Replaced the Code of Conduct with the Code of Conflict #599

AshtonSnapp · 2018-09-26T00:19:26Z

Due to the amount of controversy following the installation of the Code of Conduct, I am opening this pull request to replace it with the original Code of Conflict, to, as put by Joey Pabalinas, "Unfuck our Codes of Conduct", and to stop the controversy and drama (two things I never liked).

Removed the Code of Conduct. Brought back the Code of Conflict.

KernelPRBot · 2018-09-26T00:19:36Z

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SteveHeist · 2018-09-26T05:41:27Z

I'd vote in favor of #594 - does the same thing

0x0000F1 · 2018-09-26T16:13:40Z

@SteveHeist I would vote for anything that gets us back on track

felipemullen · 2018-09-27T05:23:08Z

yes, and #593

ghost · 2018-09-27T13:44:35Z

I agree.
We have many people committing from different backgrounds all over the world, because of this people hold their own ideals. This could prevent a patch being made just because the committer holds ideals that conflicts with the CoC. Not to mention some people that make commits might not have a lot of social experience or may interpret things differently than others. Some people have a hard time distinguishing right from wrong, but should we be exiling or denying them just because we think something is right? If you want to be inclusive you want free flow of thought. The CoC imposes that gender, sex, race is relevant to committing to a open source project, but this counterproductive. If we just ignore the fact that we are different then people will treat each other the same not the other way around because by identifying with a group you create exclusiveness.

felipemullen · 2018-09-27T14:46:42Z

@SilicaAndPina thanks for sharing that, it really opened my eyes...

Have the rest of you read the things CoralineAda say? I'm seriously at a loss for words. It's just pure hate and malice.

Is this what we are supposed to stand by? Because I won't. I choose to respect ALL people. Not a chosen inside group that aligns with my own world views.

This commit fixes the following checkpatch.pl errors: ERROR:POINTER_LOCATION: "foo* bar" should be "foo *bar" torvalds#307: FILE: ./include/rtw_mlme_ext.h:307: + char* str; ERROR:POINTER_LOCATION: "foo* bar" should be "foo *bar" torvalds#313: FILE: ./include/rtw_mlme_ext.h:313: + char* str; ERROR:POINTER_LOCATION: "foo * bar" should be "foo *bar" torvalds#592: FILE: ./include/rtw_mlme_ext.h:592: +int WMM_param_handler(struct adapter *padapter, struct ndis_80211_var_ie * pIE); ERROR:POINTER_LOCATION: "foo * bar" should be "foo *bar" torvalds#595: FILE: ./include/rtw_mlme_ext.h:595: +void HT_caps_handler(struct adapter *padapter, struct ndis_80211_var_ie * pIE); ERROR:POINTER_LOCATION: "foo * bar" should be "foo *bar" torvalds#596: FILE: ./include/rtw_mlme_ext.h:596: +void HT_info_handler(struct adapter *padapter, struct ndis_80211_var_ie * pIE); ERROR:POINTER_LOCATION: "foo * bar" should be "foo *bar" torvalds#599: FILE: ./include/rtw_mlme_ext.h:599: +void ERP_IE_handler(struct adapter *padapter, struct ndis_80211_var_ie * pIE); ERROR:POINTER_LOCATION: "foo * bar" should be "foo *bar" torvalds#606: FILE: ./include/rtw_mlme_ext.h:606: +void update_capinfo(struct adapter * Adapter, u16 updateCap); ERROR:POINTER_LOCATION: "foo* bar" should be "foo *bar" torvalds#633: FILE: ./include/rtw_mlme_ext.h:633: +void report_del_sta_event(struct adapter *padapter, unsigned char* MacAddr, unsigned short reason); ERROR:POINTER_LOCATION: "foo* bar" should be "foo *bar" torvalds#634: FILE: ./include/rtw_mlme_ext.h:634: +void report_add_sta_event(struct adapter *padapter, unsigned char* MacAddr, int cam_idx); Signed-off-by: Marco Cesati <marcocesati@gmail.com>

