Merge pull request #1 from torvalds/master #123

rakesh-gopal · 2014-09-19T06:16:38Z

pulling latest linux code

Fix driver new_id sysfs-attribute removal deadlock by making sure to not hold any locks that the attribute operations grab when removing the attribute. Specifically, usb_serial_deregister holds the table mutex when deregistering the driver, which includes removing the new_id attribute. This can lead to a deadlock as writing to new_id increments the attribute's active count before trying to grab the same mutex in usb_serial_probe. The deadlock can easily be triggered by inserting a sleep in usb_serial_deregister and writing the id of an unbound device to new_id during module unload. As the table mutex (in this case) is used to prevent subdriver unload during probe, it should be sufficient to only hold the lock while manipulating the usb-serial driver list during deregister. A racing probe will then either fail to find a matching subdriver or fail to get the corresponding module reference. Since v3.15-rc1 this also triggers the following lockdep warning: ====================================================== [ INFO: possible circular locking dependency detected ] 3.15.0-rc2 torvalds#123 Tainted: G W ------------------------------------------------------- modprobe/190 is trying to acquire lock: (s_active#4){++++.+}, at: [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 but task is already holding lock: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (table_lock){+.+.+.}: [<c0075f84>] __lock_acquire+0x1694/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c03af3cc>] _raw_spin_lock+0x4c/0x5c [<c02bbc24>] usb_store_new_id+0x14c/0x1ac [<bf007eb4>] new_id_store+0x68/0x70 [usbserial] [<c025f568>] drv_attr_store+0x30/0x3c [<c01690e0>] sysfs_kf_write+0x5c/0x60 [<c01682c0>] kernfs_fop_write+0xd4/0x194 [<c010881c>] vfs_write+0xbc/0x198 [<c0108e4c>] SyS_write+0x4c/0xa0 [<c000f880>] ret_fast_syscall+0x0/0x48 -> #0 (s_active#4){++++.+}: [<c03a7a28>] print_circular_bug+0x68/0x2f8 [<c0076218>] __lock_acquire+0x1928/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c0166b70>] __kernfs_remove+0x254/0x310 [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 [<c0169fb8>] remove_files.isra.1+0x48/0x84 [<c016a2fc>] sysfs_remove_group+0x58/0xac [<c016a414>] sysfs_remove_groups+0x34/0x44 [<c02623b8>] driver_remove_groups+0x1c/0x20 [<c0260e9c>] bus_remove_driver+0x3c/0xe4 [<c026235c>] driver_unregister+0x38/0x58 [<bf007fb4>] usb_serial_bus_deregister+0x84/0x88 [usbserial] [<bf004db4>] usb_serial_deregister+0x6c/0x78 [usbserial] [<bf005330>] usb_serial_deregister_drivers+0x2c/0x4c [usbserial] [<bf016618>] usb_serial_module_exit+0x14/0x1c [sierra] [<c009d6cc>] SyS_delete_module+0x184/0x210 [<c000f880>] ret_fast_syscall+0x0/0x48 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(table_lock); lock(s_active#4); lock(table_lock); lock(s_active#4); *** DEADLOCK *** 1 lock held by modprobe/190: #0: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] stack backtrace: CPU: 0 PID: 190 Comm: modprobe Tainted: G W 3.15.0-rc2 torvalds#123 [<c0015e10>] (unwind_backtrace) from [<c0013728>] (show_stack+0x20/0x24) [<c0013728>] (show_stack) from [<c03a9a54>] (dump_stack+0x24/0x28) [<c03a9a54>] (dump_stack) from [<c03a7cac>] (print_circular_bug+0x2ec/0x2f8) [<c03a7cac>] (print_circular_bug) from [<c0076218>] (__lock_acquire+0x1928/0x1ce4) [<c0076218>] (__lock_acquire) from [<c0076de8>] (lock_acquire+0xb4/0x154) [<c0076de8>] (lock_acquire) from [<c0166b70>] (__kernfs_remove+0x254/0x310) [<c0166b70>] (__kernfs_remove) from [<c0167aa0>] (kernfs_remove_by_name_ns+0x4c/0x94) [<c0167aa0>] (kernfs_remove_by_name_ns) from [<c0169fb8>] (remove_files.isra.1+0x48/0x84) [<c0169fb8>] (remove_files.isra.1) from [<c016a2fc>] (sysfs_remove_group+0x58/0xac) [<c016a2fc>] (sysfs_remove_group) from [<c016a414>] (sysfs_remove_groups+0x34/0x44) [<c016a414>] (sysfs_remove_groups) from [<c02623b8>] (driver_remove_groups+0x1c/0x20) [<c02623b8>] (driver_remove_groups) from [<c0260e9c>] (bus_remove_driver+0x3c/0xe4) [<c0260e9c>] (bus_remove_driver) from [<c026235c>] (driver_unregister+0x38/0x58) [<c026235c>] (driver_unregister) from [<bf007fb4>] (usb_serial_bus_deregister+0x84/0x88 [usbserial]) [<bf007fb4>] (usb_serial_bus_deregister [usbserial]) from [<bf004db4>] (usb_serial_deregister+0x6c/0x78 [usbserial]) [<bf004db4>] (usb_serial_deregister [usbserial]) from [<bf005330>] (usb_serial_deregister_drivers+0x2c/0x4c [usbserial]) [<bf005330>] (usb_serial_deregister_drivers [usbserial]) from [<bf016618>] (usb_serial_module_exit+0x14/0x1c [sierra]) [<bf016618>] (usb_serial_module_exit [sierra]) from [<c009d6cc>] (SyS_delete_module+0x184/0x210) [<c009d6cc>] (SyS_delete_module) from [<c000f880>] (ret_fast_syscall+0x0/0x48) Signed-off-by: Johan Hovold <[email protected]> Cc: stable <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit 10164c2 upstream. Fix driver new_id sysfs-attribute removal deadlock by making sure to not hold any locks that the attribute operations grab when removing the attribute. Specifically, usb_serial_deregister holds the table mutex when deregistering the driver, which includes removing the new_id attribute. This can lead to a deadlock as writing to new_id increments the attribute's active count before trying to grab the same mutex in usb_serial_probe. The deadlock can easily be triggered by inserting a sleep in usb_serial_deregister and writing the id of an unbound device to new_id during module unload. As the table mutex (in this case) is used to prevent subdriver unload during probe, it should be sufficient to only hold the lock while manipulating the usb-serial driver list during deregister. A racing probe will then either fail to find a matching subdriver or fail to get the corresponding module reference. Since v3.15-rc1 this also triggers the following lockdep warning: ====================================================== [ INFO: possible circular locking dependency detected ] 3.15.0-rc2 torvalds#123 Tainted: G W ------------------------------------------------------- modprobe/190 is trying to acquire lock: (s_active#4){++++.+}, at: [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 but task is already holding lock: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (table_lock){+.+.+.}: [<c0075f84>] __lock_acquire+0x1694/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c03af3cc>] _raw_spin_lock+0x4c/0x5c [<c02bbc24>] usb_store_new_id+0x14c/0x1ac [<bf007eb4>] new_id_store+0x68/0x70 [usbserial] [<c025f568>] drv_attr_store+0x30/0x3c [<c01690e0>] sysfs_kf_write+0x5c/0x60 [<c01682c0>] kernfs_fop_write+0xd4/0x194 [<c010881c>] vfs_write+0xbc/0x198 [<c0108e4c>] SyS_write+0x4c/0xa0 [<c000f880>] ret_fast_syscall+0x0/0x48 -> #0 (s_active#4){++++.+}: [<c03a7a28>] print_circular_bug+0x68/0x2f8 [<c0076218>] __lock_acquire+0x1928/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c0166b70>] __kernfs_remove+0x254/0x310 [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 [<c0169fb8>] remove_files.isra.1+0x48/0x84 [<c016a2fc>] sysfs_remove_group+0x58/0xac [<c016a414>] sysfs_remove_groups+0x34/0x44 [<c02623b8>] driver_remove_groups+0x1c/0x20 [<c0260e9c>] bus_remove_driver+0x3c/0xe4 [<c026235c>] driver_unregister+0x38/0x58 [<bf007fb4>] usb_serial_bus_deregister+0x84/0x88 [usbserial] [<bf004db4>] usb_serial_deregister+0x6c/0x78 [usbserial] [<bf005330>] usb_serial_deregister_drivers+0x2c/0x4c [usbserial] [<bf016618>] usb_serial_module_exit+0x14/0x1c [sierra] [<c009d6cc>] SyS_delete_module+0x184/0x210 [<c000f880>] ret_fast_syscall+0x0/0x48 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(table_lock); lock(s_active#4); lock(table_lock); lock(s_active#4); *** DEADLOCK *** 1 lock held by modprobe/190: #0: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] stack backtrace: CPU: 0 PID: 190 Comm: modprobe Tainted: G W 3.15.0-rc2 torvalds#123 [<c0015e10>] (unwind_backtrace) from [<c0013728>] (show_stack+0x20/0x24) [<c0013728>] (show_stack) from [<c03a9a54>] (dump_stack+0x24/0x28) [<c03a9a54>] (dump_stack) from [<c03a7cac>] (print_circular_bug+0x2ec/0x2f8) [<c03a7cac>] (print_circular_bug) from [<c0076218>] (__lock_acquire+0x1928/0x1ce4) [<c0076218>] (__lock_acquire) from [<c0076de8>] (lock_acquire+0xb4/0x154) [<c0076de8>] (lock_acquire) from [<c0166b70>] (__kernfs_remove+0x254/0x310) [<c0166b70>] (__kernfs_remove) from [<c0167aa0>] (kernfs_remove_by_name_ns+0x4c/0x94) [<c0167aa0>] (kernfs_remove_by_name_ns) from [<c0169fb8>] (remove_files.isra.1+0x48/0x84) [<c0169fb8>] (remove_files.isra.1) from [<c016a2fc>] (sysfs_remove_group+0x58/0xac) [<c016a2fc>] (sysfs_remove_group) from [<c016a414>] (sysfs_remove_groups+0x34/0x44) [<c016a414>] (sysfs_remove_groups) from [<c02623b8>] (driver_remove_groups+0x1c/0x20) [<c02623b8>] (driver_remove_groups) from [<c0260e9c>] (bus_remove_driver+0x3c/0xe4) [<c0260e9c>] (bus_remove_driver) from [<c026235c>] (driver_unregister+0x38/0x58) [<c026235c>] (driver_unregister) from [<bf007fb4>] (usb_serial_bus_deregister+0x84/0x88 [usbserial]) [<bf007fb4>] (usb_serial_bus_deregister [usbserial]) from [<bf004db4>] (usb_serial_deregister+0x6c/0x78 [usbserial]) [<bf004db4>] (usb_serial_deregister [usbserial]) from [<bf005330>] (usb_serial_deregister_drivers+0x2c/0x4c [usbserial]) [<bf005330>] (usb_serial_deregister_drivers [usbserial]) from [<bf016618>] (usb_serial_module_exit+0x14/0x1c [sierra]) [<bf016618>] (usb_serial_module_exit [sierra]) from [<c009d6cc>] (SyS_delete_module+0x184/0x210) [<c009d6cc>] (SyS_delete_module) from [<c000f880>] (ret_fast_syscall+0x0/0x48) Signed-off-by: Johan Hovold <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

Fix driver new_id sysfs-attribute removal deadlock by making sure to not hold any locks that the attribute operations grab when removing the attribute. Specifically, usb_serial_deregister holds the table mutex when deregistering the driver, which includes removing the new_id attribute. This can lead to a deadlock as writing to new_id increments the attribute's active count before trying to grab the same mutex in usb_serial_probe. The deadlock can easily be triggered by inserting a sleep in usb_serial_deregister and writing the id of an unbound device to new_id during module unload. As the table mutex (in this case) is used to prevent subdriver unload during probe, it should be sufficient to only hold the lock while manipulating the usb-serial driver list during deregister. A racing probe will then either fail to find a matching subdriver or fail to get the corresponding module reference. Since v3.15-rc1 this also triggers the following lockdep warning: ====================================================== [ INFO: possible circular locking dependency detected ] 3.15.0-rc2 torvalds#123 Tainted: G W ------------------------------------------------------- modprobe/190 is trying to acquire lock: (s_active#4){++++.+}, at: [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 but task is already holding lock: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (table_lock){+.+.+.}: [<c0075f84>] __lock_acquire+0x1694/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c03af3cc>] _raw_spin_lock+0x4c/0x5c [<c02bbc24>] usb_store_new_id+0x14c/0x1ac [<bf007eb4>] new_id_store+0x68/0x70 [usbserial] [<c025f568>] drv_attr_store+0x30/0x3c [<c01690e0>] sysfs_kf_write+0x5c/0x60 [<c01682c0>] kernfs_fop_write+0xd4/0x194 [<c010881c>] vfs_write+0xbc/0x198 [<c0108e4c>] SyS_write+0x4c/0xa0 [<c000f880>] ret_fast_syscall+0x0/0x48 -> #0 (s_active#4){++++.+}: [<c03a7a28>] print_circular_bug+0x68/0x2f8 [<c0076218>] __lock_acquire+0x1928/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c0166b70>] __kernfs_remove+0x254/0x310 [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 [<c0169fb8>] remove_files.isra.1+0x48/0x84 [<c016a2fc>] sysfs_remove_group+0x58/0xac [<c016a414>] sysfs_remove_groups+0x34/0x44 [<c02623b8>] driver_remove_groups+0x1c/0x20 [<c0260e9c>] bus_remove_driver+0x3c/0xe4 [<c026235c>] driver_unregister+0x38/0x58 [<bf007fb4>] usb_serial_bus_deregister+0x84/0x88 [usbserial] [<bf004db4>] usb_serial_deregister+0x6c/0x78 [usbserial] [<bf005330>] usb_serial_deregister_drivers+0x2c/0x4c [usbserial] [<bf016618>] usb_serial_module_exit+0x14/0x1c [sierra] [<c009d6cc>] SyS_delete_module+0x184/0x210 [<c000f880>] ret_fast_syscall+0x0/0x48 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(table_lock); lock(s_active#4); lock(table_lock); lock(s_active#4); *** DEADLOCK *** 1 lock held by modprobe/190: #0: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] stack backtrace: CPU: 0 PID: 190 Comm: modprobe Tainted: G W 3.15.0-rc2 torvalds#123 [<c0015e10>] (unwind_backtrace) from [<c0013728>] (show_stack+0x20/0x24) [<c0013728>] (show_stack) from [<c03a9a54>] (dump_stack+0x24/0x28) [<c03a9a54>] (dump_stack) from [<c03a7cac>] (print_circular_bug+0x2ec/0x2f8) [<c03a7cac>] (print_circular_bug) from [<c0076218>] (__lock_acquire+0x1928/0x1ce4) [<c0076218>] (__lock_acquire) from [<c0076de8>] (lock_acquire+0xb4/0x154) [<c0076de8>] (lock_acquire) from [<c0166b70>] (__kernfs_remove+0x254/0x310) [<c0166b70>] (__kernfs_remove) from [<c0167aa0>] (kernfs_remove_by_name_ns+0x4c/0x94) [<c0167aa0>] (kernfs_remove_by_name_ns) from [<c0169fb8>] (remove_files.isra.1+0x48/0x84) [<c0169fb8>] (remove_files.isra.1) from [<c016a2fc>] (sysfs_remove_group+0x58/0xac) [<c016a2fc>] (sysfs_remove_group) from [<c016a414>] (sysfs_remove_groups+0x34/0x44) [<c016a414>] (sysfs_remove_groups) from [<c02623b8>] (driver_remove_groups+0x1c/0x20) [<c02623b8>] (driver_remove_groups) from [<c0260e9c>] (bus_remove_driver+0x3c/0xe4) [<c0260e9c>] (bus_remove_driver) from [<c026235c>] (driver_unregister+0x38/0x58) [<c026235c>] (driver_unregister) from [<bf007fb4>] (usb_serial_bus_deregister+0x84/0x88 [usbserial]) [<bf007fb4>] (usb_serial_bus_deregister [usbserial]) from [<bf004db4>] (usb_serial_deregister+0x6c/0x78 [usbserial]) [<bf004db4>] (usb_serial_deregister [usbserial]) from [<bf005330>] (usb_serial_deregister_drivers+0x2c/0x4c [usbserial]) [<bf005330>] (usb_serial_deregister_drivers [usbserial]) from [<bf016618>] (usb_serial_module_exit+0x14/0x1c [sierra]) [<bf016618>] (usb_serial_module_exit [sierra]) from [<c009d6cc>] (SyS_delete_module+0x184/0x210) [<c009d6cc>] (SyS_delete_module) from [<c000f880>] (ret_fast_syscall+0x0/0x48) Signed-off-by: Johan Hovold <[email protected]> Cc: stable <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit 10164c2 upstream. Fix driver new_id sysfs-attribute removal deadlock by making sure to not hold any locks that the attribute operations grab when removing the attribute. Specifically, usb_serial_deregister holds the table mutex when deregistering the driver, which includes removing the new_id attribute. This can lead to a deadlock as writing to new_id increments the attribute's active count before trying to grab the same mutex in usb_serial_probe. The deadlock can easily be triggered by inserting a sleep in usb_serial_deregister and writing the id of an unbound device to new_id during module unload. As the table mutex (in this case) is used to prevent subdriver unload during probe, it should be sufficient to only hold the lock while manipulating the usb-serial driver list during deregister. A racing probe will then either fail to find a matching subdriver or fail to get the corresponding module reference. Since v3.15-rc1 this also triggers the following lockdep warning: ====================================================== [ INFO: possible circular locking dependency detected ] 3.15.0-rc2 hardkernel#123 Tainted: G W ------------------------------------------------------- modprobe/190 is trying to acquire lock: (s_active#4){++++.+}, at: [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 but task is already holding lock: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (table_lock){+.+.+.}: [<c0075f84>] __lock_acquire+0x1694/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c03af3cc>] _raw_spin_lock+0x4c/0x5c [<c02bbc24>] usb_store_new_id+0x14c/0x1ac [<bf007eb4>] new_id_store+0x68/0x70 [usbserial] [<c025f568>] drv_attr_store+0x30/0x3c [<c01690e0>] sysfs_kf_write+0x5c/0x60 [<c01682c0>] kernfs_fop_write+0xd4/0x194 [<c010881c>] vfs_write+0xbc/0x198 [<c0108e4c>] SyS_write+0x4c/0xa0 [<c000f880>] ret_fast_syscall+0x0/0x48 -> #0 (s_active#4){++++.+}: [<c03a7a28>] print_circular_bug+0x68/0x2f8 [<c0076218>] __lock_acquire+0x1928/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c0166b70>] __kernfs_remove+0x254/0x310 [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 [<c0169fb8>] remove_files.isra.1+0x48/0x84 [<c016a2fc>] sysfs_remove_group+0x58/0xac [<c016a414>] sysfs_remove_groups+0x34/0x44 [<c02623b8>] driver_remove_groups+0x1c/0x20 [<c0260e9c>] bus_remove_driver+0x3c/0xe4 [<c026235c>] driver_unregister+0x38/0x58 [<bf007fb4>] usb_serial_bus_deregister+0x84/0x88 [usbserial] [<bf004db4>] usb_serial_deregister+0x6c/0x78 [usbserial] [<bf005330>] usb_serial_deregister_drivers+0x2c/0x4c [usbserial] [<bf016618>] usb_serial_module_exit+0x14/0x1c [sierra] [<c009d6cc>] SyS_delete_module+0x184/0x210 [<c000f880>] ret_fast_syscall+0x0/0x48 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(table_lock); lock(s_active#4); lock(table_lock); lock(s_active#4); *** DEADLOCK *** 1 lock held by modprobe/190: #0: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] stack backtrace: CPU: 0 PID: 190 Comm: modprobe Tainted: G W 3.15.0-rc2 hardkernel#123 [<c0015e10>] (unwind_backtrace) from [<c0013728>] (show_stack+0x20/0x24) [<c0013728>] (show_stack) from [<c03a9a54>] (dump_stack+0x24/0x28) [<c03a9a54>] (dump_stack) from [<c03a7cac>] (print_circular_bug+0x2ec/0x2f8) [<c03a7cac>] (print_circular_bug) from [<c0076218>] (__lock_acquire+0x1928/0x1ce4) [<c0076218>] (__lock_acquire) from [<c0076de8>] (lock_acquire+0xb4/0x154) [<c0076de8>] (lock_acquire) from [<c0166b70>] (__kernfs_remove+0x254/0x310) [<c0166b70>] (__kernfs_remove) from [<c0167aa0>] (kernfs_remove_by_name_ns+0x4c/0x94) [<c0167aa0>] (kernfs_remove_by_name_ns) from [<c0169fb8>] (remove_files.isra.1+0x48/0x84) [<c0169fb8>] (remove_files.isra.1) from [<c016a2fc>] (sysfs_remove_group+0x58/0xac) [<c016a2fc>] (sysfs_remove_group) from [<c016a414>] (sysfs_remove_groups+0x34/0x44) [<c016a414>] (sysfs_remove_groups) from [<c02623b8>] (driver_remove_groups+0x1c/0x20) [<c02623b8>] (driver_remove_groups) from [<c0260e9c>] (bus_remove_driver+0x3c/0xe4) [<c0260e9c>] (bus_remove_driver) from [<c026235c>] (driver_unregister+0x38/0x58) [<c026235c>] (driver_unregister) from [<bf007fb4>] (usb_serial_bus_deregister+0x84/0x88 [usbserial]) [<bf007fb4>] (usb_serial_bus_deregister [usbserial]) from [<bf004db4>] (usb_serial_deregister+0x6c/0x78 [usbserial]) [<bf004db4>] (usb_serial_deregister [usbserial]) from [<bf005330>] (usb_serial_deregister_drivers+0x2c/0x4c [usbserial]) [<bf005330>] (usb_serial_deregister_drivers [usbserial]) from [<bf016618>] (usb_serial_module_exit+0x14/0x1c [sierra]) [<bf016618>] (usb_serial_module_exit [sierra]) from [<c009d6cc>] (SyS_delete_module+0x184/0x210) [<c009d6cc>] (SyS_delete_module) from [<c000f880>] (ret_fast_syscall+0x0/0x48) Signed-off-by: Johan Hovold <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> Signed-off-by: Kamal Mostafa <[email protected]>

