======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.8.2398/14830 is trying to acquire lock:
ffffffff8ce648e8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1c0/0x490 block/bdev.c:527
but task is already holding lock:
ffff8880202842c0 (mapping.invalidate_lock){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:849 [inline]
ffff8880202842c0 (mapping.invalidate_lock){++++}-{3:3}, at: blkdev_fallocate+0x22b/0x6a0 block/fops.c:789
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #4 (mapping.invalidate_lock){++++}-{3:3}:
down_write+0x97/0x200 kernel/locking/rwsem.c:1573
filemap_invalidate_lock include/linux/fs.h:849 [inline]
set_blocksize+0x247/0x4b0 block/bdev.c:161
sb_set_blocksize block/bdev.c:178 [inline]
sb_min_blocksize+0xbe/0x190 block/bdev.c:194
ext4_load_super fs/ext4/super.c:5044 [inline]
__ext4_fill_super fs/ext4/super.c:5265 [inline]
ext4_fill_super+0x6f0/0x6790 fs/ext4/super.c:5740
get_tree_bdev+0x3f3/0x520 fs/super.c:1591
vfs_get_tree+0x8c/0x280 fs/super.c:1764
do_new_mount+0x24b/0xa40 fs/namespace.c:3386
init_mount+0xde/0x130 fs/init.c:25
do_mount_root+0x97/0x230 init/do_mounts.c:166
mount_root_generic+0x1a6/0x3e0 init/do_mounts.c:205
prepare_namespace+0xc2/0x100 init/do_mounts.c:489
kernel_init_freeable+0x42e/0x580 init/main.c:1578
kernel_init+0x1d/0x1c0 init/main.c:1455
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
-> #3 (&sb->s_type->i_mutex_key#8){++++}-{3:3}:
down_write+0x97/0x200 kernel/locking/rwsem.c:1573
inode_lock include/linux/fs.h:804 [inline]
set_blocksize+0x1ff/0x4b0 block/bdev.c:160
sb_set_blocksize block/bdev.c:178 [inline]
sb_min_blocksize+0xbe/0x190 block/bdev.c:194
ext4_load_super fs/ext4/super.c:5044 [inline]
__ext4_fill_super fs/ext4/super.c:5265 [inline]
ext4_fill_super+0x6f0/0x6790 fs/ext4/super.c:5740
get_tree_bdev+0x3f3/0x520 fs/super.c:1591
vfs_get_tree+0x8c/0x280 fs/super.c:1764
do_new_mount+0x24b/0xa40 fs/namespace.c:3386
init_mount+0xde/0x130 fs/init.c:25
do_mount_root+0x97/0x230 init/do_mounts.c:166
mount_root_generic+0x1a6/0x3e0 init/do_mounts.c:205
prepare_namespace+0xc2/0x100 init/do_mounts.c:489
kernel_init_freeable+0x42e/0x580 init/main.c:1578
kernel_init+0x1d/0x1c0 init/main.c:1455
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
-> #2 (&type->s_umount_key#32){++++}-{3:3}:
down_read+0x46/0x2e0 kernel/locking/rwsem.c:1520
__super_lock fs/super.c:58 [inline]
super_lock+0x17f/0x3a0 fs/super.c:117
super_lock_shared fs/super.c:146 [inline]
super_lock_shared_active fs/super.c:1442 [inline]
fs_bdev_mark_dead+0xad/0x1f0 fs/super.c:1458
bdev_mark_dead+0x83/0x1a0 block/bdev.c:1030
disk_force_media_change+0x14e/0x1d0 block/disk-events.c:302
__loop_clr_fd+0x396/0x660 drivers/block/loop.c:1170
loop_clr_fd drivers/block/loop.c:1253 [inline]
lo_ioctl+0x14a4/0x1d20 drivers/block/loop.c:1578
blkdev_ioctl+0x5b2/0x730 block/ioctl.c:639
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> #1 (&bdev->bd_holder_lock){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x136/0xcc0 kernel/locking/mutex.c:747
bd_finish_claiming+0x22f/0x3f0 block/bdev.c:585
blkdev_get_by_dev+0x45c/0x600 block/bdev.c:818
bdev_open_by_dev+0x77/0x100 block/bdev.c:859
setup_bdev_super+0x59/0x660 fs/super.c:1496
mount_bdev+0x1d3/0x2d0 fs/super.c:1640
legacy_get_tree+0xea/0x180 fs/fs_context.c:662
vfs_get_tree+0x8c/0x280 fs/super.c:1764
do_new_mount+0x24b/0xa40 fs/namespace.c:3386
init_mount+0xde/0x130 fs/init.c:25
do_mount_root+0x97/0x230 init/do_mounts.c:166
mount_root_generic+0x1a6/0x3e0 init/do_mounts.c:205
prepare_namespace+0xc2/0x100 init/do_mounts.c:489
kernel_init_freeable+0x42e/0x580 init/main.c:1578
kernel_init+0x1d/0x1c0 init/main.c:1455
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
