Forwarded: Re: [syzbot] [xfs?] inconsistent lock state in igrab

[syzbot <syzbot+5eb0d61dfb76ca12670c@syzkaller.appspotmail.com>]

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Subject: Re: [syzbot] [xfs?] inconsistent lock state in igrab
Author: djwong@kernel.org

#syz test git://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux.git f90fa6ef5701f63c5ed29d93b6d58a2fde30836d

On Sat, Feb 14, 2026 at 12:18:36AM -0800, syzbot wrote:
> syzbot has found a reproducer for the following issue on:
> 
> HEAD commit:    cd7a5651db26 alpha: add missing address argument in call t..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=13b47e5a580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=e600149b13c010eb
> dashboard link: https://syzkaller.appspot.com/bug?extid=5eb0d61dfb76ca12670c
> compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=15df8722580000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17f362aa580000
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/ea46ed04f19d/disk-cd7a5651.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/ee7aa4ba7700/vmlinux-cd7a5651.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/70280d10edbe/bzImage-cd7a5651.xz
> mounted in repro: https://storage.googleapis.com/syzbot-assets/41cb64e4f612/mount_0.gz
>   fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=1105a6e6580000)
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+5eb0d61dfb76ca12670c@syzkaller.appspotmail.com
> 
> I/O error, dev loop0, sector 512 op 0x0:(READ) flags 0x880700 phys_seg 1 prio class 2
> I/O error, dev loop0, sector 18692 op 0x0:(READ) flags 0x880700 phys_seg 1 prio class 2
> ================================
> WARNING: inconsistent lock state
> syzkaller #0 Not tainted
> --------------------------------
> inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
> ksoftirqd/0/15 [HC0[0]:SC1[1]:HE1:SE0] takes:
> ffff888059619180 (&sb->s_type->i_lock_key#36){+.?.}-{3:3}, at: spin_lock include/linux/spinlock.h:341 [inline]
> ffff888059619180 (&sb->s_type->i_lock_key#36){+.?.}-{3:3}, at: igrab+0x2a/0x230 fs/inode.c:1583
> {SOFTIRQ-ON-W} state was registered at:
>   lock_acquire kernel/locking/lockdep.c:5868 [inline]
>   lock_acquire+0x17c/0x330 kernel/locking/lockdep.c:5825
>   __raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline]
>   _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
>   spin_lock include/linux/spinlock.h:341 [inline]
>   unlock_new_inode+0x7a/0x330 fs/inode.c:1222
>   xfs_finish_inode_setup fs/xfs/xfs_inode.h:630 [inline]
>   xfs_setup_existing_inode fs/xfs/xfs_inode.h:637 [inline]
>   xfs_iget+0x1196/0x30f0 fs/xfs/xfs_icache.c:814
>   xfs_mountfs+0x108c/0x20b0 fs/xfs/xfs_mount.c:1072
>   xfs_fs_fill_super+0x153f/0x1f20 fs/xfs/xfs_super.c:1938
>   get_tree_bdev_flags+0x38c/0x620 fs/super.c:1694
>   vfs_get_tree+0x92/0x320 fs/super.c:1754
>   fc_mount fs/namespace.c:1193 [inline]
>   do_new_mount_fc fs/namespace.c:3760 [inline]
>   do_new_mount fs/namespace.c:3836 [inline]
>   path_mount+0x7d0/0x23d0 fs/namespace.c:4146
>   do_mount fs/namespace.c:4159 [inline]
>   __do_sys_mount fs/namespace.c:4348 [inline]
>   __se_sys_mount fs/namespace.c:4325 [inline]
>   __x64_sys_mount+0x293/0x310 fs/namespace.c:4325
>   do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
>   do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
