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ARM64: defconfig: enable several common USB network adapters #40

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@fboudra fboudra commented Apr 15, 2015

Signed-off-by: Fathi Boudra [email protected]

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ldts commented Apr 15, 2015

manually merged

@ldts ldts closed this Apr 15, 2015
johnstultz-work pushed a commit that referenced this pull request Nov 19, 2015
Multiple function in asynchronous hashing use a saved-state block,
a.k.a. struct caam_hash_state, which holds a stash of information
between requests (init/update/final). Certain values in this state
block are loaded for processing using an inline-if, and when this
is done, the potential for uninitialized data can pose conflicts.
Therefore, this patch improves initialization of state data to
prevent false assignments using uninitialized data in the state block.

This patch addresses the following traceback, originating in
ahash_final_ctx(), although a problem like this could certainly
exhibit other symptoms:

kernel BUG at arch/arm/mm/dma-mapping.c:465!
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = 80004000
[00000000] *pgd=00000000
Internal error: Oops: 805 [#1] PREEMPT SMP
Modules linked in:
CPU: 0    Not tainted  (3.0.15-01752-gdd441b9-dirty #40)
PC is at __bug+0x1c/0x28
LR is at __bug+0x18/0x28
pc : [<80043240>]    lr : [<8004323c>]    psr: 60000013
sp : e423fd98  ip : 60000013  fp : 0000001c
r10: e4191b84  r9 : 00000020  r8 : 00000009
r7 : 88005038  r6 : 00000001  r5 : 2d676572  r4 : e4191a60
r3 : 00000000  r2 : 00000001  r1 : 60000093  r0 : 00000033
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c53c7d  Table: 1000404a  DAC: 00000015
Process cryptomgr_test (pid: 1306, stack limit = 0xe423e2f0)
Stack: (0xe423fd98 to 0xe4240000)
fd80:                                                       11807fd1 80048544
fda0: 88005000 e4191a00 e5178040 8039dda0 00000000 00000014 2d676572 e419100
fdc0: 88005018 e4191a60 00100100 e4191a00 00000000 8039ce0c e423fea8 00000007
fde0: e4191a00 e4227000 e5178000 8039ce18 e419183c 80203808 80a94a44 00000006
fe00: 00000000 80207180 00000000 00000006 e423ff08 00000000 00000007 e5178000
fe20: e41918a4 80a949b4 8c4844e2 00000000 00000049 74227000 8c4844e2 00000e90
fe40: 0000000e 74227e90 ffff8c58 80ac29e0 e423fed4 8006a350 8c81625c e423ff5c
fe60: 00008576 e4002500 00000003 00030010 e4002500 00000003 e5180000 e4002500
fe80: e5178000 800e6d24 007fffff 00000000 00000010 e4001280 e4002500 60000013
fea0: 000000d0 804df078 00000000 00000000 00000000 00000000 00000000 00000000
fec0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
fee0: 00000000 00000000 e4227000 e4226000 e4753000 e4752000 e40a5000 e40a4000
ff00: e41e7000 e41e6000 00000000 00000000 00000000 e423ff14 e423ff14 00000000
ff20: 00000400 804f9080 e5178000 e4db0b40 00000000 e4db0b80 0000047c 00000400
ff40: 00000000 8020758c 00000400 ffffffff 0000008a 00000000 e4db0b40 80206e00
ff60: e4049dbc 00000000 00000000 00000003 e423ffa4 80062978 e41a8bfc 00000000
ff80: 00000000 e4049db4 00000013 e4049db0 00000013 00000000 00000000 00000000
ffa0: e4db0b40 e4db0b40 80204cbc 00000013 00000000 00000000 00000000 80204cfc
ffc0: e4049da0 80089544 80040a40 00000000 e4db0b40 00000000 00000000 00000000
ffe0: e423ffe0 e423ffe0 e4049da0 800894c4 80040a40 80040a40 00000000 00000000
[<80043240>] (__bug+0x1c/0x28) from [<80048544>] (___dma_single_dev_to_cpu+0x84)
[<80048544>] (___dma_single_dev_to_cpu+0x84/0x94) from [<8039dda0>] (ahash_fina)
[<8039dda0>] (ahash_final_ctx+0x180/0x428) from [<8039ce18>] (ahash_final+0xc/0)
[<8039ce18>] (ahash_final+0xc/0x10) from [<80203808>] (crypto_ahash_op+0x28/0xc)
[<80203808>] (crypto_ahash_op+0x28/0xc0) from [<80207180>] (test_hash+0x214/0x5)
[<80207180>] (test_hash+0x214/0x5b8) from [<8020758c>] (alg_test_hash+0x68/0x8c)
[<8020758c>] (alg_test_hash+0x68/0x8c) from [<80206e00>] (alg_test+0x7c/0x1b8)
[<80206e00>] (alg_test+0x7c/0x1b8) from [<80204cfc>] (cryptomgr_test+0x40/0x48)
[<80204cfc>] (cryptomgr_test+0x40/0x48) from [<80089544>] (kthread+0x80/0x88)
[<80089544>] (kthread+0x80/0x88) from [<80040a40>] (kernel_thread_exit+0x0/0x8)
Code: e59f0010 e1a01003 eb126a8d e3a03000 (e5833000)
---[ end trace d52a403a1d1eaa86 ]---

Cc: [email protected]
Signed-off-by: Steve Cornelius <[email protected]>
Signed-off-by: Victoria Milhoan <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
johnstultz-work pushed a commit that referenced this pull request Jan 5, 2016
commit ecf5fc6 upstream.