This commit fixes the following checkpatch.pl errors: ERROR:POINTER_LOCATION: "foo* bar" should be "foo *bar" torvalds#307: FILE: ./include/rtw_mlme_ext.h:307: + char* str; ERROR:POINTER_LOCATION: "foo* bar" should be "foo *bar" torvalds#313: FILE: ./include/rtw_mlme_ext.h:313: + char* str; ERROR:POINTER_LOCATION: "foo * bar" should be "foo *bar" torvalds#592: FILE: ./include/rtw_mlme_ext.h:592: +int WMM_param_handler(struct adapter *padapter, struct ndis_80211_var_ie * pIE); ERROR:POINTER_LOCATION: "foo * bar" should be "foo *bar" torvalds#595: FILE: ./include/rtw_mlme_ext.h:595: +void HT_caps_handler(struct adapter *padapter, struct ndis_80211_var_ie * pIE); ERROR:POINTER_LOCATION: "foo * bar" should be "foo *bar" torvalds#596: FILE: ./include/rtw_mlme_ext.h:596: +void HT_info_handler(struct adapter *padapter, struct ndis_80211_var_ie * pIE); ERROR:POINTER_LOCATION: "foo * bar" should be "foo *bar" torvalds#599: FILE: ./include/rtw_mlme_ext.h:599: +void ERP_IE_handler(struct adapter *padapter, struct ndis_80211_var_ie * pIE); ERROR:POINTER_LOCATION: "foo * bar" should be "foo *bar" torvalds#606: FILE: ./include/rtw_mlme_ext.h:606: +void update_capinfo(struct adapter * Adapter, u16 updateCap); ERROR:POINTER_LOCATION: "foo* bar" should be "foo *bar" torvalds#633: FILE: ./include/rtw_mlme_ext.h:633: +void report_del_sta_event(struct adapter *padapter, unsigned char* MacAddr, unsigned short reason); ERROR:POINTER_LOCATION: "foo* bar" should be "foo *bar" torvalds#634: FILE: ./include/rtw_mlme_ext.h:634: +void report_add_sta_event(struct adapter *padapter, unsigned char* MacAddr, int cam_idx); Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Marco Cesati <marcocesati@gmail.com> Link: https://lore.kernel.org/r/20210315170618.2566-54-marcocesati@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Fixs two error: "ERROR: do not use assignment in if condition torvalds#130: FILE: io_uring/net.c:130: + if (!(issue_flags & IO_URING_F_UNLOCKED) && ERROR: do not use assignment in if condition torvalds#599: FILE: io_uring/poll.c:599: + } else if (!(issue_flags & IO_URING_F_UNLOCKED) &&" reported by checkpatch.pl in net.c and poll.c . Signed-off-by: Xinghui Li <korantli@tencent.com>

PD#151225: driver defect clean up: torvalds#228 torvalds#262 torvalds#354 torvalds#407 torvalds#442 torvalds#445 torvalds#461 torvalds#576 torvalds#580 torvalds#598 torvalds#599 torvalds#615 torvalds#616 torvalds#671 torvalds#756 torvalds#760 torvalds#874 Change-Id: I1bc47c3e30ecfa1ca44e53f91201aa4e09ff19f5 Signed-off-by: Bencheng Jing <bencheng.jing@amlogic.com>

The hwnoise tool is a special mode for the osnoise top tool. hwnoise dispatches the osnoise tracer and displays a summary of the noise. The difference is that it runs the tracer with the OSNOISE_IRQ_DISABLE option set, thus only allowing only hardware-related noise, resulting in a simplified output. hwnoise has the same features of osnoise. An example of the tool's output: # rtla hwnoise -c 1-11 -T 1 -d 10m -q Hardware-related Noise duration: 0 00:10:00 | time is in us CPU Period Runtime Noise % CPU Aval Max Noise Max Single HW NMI 1 torvalds#599 599000000 138 99.99997 3 3 4 74 2 torvalds#599 599000000 85 99.99998 3 3 4 75 3 torvalds#599 599000000 86 99.99998 4 3 6 75 4 torvalds#599 599000000 81 99.99998 4 4 2 75 5 torvalds#599 599000000 85 99.99998 2 2 2 75 Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jonathan Corbet <corbet@lwn.net>

