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possible deadlock in xfs_vn_update_time

Status: upstream: reported on 2024/12/12 22:41
Subsystems: block
[Documentation on labels]
Reported-by: syzbot+5e01f56d1c53ac3749fb@syzkaller.appspotmail.com
First crash: 12d, last: 12d
▶ ▼ Duplicate bugs (3)
duplicates (3):
Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
possible deadlock in ext4_truncate ext4 3 7d05h 14d 0/28 closed as dup on 2024/12/12 23:40
possible deadlock in ext4_map_blocks (2) ext4 5 3d17h 17d 0/28 closed as dup on 2024/12/12 23:41
possible deadlock in ext4_da_get_block_prep (2) ext4 3 2d15h 9d18h 0/28 closed as dup on 2024/12/12 23:40
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [xfs?] possible deadlock in xfs_vn_update_time 1 (2) 2024/12/12 23:19

Sample crash report:
XFS (loop8): Ending clean mount
======================================================
WARNING: possible circular locking dependency detected
6.13.0-rc1-syzkaller-00378-g62b5a46999c7 #0 Not tainted
------------------------------------------------------
syz.8.1897/11319 is trying to acquire lock:
ffff88807ab0a610 (sb_internal#3){.+.+}-{0:0}, at: xfs_vn_update_time+0x1e9/0x5e0 fs/xfs/xfs_iops.c:1103

but task is already holding lock:
ffff8880347a1560 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:122 [inline]
ffff8880347a1560 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x160/0x360 mm/util.c:578

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #5 (&mm->mmap_lock){++++}-{4:4}:
       __might_fault mm/memory.c:6751 [inline]
       __might_fault+0x11b/0x190 mm/memory.c:6744
       _inline_copy_from_user include/linux/uaccess.h:162 [inline]
       _copy_from_user+0x29/0xd0 lib/usercopy.c:18
       copy_from_user include/linux/uaccess.h:212 [inline]
       __blk_trace_setup+0xa8/0x180 kernel/trace/blktrace.c:626
       blk_trace_ioctl+0x163/0x290 kernel/trace/blktrace.c:740
       blkdev_ioctl+0x109/0x6d0 block/ioctl.c:682
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:906 [inline]
       __se_sys_ioctl fs/ioctl.c:892 [inline]
       __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:892
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #4 (&q->debugfs_mutex){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735
       blk_mq_init_sched+0x42b/0x640 block/blk-mq-sched.c:473
       elevator_init_mq+0x2cd/0x420 block/elevator.c:610
       add_disk_fwnode+0x113/0x1300 block/genhd.c:413
       sd_probe+0xa86/0x1000 drivers/scsi/sd.c:4024
       call_driver_probe drivers/base/dd.c:579 [inline]
       really_probe+0x241/0xa90 drivers/base/dd.c:658
       __driver_probe_device+0x1de/0x440 drivers/base/dd.c:800
       driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830
       __device_attach_driver+0x1df/0x310 drivers/base/dd.c:958
       bus_for_each_drv+0x15a/0x1e0 drivers/base/bus.c:459
       __device_attach_async_helper+0x1d3/0x290 drivers/base/dd.c:987
       async_run_entry_fn+0x9f/0x530 kernel/async.c:129
       process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
       process_scheduled_works kernel/workqueue.c:3310 [inline]
       worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
       kthread+0x2c4/0x3a0 kernel/kthread.c:389
       ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

-> #3 (&q->q_usage_counter(queue)#50){++++}-{0:0}:
       blk_queue_enter+0x50f/0x640 block/blk-core.c:328
       blk_mq_alloc_request+0x59b/0x950 block/blk-mq.c:652
       scsi_alloc_request drivers/scsi/scsi_lib.c:1222 [inline]
       scsi_execute_cmd+0x1eb/0xf40 drivers/scsi/scsi_lib.c:304
       read_capacity_16+0x213/0xe10 drivers/scsi/sd.c:2655
       sd_read_capacity drivers/scsi/sd.c:2824 [inline]
       sd_revalidate_disk.isra.0+0x1a06/0xa8d0 drivers/scsi/sd.c:3734
       sd_probe+0x904/0x1000 drivers/scsi/sd.c:4010
       call_driver_probe drivers/base/dd.c:579 [inline]
       really_probe+0x241/0xa90 drivers/base/dd.c:658
       __driver_probe_device+0x1de/0x440 drivers/base/dd.c:800
       driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830
       __device_attach_driver+0x1df/0x310 drivers/base/dd.c:958
       bus_for_each_drv+0x15a/0x1e0 drivers/base/bus.c:459
       __device_attach_async_helper+0x1d3/0x290 drivers/base/dd.c:987
       async_run_entry_fn+0x9f/0x530 kernel/async.c:129
       process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
       process_scheduled_works kernel/workqueue.c:3310 [inline]
       worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
       kthread+0x2c4/0x3a0 kernel/kthread.c:389
       ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