>   entry_SYSCALL_64_after_hwframe+0x77/0x7f
> irq event stamp: 972992
> hardirqs last  enabled at (972992): [<ffffffff8b820072>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline]
> hardirqs last  enabled at (972992): [<ffffffff8b820072>] _raw_spin_unlock_irqrestore+0x52/0x80 kernel/locking/spinlock.c:194
> hardirqs last disabled at (972991): [<ffffffff8b81fd82>] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:130 [inline]
> hardirqs last disabled at (972991): [<ffffffff8b81fd82>] _raw_spin_lock_irqsave+0x52/0x60 kernel/locking/spinlock.c:162
> softirqs last  enabled at (972968): [<ffffffff81c7bb68>] run_ksoftirqd kernel/softirq.c:1063 [inline]
> softirqs last  enabled at (972968): [<ffffffff81c7bb68>] run_ksoftirqd+0x38/0x60 kernel/softirq.c:1055
> softirqs last disabled at (972973): [<ffffffff81c7bb68>] run_ksoftirqd kernel/softirq.c:1063 [inline]
> softirqs last disabled at (972973): [<ffffffff81c7bb68>] run_ksoftirqd+0x38/0x60 kernel/softirq.c:1055
> 
> other info that might help us debug this:
>  Possible unsafe locking scenario:
> 
>        CPU0
>        ----
>   lock(&sb->s_type->i_lock_key#36);
>   <Interrupt>
>     lock(&sb->s_type->i_lock_key#36);
> 
>  *** DEADLOCK ***
> 
> no locks held by ksoftirqd/0/15.
> 
> stack backtrace:
> CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Not tainted syzkaller #0 PREEMPT(full) 
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
> Call Trace:
>  <TASK>
>  __dump_stack lib/dump_stack.c:94 [inline]
>  dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
>  print_usage_bug.part.0+0x257/0x340 kernel/locking/lockdep.c:4042
>  print_usage_bug kernel/locking/lockdep.c:4010 [inline]
>  valid_state kernel/locking/lockdep.c:4056 [inline]
>  mark_lock_irq kernel/locking/lockdep.c:4267 [inline]
>  mark_lock+0x74a/0xa20 kernel/locking/lockdep.c:4753
>  mark_usage kernel/locking/lockdep.c:4642 [inline]
>  __lock_acquire+0x103a/0x2630 kernel/locking/lockdep.c:5191
>  lock_acquire kernel/locking/lockdep.c:5868 [inline]
>  lock_acquire+0x17c/0x330 kernel/locking/lockdep.c:5825
>  __raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline]
>  _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
>  spin_lock include/linux/spinlock.h:341 [inline]
>  igrab+0x2a/0x230 fs/inode.c:1583
>  fserror_report+0x3fd/0x750 fs/fserror.c:159
>  fserror_report_io include/linux/fserror.h:48 [inline]
>  iomap_finish_folio_read+0x168/0x2c0 fs/iomap/buffered-io.c:407
>  iomap_read_end_io+0x11a/0x430 fs/iomap/bio.c:17
>  bio_endio+0x755/0x8b0 block/bio.c:1790
>  blk_update_request+0x741/0x1330 block/blk-mq.c:1016
>  blk_mq_end_request+0x5b/0x420 block/blk-mq.c:1178
>  lo_complete_rq+0x1d4/0x2a0 drivers/block/loop.c:314
>  blk_complete_reqs+0xb1/0xf0 block/blk-mq.c:1253
>  handle_softirqs+0x1ea/0x910 kernel/softirq.c:622
>  run_ksoftirqd kernel/softirq.c:1063 [inline]
>  run_ksoftirqd+0x38/0x60 kernel/softirq.c:1055
>  smpboot_thread_fn+0x3d3/0xaa0 kernel/smpboot.c:160
>  kthread+0x370/0x450 kernel/kthread.c:467
>  ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
>  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
>  </TASK>
> 
> 
> ---
> If you want syzbot to run the reproducer, reply with:
> #syz test: git://repo/address.git branch-or-commit-hash
> If you attach or paste a git patch, syzbot will apply it before testing.
>