The hwnoise tool is a special mode for the osnoise top tool. hwnoise dispatches the osnoise tracer and displays a summary of the noise. The difference is that it runs the tracer with the OSNOISE_IRQ_DISABLE option set, thus only allowing only hardware-related noise, resulting in a simplified output. hwnoise has the same features of osnoise. An example of the tool's output: # rtla hwnoise -c 1-5 -T 1 -d 10m -q Hardware-related Noise duration: 0 00:10:00 | time is in us CPU Period Runtime Noise % CPU Aval Max Noise Max Single HW NMI 1 torvalds#599 599000000 138 99.99997 3 3 4 74 2 torvalds#599 599000000 85 99.99998 3 3 4 75 3 torvalds#599 599000000 86 99.99998 4 3 6 75 4 torvalds#599 599000000 81 99.99998 4 4 2 75 5 torvalds#599 599000000 85 99.99998 2 2 2 75 Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jonathan Corbet <corbet@lwn.net>

The hwnoise tool is a special mode for the osnoise top tool. hwnoise dispatches the osnoise tracer and displays a summary of the noise. The difference is that it runs the tracer with the OSNOISE_IRQ_DISABLE option set, thus only allowing only hardware-related noise, resulting in a simplified output. hwnoise has the same features of osnoise. An example of the tool's output: # rtla hwnoise -c 1-11 -T 1 -d 10m -q Hardware-related Noise duration: 0 00:10:00 | time is in us CPU Period Runtime Noise % CPU Aval Max Noise Max Single HW NMI 1 torvalds#599 599000000 138 99.99997 3 3 4 74 2 torvalds#599 599000000 85 99.99998 3 3 4 75 3 torvalds#599 599000000 86 99.99998 4 3 6 75 4 torvalds#599 599000000 81 99.99998 4 4 2 75 5 torvalds#599 599000000 85 99.99998 2 2 2 75 Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jonathan Corbet <corbet@lwn.net>