-> #2 (&q->limits_lock){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735
       queue_limits_start_update include/linux/blkdev.h:949 [inline]
       loop_reconfigure_limits+0x407/0x8c0 drivers/block/loop.c:998
       loop_set_block_size drivers/block/loop.c:1473 [inline]
       lo_simple_ioctl drivers/block/loop.c:1496 [inline]
       lo_ioctl+0x901/0x18b0 drivers/block/loop.c:1559
       blkdev_ioctl+0x279/0x6d0 block/ioctl.c:693
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:906 [inline]
       __se_sys_ioctl fs/ioctl.c:892 [inline]
       __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:892
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&q->q_usage_counter(io)#23){++++}-{0:0}:
       bio_queue_enter block/blk.h:75 [inline]
       blk_mq_submit_bio+0x1fb6/0x24c0 block/blk-mq.c:3092
       __submit_bio+0x384/0x540 block/blk-core.c:629
       __submit_bio_noacct_mq block/blk-core.c:710 [inline]
       submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:739
       submit_bio_noacct+0x93a/0x1e20 block/blk-core.c:868
       xfs_buf_ioapply_map fs/xfs/xfs_buf.c:1586 [inline]
       _xfs_buf_ioapply+0x9f6/0xd70 fs/xfs/xfs_buf.c:1674
       __xfs_buf_submit+0x28b/0x820 fs/xfs/xfs_buf.c:1758
       xfs_buf_submit fs/xfs/xfs_buf.c:61 [inline]
       _xfs_buf_read fs/xfs/xfs_buf.c:809 [inline]
       xfs_buf_read_map+0x3fa/0xb70 fs/xfs/xfs_buf.c:873
       xfs_trans_read_buf_map+0x352/0x9a0 fs/xfs/xfs_trans_buf.c:304
       xfs_trans_read_buf fs/xfs/xfs_trans.h:213 [inline]
       xfs_read_agi+0x2a1/0x5c0 fs/xfs/libxfs/xfs_ialloc.c:2760
       xfs_ialloc_read_agi+0x10c/0x510 fs/xfs/libxfs/xfs_ialloc.c:2791
       xfs_dialloc_try_ag fs/xfs/libxfs/xfs_ialloc.c:1809 [inline]
       xfs_dialloc+0x898/0x1820 fs/xfs/libxfs/xfs_ialloc.c:1945
       xfs_qm_qino_alloc+0x2a7/0x7f0 fs/xfs/xfs_qm.c:996
       xfs_qm_init_quotainos+0x5f4/0x6c0 fs/xfs/xfs_qm.c:1845
       xfs_qm_init_quotainfo+0xf4/0xb20 fs/xfs/xfs_qm.c:824
       xfs_qm_mount_quotas+0x9c/0x6a0 fs/xfs/xfs_qm.c:1680
       xfs_mountfs+0x1ed1/0x2230 fs/xfs/xfs_mount.c:1030
       xfs_fs_fill_super+0x1557/0x1f50 fs/xfs/xfs_super.c:1791
       get_tree_bdev_flags+0x38e/0x620 fs/super.c:1636
       vfs_get_tree+0x92/0x380 fs/super.c:1814
       do_new_mount fs/namespace.c:3507 [inline]
       path_mount+0x14e6/0x1f20 fs/namespace.c:3834
       do_mount fs/namespace.c:3847 [inline]
       __do_sys_mount fs/namespace.c:4057 [inline]
       __se_sys_mount fs/namespace.c:4034 [inline]
       __x64_sys_mount+0x294/0x320 fs/namespace.c:4034
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (sb_internal#3){.+.+}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3161 [inline]
       check_prevs_add kernel/locking/lockdep.c:3280 [inline]
       validate_chain kernel/locking/lockdep.c:3904 [inline]
       __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
       lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1725 [inline]
       sb_start_intwrite include/linux/fs.h:1908 [inline]
       xfs_trans_alloc+0x4fa/0x940 fs/xfs/xfs_trans.c:266
       xfs_vn_update_time+0x1e9/0x5e0 fs/xfs/xfs_iops.c:1103
       inode_update_time fs/inode.c:2124 [inline]
       touch_atime+0x352/0x5d0 fs/inode.c:2197
       file_accessed include/linux/fs.h:2539 [inline]
       xfs_file_mmap+0x4ad/0x630 fs/xfs/xfs_file.c:1581
       call_mmap include/linux/fs.h:2183 [inline]
       mmap_file mm/internal.h:124 [inline]
       __mmap_new_file_vma mm/vma.c:2291 [inline]
       __mmap_new_vma mm/vma.c:2355 [inline]
       __mmap_region+0x1789/0x2670 mm/vma.c:2456
       mmap_region+0x270/0x320 mm/mmap.c:1347
       do_mmap+0xc00/0xfc0 mm/mmap.c:496
       vm_mmap_pgoff+0x1ba/0x360 mm/util.c:580
       ksys_mmap_pgoff+0x32c/0x5c0 mm/mmap.c:542
       __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
       __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
       __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  sb_internal#3 --> &q->debugfs_mutex --> &mm->mmap_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&mm->mmap_lock);
                               lock(&q->debugfs_mutex);
                               lock(&mm->mmap_lock);
  rlock(sb_internal#3);

