EXT4-fs (loop1): shut down requested (0) ====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc3-next-20250623-syzkaller #0 Not tainted ------------------------------------------------------ syz.1.1960/11168 is trying to acquire lock: ffff88804f672618 (sb_internal){++++}-{0:0}, at: sb_wait_write fs/super.c:1900 [inline] ffff88804f672618 (sb_internal){++++}-{0:0}, at: freeze_super+0x8b7/0x1130 fs/super.c:2183 but task is already holding lock: ffff88804f672520 (sb_pagefaults){++++}-{0:0}, at: sb_wait_write fs/super.c:1900 [inline] ffff88804f672520 (sb_pagefaults){++++}-{0:0}, at: freeze_super+0x50a/0x1130 fs/super.c:2169 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (sb_pagefaults){++++}-{0:0}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 percpu_down_read_internal+0x48/0x1c0 include/linux/percpu-rwsem.h:53 percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs.h:1798 [inline] sb_start_pagefault include/linux/fs.h:1963 [inline] ext4_page_mkwrite+0x1e3/0x1110 fs/ext4/inode.c:6576 do_page_mkwrite+0x14d/0x310 mm/memory.c:3396 do_shared_fault mm/memory.c:5684 [inline] do_fault mm/memory.c:5746 [inline] do_pte_missing mm/memory.c:4269 [inline] handle_pte_fault mm/memory.c:6087 [inline] __handle_mm_fault+0x1a60/0x5620 mm/memory.c:6230 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6399 do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1387 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #3 (&mm->mmap_lock){++++}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __might_fault+0xcc/0x130 mm/memory.c:6989 _inline_copy_to_user include/linux/uaccess.h:192 [inline] _copy_to_user+0x2c/0xb0 lib/usercopy.c:26 copy_to_user include/linux/uaccess.h:225 [inline] fiemap_fill_next_extent+0x1c0/0x390 fs/ioctl.c:145 ocfs2_fiemap+0x888/0xc90 fs/ocfs2/extent_map.c:806 ioctl_fiemap fs/ioctl.c:220 [inline] do_vfs_ioctl+0x16d3/0x1990 fs/ioctl.c:841 __do_sys_ioctl fs/ioctl.c:905 [inline] __se_sys_ioctl+0x82/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (&ocfs2_quota_ip_alloc_sem_key){++++}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1577 ocfs2_create_local_dquot+0x19d/0x1a40 fs/ocfs2/quota_local.c:1227 ocfs2_acquire_dquot+0x80f/0xb30 fs/ocfs2/quota_global.c:883 dqget+0x7ae/0xf10 fs/quota/dquot.c:977 __dquot_initialize+0x3b3/0xcb0 fs/quota/dquot.c:1505 ocfs2_get_init_inode+0x13b/0x1b0 fs/ocfs2/namei.c:202 ocfs2_mknod+0x863/0x2050 fs/ocfs2/namei.c:310 ocfs2_mkdir+0x191/0x440 fs/ocfs2/namei.c:656 vfs_mkdir+0x306/0x510 fs/namei.c:4366 do_mkdirat+0x247/0x590 fs/namei.c:4399 __do_sys_mkdir fs/namei.c:4421 [inline] __se_sys_mkdir fs/namei.c:4419 [inline] __x64_sys_mkdir+0x6c/0x80 fs/namei.c:4419 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&dquot->dq_lock){+.+.}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __mutex_lock_common kernel/locking/mutex.c:602 [inline] __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747 dquot_release+0x66/0x600 fs/quota/dquot.c:531 ext4_release_dquot+0x3ee/0x6c0 fs/ext4/ext4_jbd2.h:-1 quota_release_workfn+0x35c/0x610 fs/quota/dquot.c:840 process_one_work kernel/workqueue.c:3239 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #0 (sb_internal){++++}-{0:0}: check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 percpu_down_write+0x54/0x330 kernel/locking/percpu-rwsem.c:232 sb_wait_write fs/super.c:1900 [inline] freeze_super+0x8b7/0x1130 fs/super.c:2183 fs_bdev_freeze+0x1a3/0x310 fs/super.c:1529 bdev_freeze+0xd5/0x220 block/bdev.c:298 ext4_force_shutdown+0x322/0x560 fs/ext4/ioctl.c:822 ext4_ioctl_shutdown fs/ext4/ioctl.c:857 [inline] __ext4_ioctl fs/ext4/ioctl.c:1587 [inline] ext4_ioctl+0x1d39/0x3510 fs/ext4/ioctl.c:1626 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: sb_internal --> &mm->mmap_lock --> sb_pagefaults Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sb_pagefaults); lock(&mm->mmap_lock); lock(sb_pagefaults); lock(sb_internal); *** DEADLOCK *** 4 locks held by syz.1.1960/11168: #0: ffff888022e346b0 (&bdev->bd_fsfreeze_mutex){+.+.}-{4:4}, at: bdev_freeze+0x2a/0x220 block/bdev.c:289 #1: ffff88804f672428 (sb_writers#4){++++}-{0:0}, at: sb_wait_write fs/super.c:1900 [inline] #1: ffff88804f672428 (sb_writers#4){++++}-{0:0}, at: freeze_super+0x4db/0x1130 fs/super.c:2164 #2: ffff88804f6720e0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #2: ffff88804f6720e0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #2: ffff88804f6720e0 (&type->s_umount_key#32){++++}-{4:4}, at: freeze_super+0x4e3/0x1130 fs/super.c:2165 #3: ffff88804f672520 (sb_pagefaults){++++}-{0:0}, at: sb_wait_write fs/super.c:1900 [inline] #3: ffff88804f672520 (sb_pagefaults){++++}-{0:0}, at: freeze_super+0x50a/0x1130 fs/super.c:2169 stack backtrace: CPU: 1 UID: 0 PID: 11168 Comm: syz.1.1960 Not tainted 6.16.0-rc3-next-20250623-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2046 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 percpu_down_write+0x54/0x330 kernel/locking/percpu-rwsem.c:232 sb_wait_write fs/super.c:1900 [inline] freeze_super+0x8b7/0x1130 fs/super.c:2183 fs_bdev_freeze+0x1a3/0x310 fs/super.c:1529 bdev_freeze+0xd5/0x220 block/bdev.c:298 ext4_force_shutdown+0x322/0x560 fs/ext4/ioctl.c:822 ext4_ioctl_shutdown fs/ext4/ioctl.c:857 [inline] __ext4_ioctl fs/ext4/ioctl.c:1587 [inline] ext4_ioctl+0x1d39/0x3510 fs/ext4/ioctl.c:1626 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2a98f8e929 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:00007f2a99d6d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f2a991b5fa0 RCX: 00007f2a98f8e929 RDX: 0000200000000080 RSI: 000000008004587d RDI: 0000000000000004 RBP: 00007f2a99010b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f2a991b5fa0 R15: 00007fff3ffb9578