The hwnoise tool is a special mode for the osnoise top tool. hwnoise dispatches the osnoise tracer and displays a summary of the noise. The difference is that it runs the tracer with the OSNOISE_IRQ_DISABLE option set, thus only allowing only hardware-related noise, resulting in a simplified output. hwnoise has the same features of osnoise. An example of the tool's output: # rtla hwnoise -c 1-11 -T 1 -d 10m -q Hardware-related Noise duration: 0 00:10:00 | time is in us CPU Period Runtime Noise % CPU Aval Max Noise Max Single HW NMI 1 torvalds#599 599000000 138 99.99997 3 3 4 74 2 torvalds#599 599000000 85 99.99998 3 3 4 75 3 torvalds#599 599000000 86 99.99998 4 3 6 75 4 torvalds#599 599000000 81 99.99998 4 4 2 75 5 torvalds#599 599000000 85 99.99998 2 2 2 75 Link: https://lkml.kernel.org/r/2d6f49a6f3a4f8b51b2c806458b1cff71ad4d014.1675805361.git.bristot@kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Bagas Sanjaya <bagasdotme@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Running fstests btrfs/011 with MKFS_OPTIONS="-O rst" to force the usage of the RAID stripe-tree, we get the following splat from lockdep: BTRFS info (device sdd): dev_replace from /dev/sdd (devid 1) to /dev/sdb started ============================================ WARNING: possible recursive locking detected 6.11.0-rc3-btrfs-for-next torvalds#599 Not tainted -------------------------------------------- btrfs/2326 is trying to acquire lock: ffff88810f215c98 (&fs_info->dev_replace.rwsem){++++}-{3:3}, at: btrfs_map_block+0x39f/0x2250 but task is already holding lock: ffff88810f215c98 (&fs_info->dev_replace.rwsem){++++}-{3:3}, at: btrfs_map_block+0x39f/0x2250 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&fs_info->dev_replace.rwsem); lock(&fs_info->dev_replace.rwsem); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by btrfs/2326: #0: ffff88810f215c98 (&fs_info->dev_replace.rwsem){++++}-{3:3}, at: btrfs_map_block+0x39f/0x2250 stack backtrace: CPU: 1 UID: 0 PID: 2326 Comm: btrfs Not tainted 6.11.0-rc3-btrfs-for-next torvalds#599 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Call Trace: <TASK> dump_stack_lvl+0x5b/0x80 __lock_acquire+0x2798/0x69d0 ? __pfx___lock_acquire+0x10/0x10 ? __pfx___lock_acquire+0x10/0x10 lock_acquire+0x19d/0x4a0 ? btrfs_map_block+0x39f/0x2250 ? __pfx_lock_acquire+0x10/0x10 ? find_held_lock+0x2d/0x110 ? lock_is_held_type+0x8f/0x100 down_read+0x8e/0x440 ? btrfs_map_block+0x39f/0x2250 ? __pfx_down_read+0x10/0x10 ? do_raw_read_unlock+0x44/0x70 ? _raw_read_unlock+0x23/0x40 btrfs_map_block+0x39f/0x2250 ? btrfs_dev_replace_by_ioctl+0xd69/0x1d00 ? btrfs_bio_counter_inc_blocked+0xd9/0x2e0 ? __kasan_slab_alloc+0x6e/0x70 ? __pfx_btrfs_map_block+0x10/0x10 ? __pfx_btrfs_bio_counter_inc_blocked+0x10/0x10 ? kmem_cache_alloc_noprof+0x1f2/0x300 ? mempool_alloc_noprof+0xed/0x2b0 btrfs_submit_chunk+0x28d/0x17e0 ? __pfx_btrfs_submit_chunk+0x10/0x10 ? bvec_alloc+0xd7/0x1b0 ? bio_add_folio+0x171/0x270 ? __pfx_bio_add_folio+0x10/0x10 ? __kasan_check_read+0x20/0x20 btrfs_submit_bio+0x37/0x80 read_extent_buffer_pages+0x3df/0x6c0 