 *** DEADLOCK ***

2 locks held by syz.8.1897/11319:
 #0: ffff8880347a1560 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:122 [inline]
 #0: ffff8880347a1560 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x160/0x360 mm/util.c:578
 #1: ffff88807ab0a420 (sb_writers#23){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2539 [inline]
 #1: ffff88807ab0a420 (sb_writers#23){.+.+}-{0:0}, at: xfs_file_mmap+0x4ad/0x630 fs/xfs/xfs_file.c:1581

stack backtrace:
CPU: 0 UID: 0 PID: 11319 Comm: syz.8.1897 Not tainted 6.13.0-rc1-syzkaller-00378-g62b5a46999c7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_circular_bug+0x419/0x5d0 kernel/locking/lockdep.c:2074
 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2206
 check_prev_add kernel/locking/lockdep.c:3161 [inline]
 check_prevs_add kernel/locking/lockdep.c:3280 [inline]
 validate_chain kernel/locking/lockdep.c:3904 [inline]
 __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
 percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
 __sb_start_write include/linux/fs.h:1725 [inline]
 sb_start_intwrite include/linux/fs.h:1908 [inline]
 xfs_trans_alloc+0x4fa/0x940 fs/xfs/xfs_trans.c:266
 xfs_vn_update_time+0x1e9/0x5e0 fs/xfs/xfs_iops.c:1103
 inode_update_time fs/inode.c:2124 [inline]
 touch_atime+0x352/0x5d0 fs/inode.c:2197
 file_accessed include/linux/fs.h:2539 [inline]
 xfs_file_mmap+0x4ad/0x630 fs/xfs/xfs_file.c:1581
 call_mmap include/linux/fs.h:2183 [inline]
 mmap_file mm/internal.h:124 [inline]
 __mmap_new_file_vma mm/vma.c:2291 [inline]
 __mmap_new_vma mm/vma.c:2355 [inline]
 __mmap_region+0x1789/0x2670 mm/vma.c:2456
 mmap_region+0x270/0x320 mm/mmap.c:1347
 do_mmap+0xc00/0xfc0 mm/mmap.c:496
 vm_mmap_pgoff+0x1ba/0x360 mm/util.c:580
 ksys_mmap_pgoff+0x32c/0x5c0 mm/mmap.c:542
 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
 __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
 __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7eff20f7fed9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007eff1edf6058 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007eff21145fa0 RCX: 00007eff20f7fed9
RDX: 0000000000000002 RSI: 0000000000b36000 RDI: 0000000020000000
RBP: 00007eff20ff3cc8 R08: 0000000000000004 R09: 0000000000000000
R10: 0000000000028011 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007eff21145fa0 R15: 00007ffe670abff8
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/08 22:32 upstream 62b5a46999c7 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root possible deadlock in xfs_vn_update_time
* Struck through repros no longer work on HEAD.