commit 10164c2 upstream. Fix driver new_id sysfs-attribute removal deadlock by making sure to not hold any locks that the attribute operations grab when removing the attribute. Specifically, usb_serial_deregister holds the table mutex when deregistering the driver, which includes removing the new_id attribute. This can lead to a deadlock as writing to new_id increments the attribute's active count before trying to grab the same mutex in usb_serial_probe. The deadlock can easily be triggered by inserting a sleep in usb_serial_deregister and writing the id of an unbound device to new_id during module unload. As the table mutex (in this case) is used to prevent subdriver unload during probe, it should be sufficient to only hold the lock while manipulating the usb-serial driver list during deregister. A racing probe will then either fail to find a matching subdriver or fail to get the corresponding module reference. Since v3.15-rc1 this also triggers the following lockdep warning: ====================================================== [ INFO: possible circular locking dependency detected ] 3.15.0-rc2 torvalds#123 Tainted: G W ------------------------------------------------------- modprobe/190 is trying to acquire lock: (s_active#4){++++.+}, at: [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 but task is already holding lock: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (table_lock){+.+.+.}: [<c0075f84>] __lock_acquire+0x1694/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c03af3cc>] _raw_spin_lock+0x4c/0x5c [<c02bbc24>] usb_store_new_id+0x14c/0x1ac [<bf007eb4>] new_id_store+0x68/0x70 [usbserial] [<c025f568>] drv_attr_store+0x30/0x3c [<c01690e0>] sysfs_kf_write+0x5c/0x60 [<c01682c0>] kernfs_fop_write+0xd4/0x194 [<c010881c>] vfs_write+0xbc/0x198 [<c0108e4c>] SyS_write+0x4c/0xa0 [<c000f880>] ret_fast_syscall+0x0/0x48 -> #0 (s_active#4){++++.+}: [<c03a7a28>] print_circular_bug+0x68/0x2f8 [<c0076218>] __lock_acquire+0x1928/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c0166b70>] __kernfs_remove+0x254/0x310 [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 [<c0169fb8>] remove_files.isra.1+0x48/0x84 [<c016a2fc>] sysfs_remove_group+0x58/0xac [<c016a414>] sysfs_remove_groups+0x34/0x44 [<c02623b8>] driver_remove_groups+0x1c/0x20 [<c0260e9c>] bus_remove_driver+0x3c/0xe4 [<c026235c>] driver_unregister+0x38/0x58 [<bf007fb4>] usb_serial_bus_deregister+0x84/0x88 [usbserial] [<bf004db4>] usb_serial_deregister+0x6c/0x78 [usbserial] [<bf005330>] usb_serial_deregister_drivers+0x2c/0x4c [usbserial] [<bf016618>] usb_serial_module_exit+0x14/0x1c [sierra] [<c009d6cc>] SyS_delete_module+0x184/0x210 [<c000f880>] ret_fast_syscall+0x0/0x48 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(table_lock); lock(s_active#4); lock(table_lock); lock(s_active#4); *** DEADLOCK *** 1 lock held by modprobe/190: #0: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] stack backtrace: CPU: 0 PID: 190 Comm: modprobe Tainted: G W 3.15.0-rc2 torvalds#123 [<c0015e10>] (unwind_backtrace) from [<c0013728>] (show_stack+0x20/0x24) [<c0013728>] (show_stack) from [<c03a9a54>] (dump_stack+0x24/0x28) [<c03a9a54>] (dump_stack) from [<c03a7cac>] (print_circular_bug+0x2ec/0x2f8) [<c03a7cac>] (print_circular_bug) from [<c0076218>] (__lock_acquire+0x1928/0x1ce4) [<c0076218>] (__lock_acquire) from [<c0076de8>] (lock_acquire+0xb4/0x154) [<c0076de8>] (lock_acquire) from [<c0166b70>] (__kernfs_remove+0x254/0x310) [<c0166b70>] (__kernfs_remove) from [<c0167aa0>] (kernfs_remove_by_name_ns+0x4c/0x94) [<c0167aa0>] (kernfs_remove_by_name_ns) from [<c0169fb8>] (remove_files.isra.1+0x48/0x84) [<c0169fb8>] (remove_files.isra.1) from [<c016a2fc>] (sysfs_remove_group+0x58/0xac) [<c016a2fc>] (sysfs_remove_group) from [<c016a414>] (sysfs_remove_groups+0x34/0x44) [<c016a414>] (sysfs_remove_groups) from [<c02623b8>] (driver_remove_groups+0x1c/0x20) [<c02623b8>] (driver_remove_groups) from [<c0260e9c>] (bus_remove_driver+0x3c/0xe4) [<c0260e9c>] (bus_remove_driver) from [<c026235c>] (driver_unregister+0x38/0x58) [<c026235c>] (driver_unregister) from [<bf007fb4>] (usb_serial_bus_deregister+0x84/0x88 [usbserial]) [<bf007fb4>] (usb_serial_bus_deregister [usbserial]) from [<bf004db4>] (usb_serial_deregister+0x6c/0x78 [usbserial]) [<bf004db4>] (usb_serial_deregister [usbserial]) from [<bf005330>] (usb_serial_deregister_drivers+0x2c/0x4c [usbserial]) [<bf005330>] (usb_serial_deregister_drivers [usbserial]) from [<bf016618>] (usb_serial_module_exit+0x14/0x1c [sierra]) [<bf016618>] (usb_serial_module_exit [sierra]) from [<c009d6cc>] (SyS_delete_module+0x184/0x210) [<c009d6cc>] (SyS_delete_module) from [<c000f880>] (ret_fast_syscall+0x0/0x48) Signed-off-by: Johan Hovold <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

BugLink: http://bugs.launchpad.net/bugs/1333837 commit 10164c2 upstream. Fix driver new_id sysfs-attribute removal deadlock by making sure to not hold any locks that the attribute operations grab when removing the attribute. Specifically, usb_serial_deregister holds the table mutex when deregistering the driver, which includes removing the new_id attribute. This can lead to a deadlock as writing to new_id increments the attribute's active count before trying to grab the same mutex in usb_serial_probe. The deadlock can easily be triggered by inserting a sleep in usb_serial_deregister and writing the id of an unbound device to new_id during module unload. As the table mutex (in this case) is used to prevent subdriver unload during probe, it should be sufficient to only hold the lock while manipulating the usb-serial driver list during deregister. A racing probe will then either fail to find a matching subdriver or fail to get the corresponding module reference. Since v3.15-rc1 this also triggers the following lockdep warning: ====================================================== [ INFO: possible circular locking dependency detected ] 3.15.0-rc2 torvalds#123 Tainted: G W ------------------------------------------------------- modprobe/190 is trying to acquire lock: (s_active#4){++++.+}, at: [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 but task is already holding lock: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (table_lock){+.+.+.}: [<c0075f84>] __lock_acquire+0x1694/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c03af3cc>] _raw_spin_lock+0x4c/0x5c [<c02bbc24>] usb_store_new_id+0x14c/0x1ac [<bf007eb4>] new_id_store+0x68/0x70 [usbserial] [<c025f568>] drv_attr_store+0x30/0x3c [<c01690e0>] sysfs_kf_write+0x5c/0x60 [<c01682c0>] kernfs_fop_write+0xd4/0x194 [<c010881c>] vfs_write+0xbc/0x198 [<c0108e4c>] SyS_write+0x4c/0xa0 [<c000f880>] ret_fast_syscall+0x0/0x48 -> #0 (s_active#4){++++.+}: [<c03a7a28>] print_circular_bug+0x68/0x2f8 [<c0076218>] __lock_acquire+0x1928/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c0166b70>] __kernfs_remove+0x254/0x310 [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 [<c0169fb8>] remove_files.isra.1+0x48/0x84 [<c016a2fc>] sysfs_remove_group+0x58/0xac [<c016a414>] sysfs_remove_groups+0x34/0x44 [<c02623b8>] driver_remove_groups+0x1c/0x20 [<c0260e9c>] bus_remove_driver+0x3c/0xe4 [<c026235c>] driver_unregister+0x38/0x58 [<bf007fb4>] usb_serial_bus_deregister+0x84/0x88 [usbserial] [<bf004db4>] usb_serial_deregister+0x6c/0x78 [usbserial] [<bf005330>] usb_serial_deregister_drivers+0x2c/0x4c [usbserial] [<bf016618>] usb_serial_module_exit+0x14/0x1c [sierra] [<c009d6cc>] SyS_delete_module+0x184/0x210 [<c000f880>] ret_fast_syscall+0x0/0x48 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(table_lock); lock(s_active#4); lock(table_lock); lock(s_active#4); *** DEADLOCK *** 1 lock held by modprobe/190: #0: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] stack backtrace: CPU: 0 PID: 190 Comm: modprobe Tainted: G W 3.15.0-rc2 torvalds#123 [<c0015e10>] (unwind_backtrace) from [<c0013728>] (show_stack+0x20/0x24) [<c0013728>] (show_stack) from [<c03a9a54>] (dump_stack+0x24/0x28) [<c03a9a54>] (dump_stack) from [<c03a7cac>] (print_circular_bug+0x2ec/0x2f8) [<c03a7cac>] (print_circular_bug) from [<c0076218>] (__lock_acquire+0x1928/0x1ce4) [<c0076218>] (__lock_acquire) from [<c0076de8>] (lock_acquire+0xb4/0x154) [<c0076de8>] (lock_acquire) from [<c0166b70>] (__kernfs_remove+0x254/0x310) [<c0166b70>] (__kernfs_remove) from [<c0167aa0>] (kernfs_remove_by_name_ns+0x4c/0x94) [<c0167aa0>] (kernfs_remove_by_name_ns) from [<c0169fb8>] (remove_files.isra.1+0x48/0x84) [<c0169fb8>] (remove_files.isra.1) from [<c016a2fc>] (sysfs_remove_group+0x58/0xac) [<c016a2fc>] (sysfs_remove_group) from [<c016a414>] (sysfs_remove_groups+0x34/0x44) [<c016a414>] (sysfs_remove_groups) from [<c02623b8>] (driver_remove_groups+0x1c/0x20) [<c02623b8>] (driver_remove_groups) from [<c0260e9c>] (bus_remove_driver+0x3c/0xe4) [<c0260e9c>] (bus_remove_driver) from [<c026235c>] (driver_unregister+0x38/0x58) [<c026235c>] (driver_unregister) from [<bf007fb4>] (usb_serial_bus_deregister+0x84/0x88 [usbserial]) [<bf007fb4>] (usb_serial_bus_deregister [usbserial]) from [<bf004db4>] (usb_serial_deregister+0x6c/0x78 [usbserial]) [<bf004db4>] (usb_serial_deregister [usbserial]) from [<bf005330>] (usb_serial_deregister_drivers+0x2c/0x4c [usbserial]) [<bf005330>] (usb_serial_deregister_drivers [usbserial]) from [<bf016618>] (usb_serial_module_exit+0x14/0x1c [sierra]) [<bf016618>] (usb_serial_module_exit [sierra]) from [<c009d6cc>] (SyS_delete_module+0x184/0x210) [<c009d6cc>] (SyS_delete_module) from [<c000f880>] (ret_fast_syscall+0x0/0x48) Signed-off-by: Johan Hovold <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> Signed-off-by: Kamal Mostafa <[email protected]>

