EXT4-fs (loop0): stripe (5) is not aligned with cluster size (16), stripe is disabled EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.0.17/4917 is trying to acquire lock: ffff0000f046a230 (&ovl_i_mutex_key[depth]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] ffff0000f046a230 (&ovl_i_mutex_key[depth]){+.+.}-{4:4}, at: lock_two_nondirectories+0xc4/0x148 fs/inode.c:1254 but task is already holding lock: ffff0000dc4c0410 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write_file+0x64/0xdc fs/namespace.c:537 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (sb_writers#3){.+.+}-{0:0}: percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs/super.h:19 [inline] sb_start_write+0x5c/0x294 include/linux/fs/super.h:125 file_start_write include/linux/fs.h:2724 [inline] vfs_iter_write+0x190/0x4d0 fs/read_write.c:982 do_backing_file_write_iter fs/backing-file.c:226 [inline] backing_file_write_iter+0x450/0x6c8 fs/backing-file.c:274 ovl_write_iter+0x218/0x2c8 fs/overlayfs/file.c:370 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x52c/0xa14 fs/read_write.c:688 ksys_pwrite64+0x118/0x1b0 fs/read_write.c:795 __do_sys_pwrite64 fs/read_write.c:803 [inline] __se_sys_pwrite64 fs/read_write.c:800 [inline] __arm64_sys_pwrite64+0x9c/0xb4 fs/read_write.c:800 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594 -> #0 (&ovl_i_mutex_key[depth]){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x1780/0x2f44 kernel/locking/lockdep.c:5237 lock_acquire+0x140/0x368 kernel/locking/lockdep.c:5868 down_write+0x50/0xc0 kernel/locking/rwsem.c:1625 inode_lock include/linux/fs.h:1029 [inline] lock_two_nondirectories+0xc4/0x148 fs/inode.c:1254 ext4_move_extents+0x194/0x3580 fs/ext4/move_extent.c:589 __ext4_ioctl fs/ext4/ioctl.c:1657 [inline] ext4_ioctl+0x2a14/0x4234 fs/ext4/ioctl.c:1922 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __arm64_sys_ioctl+0x14c/0x1c4 fs/ioctl.c:583 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(sb_writers#3); lock(&ovl_i_mutex_key[depth]); lock(sb_writers#3); lock(&ovl_i_mutex_key[depth]); *** DEADLOCK *** 1 lock held by syz.0.17/4917: #0: ffff0000dc4c0410 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write_file+0x64/0xdc fs/namespace.c:537 stack backtrace: CPU: 1 UID: 0 PID: 4917 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 print_circular_bug+0x328/0x330 kernel/locking/lockdep.c:2043 check_noncircular+0x158/0x174 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x1780/0x2f44 kernel/locking/lockdep.c:5237 lock_acquire+0x140/0x368 kernel/locking/lockdep.c:5868 down_write+0x50/0xc0 kernel/locking/rwsem.c:1625 inode_lock include/linux/fs.h:1029 [inline] lock_two_nondirectories+0xc4/0x148 fs/inode.c:1254 ext4_move_extents+0x194/0x3580 fs/ext4/move_extent.c:589 __ext4_ioctl fs/ext4/ioctl.c:1657 [inline] ext4_ioctl+0x2a14/0x4234 fs/ext4/ioctl.c:1922 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __arm64_sys_ioctl+0x14c/0x1c4 fs/ioctl.c:583 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594