btrfs_read_extent_buffer+0x13e/0x5f0 read_tree_block+0x81/0xe0 read_block_for_search+0x4bd/0x7a0 ? __pfx_read_block_for_search+0x10/0x10 btrfs_search_slot+0x78d/0x2720 ? __pfx_btrfs_search_slot+0x10/0x10 ? lock_is_held_type+0x8f/0x100 ? kasan_save_track+0x14/0x30 ? __kasan_slab_alloc+0x6e/0x70 ? kmem_cache_alloc_noprof+0x1f2/0x300 btrfs_get_raid_extent_offset+0x181/0x820 ? __pfx_lock_acquire+0x10/0x10 ? __pfx_btrfs_get_raid_extent_offset+0x10/0x10 ? down_read+0x194/0x440 ? __pfx_down_read+0x10/0x10 ? do_raw_read_unlock+0x44/0x70 ? _raw_read_unlock+0x23/0x40 btrfs_map_block+0x5b5/0x2250 ? __pfx_btrfs_map_block+0x10/0x10 scrub_submit_initial_read+0x8fe/0x11b0 ? __pfx_scrub_submit_initial_read+0x10/0x10 submit_initial_group_read+0x161/0x3a0 ? lock_release+0x20e/0x710 ? __pfx_submit_initial_group_read+0x10/0x10 ? __pfx_lock_release+0x10/0x10 scrub_simple_mirror.isra.0+0x3eb/0x580 scrub_stripe+0xe4d/0x1440 ? lock_release+0x20e/0x710 ? __pfx_scrub_stripe+0x10/0x10 ? __pfx_lock_release+0x10/0x10 ? do_raw_read_unlock+0x44/0x70 ? _raw_read_unlock+0x23/0x40 scrub_chunk+0x257/0x4a0 scrub_enumerate_chunks+0x64c/0xf70 ? __mutex_unlock_slowpath+0x147/0x5f0 ? __pfx_scrub_enumerate_chunks+0x10/0x10 ? bit_wait_timeout+0xb0/0x170 ? __up_read+0x189/0x700 ? scrub_workers_get+0x231/0x300 ? up_write+0x490/0x4f0 btrfs_scrub_dev+0x52e/0xcd0 ? create_pending_snapshots+0x230/0x250 ? __pfx_btrfs_scrub_dev+0x10/0x10 btrfs_dev_replace_by_ioctl+0xd69/0x1d00 ? lock_acquire+0x19d/0x4a0 ? __pfx_btrfs_dev_replace_by_ioctl+0x10/0x10 ? lock_release+0x20e/0x710 ? btrfs_ioctl+0xa09/0x74f0 ? __pfx_lock_release+0x10/0x10 ? do_raw_spin_lock+0x11e/0x240 ? __pfx_do_raw_spin_lock+0x10/0x10 btrfs_ioctl+0xa14/0x74f0 ? lock_acquire+0x19d/0x4a0 ? find_held_lock+0x2d/0x110 ? __pfx_btrfs_ioctl+0x10/0x10 ? lock_release+0x20e/0x710 ? do_sigaction+0x3f0/0x860 ? __pfx_do_vfs_ioctl+0x10/0x10 ? do_raw_spin_lock+0x11e/0x240 ? lockdep_hardirqs_on_prepare+0x270/0x3e0 ? _raw_spin_unlock_irq+0x28/0x50 ? do_sigaction+0x3f0/0x860 ? __pfx_do_sigaction+0x10/0x10 ? __x64_sys_rt_sigaction+0x18e/0x1e0 ? __pfx___x64_sys_rt_sigaction+0x10/0x10 ? __x64_sys_close+0x7c/0xd0 __x64_sys_ioctl+0x137/0x190 do_syscall_64+0x71/0x140 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f0bd1114f9b Code: Unable to access opcode bytes at 0x7f0bd1114f71. RSP: 002b:00007ffc8a8c3130 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f0bd1114f9b RDX: 00007ffc8a8c35e0 RSI: 00000000ca289435 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000007 R10: 0000000000000008 R11: 0000000000000246 R12: 00007ffc8a8c6c85 R13: 00000000398e72a0 R14: 0000000000004361 R15: 0000000000000004 </TASK> This happens because on RAID stripe-tree filesystems we recurse back into btrfs_map_block() on scrub to perform the logical to device physical mapping. But as the device replace task is already holding the dev_replace::rwsem we deadlock. So don't take the dev_replace::rwsem in case our task is the task performing the device replace. Suggested-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>