Since commit 0f04cf8 ("drm/exynos: fix wrong pipe calculation for crtc"), fimd_clear_channel() can be called when is_drm_iommu_supported() returns true. In this case, the kernel is going to be panicked because crtc is not set yet. [ 1.211156] [drm] Initialized drm 1.1.0 20060810 [ 1.216785] Unable to handle kernel NULL pointer dereference at virtual address 00000350 [ 1.223415] pgd = c0004000 [ 1.226086] [00000350] *pgd=00000000 [ 1.229649] Internal error: Oops: 5 [#1] PREEMPT SMP ARM [ 1.234940] Modules linked in: [ 1.237982] CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.0.0-rc1-00062-g7a7cc79-dirty #123 [ 1.246136] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 1.252214] task: ee8c8000 ti: ee8d0000 task.ti: ee8d0000 [ 1.257606] PC is at fimd_wait_for_vblank+0x8/0xc8 [ 1.262370] LR is at fimd_bind+0x138/0x1a8 [ 1.266450] pc : [<c02fb63c>] lr : [<c02fb834>] psr: 20000113 [ 1.266450] sp : ee8d1d28 ip : 00000000 fp : 00000000 [ 1.277906] r10: 00000001 r9 : c09d693c r8 : c0a2d6a8 [ 1.283114] r7 : 00000034 r6 : 00000001 r5 : ee0bb400 r4 : ee244c10 [ 1.289624] r3 : 00000000 r2 : 00000000 r1 : 00000001 r0 : 00000000 [ 1.296135] Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel [ 1.303426] Control: 10c5387d Table: 4000404a DAC: 00000015 [ 1.309154] Process swapper/0 (pid: 1, stack limit = 0xee8d0210) [ 1.315143] Stack: (0xee8d1d28 to 0xee8d2000) [ 1.319486] 1d20: 00000000 c0113d18 ee0bb400 ee0bb400 ee245c30 eebbe210 [ 1.327645] 1d40: ee008a40 ee244c10 ee0bb400 00000001 00000034 c02fb834 00000000 c030a858 [ 1.335804] 1d60: ee244a10 eeb60780 ee008a40 eeb60740 ee0bb400 c03030d0 00000000 00000000 [ 1.343963] 1d80: ee244a10 ee0bb400 00000000 eeb60740 eeb60810 00000000 00000000 c02f6ba4 [ 1.352123] 1da0: ee0bb400 00000000 00000000 c02e0500 ee244a00 c0a04a14 ee0bb400 c02e1de4 [ 1.360282] 1dc0: 00000000 c030a858 00000002 eeb60820 eeb60820 00000002 eeb60780 c03033d4 [ 1.368441] 1de0: c06e9cec 00000000 ee244a10 eeb60780 c0a056f8 c03035fc c0a04b24 c0a04b24 [ 1.376600] 1e00: ee244a10 00000001 c0a049d0 c02f6d34 c0ad462c eeba0790 00000000 ee244a10 [ 1.384759] 1e20: ffffffed c0a049d0 00000000 c03090b0 ee244a10 c0ad462c c0a2d840 c03077a0 [ 1.392919] 1e40: eeb5e880 c024b738 000008db ee244a10 c0a049d0 ee244a44 00000000 c09e71d8 [ 1.401078] 1e60: 000000c6 c0307a6c c0a049d0 00000000 c03079e0 c0305ea8 ee826e5c ee1dc7b4 [ 1.409237] 1e80: c0a049d0 eeb5e880 c0a058a8 c0306e2c c0896204 c0a049d0 c06e9d10 c0a049d0 [ 1.417396] 1ea0: c06e9d10 c0ad4600 00000000 c0308360 00000000 00000003 c06e9d10 c02f6e14 [ 1.425555] 1ec0: 00000000 c0896204 ffffffff 00000000 00000000 00000000 00000000 00000000 [ 1.433714] 1ee0: 00000000 00000000 c02f6d5c c02f6d5c 00000000 eeb5d740 c09e71d8 c0008a30 [ 1.441874] 1f00: ef7fca5e 00000000 00000000 00000066 00000000 ee8d1f28 c003ff1c c02514e8 [ 1.450033] 1f20: 60000113 ffffffff c093906c ef7fca5e 000000c6 c004018c 00000000 c093906c [ 1.458192] 1f40: c08a9690 c093840c 00000006 00000006 c09eb2ac c09c0d74 00000006 c09c0d54 [ 1.466351] 1f60: c0a3d680 c09745a0 c09d693c 000000c6 00000000 c0974db4 00000006 00000006 [ 1.474510] 1f80: c09745a0 ffffffff 00000000 c0692e00 00000000 00000000 00000000 00000000 [ 1.482669] 1fa0: 00000000 c0692e08 00000000 c000f040 00000000 00000000 00000000 00000000 [ 1.490828] 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 1.498988] 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000 ffffffff ffffffff [ 1.507159] [<c02fb63c>] (fimd_wait_for_vblank) from [<c02fb834>] (fimd_bind+0x138/0x1a8) [ 1.515313] [<c02fb834>] (fimd_bind) from [<c03030d0>] (component_bind_all+0xc4/0x20c) [ 1.523209] [<c03030d0>] (component_bind_all) from [<c02f6ba4>] (exynos_drm_load+0xa0/0x140) [ 1.531632] [<c02f6ba4>] (exynos_drm_load) from [<c02e0500>] (drm_dev_register+0xa0/0xf4) [ 1.539788] [<c02e0500>] (drm_dev_register) from [<c02e1de4>] (drm_platform_init+0x44/0xcc) [ 1.548121] [<c02e1de4>] (drm_platform_init) from [<c03033d4>] (try_to_bring_up_master.part.1+0xc8/0x104) [ 1.557668] [<c03033d4>] (try_to_bring_up_master.part.1) from [<c03035fc>] (component_master_add_with_match+0xd0/0x118) [ 1.568431] [<c03035fc>] (component_master_add_with_match) from [<c02f6d34>] (exynos_drm_platform_probe+0xf0/0x118) [ 1.578847] [<c02f6d34>] (exynos_drm_platform_probe) from [<c03090b0>] (platform_drv_probe+0x48/0x98) [ 1.588052] [<c03090b0>] (platform_drv_probe) from [<c03077a0>] (driver_probe_device+0x140/0x380) [ 1.596902] [<c03077a0>] (driver_probe_device) from [<c0307a6c>] (__driver_attach+0x8c/0x90) [ 1.605321] [<c0307a6c>] (__driver_attach) from [<c0305ea8>] (bus_for_each_dev+0x54/0x88) [ 1.613480] [<c0305ea8>] (bus_for_each_dev) from [<c0306e2c>] (bus_add_driver+0xec/0x200) [ 1.621640] [<c0306e2c>] (bus_add_driver) from [<c0308360>] (driver_register+0x78/0xf4) [ 1.629625] [<c0308360>] (driver_register) from [<c02f6e14>] (exynos_drm_init+0xb8/0x11c) [ 1.637785] [<c02f6e14>] (exynos_drm_init) from [<c0008a30>] (do_one_initcall+0xac/0x1ec) [ 1.645950] [<c0008a30>] (do_one_initcall) from [<c0974db4>] (kernel_init_freeable+0x194/0x268) [ 1.654626] [<c0974db4>] (kernel_init_freeable) from [<c0692e08>] (kernel_init+0x8/0xe4) [ 1.662699] [<c0692e08>] (kernel_init) from [<c000f040>] (ret_from_fork+0x14/0x34) [ 1.670246] Code: eaffffd5 c09df884 e92d40f0 e24dd01c (e5905350) [ 1.676408] ---[ end trace 804468492f306a6f ]--- [ 1.680948] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b [ 1.680948] [ 1.690035] CPU1: stopping [ 1.692727] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G D 4.0.0-rc1-00062-g7a7cc79-dirty #123 [ 1.702097] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 1.708192] [<c0016c84>] (unwind_backtrace) from [<c00129bc>] (show_stack+0x10/0x14) [ 1.715908] [<c00129bc>] (show_stack) from [<c0696f58>] (dump_stack+0x78/0xc8) [ 1.723108] [<c0696f58>] (dump_stack) from [<c0015020>] (handle_IPI+0x16c/0x2b4) [ 1.730485] [<c0015020>] (handle_IPI) from [<c00086bc>] (gic_handle_irq+0x64/0x6c) [ 1.738036] [<c00086bc>] (gic_handle_irq) from [<c00134c0>] (__irq_svc+0x40/0x74) [ 1.745498] Exception stack(0xee8fdf98 to 0xee8fdfe0) [ 1.750533] df80: 00000000 00000000 [ 1.758695] dfa0: ee8fdfe8 c0021780 c09df938 00000015 10c0387d c0a3d988 4000406a c09df8d4 [ 1.766853] dfc0: c0a27a74 c09df94 01000000 ee8fdfe0 c00101c0 c00101c4 60000113 ffffffff [ 1.775015] [<c00134c0>] (__irq_svc) from [<c00101c4>] (arch_cpu_idle+0x30/0x3c) [ 1.782397] [<c00101c4>] (arch_cpu_idle) from [<c005e804>] (cpu_startup_entry+0x180/0x324) [ 1.790639] [<c005e804>] (cpu_startup_entry) from [<40008764>] (0x40008764) [ 1.797579] CPU0: stopping [ 1.800272] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G D 4.0.0-rc1-00062-g7a7cc79-dirty #123 [ 1.809642] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 1.815730] [<c0016c84>] (unwind_backtrace) from [<c00129bc>] (show_stack+0x10/0x14) [ 1.823450] [<c00129bc>] (show_stack) from [<c0696f58>] (dump_stack+0x78/0xc8) [ 1.830653] [<c0696f58>] (dump_stack) from [<c0015020>] (handle_IPI+0x16c/0x2b4) [ 1.838030] [<c0015020>] (handle_IPI) from [<c00086bc>] (gic_handle_irq+0x64/0x6c) [ 1.845581] [<c00086bc>] (gic_handle_irq) from [<c00134c0>] (__irq_svc+0x40/0x74) [ 1.853043] Exception stack(0xc09ddf60 to 0xc09ddfa8) [ 1.858081] df60: 00000000 00000000 c09ddfb0 c0021780 c09df938 00000001 ffffffff c0a3d680 [ 1.866239] df80: c09c0dec c09df8d4 c0a27a74 c09df94 01000000 c09ddfa8 c00101c0 c00101c4 [ 1.874396] dfa0: 60000113 ffffffff [ 1.877872] [<c00134c0>] (__irq_svc) from [<c00101c4>] (arch_cpu_idle+0x30/0x3c) [ 1.885251] [<c00101c4>] (arch_cpu_idle) from [<c005e804>] (cpu_startup_entry+0x180/0x324) [ 1.893499] [<c005e804>] (cpu_startup_entry) from [<c0974bc8>] (start_kernel+0x324/0x37c) [ 1.901655] [<c0974bc8>] (start_kernel) from [<40008074>] (0x40008074) [ 1.908161] CPU3: stopping [ 1.910855] CPU: 3 PID: 0 Comm: swapper/3 Tainted: G D 4.0.0-rc1-00062-g7a7cc79-dirty #123 [ 1.920225] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 1.926313] [<c0016c84>] (unwind_backtrace) from [<c00129bc>] (show_stack+0x10/0x14) [ 1.934034] [<c00129bc>] (show_stack) from [<c0696f58>] (dump_stack+0x78/0xc8) [ 1.941237] [<c0696f58>] (dump_stack) from [<c0015020>] (handle_IPI+0x16c/0x2b4) [ 1.948613] [<c0015020>] (handle_IPI) from [<c00086bc>] (gic_handle_irq+0x64/0x6c) [ 1.956165] [<c00086bc>] (gic_handle_irq) from [<c00134c0>] (__irq_svc+0x40/0x74) [ 1.963626] Exception stack(0xee901f98 to 0xee901fe0) [ 1.968661] 1f80: 00000000 00000000 [ 1.976823] 1fa0: ee901fe8 c0021780 c09df938 00000015 10c0387d c0a3d988 4000406a c09df8d4 [ 1.984982] 1fc0: c0a27a74 c09df94 01000000 ee901fe0 c00101c0 c00101c4 60000113 ffffffff [ 1.993143] [<c00134c0>] (__irq_svc) from [<c00101c4>] (arch_cpu_idle+0x30/0x3c) [ 2.000522] [<c00101c4>] (arch_cpu_idle) from [<c005e804>] (cpu_startup_entry+0x180/0x324) [ 2.008765] [<c005e804>] (cpu_startup_entry) from [<40008764>] (0x40008764) [ 2.015710] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b Signed-off-by: Hyungwon Hwang <[email protected]> Signed-off-by: Inki Dae <[email protected]>

Since commit 0f04cf8 ("drm/exynos: fix wrong pipe calculation for crtc"), fimd_clear_channel() can be called when is_drm_iommu_supported() returns true. In this case, the kernel is going to be panicked because crtc is not set yet. [ 1.211156] [drm] Initialized drm 1.1.0 20060810 [ 1.216785] Unable to handle kernel NULL pointer dereference at virtual address 00000350 [ 1.223415] pgd = c0004000 [ 1.226086] [00000350] *pgd=00000000 [ 1.229649] Internal error: Oops: 5 [#1] PREEMPT SMP ARM [ 1.234940] Modules linked in: [ 1.237982] CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.0.0-rc1-00062-g7a7cc79-dirty torvalds#123 [ 1.246136] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 1.252214] task: ee8c8000 ti: ee8d0000 task.ti: ee8d0000 [ 1.257606] PC is at fimd_wait_for_vblank+0x8/0xc8 [ 1.262370] LR is at fimd_bind+0x138/0x1a8 [ 1.266450] pc : [<c02fb63c>] lr : [<c02fb834>] psr: 20000113 [ 1.266450] sp : ee8d1d28 ip : 00000000 fp : 00000000 [ 1.277906] r10: 00000001 r9 : c09d693c r8 : c0a2d6a8 [ 1.283114] r7 : 00000034 r6 : 00000001 r5 : ee0bb400 r4 : ee244c10 [ 1.289624] r3 : 00000000 r2 : 00000000 r1 : 00000001 r0 : 00000000 [ 1.296135] Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel [ 1.303426] Control: 10c5387d Table: 4000404a DAC: 00000015 [ 1.309154] Process swapper/0 (pid: 1, stack limit = 0xee8d0210) [ 1.315143] Stack: (0xee8d1d28 to 0xee8d2000) [ 1.319486] 1d20: 00000000 c0113d18 ee0bb400 ee0bb400 ee245c30 eebbe210 [ 1.327645] 1d40: ee008a40 ee244c10 ee0bb400 00000001 00000034 c02fb834 00000000 c030a858 [ 1.335804] 1d60: ee244a10 eeb60780 ee008a40 eeb60740 ee0bb400 c03030d0 00000000 00000000 [ 1.343963] 1d80: ee244a10 ee0bb400 00000000 eeb60740 eeb60810 00000000 00000000 c02f6ba4 [ 1.352123] 1da0: ee0bb400 00000000 00000000 c02e0500 ee244a00 c0a04a14 ee0bb400 c02e1de4 [ 1.360282] 1dc0: 00000000 c030a858 00000002 eeb60820 eeb60820 00000002 eeb60780 c03033d4 [ 1.368441] 1de0: c06e9cec 00000000 ee244a10 eeb60780 c0a056f8 c03035fc c0a04b24 c0a04b24 [ 1.376600] 1e00: ee244a10 00000001 c0a049d0 c02f6d34 c0ad462c eeba0790 00000000 ee244a10 [ 1.384759] 1e20: ffffffed c0a049d0 00000000 c03090b0 ee244a10 c0ad462c c0a2d840 c03077a0 [ 1.392919] 1e40: eeb5e880 c024b738 000008db ee244a10 c0a049d0 ee244a44 00000000 c09e71d8 [ 1.401078] 1e60: 000000c6 c0307a6c c0a049d0 00000000 c03079e0 c0305ea8 ee826e5c ee1dc7b4 [ 1.409237] 1e80: c0a049d0 eeb5e880 c0a058a8 c0306e2c c0896204 c0a049d0 c06e9d10 c0a049d0 [ 1.417396] 1ea0: c06e9d10 c0ad4600 00000000 c0308360 00000000 00000003 c06e9d10 c02f6e14 [ 1.425555] 1ec0: 00000000 c0896204 ffffffff 00000000 00000000 00000000 00000000 00000000 [ 1.433714] 1ee0: 00000000 00000000 c02f6d5c c02f6d5c 00000000 eeb5d740 c09e71d8 c0008a30 [ 1.441874] 1f00: ef7fca5e 00000000 00000000 00000066 00000000 ee8d1f28 c003ff1c c02514e8 [ 1.450033] 1f20: 60000113 ffffffff c093906c ef7fca5e 000000c6 c004018c 00000000 c093906c [ 1.458192] 1f40: c08a9690 c093840c 00000006 00000006 c09eb2ac c09c0d74 00000006 c09c0d54 [ 1.466351] 1f60: c0a3d680 c09745a0 c09d693c 000000c6 00000000 c0974db4 00000006 00000006 [ 1.474510] 1f80: c09745a0 ffffffff 00000000 c0692e00 00000000 00000000 00000000 00000000 [ 1.482669] 1fa0: 00000000 c0692e08 00000000 c000f040 00000000 00000000 00000000 00000000 [ 1.490828] 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 1.498988] 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000 ffffffff ffffffff [ 1.507159] [<c02fb63c>] (fimd_wait_for_vblank) from [<c02fb834>] (fimd_bind+0x138/0x1a8) [ 1.515313] [<c02fb834>] (fimd_bind) from [<c03030d0>] (component_bind_all+0xc4/0x20c) [ 1.523209] [<c03030d0>] (component_bind_all) from [<c02f6ba4>] (exynos_drm_load+0xa0/0x140) [ 1.531632] [<c02f6ba4>] (exynos_drm_load) from [<c02e0500>] (drm_dev_register+0xa0/0xf4) [ 1.539788] [<c02e0500>] (drm_dev_register) from [<c02e1de4>] (drm_platform_init+0x44/0xcc) [ 1.548121] [<c02e1de4>] (drm_platform_init) from [<c03033d4>] (try_to_bring_up_master.part.1+0xc8/0x104) [ 1.557668] [<c03033d4>] (try_to_bring_up_master.part.1) from [<c03035fc>] (component_master_add_with_match+0xd0/0x118) [ 1.568431] [<c03035fc>] (component_master_add_with_match) from [<c02f6d34>] (exynos_drm_platform_probe+0xf0/0x118) [ 1.578847] [<c02f6d34>] (exynos_drm_platform_probe) from [<c03090b0>] (platform_drv_probe+0x48/0x98) [ 1.588052] [<c03090b0>] (platform_drv_probe) from [<c03077a0>] (driver_probe_device+0x140/0x380) [ 1.596902] [<c03077a0>] (driver_probe_device) from [<c0307a6c>] (__driver_attach+0x8c/0x90) [ 1.605321] [<c0307a6c>] (__driver_attach) from [<c0305ea8>] (bus_for_each_dev+0x54/0x88) [ 1.613480] [<c0305ea8>] (bus_for_each_dev) from [<c0306e2c>] (bus_add_driver+0xec/0x200) [ 1.621640] [<c0306e2c>] (bus_add_driver) from [<c0308360>] (driver_register+0x78/0xf4) [ 1.629625] [<c0308360>] (driver_register) from [<c02f6e14>] (exynos_drm_init+0xb8/0x11c) [ 1.637785] [<c02f6e14>] (exynos_drm_init) from [<c0008a30>] (do_one_initcall+0xac/0x1ec) [ 1.645950] [<c0008a30>] (do_one_initcall) from [<c0974db4>] (kernel_init_freeable+0x194/0x268) [ 1.654626] [<c0974db4>] (kernel_init_freeable) from [<c0692e08>] (kernel_init+0x8/0xe4) [ 1.662699] [<c0692e08>] (kernel_init) from [<c000f040>] (ret_from_fork+0x14/0x34) [ 1.670246] Code: eaffffd5 c09df884 e92d40f0 e24dd01c (e5905350) [ 1.676408] ---[ end trace 804468492f306a6f ]--- [ 1.680948] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b [ 1.680948] [ 1.690035] CPU1: stopping [ 1.692727] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G D 4.0.0-rc1-00062-g7a7cc79-dirty torvalds#123 [ 1.702097] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 1.708192] [<c0016c84>] (unwind_backtrace) from [<c00129bc>] (show_stack+0x10/0x14) [ 1.715908] [<c00129bc>] (show_stack) from [<c0696f58>] (dump_stack+0x78/0xc8) [ 1.723108] [<c0696f58>] (dump_stack) from [<c0015020>] (handle_IPI+0x16c/0x2b4) [ 1.730485] [<c0015020>] (handle_IPI) from [<c00086bc>] (gic_handle_irq+0x64/0x6c) [ 1.738036] [<c00086bc>] (gic_handle_irq) from [<c00134c0>] (__irq_svc+0x40/0x74) [ 1.745498] Exception stack(0xee8fdf98 to 0xee8fdfe0) [ 1.750533] df80: 00000000 00000000 [ 1.758695] dfa0: ee8fdfe8 c0021780 c09df938 00000015 10c0387d c0a3d988 4000406a c09df8d4 [ 1.766853] dfc0: c0a27a74 c09df94 01000000 ee8fdfe0 c00101c0 c00101c4 60000113 ffffffff [ 1.775015] [<c00134c0>] (__irq_svc) from [<c00101c4>] (arch_cpu_idle+0x30/0x3c) [ 1.782397] [<c00101c4>] (arch_cpu_idle) from [<c005e804>] (cpu_startup_entry+0x180/0x324) [ 1.790639] [<c005e804>] (cpu_startup_entry) from [<40008764>] (0x40008764) [ 1.797579] CPU0: stopping [ 1.800272] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G D 4.0.0-rc1-00062-g7a7cc79-dirty torvalds#123 [ 1.809642] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 1.815730] [<c0016c84>] (unwind_backtrace) from [<c00129bc>] (show_stack+0x10/0x14) [ 1.823450] [<c00129bc>] (show_stack) from [<c0696f58>] (dump_stack+0x78/0xc8) [ 1.830653] [<c0696f58>] (dump_stack) from [<c0015020>] (handle_IPI+0x16c/0x2b4) [ 1.838030] [<c0015020>] (handle_IPI) from [<c00086bc>] (gic_handle_irq+0x64/0x6c) [ 1.845581] [<c00086bc>] (gic_handle_irq) from [<c00134c0>] (__irq_svc+0x40/0x74) [ 1.853043] Exception stack(0xc09ddf60 to 0xc09ddfa8) [ 1.858081] df60: 00000000 00000000 c09ddfb0 c0021780 c09df938 00000001 ffffffff c0a3d680 [ 1.866239] df80: c09c0dec c09df8d4 c0a27a74 c09df94 01000000 c09ddfa8 c00101c0 c00101c4 [ 1.874396] dfa0: 60000113 ffffffff [ 1.877872] [<c00134c0>] (__irq_svc) from [<c00101c4>] (arch_cpu_idle+0x30/0x3c) [ 1.885251] [<c00101c4>] (arch_cpu_idle) from [<c005e804>] (cpu_startup_entry+0x180/0x324) [ 1.893499] [<c005e804>] (cpu_startup_entry) from [<c0974bc8>] (start_kernel+0x324/0x37c) [ 1.901655] [<c0974bc8>] (start_kernel) from [<40008074>] (0x40008074) [ 1.908161] CPU3: stopping [ 1.910855] CPU: 3 PID: 0 Comm: swapper/3 Tainted: G D 4.0.0-rc1-00062-g7a7cc79-dirty torvalds#123 [ 1.920225] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 1.926313] [<c0016c84>] (unwind_backtrace) from [<c00129bc>] (show_stack+0x10/0x14) [ 1.934034] [<c00129bc>] (show_stack) from [<c0696f58>] (dump_stack+0x78/0xc8) [ 1.941237] [<c0696f58>] (dump_stack) from [<c0015020>] (handle_IPI+0x16c/0x2b4) [ 1.948613] [<c0015020>] (handle_IPI) from [<c00086bc>] (gic_handle_irq+0x64/0x6c) [ 1.956165] [<c00086bc>] (gic_handle_irq) from [<c00134c0>] (__irq_svc+0x40/0x74) [ 1.963626] Exception stack(0xee901f98 to 0xee901fe0) [ 1.968661] 1f80: 00000000 00000000 [ 1.976823] 1fa0: ee901fe8 c0021780 c09df938 00000015 10c0387d c0a3d988 4000406a c09df8d4 [ 1.984982] 1fc0: c0a27a74 c09df94 01000000 ee901fe0 c00101c0 c00101c4 60000113 ffffffff [ 1.993143] [<c00134c0>] (__irq_svc) from [<c00101c4>] (arch_cpu_idle+0x30/0x3c) [ 2.000522] [<c00101c4>] (arch_cpu_idle) from [<c005e804>] (cpu_startup_entry+0x180/0x324) [ 2.008765] [<c005e804>] (cpu_startup_entry) from [<40008764>] (0x40008764) [ 2.015710] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b Signed-off-by: Hyungwon Hwang <[email protected]> Signed-off-by: Inki Dae <[email protected]>

