLOCK_GROUP_RAID1 = (1 << 4) BTRFS_BLOCK_GROUP_DUP = (1 << 5) BTRFS_BLOCK_GROUP_RAID10 = (1 << 6) BTRFS_BLOCK_GROUP_RAID5 = (1 << 7) BTRFS_BLOCK_GROUP_RAID6 = (1 << 8) BTRFS_BLOCK_GROUP_RAID1C3 = (1 << 9) BTRFS_BLOCK_GROUP_RAID1C4 = (1 << 10) def bg_flags_string(bg): flags = bg.flags.value_() ret = '' if flags & BTRFS_BLOCK_GROUP_DATA: ret = 'data' if flags & BTRFS_BLOCK_GROUP_METADATA: if len(ret) > 0: ret += '|' ret += 'meta' if flags & BTRFS_BLOCK_GROUP_SYSTEM: if len(ret) > 0: ret += '|' ret += 'system' if flags & BTRFS_BLOCK_GROUP_RAID0: ret += ' raid0' elif flags & BTRFS_BLOCK_GROUP_RAID1: ret += ' raid1' elif flags & BTRFS_BLOCK_GROUP_DUP: ret += ' dup' elif flags & BTRFS_BLOCK_GROUP_RAID10: ret += ' raid10' elif flags & BTRFS_BLOCK_GROUP_RAID5: ret += ' raid5' elif flags & BTRFS_BLOCK_GROUP_RAID6: ret += ' raid6' elif flags & BTRFS_BLOCK_GROUP_RAID1C3: ret += ' raid1c3' elif flags & BTRFS_BLOCK_GROUP_RAID1C4: ret += ' raid1c4' else: ret += ' single' return ret def dump_bg(bg): print() print(f'block group at {hex(bg.value_())}') print(f'\t start {bg.start.value_()} length {bg.length.value_()}') print(f'\t flags {bg.flags.value_()} - {bg_flags_string(bg)}') bg_root = fs_info.block_group_cache_tree.address_of_() for bg in rbtree_inorder_for_each_entry('struct btrfs_block_group', bg_root, 'cache_node'): dump_bg(bg) $ drgn dump_block_groups.py block group at 0xffff8f3d673b0400 start 22020096 length 16777216 flags 258 - system raid6 block group at 0xffff8f3d53ddb400 start 38797312 length 536870912 flags 260 - meta raid6 block group at 0xffff8f3d5f4d9c00 start 575668224 length 2147483648 flags 257 - data raid6 block group at 0xffff8f3d08189000 start 2723151872 length 67108864 flags 258 - system raid6 block group at 0xffff8f3db70ff000 start 2790260736 length 1073741824 flags 260 - meta raid6 block group at 0xffff8f3d5f4dd800 start 3864002560 length 67108864 flags 258 - system raid6 block group at 0xffff8f3d67037000 start 3931111424 length 2147483648 flags 257 - data raid6 $ So there were only 2 reasons left for having a readahead extent with a single zone: reada_find_zone(), called when creating a readahead extent, returned NULL either because we failed to find the corresponding block group or because a memory allocation failed. With some additional and custom tracing I figured out that on every further ocurrence of the problem the block group had just been deleted when we were looping to create the zones for the readahead extent (at reada_find_extent()), so we ended up with only one zone in the readahead extent, corresponding to a device that ends up getting replaced. So after figuring that out it became obvious why the hang happens: 1) Task A starts a scrub on any device of the filesystem, except for device /dev/sdd; 2) Task B starts a device replace with /dev/sdd as the source device; 3) Task A calls btrfs_reada_add() from scrub_stripe() and it is currently starting to scrub a stripe from block group X. This call to btrfs_reada_add() is the one for the extent tree. When btrfs_reada_add() calls reada_add_block(), it passes the logical address of the extent tree's root node as its 'logical' argument - a value of 38928384; 4) Task A then enters reada_find_extent(), called from reada_add_block(). It finds there isn't any existing readahead extent for the logical address 38928384, so it proceeds to the path of creating a new one. It calls btrfs_map_block() to find out which stripes exist for the block group X. On the first iteration of the for loop that iterates over the stripes, it finds the stripe for device /dev/sdd, so it creates one zone for that device and adds it to the readahead extent. Before getting into the second iteration of the loop, the cleanup kthread deletes block group X because it was empty. So in the iterations for the remaining stripes it does not add more zones to the readahead extent, because the calls to reada_find_zone() returned NULL because they couldn't find block group X anymore. As a result the new readahead extent has a single zone, corresponding to the device /dev/sdd; 4) Before task A returns to btrfs_reada_add() and queues the readahead job for the readahead work queue, task B finishes the device replace and at btrfs_dev_replace_finishing() swaps the device /dev/sdd with the new device /dev/sdg; 5) Task A returns to reada_add_block(), which increments the counter "->elems" of the reada_control structure allocated at btrfs_reada_add(). Then it returns back to btrfs_reada_add() and calls reada_start_machine(). This queues a job in the readahead work queue to run the function reada_start_machine_worker(), which calls __reada_start_machine(). At __reada_start_machine() we take the device list mutex and for each device found in the current device list, we call reada_start_machine_dev() to start the readahead work. However at this point the device /dev/sdd was already freed and is not in the device list anymore. This means the corresponding