Running fstests btrfs/011 with MKFS_OPTIONS="-O rst" to force the usage of the RAID stripe-tree, we get the following splat from lockdep: BTRFS info (device sdd): dev_replace from /dev/sdd (devid 1) to /dev/sdb started ============================================ WARNING: possible recursive locking detected 6.11.0-rc3-btrfs-for-next torvalds#599 Not tainted -------------------------------------------- btrfs/2326 is trying to acquire lock: ffff88810f215c98 (&fs_info->dev_replace.rwsem){++++}-{3:3}, at: btrfs_map_block+0x39f/0x2250 but task is already holding lock: ffff88810f215c98 (&fs_info->dev_replace.rwsem){++++}-{3:3}, at: btrfs_map_block+0x39f/0x2250 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&fs_info->dev_replace.rwsem); lock(&fs_info->dev_replace.rwsem); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by btrfs/2326: #0: ffff88810f215c98 (&fs_info->dev_replace.rwsem){++++}-{3:3}, at: btrfs_map_block+0x39f/0x2250 stack backtrace: CPU: 1 UID: 0 PID: 2326 Comm: btrfs Not tainted 6.11.0-rc3-btrfs-for-next torvalds#599 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Call Trace: <TASK> dump_stack_lvl+0x5b/0x80 __lock_acquire+0x2798/0x69d0 ? __pfx___lock_acquire+0x10/0x10 ? __pfx___lock_acquire+0x10/0x10 lock_acquire+0x19d/0x4a0 ? btrfs_map_block+0x39f/0x2250 ? __pfx_lock_acquire+0x10/0x10 ? find_held_lock+0x2d/0x110 ? lock_is_held_type+0x8f/0x100 down_read+0x8e/0x440 ? btrfs_map_block+0x39f/0x2250 ? __pfx_down_read+0x10/0x10 ? do_raw_read_unlock+0x44/0x70 ? _raw_read_unlock+0x23/0x40 btrfs_map_block+0x39f/0x2250 ? btrfs_dev_replace_by_ioctl+0xd69/0x1d00 ? btrfs_bio_counter_inc_blocked+0xd9/0x2e0 ? __kasan_slab_alloc+0x6e/0x70 ? __pfx_btrfs_map_block+0x10/0x10 ? __pfx_btrfs_bio_counter_inc_blocked+0x10/0x10 ? kmem_cache_alloc_noprof+0x1f2/0x300 ? mempool_alloc_noprof+0xed/0x2b0 btrfs_submit_chunk+0x28d/0x17e0 ? __pfx_btrfs_submit_chunk+0x10/0x10 ? bvec_alloc+0xd7/0x1b0 ? bio_add_folio+0x171/0x270 ? __pfx_bio_add_folio+0x10/0x10 ? __kasan_check_read+0x20/0x20 btrfs_submit_bio+0x37/0x80 read_extent_buffer_pages+0x3df/0x6c0 btrfs_read_extent_buffer+0x13e/0x5f0 read_tree_block+0x81/0xe0 read_block_for_search+0x4bd/0x7a0 ? __pfx_read_block_for_search+0x10/0x10 btrfs_search_slot+0x78d/0x2720 ? __pfx_btrfs_search_slot+0x10/0x10 ? lock_is_held_type+0x8f/0x100 ? kasan_save_track+0x14/0x30 ? __kasan_slab_alloc+0x6e/0x70 ? kmem_cache_alloc_noprof+0x1f2/0x300 btrfs_get_raid_extent_offset+0x181/0x820 ? __pfx_lock_acquire+0x10/0x10 ? __pfx_btrfs_get_raid_extent_offset+0x10/0x10 ? down_read+0x194/0x440 ? __pfx_down_read+0x10/0x10 ? do_raw_read_unlock+0x44/0x70 ? _raw_read_unlock+0x23/0x40 btrfs_map_block+0x5b5/0x2250 ? __pfx_btrfs_map_block+0x10/0x10 scrub_submit_initial_read+0x8fe/0x11b0 ? __pfx_scrub_submit_initial_read+0x10/0x10 submit_initial_group_read+0x161/0x3a0 ? lock_release+0x20e/0x710 ? __pfx_submit_initial_group_read+0x10/0x10 ? __pfx_lock_release+0x10/0x10 scrub_simple_mirror.isra.0+0x3eb/0x580 scrub_stripe+0xe4d/0x1440 ? lock_release+0x20e/0x710 ? __pfx_scrub_stripe+0x10/0x10 ? __pfx_lock_release+0x10/0x10 ? do_raw_read_unlock+0x44/0x70 ? _raw_read_unlock+0x23/0x40 scrub_chunk+0x257/0x4a0 scrub_enumerate_chunks+0x64c/0xf70 ? __mutex_unlock_slowpath+0x147/0x5f0 ? __pfx_scrub_enumerate_chunks+0x10/0x10 ? bit_wait_timeout+0xb0/0x170 ? __up_read+0x189/0x700 ? scrub_workers_get+0x231/0x300 ? up_write+0x490/0x4f0 btrfs_scrub_dev+0x52e/0xcd0 ? create_pending_snapshots+0x230/0x250 ? __pfx_btrfs_scrub_dev+0x10/0x10 btrfs_dev_replace_by_ioctl+0xd69/0x1d00 ? lock_acquire+0x19d/0x4a0 ? __pfx_btrfs_dev_replace_by_ioctl+0x10/0x10 ? lock_release+0x20e/0x710 ? btrfs_ioctl+0xa09/0x74f0 ? __pfx_lock_release+0x10/0x10 ? do_raw_spin_lock+0x11e/0x240 ? __pfx_do_raw_spin_lock+0x10/0x10 btrfs_ioctl+0xa14/0x74f0 ? lock_acquire+0x19d/0x4a0 ? find_held_lock+0x2d/0x110 ? __pfx_btrfs_ioctl+0x10/0x10 ? lock_release+0x20e/0x710 ? do_sigaction+0x3f0/0x860 ? __pfx_do_vfs_ioctl+0x10/0x10 ? do_raw_spin_lock+0x11e/0x240 ? lockdep_hardirqs_on_prepare+0x270/0x3e0 ? _raw_spin_unlock_irq+0x28/0x50 ? do_sigaction+0x3f0/0x860 ? __pfx_do_sigaction+0x10/0x10 ? __x64_sys_rt_sigaction+0x18e/0x1e0 ? __pfx___x64_sys_rt_sigaction+0x10/0x10 ? __x64_sys_close+0x7c/0xd0 __x64_sys_ioctl+0x137/0x190 do_syscall_64+0x71/0x140 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f0bd1114f9b Code: Unable to access opcode bytes at 0x7f0bd1114f71. RSP: 002b:00007ffc8a8c3130 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f0bd1114f9b RDX: 00007ffc8a8c35e0 RSI: 00000000ca289435 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000007 R10: 0000000000000008 R11: 0000000000000246 R12: 00007ffc8a8c6c85 R13: 00000000398e72a0 R14: 0000000000004361 R15: 0000000000000004 </TASK> This happens because on RAID stripe-tree filesystems we recurse back into btrfs_map_block() on scrub to perform the logical to device physical mapping. But as the device replace task is already holding the dev_replace::rwsem we deadlock. So don't take the dev_replace::rwsem in case our task is the task performing the device replace. Suggested-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Filipe Manana <fdmanana@suse.com>