commit 10164c2 upstream. Fix driver new_id sysfs-attribute removal deadlock by making sure to not hold any locks that the attribute operations grab when removing the attribute. Specifically, usb_serial_deregister holds the table mutex when deregistering the driver, which includes removing the new_id attribute. This can lead to a deadlock as writing to new_id increments the attribute's active count before trying to grab the same mutex in usb_serial_probe. The deadlock can easily be triggered by inserting a sleep in usb_serial_deregister and writing the id of an unbound device to new_id during module unload. As the table mutex (in this case) is used to prevent subdriver unload during probe, it should be sufficient to only hold the lock while manipulating the usb-serial driver list during deregister. A racing probe will then either fail to find a matching subdriver or fail to get the corresponding module reference. Since v3.15-rc1 this also triggers the following lockdep warning: ====================================================== [ INFO: possible circular locking dependency detected ] 3.15.0-rc2 torvalds#123 Tainted: G W ------------------------------------------------------- modprobe/190 is trying to acquire lock: (s_active#4){++++.+}, at: [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 but task is already holding lock: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (table_lock){+.+.+.}: [<c0075f84>] __lock_acquire+0x1694/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c03af3cc>] _raw_spin_lock+0x4c/0x5c [<c02bbc24>] usb_store_new_id+0x14c/0x1ac [<bf007eb4>] new_id_store+0x68/0x70 [usbserial] [<c025f568>] drv_attr_store+0x30/0x3c [<c01690e0>] sysfs_kf_write+0x5c/0x60 [<c01682c0>] kernfs_fop_write+0xd4/0x194 [<c010881c>] vfs_write+0xbc/0x198 [<c0108e4c>] SyS_write+0x4c/0xa0 [<c000f880>] ret_fast_syscall+0x0/0x48 -> #0 (s_active#4){++++.+}: [<c03a7a28>] print_circular_bug+0x68/0x2f8 [<c0076218>] __lock_acquire+0x1928/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c0166b70>] __kernfs_remove+0x254/0x310 [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 [<c0169fb8>] remove_files.isra.1+0x48/0x84 [<c016a2fc>] sysfs_remove_group+0x58/0xac [<c016a414>] sysfs_remove_groups+0x34/0x44 [<c02623b8>] driver_remove_groups+0x1c/0x20 [<c0260e9c>] bus_remove_driver+0x3c/0xe4 [<c026235c>] driver_unregister+0x38/0x58 [<bf007fb4>] usb_serial_bus_deregister+0x84/0x88 [usbserial] [<bf004db4>] usb_serial_deregister+0x6c/0x78 [usbserial] [<bf005330>] usb_serial_deregister_drivers+0x2c/0x4c [usbserial] [<bf016618>] usb_serial_module_exit+0x14/0x1c [sierra] [<c009d6cc>] SyS_delete_module+0x184/0x210 [<c000f880>] ret_fast_syscall+0x0/0x48 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(table_lock); lock(s_active#4); lock(table_lock); lock(s_active#4); *** DEADLOCK *** 1 lock held by modprobe/190: #0: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] stack backtrace: CPU: 0 PID: 190 Comm: modprobe Tainted: G W 3.15.0-rc2 torvalds#123 [<c0015e10>] (unwind_backtrace) from [<c0013728>] (show_stack+0x20/0x24) [<c0013728>] (show_stack) from [<c03a9a54>] (dump_stack+0x24/0x28) [<c03a9a54>] (dump_stack) from [<c03a7cac>] (print_circular_bug+0x2ec/0x2f8) [<c03a7cac>] (print_circular_bug) from [<c0076218>] (__lock_acquire+0x1928/0x1ce4) [<c0076218>] (__lock_acquire) from [<c0076de8>] (lock_acquire+0xb4/0x154) [<c0076de8>] (lock_acquire) from [<c0166b70>] (__kernfs_remove+0x254/0x310) [<c0166b70>] (__kernfs_remove) from [<c0167aa0>] (kernfs_remove_by_name_ns+0x4c/0x94) [<c0167aa0>] (kernfs_remove_by_name_ns) from [<c0169fb8>] (remove_files.isra.1+0x48/0x84) [<c0169fb8>] (remove_files.isra.1) from [<c016a2fc>] (sysfs_remove_group+0x58/0xac) [<c016a2fc>] (sysfs_remove_group) from [<c016a414>] (sysfs_remove_groups+0x34/0x44) [<c016a414>] (sysfs_remove_groups) from [<c02623b8>] (driver_remove_groups+0x1c/0x20) [<c02623b8>] (driver_remove_groups) from [<c0260e9c>] (bus_remove_driver+0x3c/0xe4) [<c0260e9c>] (bus_remove_driver) from [<c026235c>] (driver_unregister+0x38/0x58) [<c026235c>] (driver_unregister) from [<bf007fb4>] (usb_serial_bus_deregister+0x84/0x88 [usbserial]) [<bf007fb4>] (usb_serial_bus_deregister [usbserial]) from [<bf004db4>] (usb_serial_deregister+0x6c/0x78 [usbserial]) [<bf004db4>] (usb_serial_deregister [usbserial]) from [<bf005330>] (usb_serial_deregister_drivers+0x2c/0x4c [usbserial]) [<bf005330>] (usb_serial_deregister_drivers [usbserial]) from [<bf016618>] (usb_serial_module_exit+0x14/0x1c [sierra]) [<bf016618>] (usb_serial_module_exit [sierra]) from [<c009d6cc>] (SyS_delete_module+0x184/0x210) [<c009d6cc>] (SyS_delete_module) from [<c000f880>] (ret_fast_syscall+0x0/0x48) Signed-off-by: Johan Hovold <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <[email protected]>

arm64: hi6220: add spi0 pinmux definition

GuC client object is always pinned during its life cycle. We cache the vmap of client object, which includes guc_process_desc, doorbell and work queue. By doing so, we can simplify the code where driver communicate with GuC. As a result, this patch removes the kmap_atomic in wq_check_space, where usleep_range could be called while kmap_atomic is held. This fixes issue below. [ 34.098798] BUG: scheduling while atomic: gem_close_race/1941/0x00000002 [ 34.098822] Modules linked in: hid_generic usbhid i915 asix usbnet libphy mii i2c_algo_bit drm_kms_helper cfbfillrect syscopyarea cfbimgblt sysfillrect sysimgblt fb_sys_fops cfbcopyarea drm coretemp i2c_hid hid video pinctrl_sunrisepoint pinctrl_intel acpi_pad nls_iso8859_1 e1000e ptp psmouse pps_core ahci libahci [ 34.098824] CPU: 0 PID: 1941 Comm: gem_close_race Tainted: G U 4.4.0-160121+ torvalds#123 [ 34.098824] Hardware name: Intel Corporation Skylake Client platform/Skylake AIO DDR3L RVP10, BIOS SKLSE2R1.R00.X100.B01.1509220551 09/22/2015 [ 34.098825] 0000000000013e40 ffff880166c27a78 ffffffff81280d02 ffff880172c13e40 [ 34.098826] ffff880166c27a88 ffffffff810c203a ffff880166c27ac8 ffffffff814ec808 [ 34.098827] ffff88016b7c6000 ffff880166c28000 00000000000f4240 0000000000000001 [ 34.098827] Call Trace: [ 34.098831] [<ffffffff81280d02>] dump_stack+0x4b/0x79 [ 34.098833] [<ffffffff810c203a>] __schedule_bug+0x41/0x4f [ 34.098834] [<ffffffff814ec808>] __schedule+0x5a8/0x690 [ 34.098835] [<ffffffff814ec927>] schedule+0x37/0x80 [ 34.098836] [<ffffffff814ef3fd>] schedule_hrtimeout_range_clock+0xad/0x130 [ 34.098837] [<ffffffff81090be0>] ? hrtimer_init+0x10/0x10 [ 34.098838] [<ffffffff814ef3f1>] ? schedule_hrtimeout_range_clock+0xa1/0x130 [ 34.098839] [<ffffffff814ef48e>] schedule_hrtimeout_range+0xe/0x10 [ 34.098840] [<ffffffff814eef9b>] usleep_range+0x3b/0x40 [ 34.098853] [<ffffffffa01ec109>] i915_guc_wq_check_space+0x119/0x210 [i915] [ 34.098861] [<ffffffffa01da47c>] intel_logical_ring_alloc_request_extras+0x5c/0x70 [i915] [ 34.098869] [<ffffffffa01cdbf1>] i915_gem_request_alloc+0x91/0x170 [i915] [ 34.098875] [<ffffffffa01c1c07>] i915_gem_do_execbuffer.isra.25+0xbc7/0x12a0 [i915] [ 34.098882] [<ffffffffa01cb785>] ? i915_gem_object_get_pages_gtt+0x225/0x3c0 [i915] [ 34.098889] [<ffffffffa01d1fb6>] ? i915_gem_pwrite_ioctl+0xd6/0x9f0 [i915] [ 34.098895] [<ffffffffa01c2e68>] i915_gem_execbuffer2+0xa8/0x250 [i915] [ 34.098900] [<ffffffffa00f65d8>] drm_ioctl+0x258/0x4f0 [drm] [ 34.098906] [<ffffffffa01c2dc0>] ? i915_gem_execbuffer+0x340/0x340 [i915] [ 34.098908] [<ffffffff8111590d>] do_vfs_ioctl+0x2cd/0x4a0 [ 34.098909] [<ffffffff8111eac2>] ? __fget+0x72/0xb0 [ 34.098910] [<ffffffff81115b1c>] SyS_ioctl+0x3c/0x70 [ 34.098911] [<ffffffff814effd7>] entry_SYSCALL_64_fastpath+0x12/0x6a [ 34.100208] ------------[ cut here ]------------ Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93847 Cc: Dave Gordon <[email protected]> Cc: Daniel Vetter <[email protected]> Cc: Tvrtko Ursulin <[email protected]> Signed-off-by: Alex Dai <[email protected]>

GuC client object is always pinned during its life cycle. We cache the vmap of client object, which includes guc_process_desc, doorbell and work queue. By doing so, we can simplify the code where driver communicate with GuC. As a result, this patch removes the kmap_atomic in wq_check_space, where usleep_range could be called while kmap_atomic is held. This fixes issue below. v2: Pass page actual numbers to i915_gem_object_vmap(). Also, check return value for error handling. (Tvrtko Ursulin) v1: vmap is done by i915_gem_object_vmap(). [ 34.098798] BUG: scheduling while atomic: gem_close_race/1941/0x00000002 [ 34.098822] Modules linked in: hid_generic usbhid i915 asix usbnet libphy mii i2c_algo_bit drm_kms_helper cfbfillrect syscopyarea cfbimgblt sysfillrect sysimgblt fb_sys_fops cfbcopyarea drm coretemp i2c_hid hid video pinctrl_sunrisepoint pinctrl_intel acpi_pad nls_iso8859_1 e1000e ptp psmouse pps_core ahci libahci [ 34.098824] CPU: 0 PID: 1941 Comm: gem_close_race Tainted: G U 4.4.0-160121+ torvalds#123 [ 34.098824] Hardware name: Intel Corporation Skylake Client platform/Skylake AIO DDR3L RVP10, BIOS SKLSE2R1.R00.X100.B01.1509220551 09/22/2015 [ 34.098825] 0000000000013e40 ffff880166c27a78 ffffffff81280d02 ffff880172c13e40 [ 34.098826] ffff880166c27a88 ffffffff810c203a ffff880166c27ac8 ffffffff814ec808 [ 34.098827] ffff88016b7c6000 ffff880166c28000 00000000000f4240 0000000000000001 [ 34.098827] Call Trace: [ 34.098831] [<ffffffff81280d02>] dump_stack+0x4b/0x79 [ 34.098833] [<ffffffff810c203a>] __schedule_bug+0x41/0x4f [ 34.098834] [<ffffffff814ec808>] __schedule+0x5a8/0x690 [ 34.098835] [<ffffffff814ec927>] schedule+0x37/0x80 [ 34.098836] [<ffffffff814ef3fd>] schedule_hrtimeout_range_clock+0xad/0x130 [ 34.098837] [<ffffffff81090be0>] ? hrtimer_init+0x10/0x10 [ 34.098838] [<ffffffff814ef3f1>] ? schedule_hrtimeout_range_clock+0xa1/0x130 [ 34.098839] [<ffffffff814ef48e>] schedule_hrtimeout_range+0xe/0x10 [ 34.098840] [<ffffffff814eef9b>] usleep_range+0x3b/0x40 [ 34.098853] [<ffffffffa01ec109>] i915_guc_wq_check_space+0x119/0x210 [i915] [ 34.098861] [<ffffffffa01da47c>] intel_logical_ring_alloc_request_extras+0x5c/0x70 [i915] [ 34.098869] [<ffffffffa01cdbf1>] i915_gem_request_alloc+0x91/0x170 [i915] [ 34.098875] [<ffffffffa01c1c07>] i915_gem_do_execbuffer.isra.25+0xbc7/0x12a0 [i915] [ 34.098882] [<ffffffffa01cb785>] ? i915_gem_object_get_pages_gtt+0x225/0x3c0 [i915] [ 34.098889] [<ffffffffa01d1fb6>] ? i915_gem_pwrite_ioctl+0xd6/0x9f0 [i915] [ 34.098895] [<ffffffffa01c2e68>] i915_gem_execbuffer2+0xa8/0x250 [i915] [ 34.098900] [<ffffffffa00f65d8>] drm_ioctl+0x258/0x4f0 [drm] [ 34.098906] [<ffffffffa01c2dc0>] ? i915_gem_execbuffer+0x340/0x340 [i915] [ 34.098908] [<ffffffff8111590d>] do_vfs_ioctl+0x2cd/0x4a0 [ 34.098909] [<ffffffff8111eac2>] ? __fget+0x72/0xb0 [ 34.098910] [<ffffffff81115b1c>] SyS_ioctl+0x3c/0x70 [ 34.098911] [<ffffffff814effd7>] entry_SYSCALL_64_fastpath+0x12/0x6a [ 34.100208] ------------[ cut here ]------------ Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93847 Cc: Dave Gordon <[email protected]> Cc: Daniel Vetter <[email protected]> Cc: Tvrtko Ursulin <[email protected]> Signed-off-by: Alex Dai <[email protected]>

Now that we keep GuC shared objects mapped into kernel space for their entire lifetime, we can simplify the code for accessing the doorbells and work queue, which were previously calling kmap_atomic() on *each* request submission. This patch fixes the BUG shown below, where the thread could sleep while holding the kmap_atomic mapping. [ 34.098798] BUG: scheduling while atomic: gem_close_race/1941/0x00000002 [ 34.098822] Modules linked in: hid_generic usbhid i915 asix usbnet libphy mii i2c_algo_bit drm_kms_helper cfbfillrect syscopyarea cfbimgblt sysfillrect sysimgblt fb_sys_fops cfbcopyarea drm coretemp i2c_hid hid video pinctrl_sunrisepoint pinctrl_intel acpi_pad nls_iso8859_1 e1000e ptp psmouse pps_core ahci libahci [ 34.098824] CPU: 0 PID: 1941 Comm: gem_close_race Tainted: G U 4.4.0-160121+ torvalds#123 [ 34.098824] Hardware name: Intel Corporation Skylake Client platform/Skylake AIO DDR3L RVP10, BIOS SKLSE2R1.R00.X100.B01.1509220551 09/22/2015 [ 34.098825] 0000000000013e40 ffff880166c27a78 ffffffff81280d02 ffff880172c13e40 [ 34.098826] ffff880166c27a88 ffffffff810c203a ffff880166c27ac8 ffffffff814ec808 [ 34.098827] ffff88016b7c6000 ffff880166c28000 00000000000f4240 0000000000000001 [ 34.098827] Call Trace: [ 34.098831] [<ffffffff81280d02>] dump_stack+0x4b/0x79 [ 34.098833] [<ffffffff810c203a>] __schedule_bug+0x41/0x4f [ 34.098834] [<ffffffff814ec808>] __schedule+0x5a8/0x690 [ 34.098835] [<ffffffff814ec927>] schedule+0x37/0x80 [ 34.098836] [<ffffffff814ef3fd>] schedule_hrtimeout_range_clock+0xad/0x130 [ 34.098837] [<ffffffff81090be0>] ? hrtimer_init+0x10/0x10 [ 34.098838] [<ffffffff814ef3f1>] ? schedule_hrtimeout_range_clock+0xa1/0x130 [ 34.098839] [<ffffffff814ef48e>] schedule_hrtimeout_range+0xe/0x10 [ 34.098840] [<ffffffff814eef9b>] usleep_range+0x3b/0x40 [ 34.098853] [<ffffffffa01ec109>] i915_guc_wq_check_space+0x119/0x210 [i915] [ 34.098861] [<ffffffffa01da47c>] intel_logical_ring_alloc_request_extras+0x5c/0x70 [i915] [ 34.098869] [<ffffffffa01cdbf1>] i915_gem_request_alloc+0x91/0x170 [i915] [ 34.098875] [<ffffffffa01c1c07>] i915_gem_do_execbuffer.isra.25+0xbc7/0x12a0 [i915] [ 34.098882] [<ffffffffa01cb785>] ? i915_gem_object_get_pages_gtt+0x225/0x3c0 [i915] [ 34.098889] [<ffffffffa01d1fb6>] ? i915_gem_pwrite_ioctl+0xd6/0x9f0 [i915] [ 34.098895] [<ffffffffa01c2e68>] i915_gem_execbuffer2+0xa8/0x250 [i915] [ 34.098900] [<ffffffffa00f65d8>] drm_ioctl+0x258/0x4f0 [drm] [ 34.098906] [<ffffffffa01c2dc0>] ? i915_gem_execbuffer+0x340/0x340 [i915] [ 34.098908] [<ffffffff8111590d>] do_vfs_ioctl+0x2cd/0x4a0 [ 34.098909] [<ffffffff8111eac2>] ? __fget+0x72/0xb0 [ 34.098910] [<ffffffff81115b1c>] SyS_ioctl+0x3c/0x70 [ 34.098911] [<ffffffff814effd7>] entry_SYSCALL_64_fastpath+0x12/0x6a [ 34.100208] ------------[ cut here ]------------ Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93847 Cc: <[email protected]> Cc: <[email protected]> Signed-off-by: Alex Dai <[email protected]> Signed-off-by: Dave Gordon <[email protected]>

