======================================================
WARNING: possible circular locking dependency detected
6.11.0-rc7-syzkaller-00039-g77f587896757 #0 Not tainted
------------------------------------------------------
kswapd0/80 is trying to acquire lock:
ffff888000297130 (&group->mark_mutex){+.+.}-{3:3}, at: fsnotify_group_lock include/linux/fsnotify_backend.h:270 [inline]
ffff888000297130 (&group->mark_mutex){+.+.}-{3:3}, at: fsnotify_destroy_mark+0x38/0x3c0 fs/notify/mark.c:578
but task is already holding lock:
ffffffff8ea2fde0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6821 [inline]
ffffffff8ea2fde0 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbf1/0x3720 mm/vmscan.c:7203
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (fs_reclaim){+.+.}-{0:0}:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
__fs_reclaim_acquire mm/page_alloc.c:3825 [inline]
fs_reclaim_acquire+0x88/0x140 mm/page_alloc.c:3839
might_alloc include/linux/sched/mm.h:334 [inline]
slab_pre_alloc_hook mm/slub.c:3943 [inline]
slab_alloc_node mm/slub.c:4021 [inline]
kmem_cache_alloc_noprof+0x3d/0x2a0 mm/slub.c:4048
inotify_new_watch fs/notify/inotify/inotify_user.c:599 [inline]
inotify_update_watch fs/notify/inotify/inotify_user.c:647 [inline]
__do_sys_inotify_add_watch fs/notify/inotify/inotify_user.c:786 [inline]
__se_sys_inotify_add_watch+0x72e/0x1070 fs/notify/inotify/inotify_user.c:729
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (&group->mark_mutex){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3133 [inline]
check_prevs_add kernel/locking/lockdep.c:3252 [inline]
validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
__lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
fsnotify_group_lock include/linux/fsnotify_backend.h:270 [inline]
fsnotify_destroy_mark+0x38/0x3c0 fs/notify/mark.c:578
fsnotify_destroy_marks+0x14a/0x660 fs/notify/mark.c:934
fsnotify_inoderemove include/linux/fsnotify.h:264 [inline]
dentry_unlink_inode+0x2e0/0x430 fs/dcache.c:408
__dentry_kill+0x20d/0x630 fs/dcache.c:615
shrink_kill+0xa9/0x2c0 fs/dcache.c:1060
shrink_dentry_list+0x2c0/0x5b0 fs/dcache.c:1087
prune_dcache_sb+0x10f/0x180 fs/dcache.c:1168
super_cache_scan+0x34f/0x4b0 fs/super.c:221
do_shrink_slab+0x701/0x1160 mm/shrinker.c:435
shrink_slab+0x1093/0x14d0 mm/shrinker.c:662
shrink_one+0x43b/0x850 mm/vmscan.c:4795
shrink_many mm/vmscan.c:4856 [inline]
lru_gen_shrink_node mm/vmscan.c:4934 [inline]
shrink_node+0x3799/0x3de0 mm/vmscan.c:5914
kswapd_shrink_node mm/vmscan.c:6742 [inline]
balance_pgdat mm/vmscan.c:6934 [inline]
kswapd+0x1cbc/0x3720 mm/vmscan.c:7203
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(fs_reclaim);
lock(&group->mark_mutex);
lock(fs_reclaim);
lock(&group->mark_mutex);
*** DEADLOCK ***
2 locks held by kswapd0/80:
#0: ffffffff8ea2fde0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6821 [inline]
#0: ffffffff8ea2fde0 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbf1/0x3720 mm/vmscan.c:7203
#1: ffff88800080c0e0 (&type->s_umount_key#47){.+.+}-{3:3}, at: super_trylock_shared fs/super.c:562 [inline]
#1: ffff88800080c0e0 (&type->s_umount_key#47){.+.+}-{3:3}, at: super_cache_scan+0x94/0x4b0 fs/super.c:196
stack backtrace:
CPU: 0 UID: 0 PID: 80 Comm: kswapd0 Not tainted 6.11.0-rc7-syzkaller-00039-g77f587896757 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:93 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2186
check_prev_add kernel/locking/lockdep.c:3133 [inline]
check_prevs_add kernel/locking/lockdep.c:3252 [inline]
validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
__lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
fsnotify_group_lock include/linux/fsnotify_backend.h:270 [inline]
fsnotify_destroy_mark+0x38/0x3c0 fs/notify/mark.c:578
fsnotify_destroy_marks+0x14a/0x660 fs/notify/mark.c:934
fsnotify_inoderemove include/linux/fsnotify.h:264 [inline]
dentry_unlink_inode+0x2e0/0x430 fs/dcache.c:408
__dentry_kill+0x20d/0x630 fs/dcache.c:615
shrink_kill+0xa9/0x2c0 fs/dcache.c:1060
shrink_dentry_list+0x2c0/0x5b0 fs/dcache.c:1087
prune_dcache_sb+0x10f/0x180 fs/dcache.c:1168
super_cache_scan+0x34f/0x4b0 fs/super.c:221
do_shrink_slab+0x701/0x1160 mm/shrinker.c:435
shrink_slab+0x1093/0x14d0 mm/shrinker.c:662
shrink_one+0x43b/0x850 mm/vmscan.c:4795
shrink_many mm/vmscan.c:4856 [inline]
lru_gen_shrink_node mm/vmscan.c:4934 [inline]
shrink_node+0x3799/0x3de0 mm/vmscan.c:5914
kswapd_shrink_node mm/vmscan.c:6742 [inline]
balance_pgdat mm/vmscan.c:6934 [inline]
kswapd+0x1cbc/0x3720 mm/vmscan.c:7203
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>