Running fstests btrfs/011 with MKFS_OPTIONS="-O rst" to force the usage of the RAID stripe-tree, we get the following splat from lockdep: BTRFS info (device sdd): dev_replace from /dev/sdd (devid 1) to /dev/sdb started ============================================ WARNING: possible recursive locking detected 6.11.0-rc3-btrfs-for-next torvalds#599 Not tainted -------------------------------------------- btrfs/2326 is trying to acquire lock: ffff88810f215c98 (&fs_info->dev_replace.rwsem){++++}-{3:3}, at: btrfs_map_block+0x39f/0x2250 but task is already holding lock: ffff88810f215c98 (&fs_info->dev_replace.rwsem){++++}-{3:3}, at: btrfs_map_block+0x39f/0x2250 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&fs_info->dev_replace.rwsem); lock(&fs_info->dev_replace.rwsem); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by btrfs/2326: #0: ffff88810f215c98 (&fs_info->dev_replace.rwsem){++++}-{3:3}, at: btrfs_map_block+0x39f/0x2250 stack backtrace: CPU: 1 UID: 0 PID: 2326 Comm: btrfs Not tainted 6.11.0-rc3-btrfs-for-next torvalds#599 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Call Trace: <TASK> dump_stack_lvl+0x5b/0x80 __lock_acquire+0x2798/0x69d0 ? __pfx___lock_acquire+0x10/0x10 ? __pfx___lock_acquire+0x10/0x10 lock_acquire+0x19d/0x4a0 ? btrfs_map_block+0x39f/0x2250 ? __pfx_lock_acquire+0x10/0x10 ? find_held_lock+0x2d/0x110 ? lock_is_held_type+0x8f/0x100 down_read+0x8e/0x440 ? btrfs_map_block+0x39f/0x2250 ? __pfx_down_read+0x10/0x10 ? do_raw_read_unlock+0x44/0x70 ? _raw_read_unlock+0x23/0x40 btrfs_map_block+0x39f/0x2250 ? btrfs_dev_replace_by_ioctl+0xd69/0x1d00 ? btrfs_bio_counter_inc_blocked+0xd9/0x2e0 ? __kasan_slab_alloc+0x6e/0x70 ? __pfx_btrfs_map_block+0x10/0x10 ? __pfx_btrfs_bio_counter_inc_blocked+0x10/0x10 ? kmem_cache_alloc_noprof+0x1f2/0x300 ? mempool_alloc_noprof+0xed/0x2b0 btrfs_submit_chunk+0x28d/0x17e0 ? __pfx_btrfs_submit_chunk+0x10/0x10 ? bvec_alloc+0xd7/0x1b0 ? bio_add_folio+0x171/0x270 ? __pfx_bio_add_folio+0x10/0x10 ? __kasan_check_read+0x20/0x20 btrfs_submit_bio+0x37/0x80 read_extent_buffer_pages+0x3df/0x6c0 btrfs_read_extent_buffer+0x13e/0x5f0 read_tree_block+0x81/0xe0 read_block_for_search+0x4bd/0x7a0 ? __pfx_read_block_for_search+0x10/0x10 btrfs_search_slot+0x78d/0x2720 ? __pfx_btrfs_search_slot+0x10/0x10 ? lock_is_held_type+0x8f/0x100 ? kasan_save_track+0x14/0x30 ? __kasan_slab_alloc+0x6e/0x70 ? kmem_cache_alloc_noprof+0x1f2/0x300 btrfs_get_raid_extent_offset+0x181/0x820 ? __pfx_lock_acquire+0x10/0x10 ? __pfx_btrfs_get_raid_extent_offset+0x10/0x10 ? down_read+0x194/0x440 ? __pfx_down_read+0x10/0x10 ? do_raw_read_unlock+0x44/0x70 ? _raw_read_unlock+0x23/0x40 btrfs_map_block+0x5b5/0x2250 ? __pfx_btrfs_map_block+0x10/0x10 scrub_submit_initial_read+0x8fe/0x11b0 ? __pfx_scrub_submit_initial_read+0x10/0x10 submit_initial_group_read+0x161/0x3a0 ? lock_release+0x20e/0x710 ? __pfx_submit_initial_group_read+0x10/0x10 ? __pfx_lock_release+0x10/0x10 scrub_simple_mirror.isra.0+0x3eb/0x580 scrub_stripe+0xe4d/0x1440 ? lock_release+0x20e/0x710 ? __pfx_scrub_stripe+0x10/0x10 ? __pfx_lock_release+0x10/0x10 ? do_raw_read_unlock+0x44/0x70 ? _raw_read_unlock+0x23/0x40 scrub_chunk+0x257/0x4a0 