Don't use kmap_atomic() for doorbell & process descriptor access. This patch fixes the BUG shown below, where the thread could sleep while holding a kmap_atomic mapping. In order not to need to call kmap_atomic() in this code path, we now set up a permanent kernel mapping of the shared doorbell and process-descriptor page, and use that in all doorbell and process-descriptor related code. BUG: scheduling while atomic: gem_close_race/1941/0x00000002 Modules linked in: hid_generic usbhid i915 asix usbnet libphy mii i2c_algo_bit drm_kms_helper cfbfillrect syscopyarea cfbimgblt sysfillrect sysimgblt fb_sys_fops cfbcopyarea drm coretemp i2c_hid hid video pinctrl_sunrisepoint pinctrl_intel acpi_pad nls_iso8859_1 e1000e ptp psmouse pps_core ahci libahci CPU: 0 PID: 1941 Comm: gem_close_race Tainted: G U 4.4.0-160121+ torvalds#123 Hardware name: Intel Corporation Skylake Client platform/Skylake AIO DDR3L RVP10, BIOS SKLSE2R1.R00.X100.B01.1509220551 09/22/2015 0000000000013e40 ffff880166c27a78 ffffffff81280d02 ffff880172c13e40 ffff880166c27a88 ffffffff810c203a ffff880166c27ac8 ffffffff814ec808 ffff88016b7c6000 ffff880166c28000 00000000000f4240 0000000000000001 Call Trace: [<ffffffff81280d02>] dump_stack+0x4b/0x79 [<ffffffff810c203a>] __schedule_bug+0x41/0x4f [<ffffffff814ec808>] __schedule+0x5a8/0x690 [<ffffffff814ec927>] schedule+0x37/0x80 [<ffffffff814ef3fd>] schedule_hrtimeout_range_clock+0xad/0x130 [<ffffffff81090be0>] ? hrtimer_init+0x10/0x10 [<ffffffff814ef3f1>] ? schedule_hrtimeout_range_clock+0xa1/0x130 [<ffffffff814ef48e>] schedule_hrtimeout_range+0xe/0x10 [<ffffffff814eef9b>] usleep_range+0x3b/0x40 [<ffffffffa01ec109>] i915_guc_wq_check_space+0x119/0x210 [i915] [<ffffffffa01da47c>] intel_logical_ring_alloc_request_extras+0x5c/0x70 [i915] [<ffffffffa01cdbf1>] i915_gem_request_alloc+0x91/0x170 [i915] [<ffffffffa01c1c07>] i915_gem_do_execbuffer.isra.25+0xbc7/0x12a0 [i915] [<ffffffffa01cb785>] ? i915_gem_object_get_pages_gtt+0x225/0x3c0 [i915] [<ffffffffa01d1fb6>] ? i915_gem_pwrite_ioctl+0xd6/0x9f0 [i915] [<ffffffffa01c2e68>] i915_gem_execbuffer2+0xa8/0x250 [i915] [<ffffffffa00f65d8>] drm_ioctl+0x258/0x4f0 [drm] [<ffffffffa01c2dc0>] ? i915_gem_execbuffer+0x340/0x340 [i915] [<ffffffff8111590d>] do_vfs_ioctl+0x2cd/0x4a0 [<ffffffff8111eac2>] ? __fget+0x72/0xb0 [<ffffffff81115b1c>] SyS_ioctl+0x3c/0x70 [<ffffffff814effd7>] entry_SYSCALL_64_fastpath+0x12/0x6a ------------[ cut here ]------------ Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93847 Original-version-by: Alex Dai <[email protected]> Signed-off-by: Dave Gordon <[email protected]> Cc: Tvtrko Ursulin <[email protected]>

Don't use kmap_atomic() for doorbell & process descriptor access. This patch fixes the BUG shown below, where the thread could sleep while holding a kmap_atomic mapping. In order not to need to call kmap_atomic() in this code path, we now set up a permanent kernel mapping of the shared doorbell and process-descriptor page, and use that in all doorbell and process-descriptor related code. BUG: scheduling while atomic: gem_close_race/1941/0x00000002 Modules linked in: hid_generic usbhid i915 asix usbnet libphy mii i2c_algo_bit drm_kms_helper cfbfillrect syscopyarea cfbimgblt sysfillrect sysimgblt fb_sys_fops cfbcopyarea drm coretemp i2c_hid hid video pinctrl_sunrisepoint pinctrl_intel acpi_pad nls_iso8859_1 e1000e ptp psmouse pps_core ahci libahci CPU: 0 PID: 1941 Comm: gem_close_race Tainted: G U 4.4.0-160121+ torvalds#123 Hardware name: Intel Corporation Skylake Client platform/Skylake AIO DDR3L RVP10, BIOS SKLSE2R1.R00.X100.B01.1509220551 09/22/2015 0000000000013e40 ffff880166c27a78 ffffffff81280d02 ffff880172c13e40 ffff880166c27a88 ffffffff810c203a ffff880166c27ac8 ffffffff814ec808 ffff88016b7c6000 ffff880166c28000 00000000000f4240 0000000000000001 Call Trace: [<ffffffff81280d02>] dump_stack+0x4b/0x79 [<ffffffff810c203a>] __schedule_bug+0x41/0x4f [<ffffffff814ec808>] __schedule+0x5a8/0x690 [<ffffffff814ec927>] schedule+0x37/0x80 [<ffffffff814ef3fd>] schedule_hrtimeout_range_clock+0xad/0x130 [<ffffffff81090be0>] ? hrtimer_init+0x10/0x10 [<ffffffff814ef3f1>] ? schedule_hrtimeout_range_clock+0xa1/0x130 [<ffffffff814ef48e>] schedule_hrtimeout_range+0xe/0x10 [<ffffffff814eef9b>] usleep_range+0x3b/0x40 [<ffffffffa01ec109>] i915_guc_wq_check_space+0x119/0x210 [i915] [<ffffffffa01da47c>] intel_logical_ring_alloc_request_extras+0x5c/0x70 [i915] [<ffffffffa01cdbf1>] i915_gem_request_alloc+0x91/0x170 [i915] [<ffffffffa01c1c07>] i915_gem_do_execbuffer.isra.25+0xbc7/0x12a0 [i915] [<ffffffffa01cb785>] ? i915_gem_object_get_pages_gtt+0x225/0x3c0 [i915] [<ffffffffa01d1fb6>] ? i915_gem_pwrite_ioctl+0xd6/0x9f0 [i915] [<ffffffffa01c2e68>] i915_gem_execbuffer2+0xa8/0x250 [i915] [<ffffffffa00f65d8>] drm_ioctl+0x258/0x4f0 [drm] [<ffffffffa01c2dc0>] ? i915_gem_execbuffer+0x340/0x340 [i915] [<ffffffff8111590d>] do_vfs_ioctl+0x2cd/0x4a0 [<ffffffff8111eac2>] ? __fget+0x72/0xb0 [<ffffffff81115b1c>] SyS_ioctl+0x3c/0x70 [<ffffffff814effd7>] entry_SYSCALL_64_fastpath+0x12/0x6a ------------[ cut here ]------------ v4: Only tear down doorbell & kunmap() client object if we actually succeeded in allocating a client object (Tvrtko Ursulin) Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93847 Original-version-by: Alex Dai <[email protected]> Signed-off-by: Dave Gordon <[email protected]> Cc: Tvtrko Ursulin <[email protected]>

Don't use kmap_atomic() for doorbell & process descriptor access. This patch fixes the BUG shown below, where the thread could sleep while holding a kmap_atomic mapping. In order not to need to call kmap_atomic() in this code path, we now set up a permanent kernel mapping of the shared doorbell and process-descriptor page, and use that in all doorbell and process-descriptor related code. BUG: scheduling while atomic: gem_close_race/1941/0x00000002 Modules linked in: hid_generic usbhid i915 asix usbnet libphy mii i2c_algo_bit drm_kms_helper cfbfillrect syscopyarea cfbimgblt sysfillrect sysimgblt fb_sys_fops cfbcopyarea drm coretemp i2c_hid hid video pinctrl_sunrisepoint pinctrl_intel acpi_pad nls_iso8859_1 e1000e ptp psmouse pps_core ahci libahci CPU: 0 PID: 1941 Comm: gem_close_race Tainted: G U 4.4.0-160121+ torvalds#123 Hardware name: Intel Corporation Skylake Client platform/Skylake AIO DDR3L RVP10, BIOS SKLSE2R1.R00.X100.B01.1509220551 09/22/2015 0000000000013e40 ffff880166c27a78 ffffffff81280d02 ffff880172c13e40 ffff880166c27a88 ffffffff810c203a ffff880166c27ac8 ffffffff814ec808 ffff88016b7c6000 ffff880166c28000 00000000000f4240 0000000000000001 Call Trace: [<ffffffff81280d02>] dump_stack+0x4b/0x79 [<ffffffff810c203a>] __schedule_bug+0x41/0x4f [<ffffffff814ec808>] __schedule+0x5a8/0x690 [<ffffffff814ec927>] schedule+0x37/0x80 [<ffffffff814ef3fd>] schedule_hrtimeout_range_clock+0xad/0x130 [<ffffffff81090be0>] ? hrtimer_init+0x10/0x10 [<ffffffff814ef3f1>] ? schedule_hrtimeout_range_clock+0xa1/0x130 [<ffffffff814ef48e>] schedule_hrtimeout_range+0xe/0x10 [<ffffffff814eef9b>] usleep_range+0x3b/0x40 [<ffffffffa01ec109>] i915_guc_wq_check_space+0x119/0x210 [i915] [<ffffffffa01da47c>] intel_logical_ring_alloc_request_extras+0x5c/0x70 [i915] [<ffffffffa01cdbf1>] i915_gem_request_alloc+0x91/0x170 [i915] [<ffffffffa01c1c07>] i915_gem_do_execbuffer.isra.25+0xbc7/0x12a0 [i915] [<ffffffffa01cb785>] ? i915_gem_object_get_pages_gtt+0x225/0x3c0 [i915] [<ffffffffa01d1fb6>] ? i915_gem_pwrite_ioctl+0xd6/0x9f0 [i915] [<ffffffffa01c2e68>] i915_gem_execbuffer2+0xa8/0x250 [i915] [<ffffffffa00f65d8>] drm_ioctl+0x258/0x4f0 [drm] [<ffffffffa01c2dc0>] ? i915_gem_execbuffer+0x340/0x340 [i915] [<ffffffff8111590d>] do_vfs_ioctl+0x2cd/0x4a0 [<ffffffff8111eac2>] ? __fget+0x72/0xb0 [<ffffffff81115b1c>] SyS_ioctl+0x3c/0x70 [<ffffffff814effd7>] entry_SYSCALL_64_fastpath+0x12/0x6a ------------[ cut here ]------------ v4: Only tear down doorbell & kunmap() client object if we actually succeeded in allocating a client object (Tvrtko Ursulin) Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93847 Original-version-by: Alex Dai <[email protected]> Signed-off-by: Dave Gordon <[email protected]> Cc: Tvtrko Ursulin <[email protected]> Reviewed-by: Tvrtko Ursulin <[email protected]> Signed-off-by: Tvrtko Ursulin <[email protected]>

commit 10164c2 upstream. Fix driver new_id sysfs-attribute removal deadlock by making sure to not hold any locks that the attribute operations grab when removing the attribute. Specifically, usb_serial_deregister holds the table mutex when deregistering the driver, which includes removing the new_id attribute. This can lead to a deadlock as writing to new_id increments the attribute's active count before trying to grab the same mutex in usb_serial_probe. The deadlock can easily be triggered by inserting a sleep in usb_serial_deregister and writing the id of an unbound device to new_id during module unload. As the table mutex (in this case) is used to prevent subdriver unload during probe, it should be sufficient to only hold the lock while manipulating the usb-serial driver list during deregister. A racing probe will then either fail to find a matching subdriver or fail to get the corresponding module reference. Since v3.15-rc1 this also triggers the following lockdep warning: ====================================================== [ INFO: possible circular locking dependency detected ] 3.15.0-rc2 torvalds#123 Tainted: G W ------------------------------------------------------- modprobe/190 is trying to acquire lock: (s_active#4){++++.+}, at: [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 but task is already holding lock: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (table_lock){+.+.+.}: [<c0075f84>] __lock_acquire+0x1694/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c03af3cc>] _raw_spin_lock+0x4c/0x5c [<c02bbc24>] usb_store_new_id+0x14c/0x1ac [<bf007eb4>] new_id_store+0x68/0x70 [usbserial] [<c025f568>] drv_attr_store+0x30/0x3c [<c01690e0>] sysfs_kf_write+0x5c/0x60 [<c01682c0>] kernfs_fop_write+0xd4/0x194 [<c010881c>] vfs_write+0xbc/0x198 [<c0108e4c>] SyS_write+0x4c/0xa0 [<c000f880>] ret_fast_syscall+0x0/0x48 -> #0 (s_active#4){++++.+}: [<c03a7a28>] print_circular_bug+0x68/0x2f8 [<c0076218>] __lock_acquire+0x1928/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c0166b70>] __kernfs_remove+0x254/0x310 [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 [<c0169fb8>] remove_files.isra.1+0x48/0x84 [<c016a2fc>] sysfs_remove_group+0x58/0xac [<c016a414>] sysfs_remove_groups+0x34/0x44 [<c02623b8>] driver_remove_groups+0x1c/0x20 [<c0260e9c>] bus_remove_driver+0x3c/0xe4 [<c026235c>] driver_unregister+0x38/0x58 [<bf007fb4>] usb_serial_bus_deregister+0x84/0x88 [usbserial] [<bf004db4>] usb_serial_deregister+0x6c/0x78 [usbserial] [<bf005330>] usb_serial_deregister_drivers+0x2c/0x4c [usbserial] [<bf016618>] usb_serial_module_exit+0x14/0x1c [sierra] [<c009d6cc>] SyS_delete_module+0x184/0x210 [<c000f880>] ret_fast_syscall+0x0/0x48 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(table_lock); lock(s_active#4); lock(table_lock); lock(s_active#4); *** DEADLOCK *** 1 lock held by modprobe/190: #0: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] stack backtrace: CPU: 0 PID: 190 Comm: modprobe Tainted: G W 3.15.0-rc2 torvalds#123 [<c0015e10>] (unwind_backtrace) from [<c0013728>] (show_stack+0x20/0x24) [<c0013728>] (show_stack) from [<c03a9a54>] (dump_stack+0x24/0x28) [<c03a9a54>] (dump_stack) from [<c03a7cac>] (print_circular_bug+0x2ec/0x2f8) [<c03a7cac>] (print_circular_bug) from [<c0076218>] (__lock_acquire+0x1928/0x1ce4) [<c0076218>] (__lock_acquire) from [<c0076de8>] (lock_acquire+0xb4/0x154) [<c0076de8>] (lock_acquire) from [<c0166b70>] (__kernfs_remove+0x254/0x310) [<c0166b70>] (__kernfs_remove) from [<c0167aa0>] (kernfs_remove_by_name_ns+0x4c/0x94) [<c0167aa0>] (kernfs_remove_by_name_ns) from [<c0169fb8>] (remove_files.isra.1+0x48/0x84) [<c0169fb8>] (remove_files.isra.1) from [<c016a2fc>] (sysfs_remove_group+0x58/0xac) [<c016a2fc>] (sysfs_remove_group) from [<c016a414>] (sysfs_remove_groups+0x34/0x44) [<c016a414>] (sysfs_remove_groups) from [<c02623b8>] (driver_remove_groups+0x1c/0x20) [<c02623b8>] (driver_remove_groups) from [<c0260e9c>] (bus_remove_driver+0x3c/0xe4) [<c0260e9c>] (bus_remove_driver) from [<c026235c>] (driver_unregister+0x38/0x58) [<c026235c>] (driver_unregister) from [<bf007fb4>] (usb_serial_bus_deregister+0x84/0x88 [usbserial]) [<bf007fb4>] (usb_serial_bus_deregister [usbserial]) from [<bf004db4>] (usb_serial_deregister+0x6c/0x78 [usbserial]) [<bf004db4>] (usb_serial_deregister [usbserial]) from [<bf005330>] (usb_serial_deregister_drivers+0x2c/0x4c [usbserial]) [<bf005330>] (usb_serial_deregister_drivers [usbserial]) from [<bf016618>] (usb_serial_module_exit+0x14/0x1c [sierra]) [<bf016618>] (usb_serial_module_exit [sierra]) from [<c009d6cc>] (SyS_delete_module+0x184/0x210) [<c009d6cc>] (SyS_delete_module) from [<c000f880>] (ret_fast_syscall+0x0/0x48) Signed-off-by: Johan Hovold <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

commit 10164c2 upstream. Fix driver new_id sysfs-attribute removal deadlock by making sure to not hold any locks that the attribute operations grab when removing the attribute. Specifically, usb_serial_deregister holds the table mutex when deregistering the driver, which includes removing the new_id attribute. This can lead to a deadlock as writing to new_id increments the attribute's active count before trying to grab the same mutex in usb_serial_probe. The deadlock can easily be triggered by inserting a sleep in usb_serial_deregister and writing the id of an unbound device to new_id during module unload. As the table mutex (in this case) is used to prevent subdriver unload during probe, it should be sufficient to only hold the lock while manipulating the usb-serial driver list during deregister. A racing probe will then either fail to find a matching subdriver or fail to get the corresponding module reference. Since v3.15-rc1 this also triggers the following lockdep warning: ====================================================== [ INFO: possible circular locking dependency detected ] 3.15.0-rc2 torvalds#123 Tainted: G W ------------------------------------------------------- modprobe/190 is trying to acquire lock: (s_active#4){++++.+}, at: [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 but task is already holding lock: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (table_lock){+.+.+.}: [<c0075f84>] __lock_acquire+0x1694/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c03af3cc>] _raw_spin_lock+0x4c/0x5c [<c02bbc24>] usb_store_new_id+0x14c/0x1ac [<bf007eb4>] new_id_store+0x68/0x70 [usbserial] [<c025f568>] drv_attr_store+0x30/0x3c [<c01690e0>] sysfs_kf_write+0x5c/0x60 [<c01682c0>] kernfs_fop_write+0xd4/0x194 [<c010881c>] vfs_write+0xbc/0x198 [<c0108e4c>] SyS_write+0x4c/0xa0 [<c000f880>] ret_fast_syscall+0x0/0x48 -> #0 (s_active#4){++++.+}: [<c03a7a28>] print_circular_bug+0x68/0x2f8 [<c0076218>] __lock_acquire+0x1928/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c0166b70>] __kernfs_remove+0x254/0x310 [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 [<c0169fb8>] remove_files.isra.1+0x48/0x84 [<c016a2fc>] sysfs_remove_group+0x58/0xac [<c016a414>] sysfs_remove_groups+0x34/0x44 [<c02623b8>] driver_remove_groups+0x1c/0x20 [<c0260e9c>] bus_remove_driver+0x3c/0xe4 [<c026235c>] driver_unregister+0x38/0x58 [<bf007fb4>] usb_serial_bus_deregister+0x84/0x88 [usbserial] [<bf004db4>] usb_serial_deregister+0x6c/0x78 [usbserial] [<bf005330>] usb_serial_deregister_drivers+0x2c/0x4c [usbserial] [<bf016618>] usb_serial_module_exit+0x14/0x1c [sierra] [<c009d6cc>] SyS_delete_module+0x184/0x210 [<c000f880>] ret_fast_syscall+0x0/0x48 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(table_lock); lock(s_active#4); lock(table_lock); lock(s_active#4); *** DEADLOCK *** 1 lock held by modprobe/190: #0: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] stack backtrace: CPU: 0 PID: 190 Comm: modprobe Tainted: G W 3.15.0-rc2 torvalds#123 [<c0015e10>] (unwind_backtrace) from [<c0013728>] (show_stack+0x20/0x24) [<c0013728>] (show_stack) from [<c03a9a54>] (dump_stack+0x24/0x28) [<c03a9a54>] (dump_stack) from [<c03a7cac>] (print_circular_bug+0x2ec/0x2f8) [<c03a7cac>] (print_circular_bug) from [<c0076218>] (__lock_acquire+0x1928/0x1ce4) [<c0076218>] (__lock_acquire) from [<c0076de8>] (lock_acquire+0xb4/0x154) [<c0076de8>] (lock_acquire) from [<c0166b70>] (__kernfs_remove+0x254/0x310) [<c0166b70>] (__kernfs_remove) from [<c0167aa0>] (kernfs_remove_by_name_ns+0x4c/0x94) [<c0167aa0>] (kernfs_remove_by_name_ns) from [<c0169fb8>] (remove_files.isra.1+0x48/0x84) [<c0169fb8>] (remove_files.isra.1) from [<c016a2fc>] (sysfs_remove_group+0x58/0xac) [<c016a2fc>] (sysfs_remove_group) from [<c016a414>] (sysfs_remove_groups+0x34/0x44) [<c016a414>] (sysfs_remove_groups) from [<c02623b8>] (driver_remove_groups+0x1c/0x20) [<c02623b8>] (driver_remove_groups) from [<c0260e9c>] (bus_remove_driver+0x3c/0xe4) [<c0260e9c>] (bus_remove_driver) from [<c026235c>] (driver_unregister+0x38/0x58) [<c026235c>] (driver_unregister) from [<bf007fb4>] (usb_serial_bus_deregister+0x84/0x88 [usbserial]) [<bf007fb4>] (usb_serial_bus_deregister [usbserial]) from [<bf004db4>] (usb_serial_deregister+0x6c/0x78 [usbserial]) [<bf004db4>] (usb_serial_deregister [usbserial]) from [<bf005330>] (usb_serial_deregister_drivers+0x2c/0x4c [usbserial]) [<bf005330>] (usb_serial_deregister_drivers [usbserial]) from [<bf016618>] (usb_serial_module_exit+0x14/0x1c [sierra]) [<bf016618>] (usb_serial_module_exit [sierra]) from [<c009d6cc>] (SyS_delete_module+0x184/0x210) [<c009d6cc>] (SyS_delete_module) from [<c000f880>] (ret_fast_syscall+0x0/0x48) Signed-off-by: Johan Hovold <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