readahead for the extent at 38928384 is never started, and therefore the "->elems" counter of the reada_control structure allocated at btrfs_reada_add() never goes down to 0, causing the call to btrfs_reada_wait(), done by the scrub task, to wait forever. Note that the readahead request can be made either after the device replace started or before it started, however in pratice it is very unlikely that a device replace is able to start after a readahead request is made and is able to complete before the readahead request completes - maybe only on a very small and nearly empty filesystem. This hang however is not the only problem we can have with readahead and device removals. When the readahead extent has other zones other than the one corresponding to the device that is being removed (either by a device replace or a device remove operation), we risk having a use-after-free on the device when dropping the last reference of the readahead extent. For example if we create a readahead extent with two zones, one for the device /dev/sdd and one for the device /dev/sde: 1) Before the readahead worker starts, the device /dev/sdd is removed, and the corresponding btrfs_device structure is freed. However the readahead extent still has the zone pointing to the device structure; 2) When the readahead worker starts, it only finds device /dev/sde in the current device list of the filesystem; 3) It starts the readahead work, at reada_start_machine_dev(), using the device /dev/sde; 4) Then when it finishes reading the extent from device /dev/sde, it calls __readahead_hook() which ends up dropping the last reference on the readahead extent through the last call to reada_extent_put(); 5) At reada_extent_put() it iterates over each zone of the readahead extent and attempts to delete an element from the device's 'reada_extents' radix tree, resulting in a use-after-free, as the device pointer of the zone for /dev/sdd is now stale. We can also access the device after dropping the last reference of a zone, through reada_zone_release(), also called by reada_extent_put(). And a device remove suffers the same problem, however since it shrinks the device size down to zero before removing the device, it is very unlikely to still have readahead requests not completed by the time we free the device, the only possibility is if the device has a very little space allocated. While the hang problem is exclusive to scrub, since it is currently the only user of btrfs_reada_add() and btrfs_reada_wait(), the use-after-free problem affects any path that triggers readhead, which includes btree_readahead_hook() and __readahead_hook() (a readahead worker can trigger readahed for the children of a node) for example - any path that ends up calling reada_add_block() can trigger the use-after-free after a device is removed. So fix this by waiting for any readahead requests for a device to complete before removing a device, ensuring that while waiting for existing ones no new ones can be made. This problem has been around for a very long time - the readahead code was added in 2011, device remove exists since 2008 and device replace was introduced in 2013, hard to pick a specific commit for a git Fixes tag. CC: [email protected] # 4.4+ Reviewed-by: Josef Bacik <[email protected]> Signed-off-by: Filipe Manana <[email protected]> Reviewed-by: David Sterba <[email protected]> Signed-off-by: David Sterba <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit e773ca7 ] Actually, burst size is equal to '1 << desc->rqcfg.brst_size'. we should use burst size, not desc->rqcfg.brst_size. dma memcpy performance on Rockchip RV1126 @ 1512MHz A7, 1056MHz LPDDR3, 200MHz DMA: dmatest: /# echo dma0chan0 > /sys/module/dmatest/parameters/channel /# echo 4194304 > /sys/module/dmatest/parameters/test_buf_size /# echo 8 > /sys/module/dmatest/parameters/iterations /# echo y > /sys/module/dmatest/parameters/norandom /# echo y > /sys/module/dmatest/parameters/verbose /# echo 1 > /sys/module/dmatest/parameters/run dmatest: dma0chan0-copy0: result #1: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #2: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #3: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #4: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #5: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #6: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #7: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #8: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 Before: dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 48 iops 200338 KB/s (0) After this patch: dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 179 iops 734873 KB/s (0) After this patch and increase dma clk to 400MHz: dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 259 iops 1062929 KB/s (0) Signed-off-by: Sugar Zhang <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Vinod Koul <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