scrub_enumerate_chunks+0x64c/0xf70 ? __mutex_unlock_slowpath+0x147/0x5f0 ? __pfx_scrub_enumerate_chunks+0x10/0x10 ? bit_wait_timeout+0xb0/0x170 ? __up_read+0x189/0x700 ? scrub_workers_get+0x231/0x300 ? up_write+0x490/0x4f0 btrfs_scrub_dev+0x52e/0xcd0 ? create_pending_snapshots+0x230/0x250 ? __pfx_btrfs_scrub_dev+0x10/0x10 btrfs_dev_replace_by_ioctl+0xd69/0x1d00 ? lock_acquire+0x19d/0x4a0 ? __pfx_btrfs_dev_replace_by_ioctl+0x10/0x10 ? lock_release+0x20e/0x710 ? btrfs_ioctl+0xa09/0x74f0 ? __pfx_lock_release+0x10/0x10 ? do_raw_spin_lock+0x11e/0x240 ? __pfx_do_raw_spin_lock+0x10/0x10 btrfs_ioctl+0xa14/0x74f0 ? lock_acquire+0x19d/0x4a0 ? find_held_lock+0x2d/0x110 ? __pfx_btrfs_ioctl+0x10/0x10 ? lock_release+0x20e/0x710 ? do_sigaction+0x3f0/0x860 ? __pfx_do_vfs_ioctl+0x10/0x10 ? do_raw_spin_lock+0x11e/0x240 ? lockdep_hardirqs_on_prepare+0x270/0x3e0 ? _raw_spin_unlock_irq+0x28/0x50 ? do_sigaction+0x3f0/0x860 ? __pfx_do_sigaction+0x10/0x10 ? __x64_sys_rt_sigaction+0x18e/0x1e0 ? __pfx___x64_sys_rt_sigaction+0x10/0x10 ? __x64_sys_close+0x7c/0xd0 __x64_sys_ioctl+0x137/0x190 do_syscall_64+0x71/0x140 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f0bd1114f9b Code: Unable to access opcode bytes at 0x7f0bd1114f71. RSP: 002b:00007ffc8a8c3130 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f0bd1114f9b RDX: 00007ffc8a8c35e0 RSI: 00000000ca289435 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000007 R10: 0000000000000008 R11: 0000000000000246 R12: 00007ffc8a8c6c85 R13: 00000000398e72a0 R14: 0000000000004361 R15: 0000000000000004 </TASK> This happens because on RAID stripe-tree filesystems we recurse back into btrfs_map_block() on scrub to perform the logical to device physical mapping. But as the device replace task is already holding the dev_replace::rwsem we deadlock. So don't take the dev_replace::rwsem in case our task is the task performing the device replace. Suggested-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>

AshtonSnapp added 2 commits September 25, 2018 19:12

Fixed the CoC by bringing the original back

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Removed the Code of Conduct. Brought back the Code of Conflict.

Removed my little message

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alandoni approved these changes Sep 27, 2018

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Replaced the Code of Conduct with the Code of Conflict #599

Replaced the Code of Conduct with the Code of Conflict #599

AshtonSnapp commented Sep 26, 2018

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felipemullen commented Sep 27, 2018

ghost commented Sep 27, 2018

felipemullen commented Sep 27, 2018 •

edited

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Replaced the Code of Conduct with the Code of Conflict #599

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Replaced the Code of Conduct with the Code of Conflict #599

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SteveHeist commented Sep 26, 2018

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felipemullen commented Sep 27, 2018 •

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