commit 10164c2 upstream. Fix driver new_id sysfs-attribute removal deadlock by making sure to not hold any locks that the attribute operations grab when removing the attribute. Specifically, usb_serial_deregister holds the table mutex when deregistering the driver, which includes removing the new_id attribute. This can lead to a deadlock as writing to new_id increments the attribute's active count before trying to grab the same mutex in usb_serial_probe. The deadlock can easily be triggered by inserting a sleep in usb_serial_deregister and writing the id of an unbound device to new_id during module unload. As the table mutex (in this case) is used to prevent subdriver unload during probe, it should be sufficient to only hold the lock while manipulating the usb-serial driver list during deregister. A racing probe will then either fail to find a matching subdriver or fail to get the corresponding module reference. Since v3.15-rc1 this also triggers the following lockdep warning: ====================================================== [ INFO: possible circular locking dependency detected ] 3.15.0-rc2 torvalds#123 Tainted: G W ------------------------------------------------------- modprobe/190 is trying to acquire lock: (s_active#4){++++.+}, at: [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 but task is already holding lock: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (table_lock){+.+.+.}: [<c0075f84>] __lock_acquire+0x1694/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c03af3cc>] _raw_spin_lock+0x4c/0x5c [<c02bbc24>] usb_store_new_id+0x14c/0x1ac [<bf007eb4>] new_id_store+0x68/0x70 [usbserial] [<c025f568>] drv_attr_store+0x30/0x3c [<c01690e0>] sysfs_kf_write+0x5c/0x60 [<c01682c0>] kernfs_fop_write+0xd4/0x194 [<c010881c>] vfs_write+0xbc/0x198 [<c0108e4c>] SyS_write+0x4c/0xa0 [<c000f880>] ret_fast_syscall+0x0/0x48 -> #0 (s_active#4){++++.+}: [<c03a7a28>] print_circular_bug+0x68/0x2f8 [<c0076218>] __lock_acquire+0x1928/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c0166b70>] __kernfs_remove+0x254/0x310 [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 [<c0169fb8>] remove_files.isra.1+0x48/0x84 [<c016a2fc>] sysfs_remove_group+0x58/0xac [<c016a414>] sysfs_remove_groups+0x34/0x44 [<c02623b8>] driver_remove_groups+0x1c/0x20 [<c0260e9c>] bus_remove_driver+0x3c/0xe4 [<c026235c>] driver_unregister+0x38/0x58 [<bf007fb4>] usb_serial_bus_deregister+0x84/0x88 [usbserial] [<bf004db4>] usb_serial_deregister+0x6c/0x78 [usbserial] [<bf005330>] usb_serial_deregister_drivers+0x2c/0x4c [usbserial] [<bf016618>] usb_serial_module_exit+0x14/0x1c [sierra] [<c009d6cc>] SyS_delete_module+0x184/0x210 [<c000f880>] ret_fast_syscall+0x0/0x48 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(table_lock); lock(s_active#4); lock(table_lock); lock(s_active#4); *** DEADLOCK *** 1 lock held by modprobe/190: #0: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] stack backtrace: CPU: 0 PID: 190 Comm: modprobe Tainted: G W 3.15.0-rc2 torvalds#123 [<c0015e10>] (unwind_backtrace) from [<c0013728>] (show_stack+0x20/0x24) [<c0013728>] (show_stack) from [<c03a9a54>] (dump_stack+0x24/0x28) [<c03a9a54>] (dump_stack) from [<c03a7cac>] (print_circular_bug+0x2ec/0x2f8) [<c03a7cac>] (print_circular_bug) from [<c0076218>] (__lock_acquire+0x1928/0x1ce4) [<c0076218>] (__lock_acquire) from [<c0076de8>] (lock_acquire+0xb4/0x154) [<c0076de8>] (lock_acquire) from [<c0166b70>] (__kernfs_remove+0x254/0x310) [<c0166b70>] (__kernfs_remove) from [<c0167aa0>] (kernfs_remove_by_name_ns+0x4c/0x94) [<c0167aa0>] (kernfs_remove_by_name_ns) from [<c0169fb8>] (remove_files.isra.1+0x48/0x84) [<c0169fb8>] (remove_files.isra.1) from [<c016a2fc>] (sysfs_remove_group+0x58/0xac) [<c016a2fc>] (sysfs_remove_group) from [<c016a414>] (sysfs_remove_groups+0x34/0x44) [<c016a414>] (sysfs_remove_groups) from [<c02623b8>] (driver_remove_groups+0x1c/0x20) [<c02623b8>] (driver_remove_groups) from [<c0260e9c>] (bus_remove_driver+0x3c/0xe4) [<c0260e9c>] (bus_remove_driver) from [<c026235c>] (driver_unregister+0x38/0x58) [<c026235c>] (driver_unregister) from [<bf007fb4>] (usb_serial_bus_deregister+0x84/0x88 [usbserial]) [<bf007fb4>] (usb_serial_bus_deregister [usbserial]) from [<bf004db4>] (usb_serial_deregister+0x6c/0x78 [usbserial]) [<bf004db4>] (usb_serial_deregister [usbserial]) from [<bf005330>] (usb_serial_deregister_drivers+0x2c/0x4c [usbserial]) [<bf005330>] (usb_serial_deregister_drivers [usbserial]) from [<bf016618>] (usb_serial_module_exit+0x14/0x1c [sierra]) [<bf016618>] (usb_serial_module_exit [sierra]) from [<c009d6cc>] (SyS_delete_module+0x184/0x210) [<c009d6cc>] (SyS_delete_module) from [<c000f880>] (ret_fast_syscall+0x0/0x48) Signed-off-by: Johan Hovold <[email protected]> Signed-off-by: Jiri Slaby <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

commit 10164c2 upstream. Fix driver new_id sysfs-attribute removal deadlock by making sure to not hold any locks that the attribute operations grab when removing the attribute. Specifically, usb_serial_deregister holds the table mutex when deregistering the driver, which includes removing the new_id attribute. This can lead to a deadlock as writing to new_id increments the attribute's active count before trying to grab the same mutex in usb_serial_probe. The deadlock can easily be triggered by inserting a sleep in usb_serial_deregister and writing the id of an unbound device to new_id during module unload. As the table mutex (in this case) is used to prevent subdriver unload during probe, it should be sufficient to only hold the lock while manipulating the usb-serial driver list during deregister. A racing probe will then either fail to find a matching subdriver or fail to get the corresponding module reference. Since v3.15-rc1 this also triggers the following lockdep warning: ====================================================== [ INFO: possible circular locking dependency detected ] 3.15.0-rc2 torvalds#123 Tainted: G W ------------------------------------------------------- modprobe/190 is trying to acquire lock: (s_active#4){++++.+}, at: [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 but task is already holding lock: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (table_lock){+.+.+.}: [<c0075f84>] __lock_acquire+0x1694/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c03af3cc>] _raw_spin_lock+0x4c/0x5c [<c02bbc24>] usb_store_new_id+0x14c/0x1ac [<bf007eb4>] new_id_store+0x68/0x70 [usbserial] [<c025f568>] drv_attr_store+0x30/0x3c [<c01690e0>] sysfs_kf_write+0x5c/0x60 [<c01682c0>] kernfs_fop_write+0xd4/0x194 [<c010881c>] vfs_write+0xbc/0x198 [<c0108e4c>] SyS_write+0x4c/0xa0 [<c000f880>] ret_fast_syscall+0x0/0x48 -> #0 (s_active#4){++++.+}: [<c03a7a28>] print_circular_bug+0x68/0x2f8 [<c0076218>] __lock_acquire+0x1928/0x1ce4 [<c0076de8>] lock_acquire+0xb4/0x154 [<c0166b70>] __kernfs_remove+0x254/0x310 [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94 [<c0169fb8>] remove_files.isra.1+0x48/0x84 [<c016a2fc>] sysfs_remove_group+0x58/0xac [<c016a414>] sysfs_remove_groups+0x34/0x44 [<c02623b8>] driver_remove_groups+0x1c/0x20 [<c0260e9c>] bus_remove_driver+0x3c/0xe4 [<c026235c>] driver_unregister+0x38/0x58 [<bf007fb4>] usb_serial_bus_deregister+0x84/0x88 [usbserial] [<bf004db4>] usb_serial_deregister+0x6c/0x78 [usbserial] [<bf005330>] usb_serial_deregister_drivers+0x2c/0x4c [usbserial] [<bf016618>] usb_serial_module_exit+0x14/0x1c [sierra] [<c009d6cc>] SyS_delete_module+0x184/0x210 [<c000f880>] ret_fast_syscall+0x0/0x48 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(table_lock); lock(s_active#4); lock(table_lock); lock(s_active#4); *** DEADLOCK *** 1 lock held by modprobe/190: #0: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial] stack backtrace: CPU: 0 PID: 190 Comm: modprobe Tainted: G W 3.15.0-rc2 torvalds#123 [<c0015e10>] (unwind_backtrace) from [<c0013728>] (show_stack+0x20/0x24) [<c0013728>] (show_stack) from [<c03a9a54>] (dump_stack+0x24/0x28) [<c03a9a54>] (dump_stack) from [<c03a7cac>] (print_circular_bug+0x2ec/0x2f8) [<c03a7cac>] (print_circular_bug) from [<c0076218>] (__lock_acquire+0x1928/0x1ce4) [<c0076218>] (__lock_acquire) from [<c0076de8>] (lock_acquire+0xb4/0x154) [<c0076de8>] (lock_acquire) from [<c0166b70>] (__kernfs_remove+0x254/0x310) [<c0166b70>] (__kernfs_remove) from [<c0167aa0>] (kernfs_remove_by_name_ns+0x4c/0x94) [<c0167aa0>] (kernfs_remove_by_name_ns) from [<c0169fb8>] (remove_files.isra.1+0x48/0x84) [<c0169fb8>] (remove_files.isra.1) from [<c016a2fc>] (sysfs_remove_group+0x58/0xac) [<c016a2fc>] (sysfs_remove_group) from [<c016a414>] (sysfs_remove_groups+0x34/0x44) [<c016a414>] (sysfs_remove_groups) from [<c02623b8>] (driver_remove_groups+0x1c/0x20) [<c02623b8>] (driver_remove_groups) from [<c0260e9c>] (bus_remove_driver+0x3c/0xe4) [<c0260e9c>] (bus_remove_driver) from [<c026235c>] (driver_unregister+0x38/0x58) [<c026235c>] (driver_unregister) from [<bf007fb4>] (usb_serial_bus_deregister+0x84/0x88 [usbserial]) [<bf007fb4>] (usb_serial_bus_deregister [usbserial]) from [<bf004db4>] (usb_serial_deregister+0x6c/0x78 [usbserial]) [<bf004db4>] (usb_serial_deregister [usbserial]) from [<bf005330>] (usb_serial_deregister_drivers+0x2c/0x4c [usbserial]) [<bf005330>] (usb_serial_deregister_drivers [usbserial]) from [<bf016618>] (usb_serial_module_exit+0x14/0x1c [sierra]) [<bf016618>] (usb_serial_module_exit [sierra]) from [<c009d6cc>] (SyS_delete_module+0x184/0x210) [<c009d6cc>] (SyS_delete_module) from [<c000f880>] (ret_fast_syscall+0x0/0x48) Signed-off-by: Johan Hovold <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

mem_cgroup_css_alloc() was returning NULL on failure while cgroup core expected it to return an ERR_PTR value leading to the following NULL deref after a css allocation failure. Fix it by return ERR_PTR(-ENOMEM) instead. I'll also update cgroup core so that it can handle NULL returns. mkdir: page allocation failure: order:6, mode:0x240c0c0(GFP_KERNEL|__GFP_COMP|__GFP_ZERO) CPU: 0 PID: 8738 Comm: mkdir Not tainted 4.7.0-rc3+ torvalds#123 ... Call Trace: [<ffffffff81321937>] dump_stack+0x68/0xa1 [<ffffffff811522f6>] warn_alloc_failed+0xd6/0x130 [<ffffffff81152816>] __alloc_pages_nodemask+0x4c6/0xf20 [<ffffffff8119df86>] alloc_pages_current+0x66/0xe0 [<ffffffff81153564>] alloc_kmem_pages+0x14/0x80 [<ffffffff811705ca>] kmalloc_order_trace+0x2a/0x1a0 [<ffffffff811a7a61>] __kmalloc+0x291/0x310 [<ffffffff811718dc>] memcg_update_all_caches+0x6c/0x130 [<ffffffff818d0290>] mem_cgroup_css_alloc+0x590/0x610 [<ffffffff810f4c7b>] cgroup_apply_control_enable+0x18b/0x370 [<ffffffff810f8afe>] cgroup_mkdir+0x1de/0x2e0 [<ffffffff8123cf35>] kernfs_iop_mkdir+0x55/0x80 [<ffffffff811c6599>] vfs_mkdir+0xb9/0x150 [<ffffffff811cc666>] SyS_mkdir+0x66/0xd0 [<ffffffff81002df3>] do_syscall_64+0x53/0x120 [<ffffffff818d719a>] entry_SYSCALL64_slow_path+0x25/0x25 ... BUG: unable to handle kernel NULL pointer dereference at 00000000000000d0 IP: [<ffffffff810f2ca7>] init_and_link_css+0x37/0x220 PGD 34b1e067 PUD 3a109067 PMD 0 Oops: 0002 [#1] SMP Modules linked in: CPU: 0 PID: 8738 Comm: mkdir Not tainted 4.7.0-rc3+ torvalds#123 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.2-20160422_131301-anatol 04/01/2014 task: ffff88007cbc5200 ti: ffff8800666d4000 task.ti: ffff8800666d4000 RIP: 0010:[<ffffffff810f2ca7>] [<ffffffff810f2ca7>] init_and_link_css+0x37/0x220 RSP: 0018:ffff8800666d7d90 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffffffff810f2499 RSI: 0000000000000000 RDI: 0000000000000008 RBP: ffff8800666d7db8 R08: 0000000000000003 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88005a5fb400 R13: ffffffff81f0f8a0 R14: ffff88005a5fb400 R15: 0000000000000010 FS: 00007fc944689700(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3aed0d2b80 CR3: 000000003a1e8000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffffffff81f0f8a0 ffffffff81f0f8a0 ffff88005a5fb400 0000000000000000 ffff88005a5fb400 ffff8800666d7e18 ffffffff810f4c9c ffff88005a5fb400 ffffffff82d23470 ffff88007cbc57f0 ffff88007cbc5200 ffff88007d013000 Call Trace: [<ffffffff810f4c9c>] cgroup_apply_control_enable+0x1ac/0x370 [<ffffffff810f8afe>] cgroup_mkdir+0x1de/0x2e0 [<ffffffff8123cf35>] kernfs_iop_mkdir+0x55/0x80 [<ffffffff811c6599>] vfs_mkdir+0xb9/0x150 [<ffffffff811cc666>] SyS_mkdir+0x66/0xd0 [<ffffffff81002df3>] do_syscall_64+0x53/0x120 [<ffffffff818d719a>] entry_SYSCALL64_slow_path+0x25/0x25 Code: 89 f5 48 89 fb 49 89 d4 48 83 ec 08 8b 05 72 3b d8 00 85 c0 0f 85 60 01 00 00 4c 89 e7 e8 72 f7 ff ff 48 8d 7b 08 48 89 d9 31 c0 <48> c7 83 d0 00 00 00 00 00 00 00 48 83 e7 f8 48 29 f9 81 c1 d8 RIP [<ffffffff810f2ca7>] init_and_link_css+0x37/0x220 RSP <ffff8800666d7d90> CR2: 00000000000000d0 ---[ end trace a2d8836ae1e852d1 ]--- Signed-off-by: Tejun Heo <[email protected]> Reported-by: Johannes Weiner <[email protected]> Cc: [email protected]