-> #0 (bdev_lock){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2df1/0x7d40 kernel/locking/lockdep.c:5137
lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x136/0xcc0 kernel/locking/mutex.c:747
bd_prepare_to_claim+0x1c0/0x490 block/bdev.c:527
truncate_bdev_range+0x4e/0x260 block/bdev.c:105
blkdev_fallocate+0x50d/0x6a0 block/fops.c:798
vfs_fallocate+0x58e/0x700 fs/open.c:324
ksys_fallocate fs/open.c:347 [inline]
__do_sys_fallocate fs/open.c:355 [inline]
__se_sys_fallocate fs/open.c:353 [inline]
__x64_sys_fallocate+0xc1/0x110 fs/open.c:353
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
other info that might help us debug this:
Chain exists of:
bdev_lock --> &sb->s_type->i_mutex_key#8 --> mapping.invalidate_lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(mapping.invalidate_lock);
lock(&sb->s_type->i_mutex_key#8);
lock(mapping.invalidate_lock);
lock(bdev_lock);
*** DEADLOCK ***
2 locks held by syz.8.2398/14830:
#0: ffff888020284130 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#0: ffff888020284130 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: blkdev_fallocate+0x205/0x6a0 block/fops.c:788
#1: ffff8880202842c0 (mapping.invalidate_lock){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:849 [inline]
#1: ffff8880202842c0 (mapping.invalidate_lock){++++}-{3:3}, at: blkdev_fallocate+0x22b/0x6a0 block/fops.c:789
stack backtrace:
CPU: 0 PID: 14830 Comm: syz.8.2398 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
check_noncircular+0x2fc/0x400 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2df1/0x7d40 kernel/locking/lockdep.c:5137
lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x136/0xcc0 kernel/locking/mutex.c:747
bd_prepare_to_claim+0x1c0/0x490 block/bdev.c:527
truncate_bdev_range+0x4e/0x260 block/bdev.c:105
blkdev_fallocate+0x50d/0x6a0 block/fops.c:798
vfs_fallocate+0x58e/0x700 fs/open.c:324
ksys_fallocate fs/open.c:347 [inline]
__do_sys_fallocate fs/open.c:355 [inline]
__se_sys_fallocate fs/open.c:353 [inline]
__x64_sys_fallocate+0xc1/0x110 fs/open.c:353
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6219d9c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f621ad20028 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f621a016090 RCX: 00007f6219d9c819
RDX: 0000000000000000 RSI: 0000000000000011 RDI: 0000000000000003
RBP: 00007f621ad20090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000005345 R11: 0000000000000246 R12: 0000000000000001
R13: 00007f621a016128 R14: 00007f621a016090 R15: 00007ffc285397d8
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 0 PID: 14830 Comm: syz.8.2398 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
fail_dump lib/fault-inject.c:52 [inline]
should_fail_ex+0x39d/0x4d0 lib/fault-inject.c:153
should_failslab+0x9/0x20 mm/slab_common.c:1500
slab_pre_alloc_hook+0x59/0x310 mm/slab.h:716
slab_alloc_node mm/slub.c:3477 [inline]
__kmem_cache_alloc_node+0x53/0x250 mm/slub.c:3534
kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098
kmalloc include/linux/slab.h:600 [inline]
kzalloc include/linux/slab.h:721 [inline]
task_numa_work+0x92d/0x1360 kernel/sched/fair.c:3375
task_work_run+0x1d4/0x260 kernel/task_work.c:245
get_signal+0x1235/0x13f0 kernel/signal.c:2678
arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6219d9c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f621ad20028 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffff RBX: 00007f621a016090 RCX: 00007f6219d9c819
RDX: 0000000000000000 RSI: 0000000000000011 RDI: 0000000000000003
RBP: 00007f621ad20090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000005345 R11: 0000000000000246 R12: 0000000000000001
R13: 00007f621a016128 R14: 00007f621a016090 R15: 00007ffc285397d8