I got the below kasan splat running on 6.2-rc3.
The machine is currently running some SMR & CMR drives benchmarks and xfs is
used only for the rootfs (on an m.2 ssd) to log test results. So nothing special
really exercising xfs.
My tests are still running (they take several days so I do not want to interrupt
them) so I have not tried the latest Linus tree. Have you got reports of
something similar ? Is that fixed already ? I did not dig into the issue :)
======================================================
WARNING: possible circular locking dependency detected
6.2.0-rc3+ #1637 Not tainted
------------------------------------------------------
kswapd0/177 is trying to acquire lock:
ffff8881fe452118 (&xfs_dir_ilock_class){++++}-{3:3}, at:
xfs_icwalk_ag+0x9d8/0x11f0 [xfs]
but task is already holding lock:
ffffffff83b5d280 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x760/0xf90
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (fs_reclaim){+.+.}-{0:0}:
fs_reclaim_acquire+0x122/0x170
__alloc_pages+0x1b3/0x690
__stack_depot_save+0x3b4/0x4b0
kasan_save_stack+0x32/0x40
kasan_set_track+0x25/0x30
__kasan_kmalloc+0x88/0x90
__kmalloc_node+0x5a/0xc0
xfs_attr_copy_value+0xf2/0x170 [xfs]
xfs_attr_get+0x36a/0x4b0 [xfs]
xfs_get_acl+0x1a5/0x3f0 [xfs]
__get_acl.part.0+0x1d5/0x2e0
vfs_get_acl+0x11b/0x1a0
do_get_acl+0x39/0x520
do_getxattr+0xcb/0x330
getxattr+0xde/0x140
path_getxattr+0xc1/0x140
do_syscall_64+0x38/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
-> #0 (&xfs_dir_ilock_class){++++}-{3:3}:
__lock_acquire+0x2b91/0x69e0
lock_acquire+0x1a3/0x520
down_write_nested+0x9c/0x240
xfs_icwalk_ag+0x9d8/0x11f0 [xfs]
xfs_icwalk+0x4c/0xd0 [xfs]
xfs_reclaim_inodes_nr+0x148/0x1f0 [xfs]
super_cache_scan+0x3a5/0x500
do_shrink_slab+0x324/0x900
shrink_slab+0x376/0x4f0
shrink_node+0x80f/0x1ae0
balance_pgdat+0x6e2/0xf90
kswapd+0x312/0x9b0
kthread+0x29f/0x340
ret_from_fork+0x1f/0x30
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(fs_reclaim);
lock(&xfs_dir_ilock_class);
lock(fs_reclaim);
lock(&xfs_dir_ilock_class);
*** DEADLOCK ***
3 locks held by kswapd0/177:
#0: ffffffff83b5d280 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x760/0xf90
#1: ffffffff83b2b8b0 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0x237/0x4f0
#2: ffff8881a73cc0e0 (&type->s_umount_key#36){++++}-{3:3}, at:
super_cache_scan+0x58/0x500
stack backtrace:
CPU: 16 PID: 177 Comm: kswapd0 Not tainted 6.2.0-rc3+ #1637
Hardware name: Supermicro AS -2014CS-TR/H12SSW-AN6, BIOS 2.4 02/23/2022
Call Trace:
<TASK>
dump_stack_lvl+0x50/0x63
check_noncircular+0x268/0x310
? print_circular_bug+0x440/0x440
? check_path.constprop.0+0x24/0x50
? save_trace+0x46/0xd00
? add_lock_to_list+0x188/0x5a0
__lock_acquire+0x2b91/0x69e0
? lockdep_hardirqs_on_prepare+0x410/0x410
lock_acquire+0x1a3/0x520
? xfs_icwalk_ag+0x9d8/0x11f0 [xfs]
? lock_downgrade+0x6d0/0x6d0
? lock_is_held_type+0xdc/0x130
down_write_nested+0x9c/0x240
? xfs_icwalk_ag+0x9d8/0x11f0 [xfs]
? up_read+0x30/0x30
? xfs_icwalk_ag+0x9d8/0x11f0 [xfs]
? rcu_read_lock_sched_held+0x3f/0x70
? xfs_ilock+0x252/0x2f0 [xfs]
xfs_icwalk_ag+0x9d8/0x11f0 [xfs]
? xfs_inode_free_cowblocks+0x1f0/0x1f0 [xfs]
? lock_is_held_type+0xdc/0x130
? find_held_lock+0x2d/0x110
? xfs_perag_get+0x2c0/0x2c0 [xfs]
? rwlock_bug.part.0+0x90/0x90
xfs_icwalk+0x4c/0xd0 [xfs]
xfs_reclaim_inodes_nr+0x148/0x1f0 [xfs]
? xfs_reclaim_inodes+0x1f0/0x1f0 [xfs]
super_cache_scan+0x3a5/0x500
do_shrink_slab+0x324/0x900
shrink_slab+0x376/0x4f0
? set_shrinker_bit+0x230/0x230
? mem_cgroup_calculate_protection+0x4a/0x4e0
shrink_node+0x80f/0x1ae0
balance_pgdat+0x6e2/0xf90
? finish_task_switch.isra.0+0x218/0x920
? shrink_node+0x1ae0/0x1ae0
? lock_is_held_type+0xdc/0x130
kswapd+0x312/0x9b0
? balance_pgdat+0xf90/0xf90
? prepare_to_swait_exclusive+0x250/0x250
? __kthread_parkme+0xc1/0x1f0
? schedule+0x151/0x230
? balance_pgdat+0xf90/0xf90
kthread+0x29f/0x340
? kthread_complete_and_exit+0x30/0x30
ret_from_fork+0x1f/0x30
</TASK>
--
Damien Le Moal
Western Digital Research