mem_cgroup_css_alloc() was returning NULL on failure while cgroup core expected it to return an ERR_PTR value leading to the following NULL deref after a css allocation failure. Fix it by return ERR_PTR(-ENOMEM) instead. I'll also update cgroup core so that it can handle NULL returns. mkdir: page allocation failure: order:6, mode:0x240c0c0(GFP_KERNEL|__GFP_COMP|__GFP_ZERO) CPU: 0 PID: 8738 Comm: mkdir Not tainted 4.7.0-rc3+ torvalds#123 ... Call Trace: [<ffffffff81321937>] dump_stack+0x68/0xa1 [<ffffffff811522f6>] warn_alloc_failed+0xd6/0x130 [<ffffffff81152816>] __alloc_pages_nodemask+0x4c6/0xf20 [<ffffffff8119df86>] alloc_pages_current+0x66/0xe0 [<ffffffff81153564>] alloc_kmem_pages+0x14/0x80 [<ffffffff811705ca>] kmalloc_order_trace+0x2a/0x1a0 [<ffffffff811a7a61>] __kmalloc+0x291/0x310 [<ffffffff811718dc>] memcg_update_all_caches+0x6c/0x130 [<ffffffff818d0290>] mem_cgroup_css_alloc+0x590/0x610 [<ffffffff810f4c7b>] cgroup_apply_control_enable+0x18b/0x370 [<ffffffff810f8afe>] cgroup_mkdir+0x1de/0x2e0 [<ffffffff8123cf35>] kernfs_iop_mkdir+0x55/0x80 [<ffffffff811c6599>] vfs_mkdir+0xb9/0x150 [<ffffffff811cc666>] SyS_mkdir+0x66/0xd0 [<ffffffff81002df3>] do_syscall_64+0x53/0x120 [<ffffffff818d719a>] entry_SYSCALL64_slow_path+0x25/0x25 ... BUG: unable to handle kernel NULL pointer dereference at 00000000000000d0 IP: [<ffffffff810f2ca7>] init_and_link_css+0x37/0x220 PGD 34b1e067 PUD 3a109067 PMD 0 Oops: 0002 [#1] SMP Modules linked in: CPU: 0 PID: 8738 Comm: mkdir Not tainted 4.7.0-rc3+ torvalds#123 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.2-20160422_131301-anatol 04/01/2014 task: ffff88007cbc5200 ti: ffff8800666d4000 task.ti: ffff8800666d4000 RIP: 0010:[<ffffffff810f2ca7>] [<ffffffff810f2ca7>] init_and_link_css+0x37/0x220 RSP: 0018:ffff8800666d7d90 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffffffff810f2499 RSI: 0000000000000000 RDI: 0000000000000008 RBP: ffff8800666d7db8 R08: 0000000000000003 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88005a5fb400 R13: ffffffff81f0f8a0 R14: ffff88005a5fb400 R15: 0000000000000010 FS: 00007fc944689700(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3aed0d2b80 CR3: 000000003a1e8000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffffffff81f0f8a0 ffffffff81f0f8a0 ffff88005a5fb400 0000000000000000 ffff88005a5fb400 ffff8800666d7e18 ffffffff810f4c9c ffff88005a5fb400 ffffffff82d23470 ffff88007cbc57f0 ffff88007cbc5200 ffff88007d013000 Call Trace: [<ffffffff810f4c9c>] cgroup_apply_control_enable+0x1ac/0x370 [<ffffffff810f8afe>] cgroup_mkdir+0x1de/0x2e0 [<ffffffff8123cf35>] kernfs_iop_mkdir+0x55/0x80 [<ffffffff811c6599>] vfs_mkdir+0xb9/0x150 [<ffffffff811cc666>] SyS_mkdir+0x66/0xd0 [<ffffffff81002df3>] do_syscall_64+0x53/0x120 [<ffffffff818d719a>] entry_SYSCALL64_slow_path+0x25/0x25 Code: 89 f5 48 89 fb 49 89 d4 48 83 ec 08 8b 05 72 3b d8 00 85 c0 0f 85 60 01 00 00 4c 89 e7 e8 72 f7 ff ff 48 8d 7b 08 48 89 d9 31 c0 <48> c7 83 d0 00 00 00 00 00 00 00 48 83 e7 f8 48 29 f9 81 c1 d8 RIP [<ffffffff810f2ca7>] init_and_link_css+0x37/0x220 RSP <ffff8800666d7d90> CR2: 00000000000000d0 ---[ end trace a2d8836ae1e852d1 ]--- Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Tejun Heo <[email protected]> Reported-by: Johannes Weiner <[email protected]> Acked-by: Johannes Weiner <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]>

mem_cgroup_css_alloc() was returning NULL on failure while cgroup core expected it to return an ERR_PTR value leading to the following NULL deref after a css allocation failure. Fix it by return ERR_PTR(-ENOMEM) instead. I'll also update cgroup core so that it can handle NULL returns. mkdir: page allocation failure: order:6, mode:0x240c0c0(GFP_KERNEL|__GFP_COMP|__GFP_ZERO) CPU: 0 PID: 8738 Comm: mkdir Not tainted 4.7.0-rc3+ #123 ... Call Trace: dump_stack+0x68/0xa1 warn_alloc_failed+0xd6/0x130 __alloc_pages_nodemask+0x4c6/0xf20 alloc_pages_current+0x66/0xe0 alloc_kmem_pages+0x14/0x80 kmalloc_order_trace+0x2a/0x1a0 __kmalloc+0x291/0x310 memcg_update_all_caches+0x6c/0x130 mem_cgroup_css_alloc+0x590/0x610 cgroup_apply_control_enable+0x18b/0x370 cgroup_mkdir+0x1de/0x2e0 kernfs_iop_mkdir+0x55/0x80 vfs_mkdir+0xb9/0x150 SyS_mkdir+0x66/0xd0 do_syscall_64+0x53/0x120 entry_SYSCALL64_slow_path+0x25/0x25 ... BUG: unable to handle kernel NULL pointer dereference at 00000000000000d0 IP: init_and_link_css+0x37/0x220 PGD 34b1e067 PUD 3a109067 PMD 0 Oops: 0002 [#1] SMP Modules linked in: CPU: 0 PID: 8738 Comm: mkdir Not tainted 4.7.0-rc3+ #123 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.2-20160422_131301-anatol 04/01/2014 task: ffff88007cbc5200 ti: ffff8800666d4000 task.ti: ffff8800666d4000 RIP: 0010:[<ffffffff810f2ca7>] [<ffffffff810f2ca7>] init_and_link_css+0x37/0x220 RSP: 0018:ffff8800666d7d90 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffffffff810f2499 RSI: 0000000000000000 RDI: 0000000000000008 RBP: ffff8800666d7db8 R08: 0000000000000003 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88005a5fb400 R13: ffffffff81f0f8a0 R14: ffff88005a5fb400 R15: 0000000000000010 FS: 00007fc944689700(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3aed0d2b80 CR3: 000000003a1e8000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: cgroup_apply_control_enable+0x1ac/0x370 cgroup_mkdir+0x1de/0x2e0 kernfs_iop_mkdir+0x55/0x80 vfs_mkdir+0xb9/0x150 SyS_mkdir+0x66/0xd0 do_syscall_64+0x53/0x120 entry_SYSCALL64_slow_path+0x25/0x25 Code: 89 f5 48 89 fb 49 89 d4 48 83 ec 08 8b 05 72 3b d8 00 85 c0 0f 85 60 01 00 00 4c 89 e7 e8 72 f7 ff ff 48 8d 7b 08 48 89 d9 31 c0 <48> c7 83 d0 00 00 00 00 00 00 00 48 83 e7 f8 48 29 f9 81 c1 d8 RIP init_and_link_css+0x37/0x220 RSP <ffff8800666d7d90> CR2: 00000000000000d0 ---[ end trace a2d8836ae1e852d1 ]--- Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Tejun Heo <[email protected]> Reported-by: Johannes Weiner <[email protected]> Reviewed-by: Vladimir Davydov <[email protected]> Acked-by: Johannes Weiner <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>

commit ea3a964 upstream. mem_cgroup_css_alloc() was returning NULL on failure while cgroup core expected it to return an ERR_PTR value leading to the following NULL deref after a css allocation failure. Fix it by return ERR_PTR(-ENOMEM) instead. I'll also update cgroup core so that it can handle NULL returns. mkdir: page allocation failure: order:6, mode:0x240c0c0(GFP_KERNEL|__GFP_COMP|__GFP_ZERO) CPU: 0 PID: 8738 Comm: mkdir Not tainted 4.7.0-rc3+ #123 ... Call Trace: dump_stack+0x68/0xa1 warn_alloc_failed+0xd6/0x130 __alloc_pages_nodemask+0x4c6/0xf20 alloc_pages_current+0x66/0xe0 alloc_kmem_pages+0x14/0x80 kmalloc_order_trace+0x2a/0x1a0 __kmalloc+0x291/0x310 memcg_update_all_caches+0x6c/0x130 mem_cgroup_css_alloc+0x590/0x610 cgroup_apply_control_enable+0x18b/0x370 cgroup_mkdir+0x1de/0x2e0 kernfs_iop_mkdir+0x55/0x80 vfs_mkdir+0xb9/0x150 SyS_mkdir+0x66/0xd0 do_syscall_64+0x53/0x120 entry_SYSCALL64_slow_path+0x25/0x25 ... BUG: unable to handle kernel NULL pointer dereference at 00000000000000d0 IP: init_and_link_css+0x37/0x220 PGD 34b1e067 PUD 3a109067 PMD 0 Oops: 0002 [#1] SMP Modules linked in: CPU: 0 PID: 8738 Comm: mkdir Not tainted 4.7.0-rc3+ #123 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.2-20160422_131301-anatol 04/01/2014 task: ffff88007cbc5200 ti: ffff8800666d4000 task.ti: ffff8800666d4000 RIP: 0010:[<ffffffff810f2ca7>] [<ffffffff810f2ca7>] init_and_link_css+0x37/0x220 RSP: 0018:ffff8800666d7d90 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffffffff810f2499 RSI: 0000000000000000 RDI: 0000000000000008 RBP: ffff8800666d7db8 R08: 0000000000000003 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88005a5fb400 R13: ffffffff81f0f8a0 R14: ffff88005a5fb400 R15: 0000000000000010 FS: 00007fc944689700(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3aed0d2b80 CR3: 000000003a1e8000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: cgroup_apply_control_enable+0x1ac/0x370 cgroup_mkdir+0x1de/0x2e0 kernfs_iop_mkdir+0x55/0x80 vfs_mkdir+0xb9/0x150 SyS_mkdir+0x66/0xd0 do_syscall_64+0x53/0x120 entry_SYSCALL64_slow_path+0x25/0x25 Code: 89 f5 48 89 fb 49 89 d4 48 83 ec 08 8b 05 72 3b d8 00 85 c0 0f 85 60 01 00 00 4c 89 e7 e8 72 f7 ff ff 48 8d 7b 08 48 89 d9 31 c0 <48> c7 83 d0 00 00 00 00 00 00 00 48 83 e7 f8 48 29 f9 81 c1 d8 RIP init_and_link_css+0x37/0x220 RSP <ffff8800666d7d90> CR2: 00000000000000d0 ---[ end trace a2d8836ae1e852d1 ]--- Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Tejun Heo <[email protected]> Reported-by: Johannes Weiner <[email protected]> Reviewed-by: Vladimir Davydov <[email protected]> Acked-by: Johannes Weiner <[email protected]> Acked-by: Michal Hocko <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

lkl: fix wakeup_cpu trashing the heap of host memory allocator.

When slub_debug=O is set. It is possible to clear debug flags for an "unmergeable" slab cache in kmem_cache_open(). It makes the "unmergeable" cache became "mergeable" in sysfs_slab_add(). These caches will generate their "unique IDs" by create_unique_id(), but it is possible to create identical unique IDs. In my experiment, sgpool-128, names_cache, biovec-256 generate the same ID ":Ft-0004096" and the kernel reports "sysfs: cannot create duplicate filename '/kernel/slab/:Ft-0004096'". To repeat my experiment, set disable_higher_order_debug=1, CONFIG_SLUB_DEBUG_ON=y in kernel-4.14. Fix this issue by setting unmergeable=1 if slub_debug=O and the the default slub_debug contains any no-merge flags. call path: kmem_cache_create() __kmem_cache_alias() -> we set SLAB_NEVER_MERGE flags here create_cache() __kmem_cache_create() kmem_cache_open() -> clear DEBUG_METADATA_FLAGS sysfs_slab_add() -> the slab cache is mergeable now [ 0.674272] sysfs: cannot create duplicate filename '/kernel/slab/:Ft-0004096' [ 0.674473] ------------[ cut here ]------------ [ 0.674653] WARNING: CPU: 0 PID: 1 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x60/0x7c [ 0.674847] Modules linked in: [ 0.674969] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 4.14.0-rc7ajb-00131-gd4c2e9f-dirty torvalds#123 [ 0.675211] Hardware name: linux,dummy-virt (DT) [ 0.675342] task: ffffffc07d4e0080 task.stack: ffffff8008008000 [ 0.675505] PC is at sysfs_warn_dup+0x60/0x7c [ 0.675633] LR is at sysfs_warn_dup+0x60/0x7c [ 0.675759] pc : [<ffffff8008235808>] lr : [<ffffff8008235808>] pstate: 60000145 [ 0.675948] sp : ffffff800800bb40 [ 0.676048] x29: ffffff800800bb40 x28: 0000000000000040 [ 0.676209] x27: ffffffc07c52a380 x26: 0000000000000000 [ 0.676369] x25: ffffff8008af4ad0 x24: ffffff8008af4000 [ 0.676528] x23: ffffffc07c532580 x22: ffffffc07cf04598 [ 0.676695] x21: ffffffc07cf26578 x20: ffffffc07c533700 [ 0.676857] x19: ffffffc07ce67000 x18: 0000000000000002 [ 0.677017] x17: 0000000000007ffe x16: 0000000000000007 [ 0.677176] x15: 0000000000000001 x14: 0000000000007fff [ 0.677335] x13: 0000000000000394 x12: 0000000000000000 [ 0.677492] x11: 00000000000001ab x10: 0000000000000007 [ 0.677651] x9 : 00000000000001ac x8 : ffffff800835d114 [ 0.677809] x7 : 656b2f2720656d61 x6 : 0000000000000017 [ 0.677967] x5 : ffffffc07ffdb9a8 x4 : 0000000000000000 [ 0.678124] x3 : 0000000000000000 x2 : ffffffffffffffff [ 0.678282] x1 : ffffff8008a4e878 x0 : 0000000000000042 [ 0.678442] Call trace: [ 0.678528] Exception stack(0xffffff800800ba00 to 0xffffff800800bb40) [ 0.678706] ba00: 0000000000000042 ffffff8008a4e878 ffffffffffffffff 0000000000000000 [ 0.678914] ba20: 0000000000000000 ffffffc07ffdb9a8 0000000000000017 656b2f2720656d61 [ 0.679121] ba40: ffffff800835d114 00000000000001ac 0000000000000007 00000000000001ab [ 0.679326] ba60: 0000000000000000 0000000000000394 0000000000007fff 0000000000000001 [ 0.679532] ba80: 0000000000000007 0000000000007ffe 0000000000000002 ffffffc07ce67000 [ 0.679739] baa0: ffffffc07c533700 ffffffc07cf26578 ffffffc07cf04598 ffffffc07c532580 [ 0.679944] bac0: ffffff8008af4000 ffffff8008af4ad0 0000000000000000 ffffffc07c52a380 [ 0.680149] bae0: 0000000000000040 ffffff800800bb40 ffffff8008235808 ffffff800800bb40 [ 0.680354] bb00: ffffff8008235808 0000000060000145 ffffffc07c533700 0000000062616c73 [ 0.680560] bb20: ffffffffffffffff 0000000000000000 ffffff800800bb40 ffffff8008235808 [ 0.680774] [<ffffff8008235808>] sysfs_warn_dup+0x60/0x7c [ 0.680928] [<ffffff8008235920>] sysfs_create_dir_ns+0x98/0xa0 [ 0.681095] [<ffffff8008539274>] kobject_add_internal+0xa0/0x294 [ 0.681267] [<ffffff80085394f8>] kobject_init_and_add+0x90/0xb4 [ 0.681435] [<ffffff80081b524c>] sysfs_slab_add+0x90/0x200 [ 0.681592] [<ffffff80081b62a0>] __kmem_cache_create+0x26c/0x438 [ 0.681769] [<ffffff80081858a4>] kmem_cache_create+0x164/0x1f4 [ 0.681940] [<ffffff80086caa98>] sg_pool_init+0x60/0x100 [ 0.682094] [<ffffff8008084144>] do_one_initcall+0x38/0x12c [ 0.682254] [<ffffff80086a0d10>] kernel_init_freeable+0x138/0x1d4 [ 0.682423] [<ffffff8008547388>] kernel_init+0x10/0xfc [ 0.682571] [<ffffff80080851e0>] ret_from_fork+0x10/0x18 Signed-off-by: Miles Chen <[email protected]>

ANBZ: torvalds#442 commit 380a009 upstream. We got issue as follows when run syzkaller: [ 167.936972] EXT4-fs error (device loop0): __ext4_remount:6314: comm rep: Abort forced by user [ 167.938306] EXT4-fs (loop0): Remounting filesystem read-only [ 167.981637] Assertion failure in ext4_getblk() at fs/ext4/inode.c:847: '(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY) || handle != NULL || create == 0' [ 167.983601] ------------[ cut here ]------------ [ 167.984245] kernel BUG at fs/ext4/inode.c:847! [ 167.984882] invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI [ 167.985624] CPU: 7 PID: 2290 Comm: rep Tainted: G B 5.16.0-rc5-next-20211217+ torvalds#123 [ 167.986823] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014 [ 167.988590] RIP: 0010:ext4_getblk+0x17e/0x504 [ 167.989189] Code: c6 01 74 28 49 c7 c0 a0 a3 5c 9b b9 4f 03 00 00 48 c7 c2 80 9c 5c 9b 48 c7 c6 40 b6 5c 9b 48 c7 c7 20 a4 5c 9b e8 77 e3 fd ff <0f> 0b 8b 04 244 [ 167.991679] RSP: 0018:ffff8881736f7398 EFLAGS: 00010282 [ 167.992385] RAX: 0000000000000094 RBX: 1ffff1102e6dee75 RCX: 0000000000000000 [ 167.993337] RDX: 0000000000000001 RSI: ffffffff9b6e29e0 RDI: ffffed102e6dee66 [ 167.994292] RBP: ffff88816a076210 R08: 0000000000000094 R09: ffffed107363fa09 [ 167.995252] R10: ffff88839b1fd047 R11: ffffed107363fa08 R12: ffff88816a0761e8 [ 167.996205] R13: 0000000000000000 R14: 0000000000000021 R15: 0000000000000001 [ 167.997158] FS: 00007f6a1428c740(0000) GS:ffff88839b000000(0000) knlGS:0000000000000000 [ 167.998238] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 167.999025] CR2: 00007f6a140716c8 CR3: 0000000133216000 CR4: 00000000000006e0 [ 167.999987] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 168.000944] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 168.001899] Call Trace: [ 168.002235] <TASK> [ 168.007167] ext4_bread+0xd/0x53 [ 168.007612] ext4_quota_write+0x20c/0x5c0 [ 168.010457] write_blk+0x100/0x220 [ 168.010944] remove_free_dqentry+0x1c6/0x440 [ 168.011525] free_dqentry.isra.0+0x565/0x830 [ 168.012133] remove_tree+0x318/0x6d0 [ 168.014744] remove_tree+0x1eb/0x6d0 [ 168.017346] remove_tree+0x1eb/0x6d0 [ 168.019969] remove_tree+0x1eb/0x6d0 [ 168.022128] qtree_release_dquot+0x291/0x340 [ 168.023297] v2_release_dquot+0xce/0x120 [ 168.023847] dquot_release+0x197/0x3e0 [ 168.024358] ext4_release_dquot+0x22a/0x2d0 [ 168.024932] dqput.part.0+0x1c9/0x900 [ 168.025430] __dquot_drop+0x120/0x190 [ 168.025942] ext4_clear_inode+0x86/0x220 [ 168.026472] ext4_evict_inode+0x9e8/0xa22 [ 168.028200] evict+0x29e/0x4f0 [ 168.028625] dispose_list+0x102/0x1f0 [ 168.029148] evict_inodes+0x2c1/0x3e0 [ 168.030188] generic_shutdown_super+0xa4/0x3b0 [ 168.030817] kill_block_super+0x95/0xd0 [ 168.031360] deactivate_locked_super+0x85/0xd0 [ 168.031977] cleanup_mnt+0x2bc/0x480 [ 168.033062] task_work_run+0xd1/0x170 [ 168.033565] do_exit+0xa4f/0x2b50 [ 168.037155] do_group_exit+0xef/0x2d0 [ 168.037666] __x64_sys_exit_group+0x3a/0x50 [ 168.038237] do_syscall_64+0x3b/0x90 [ 168.038751] entry_SYSCALL_64_after_hwframe+0x44/0xae In order to reproduce this problem, the following conditions need to be met: 1. Ext4 filesystem with no journal; 2. Filesystem image with incorrect quota data; 3. Abort filesystem forced by user; 4. umount filesystem; As in ext4_quota_write: ... if (EXT4_SB(sb)->s_journal && !handle) { ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)" " cancelled because transaction is not started", (unsigned long long)off, (unsigned long long)len); return -EIO; } ... We only check handle if NULL when filesystem has journal. There is need check handle if NULL even when filesystem has no journal. Signed-off-by: Ye Bin <[email protected]> Reviewed-by: Jan Kara <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Theodore Ts'o <[email protected]> Cc: [email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]> Signed-off-by: Hongnan Li <[email protected]> Reviewed-by: Joseph Qi <[email protected]>

