====================================================== WARNING: possible circular locking dependency detected 6.11.0-rc3-syzkaller-00156-gd7a5aa4b3c00 #0 Not tainted ------------------------------------------------------ kswapd0/80 is trying to acquire lock: ffff88803af3e7d8 (&xfs_nondir_ilock_class#3){++++}-{3:3}, at: xfs_reclaim_inode fs/xfs/xfs_icache.c:944 [inline] ffff88803af3e7d8 (&xfs_nondir_ilock_class#3){++++}-{3:3}, at: xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1630 [inline] ffff88803af3e7d8 (&xfs_nondir_ilock_class#3){++++}-{3:3}, at: xfs_icwalk_ag+0x120e/0x1ad0 fs/xfs/xfs_icache.c:1712 but task is already holding lock: ffffffff8ea2fce0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6841 [inline] ffffffff8ea2fce0 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbb4/0x35a0 mm/vmscan.c:7223 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:3823 [inline] fs_reclaim_acquire+0x88/0x140 mm/page_alloc.c:3837 might_alloc include/linux/sched/mm.h:334 [inline] slab_pre_alloc_hook mm/slub.c:3939 [inline] slab_alloc_node mm/slub.c:4017 [inline] __do_kmalloc_node mm/slub.c:4157 [inline] __kmalloc_noprof+0xa9/0x400 mm/slub.c:4170 kmalloc_noprof include/linux/slab.h:685 [inline] xfs_attr_shortform_list+0x753/0x1900 fs/xfs/xfs_attr_list.c:117 xfs_attr_list+0x1d0/0x270 fs/xfs/xfs_attr_list.c:595 xfs_vn_listxattr+0x1d2/0x2c0 fs/xfs/xfs_xattr.c:341 vfs_listxattr fs/xattr.c:493 [inline] listxattr+0x107/0x290 fs/xattr.c:841 path_listxattr fs/xattr.c:865 [inline] __do_sys_llistxattr fs/xattr.c:883 [inline] __se_sys_llistxattr fs/xattr.c:880 [inline] __x64_sys_llistxattr+0x170/0x230 fs/xattr.c:880 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 (&xfs_nondir_ilock_class#3){++++}-{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 down_write_nested+0xa2/0x220 kernel/locking/rwsem.c:1695 xfs_reclaim_inode fs/xfs/xfs_icache.c:944 [inline] xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1630 [inline] xfs_icwalk_ag+0x120e/0x1ad0 fs/xfs/xfs_icache.c:1712 xfs_icwalk fs/xfs/xfs_icache.c:1761 [inline] xfs_reclaim_inodes_nr+0x2d4/0x3e0 fs/xfs/xfs_icache.c:1010 super_cache_scan+0x40f/0x4b0 fs/super.c:227 do_shrink_slab+0x701/0x1160 mm/shrinker.c:435 shrink_slab+0x1093/0x14d0 mm/shrinker.c:662 shrink_one+0x43b/0x850 mm/vmscan.c:4815 shrink_many mm/vmscan.c:4876 [inline] lru_gen_shrink_node mm/vmscan.c:4954 [inline] shrink_node+0x3799/0x3de0 mm/vmscan.c:5934 kswapd_shrink_node mm/vmscan.c:6762 [inline] balance_pgdat mm/vmscan.c:6954 [inline] kswapd+0x1bcd/0x35a0 mm/vmscan.c:7223 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(&xfs_nondir_ilock_class#3); lock(fs_reclaim); lock(&xfs_nondir_ilock_class#3); *** DEADLOCK *** 2 locks held by kswapd0/80: #0: ffffffff8ea2fce0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6841 [inline] #0: ffffffff8ea2fce0 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbb4/0x35a0 mm/vmscan.c:7223 #1: ffff888012a100e0 (&type->s_umount_key#44){.+.+}-{3:3}, at: super_trylock_shared fs/super.c:562 [inline] #1: ffff888012a100e0 (&type->s_umount_key#44){.+.+}-{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-rc3-syzkaller-00156-gd7a5aa4b3c00 #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: __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 down_write_nested+0xa2/0x220 kernel/locking/rwsem.c:1695 xfs_reclaim_inode fs/xfs/xfs_icache.c:944 [inline] xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1630 [inline] xfs_icwalk_ag+0x120e/0x1ad0 fs/xfs/xfs_icache.c:1712 xfs_icwalk fs/xfs/xfs_icache.c:1761 [inline] xfs_reclaim_inodes_nr+0x2d4/0x3e0 fs/xfs/xfs_icache.c:1010 super_cache_scan+0x40f/0x4b0 fs/super.c:227 do_shrink_slab+0x701/0x1160 mm/shrinker.c:435 shrink_slab+0x1093/0x14d0 mm/shrinker.c:662 shrink_one+0x43b/0x850 mm/vmscan.c:4815 shrink_many mm/vmscan.c:4876 [inline] lru_gen_shrink_node mm/vmscan.c:4954 [inline] shrink_node+0x3799/0x3de0 mm/vmscan.c:5934 kswapd_shrink_node mm/vmscan.c:6762 [inline] balance_pgdat mm/vmscan.c:6954 [inline] kswapd+0x1bcd/0x35a0 mm/vmscan.c:7223 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