mranostay and others added 30 commits May 24, 2013 10:44

cape: Added support for IIO helper cape

94672cd

Since we currently can't export the IIO channels from the ADCs this patch exposes an sysfs entry to read a respective channel. Signed-off-by: Matt Ranostay <[email protected]>

cape: Added example IIO tester dynamics overlay

fc3d5e6

Added an example usage of the IIO exporter for an current sensor reading. Scale factor works with INA169 current sensor at 10k load. Signed-off-by: Matt Ranostay <[email protected]>

docs: Added capemanager extra_override usage

dd7df69

Gave an example on using the kernel-command-line override slot options for capemanager. Signed-off-by: Matt Ranostay <[email protected]>

capemgr: Added module param descriptions

a564a5f

Added a simple MODULE_PARM_DESC for the extra_override option Signed-off-by: Matt Ranostay <[email protected]>

beaglebone: Add Adafruit RTC prototype cape

0736320

Add support for a DS1307 RTC prototype cape with level logic shifted output. Some applications need an early RTC value and this achieves this. Signed-off-by: Matt Ranostay <[email protected]>

cape: vsense-scale division by zero check

507e0c2

Catch corner case of division by zero when passing in vsense-scale property from the device tree. Signed-off-by: Matt Ranostay <[email protected]>

capes: add cape for beaglebone based Hexy robot

d5ca181

Signed-off-by: Koen Kooi <[email protected]>

Extend bone-iio helper

016e551

Allow multiple ADC entries. DT bindinds are extended so you can do: vsense-name = "AIN1", "AIN3"; vsense-scale = <100 100>; Signed-off-by: Pantelis Antoniou <[email protected]>

Update iio helper with more channels

6560d2f

Signed-off-by: Pantelis Antoniou <[email protected]>

Add ADC IIO helper

a749ff7

Changing DT data to make selection of standard (i.e. non-reduced blan…

25bdf3d

…king) modes the default

Enhancing to support extra device tree options for tilcdc: ti,max_wid…

5992202

…th (maximum width in pixels) ti,max_pixelclock (maximum allowable pixel clock for the device) also added some extra debugging enabled with drm debug to help understand why modes are being selected or rejected.

add WIP support LCD4 rev 00A4

956c2cf

Signed-off-by: Koen Kooi <[email protected]>

add eMMC cape support

56caf08

Signed-off-by: Koen Kooi <[email protected]>

Remove UART pins from the expansion set

ebcf247

Remove LCD pins from the expansion test part

4bae2c9

Remove I2C2 pins from expansion test

2c61347

It's too difficult for now to see how to test those. Temporarily take it out.

Add expansion test cape fragment.

60ba362

Not working yet, since more changes needed, but it's a start.

tilcdc added some extra debug, and softened the wording of the debug …

30d981b

…messages when deciding if a mode is supported or not

Make sure various timings fit within the bits available in the LCD co…

ac67bd7

…ntroller, otherwise prune the mode. Also adjust the timing values to behave as the TRM indicates with 0 representing 1 in some cases.

fix cape-bone-hexy

c222b12

Signed-off-by: Koen Kooi <[email protected]>

firmware: DT Fragment for MRF24J40 BeagleBone Cape

68fa26c

Support for the Signal 11 MRF24J40 BeagleBone Cape.

firmware: capes: Update MRF24J40 cape to work with latest bone dtsi

89f248f

am335x-bone-common.dtsi has removed the pinmux settings for SPI1. Add them to the MRF24J40 cape dts fragment Signed-off-by: Alan Ott <[email protected]>

am335x-bone-common: DT Override for MRF24J40 Cape

3cb3f20

Signed-off-by: Alan Ott <[email protected]>

beaglebone black: limit LDO3 to 1.8V

39d5a74

Signed-off-by: Koen Kooi <[email protected]>

beaglebone black: add new fixed regulator for uSD/eMMC

94785b3

Signed-off-by: Koen Kooi <[email protected]>

capemgr: Implement disable overrides on the cmd line

45939af

Allow capes to be disabled on the kernel command line. Signed-off-by: Pantelis Antoniou <[email protected]>

tilcdc: Enable pinmux states

256baf7

Things like the boot switch are on the LCD data pins. Allows us to change pinmuxing on runtime.

cape: Add a simple cape for handling the uSD button.

74c7b44

Doesn't work ofcourse due to conflict with the HDMI. Conflicts: firmware/Makefile

beaglebone: add support for DVI 00A3

19f5839

Signed-off-by: Koen Kooi <[email protected]>

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beaglebone: TT3201 CAN Bus Cape MCP2515 fixes #7

beaglebone: TT3201 CAN Bus Cape MCP2515 fixes #7

dwery commented May 23, 2013

beaglebone: TT3201 CAN Bus Cape MCP2515 fixes #7

Are you sure you want to change the base?

beaglebone: TT3201 CAN Bus Cape MCP2515 fixes #7

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dwery commented May 23, 2013