Like commit 1cf3bfc ("bpf: Support 64-bit pointers to kfuncs") for s390x, add support for 64-bit pointers to kfuncs for LoongArch. Since the infrastructure is already implemented in BPF core, the only thing need to be done is to override bpf_jit_supports_far_kfunc_call(). Before this change, several test_verifier tests failed: # ./test_verifier | grep # | grep FAIL torvalds#119/p calls: invalid kfunc call: ptr_to_mem to struct with non-scalar FAIL torvalds#120/p calls: invalid kfunc call: ptr_to_mem to struct with nesting depth > 4 FAIL torvalds#121/p calls: invalid kfunc call: ptr_to_mem to struct with FAM FAIL torvalds#122/p calls: invalid kfunc call: reg->type != PTR_TO_CTX FAIL torvalds#123/p calls: invalid kfunc call: void * not allowed in func proto without mem size arg FAIL torvalds#124/p calls: trigger reg2btf_ids[reg->type] for reg->type > __BPF_REG_TYPE_MAX FAIL torvalds#125/p calls: invalid kfunc call: reg->off must be zero when passed to release kfunc FAIL torvalds#126/p calls: invalid kfunc call: don't match first member type when passed to release kfunc FAIL torvalds#127/p calls: invalid kfunc call: PTR_TO_BTF_ID with negative offset FAIL torvalds#128/p calls: invalid kfunc call: PTR_TO_BTF_ID with variable offset FAIL torvalds#129/p calls: invalid kfunc call: referenced arg needs refcounted PTR_TO_BTF_ID FAIL torvalds#130/p calls: valid kfunc call: referenced arg needs refcounted PTR_TO_BTF_ID FAIL torvalds#486/p map_kptr: ref: reference state created and released on xchg FAIL This is because the kfuncs in the loaded module are far away from __bpf_call_base: ffff800002009440 t bpf_kfunc_call_test_fail1 [bpf_testmod] 9000000002e128d8 T __bpf_call_base The offset relative to __bpf_call_base does NOT fit in s32, which breaks the assumption in BPF core. Enable bpf_jit_supports_far_kfunc_call() lifts this limit. Note that to reproduce the above result, tools/testing/selftests/bpf/config should be applied, and run the test with JIT enabled, unpriv BPF enabled. With this change, the test_verifier tests now all passed: # ./test_verifier ... Summary: 777 PASSED, 0 SKIPPED, 0 FAILED Tested-by: Tiezhu Yang <[email protected]> Signed-off-by: Hengqi Chen <[email protected]> Signed-off-by: Huacai Chen <[email protected]>

I hit the following failure when running selftests with internal backported upstream kernel: test_ksyms:PASS:kallsyms_fopen 0 nsec test_ksyms:FAIL:ksym_find symbol 'bpf_link_fops' not found torvalds#123 ksyms:FAIL In /proc/kallsyms, we have $ cat /proc/kallsyms | grep bpf_link_fops ffffffff829f0cb0 d bpf_link_fops.llvm.12608678492448798416 The CONFIG_LTO_CLANG_THIN is enabled in the kernel which is responsible for bpf_link_fops.llvm.12608678492448798416 symbol name. In prog_tests/ksyms.c we have kallsyms_find("bpf_link_fops", &link_fops_addr) and kallsyms_find() compares "bpf_link_fops" with symbols in /proc/kallsyms in order to find the entry. With bpf_link_fops.llvm.<hash> in /proc/kallsyms, the kallsyms_find() failed. To fix the issue, in kallsyms_find(), if a symbol has suffix .llvm.<hash>, that suffix will be ignored for comparison. This fixed the test failure. Signed-off-by: Yonghong Song <[email protected]>

I hit the following failure when running selftests with internal backported upstream kernel: test_ksyms:PASS:kallsyms_fopen 0 nsec test_ksyms:FAIL:ksym_find symbol 'bpf_link_fops' not found torvalds#123 ksyms:FAIL In /proc/kallsyms, we have $ cat /proc/kallsyms | grep bpf_link_fops ffffffff829f0cb0 d bpf_link_fops.llvm.12608678492448798416 The CONFIG_LTO_CLANG_THIN is enabled in the kernel which is responsible for bpf_link_fops.llvm.12608678492448798416 symbol name. In prog_tests/ksyms.c we have kallsyms_find("bpf_link_fops", &link_fops_addr) and kallsyms_find() compares "bpf_link_fops" with symbols in /proc/kallsyms in order to find the entry. With bpf_link_fops.llvm.<hash> in /proc/kallsyms, the kallsyms_find() failed. To fix the issue, in kallsyms_find(), if a symbol has suffix .llvm.<hash>, that suffix will be ignored for comparison. This fixed the test failure. Signed-off-by: Yonghong Song <[email protected]> Signed-off-by: Andrii Nakryiko <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]

Like commit 1cf3bfc ("bpf: Support 64-bit pointers to kfuncs") for s390x, add support for 64-bit pointers to kfuncs for LoongArch. Since the infrastructure is already implemented in BPF core, the only thing need to be done is to override bpf_jit_supports_far_kfunc_call(). Before this change, several test_verifier tests failed: # ./test_verifier | grep # | grep FAIL torvalds#119/p calls: invalid kfunc call: ptr_to_mem to struct with non-scalar FAIL torvalds#120/p calls: invalid kfunc call: ptr_to_mem to struct with nesting depth > 4 FAIL torvalds#121/p calls: invalid kfunc call: ptr_to_mem to struct with FAM FAIL torvalds#122/p calls: invalid kfunc call: reg->type != PTR_TO_CTX FAIL torvalds#123/p calls: invalid kfunc call: void * not allowed in func proto without mem size arg FAIL torvalds#124/p calls: trigger reg2btf_ids[reg->type] for reg->type > __BPF_REG_TYPE_MAX FAIL torvalds#125/p calls: invalid kfunc call: reg->off must be zero when passed to release kfunc FAIL torvalds#126/p calls: invalid kfunc call: don't match first member type when passed to release kfunc FAIL torvalds#127/p calls: invalid kfunc call: PTR_TO_BTF_ID with negative offset FAIL torvalds#128/p calls: invalid kfunc call: PTR_TO_BTF_ID with variable offset FAIL torvalds#129/p calls: invalid kfunc call: referenced arg needs refcounted PTR_TO_BTF_ID FAIL torvalds#130/p calls: valid kfunc call: referenced arg needs refcounted PTR_TO_BTF_ID FAIL torvalds#486/p map_kptr: ref: reference state created and released on xchg FAIL This is because the kfuncs in the loaded module are far away from __bpf_call_base: ffff800002009440 t bpf_kfunc_call_test_fail1 [bpf_testmod] 9000000002e128d8 T __bpf_call_base The offset relative to __bpf_call_base does NOT fit in s32, which breaks the assumption in BPF core. Enable bpf_jit_supports_far_kfunc_call() lifts this limit. Note that to reproduce the above result, tools/testing/selftests/bpf/config should be applied, and run the test with JIT enabled, unpriv BPF enabled. With this change, the test_verifier tests now all passed: # ./test_verifier ... Summary: 777 PASSED, 0 SKIPPED, 0 FAILED Tested-by: Tiezhu Yang <[email protected]> Signed-off-by: Hengqi Chen <[email protected]> Signed-off-by: Huacai Chen <[email protected]>

When trying to insert a 10MB kernel module kept in a virtio-fs with cache disabled, the following warning was reported: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 404 at mm/page_alloc.c:4551 ...... Modules linked in: CPU: 1 PID: 404 Comm: insmod Not tainted 6.9.0-rc5+ torvalds#123 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ...... RIP: 0010:__alloc_pages+0x2bf/0x380 ...... Call Trace: <TASK> ? __warn+0x8e/0x150 ? __alloc_pages+0x2bf/0x380 __kmalloc_large_node+0x86/0x160 __kmalloc+0x33c/0x480 virtio_fs_enqueue_req+0x240/0x6d0 virtio_fs_wake_pending_and_unlock+0x7f/0x190 queue_request_and_unlock+0x55/0x60 fuse_simple_request+0x152/0x2b0 fuse_direct_io+0x5d2/0x8c0 fuse_file_read_iter+0x121/0x160 __kernel_read+0x151/0x2d0 kernel_read+0x45/0x50 kernel_read_file+0x1a9/0x2a0 init_module_from_file+0x6a/0xe0 idempotent_init_module+0x175/0x230 __x64_sys_finit_module+0x5d/0xb0 x64_sys_call+0x1c3/0x9e0 do_syscall_64+0x3d/0xc0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 ...... </TASK> ---[ end trace 0000000000000000 ]--- The warning is triggered as follows: 1) syscall finit_module() handles the module insertion and it invokes kernel_read_file() to read the content of the module first. 2) kernel_read_file() allocates a 10MB buffer by using vmalloc() and passes it to kernel_read(). kernel_read() constructs a kvec iter by using iov_iter_kvec() and passes it to fuse_file_read_iter(). 3) virtio-fs disables the cache, so fuse_file_read_iter() invokes fuse_direct_io(). As for now, the maximal read size for kvec iter is only limited by fc->max_read. For virtio-fs, max_read is UINT_MAX, so fuse_direct_io() doesn't split the 10MB buffer. It saves the address and the size of the 10MB-sized buffer in out_args[0] of a fuse request and passes the fuse request to virtio_fs_wake_pending_and_unlock(). 4) virtio_fs_wake_pending_and_unlock() uses virtio_fs_enqueue_req() to queue the request. Because virtiofs need DMA-able address, so virtio_fs_enqueue_req() uses kmalloc() to allocate a bounce buffer for all fuse args, copies these args into the bounce buffer and passed the physical address of the bounce buffer to virtiofsd. The total length of these fuse args for the passed fuse request is about 10MB, so copy_args_to_argbuf() invokes kmalloc() with a 10MB size parameter and it triggers the warning in __alloc_pages(): if (WARN_ON_ONCE_GFP(order > MAX_PAGE_ORDER, gfp)) return NULL; 5) virtio_fs_enqueue_req() will retry the memory allocation in a kworker, but it won't help, because kmalloc() will always return NULL due to the abnormal size and finit_module() will hang forever. A feasible solution is to limit the value of max_read for virtio-fs, so the length passed to kmalloc() will be limited. However it will affect the maximal read size for normal read. And for virtio-fs write initiated from kernel, it has the similar problem but now there is no way to limit fc->max_write in kernel. So instead of limiting both the values of max_read and max_write in kernel, introducing use_pages_for_kvec_io in fuse_conn and setting it as true in virtiofs. When use_pages_for_kvec_io is enabled, fuse will use pages instead of pointer to pass the KVEC_IO data. After switching to pages for KVEC_IO data, these pages will be used for DMA through virtio-fs. If these pages are backed by vmalloc(), {flush|invalidate}_kernel_vmap_range() are necessary to flush or invalidate the cache before the DMA operation. So add two new fields in fuse_args_pages to record the base address of vmalloc area and the condition indicating whether invalidation is needed. Perform the flush in fuse_get_user_pages() for write operations and the invalidation in fuse_release_user_pages() for read operations. It may seem necessary to introduce another field in fuse_conn to indicate that these KVEC_IO pages are used for DMA, However, considering that virtio-fs is currently the only user of use_pages_for_kvec_io, just reuse use_pages_for_kvec_io to indicate that these pages will be used for DMA. Fixes: a62a8ef ("virtio-fs: add virtiofs filesystem") Signed-off-by: Hou Tao <[email protected]>

When trying to insert a 10MB kernel module kept in a virtio-fs with cache disabled, the following warning was reported: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 404 at mm/page_alloc.c:4551 ...... Modules linked in: CPU: 1 PID: 404 Comm: insmod Not tainted 6.9.0-rc5+ torvalds#123 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ...... RIP: 0010:__alloc_pages+0x2bf/0x380 ...... Call Trace: <TASK> ? __warn+0x8e/0x150 ? __alloc_pages+0x2bf/0x380 __kmalloc_large_node+0x86/0x160 __kmalloc+0x33c/0x480 virtio_fs_enqueue_req+0x240/0x6d0 virtio_fs_wake_pending_and_unlock+0x7f/0x190 queue_request_and_unlock+0x55/0x60 fuse_simple_request+0x152/0x2b0 fuse_direct_io+0x5d2/0x8c0 fuse_file_read_iter+0x121/0x160 __kernel_read+0x151/0x2d0 kernel_read+0x45/0x50 kernel_read_file+0x1a9/0x2a0 init_module_from_file+0x6a/0xe0 idempotent_init_module+0x175/0x230 __x64_sys_finit_module+0x5d/0xb0 x64_sys_call+0x1c3/0x9e0 do_syscall_64+0x3d/0xc0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 ...... </TASK> ---[ end trace 0000000000000000 ]--- The warning is triggered as follows: 1) syscall finit_module() handles the module insertion and it invokes kernel_read_file() to read the content of the module first. 2) kernel_read_file() allocates a 10MB buffer by using vmalloc() and passes it to kernel_read(). kernel_read() constructs a kvec iter by using iov_iter_kvec() and passes it to fuse_file_read_iter(). 3) virtio-fs disables the cache, so fuse_file_read_iter() invokes fuse_direct_io(). As for now, the maximal read size for kvec iter is only limited by fc->max_read. For virtio-fs, max_read is UINT_MAX, so fuse_direct_io() doesn't split the 10MB buffer. It saves the address and the size of the 10MB-sized buffer in out_args[0] of a fuse request and passes the fuse request to virtio_fs_wake_pending_and_unlock(). 4) virtio_fs_wake_pending_and_unlock() uses virtio_fs_enqueue_req() to queue the request. Because virtiofs need DMA-able address, so virtio_fs_enqueue_req() uses kmalloc() to allocate a bounce buffer for all fuse args, copies these args into the bounce buffer and passed the physical address of the bounce buffer to virtiofsd. The total length of these fuse args for the passed fuse request is about 10MB, so copy_args_to_argbuf() invokes kmalloc() with a 10MB size parameter and it triggers the warning in __alloc_pages(): if (WARN_ON_ONCE_GFP(order > MAX_PAGE_ORDER, gfp)) return NULL; 5) virtio_fs_enqueue_req() will retry the memory allocation in a kworker, but it won't help, because kmalloc() will always return NULL due to the abnormal size and finit_module() will hang forever. A feasible solution is to limit the value of max_read for virtio-fs, so the length passed to kmalloc() will be limited. However it will affect the maximal read size for normal read. And for virtio-fs write initiated from kernel, it has the similar problem but now there is no way to limit fc->max_write in kernel. So instead of limiting both the values of max_read and max_write in kernel, introducing use_pages_for_kvec_io in fuse_conn and setting it as true in virtiofs. When use_pages_for_kvec_io is enabled, fuse will use pages instead of pointer to pass the KVEC_IO data. After switching to pages for KVEC_IO data, these pages will be used for DMA through virtio-fs. If these pages are backed by vmalloc(), {flush|invalidate}_kernel_vmap_range() are necessary to flush or invalidate the cache before the DMA operation. So add two new fields in fuse_args_pages to record the base address of vmalloc area and the condition indicating whether invalidation is needed. Perform the flush in fuse_get_user_pages() for write operations and the invalidation in fuse_release_user_pages() for read operations. It may seem necessary to introduce another field in fuse_conn to indicate that these KVEC_IO pages are used for DMA, However, considering that virtio-fs is currently the only user of use_pages_for_kvec_io, just reuse use_pages_for_kvec_io to indicate that these pages will be used for DMA. Fixes: a62a8ef ("virtio-fs: add virtiofs filesystem") Signed-off-by: Hou Tao <[email protected]> Tested-by: Jingbo Xu <[email protected]> Signed-off-by: Miklos Szeredi <[email protected]>

Include tests that check for rejection in erroneous cases, like unbalanced IRQ-disabled counts, within and across subprogs, invalid IRQ flag state or input to kfuncs, behavior upon overwriting IRQ saved state on stack, interaction with sleepable kfuncs/helpers, global functions, and out of order restore. Include some success scenarios as well to demonstrate usage. torvalds#123/1 irq/irq_restore_missing_1:OK torvalds#123/2 irq/irq_restore_missing_2:OK torvalds#123/3 irq/irq_restore_missing_3:OK torvalds#123/4 irq/irq_restore_missing_3_minus_2:OK torvalds#123/5 irq/irq_restore_missing_1_subprog:OK torvalds#123/6 irq/irq_restore_missing_2_subprog:OK torvalds#123/7 irq/irq_restore_missing_3_subprog:OK torvalds#123/8 irq/irq_restore_missing_3_minus_2_subprog:OK torvalds#123/9 irq/irq_balance:OK torvalds#123/10 irq/irq_balance_n:OK torvalds#123/11 irq/irq_balance_subprog:OK torvalds#123/12 irq/irq_balance_n_subprog:OK torvalds#123/13 irq/irq_global_subprog:OK torvalds#123/14 irq/irq_restore_ooo:OK torvalds#123/15 irq/irq_restore_ooo_3:OK torvalds#123/16 irq/irq_restore_3_subprog:OK torvalds#123/17 irq/irq_restore_4_subprog:OK torvalds#123/18 irq/irq_restore_ooo_3_subprog:OK torvalds#123/19 irq/irq_restore_invalid:OK torvalds#123/20 irq/irq_save_invalid:OK torvalds#123/21 irq/irq_restore_iter:OK torvalds#123/22 irq/irq_save_iter:OK torvalds#123/23 irq/irq_flag_overwrite:OK torvalds#123/24 irq/irq_flag_overwrite_partial:OK torvalds#123/25 irq/irq_sleepable_helper:OK torvalds#123/26 irq/irq_sleepable_kfunc:OK torvalds#123 irq:OK Summary: 1/26 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Kumar Kartikeya Dwivedi <[email protected]>

Merge pull request #1 from torvalds/master

aeb978c

pulling latest linux code

rakesh-gopal closed this Sep 19, 2014

xin3liang pushed a commit to xin3liang/linux that referenced this pull request Oct 16, 2015

Merge pull request torvalds#123 from hzhuang1/spi_pinmux

0dfba97

arm64: hi6220: add spi0 pinmux definition

laijs pushed a commit to laijs/linux that referenced this pull request Feb 13, 2017

Merge pull request torvalds#123 from ngkaho1234/fix-sem-fault

41efdf8

lkl: fix wakeup_cpu trashing the heap of host memory allocator.

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Merge pull request #1 from torvalds/master #123

Merge pull request #1 from torvalds/master #123

rakesh-gopal commented Sep 19, 2014

Merge pull request #1 from torvalds/master #123

Merge pull request #1 from torvalds/master #123

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rakesh-gopal commented Sep 19, 2014