Nikolay has reported a hang when a memcg reclaim got stuck with the
following backtrace:

PID: 18308  TASK: ffff883d7c9b0a30  CPU: 1   COMMAND: "rsync"
  #0 __schedule at ffffffff815ab152
  #1 schedule at ffffffff815ab76e
  #2 schedule_timeout at ffffffff815ae5e5
  #3 io_schedule_timeout at ffffffff815aad6a
  #4 bit_wait_io at ffffffff815abfc6
  #5 __wait_on_bit at ffffffff815abda5
  #6 wait_on_page_bit at ffffffff8111fd4f
  #7 shrink_page_list at ffffffff81135445
  #8 shrink_inactive_list at ffffffff81135845
  #9 shrink_lruvec at ffffffff81135ead
 #10 shrink_zone at ffffffff811360c3
 #11 shrink_zones at ffffffff81136eff
 #12 do_try_to_free_pages at ffffffff8113712f
 #13 try_to_free_mem_cgroup_pages at ffffffff811372be
 #14 try_charge at ffffffff81189423
 #15 mem_cgroup_try_charge at ffffffff8118c6f5
 #16 __add_to_page_cache_locked at ffffffff8112137d
 #17 add_to_page_cache_lru at ffffffff81121618
 #18 pagecache_get_page at ffffffff8112170b
 #19 grow_dev_page at ffffffff811c8297
 #20 __getblk_slow at ffffffff811c91d6
 #21 __getblk_gfp at ffffffff811c92c1
 #22 ext4_ext_grow_indepth at ffffffff8124565c
 #23 ext4_ext_create_new_leaf at ffffffff81246ca8
 #24 ext4_ext_insert_extent at ffffffff81246f09
 #25 ext4_ext_map_blocks at ffffffff8124a848
 #26 ext4_map_blocks at ffffffff8121a5b7
 #27 mpage_map_one_extent at ffffffff8121b1fa
 #28 mpage_map_and_submit_extent at ffffffff8121f07b
 #29 ext4_writepages at ffffffff8121f6d5
 #30 do_writepages at ffffffff8112c490
 #31 __filemap_fdatawrite_range at ffffffff81120199
 #32 filemap_flush at ffffffff8112041c
 #33 ext4_alloc_da_blocks at ffffffff81219da1
 #34 ext4_rename at ffffffff81229b91
 #35 ext4_rename2 at ffffffff81229e32
 #36 vfs_rename at ffffffff811a08a5
 #37 SYSC_renameat2 at ffffffff811a3ffc
 #38 sys_renameat2 at ffffffff811a408e
 #39 sys_rename at ffffffff8119e51e
 #40 system_call_fastpath at ffffffff815afa89

Dave Chinner has properly pointed out that this is a deadlock in the
reclaim code because ext4 doesn't submit pages which are marked by
PG_writeback right away.

The heuristic was introduced by commit e62e384 ("memcg: prevent OOM
with too many dirty pages") and it was applied only when may_enter_fs
was specified.  The code has been changed by c3b94f4 ("memcg:
further prevent OOM with too many dirty pages") which has removed the
__GFP_FS restriction with a reasoning that we do not get into the fs
code.  But this is not sufficient apparently because the fs doesn't
necessarily submit pages marked PG_writeback for IO right away.

ext4_bio_write_page calls io_submit_add_bh but that doesn't necessarily
submit the bio.  Instead it tries to map more pages into the bio and
mpage_map_one_extent might trigger memcg charge which might end up
waiting on a page which is marked PG_writeback but hasn't been submitted
yet so we would end up waiting for something that never finishes.

Fix this issue by replacing __GFP_IO by may_enter_fs check (for case 2)
before we go to wait on the writeback.  The page fault path, which is
the only path that triggers memcg oom killer since 3.12, shouldn't
require GFP_NOFS and so we shouldn't reintroduce the premature OOM
killer issue which was originally addressed by the heuristic.

As per David Chinner the xfs is doing similar thing since 2.6.15 already
so ext4 is not the only affected filesystem.  Moreover he notes:

: For example: IO completion might require unwritten extent conversion
: which executes filesystem transactions and GFP_NOFS allocations. The
: writeback flag on the pages can not be cleared until unwritten
: extent conversion completes. Hence memory reclaim cannot wait on
: page writeback to complete in GFP_NOFS context because it is not
: safe to do so, memcg reclaim or otherwise.

Cc: [email protected] # 3.9+
[[email protected]: corrected the control flow]
Fixes: c3b94f4 ("memcg: further prevent OOM with too many dirty pages")
Reported-by: Nikolay Borisov <[email protected]>
Signed-off-by: Michal Hocko <[email protected]>
Signed-off-by: Hugh Dickins <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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