====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ kswapd0/78 is trying to acquire lock: ffff888012738920 (&(imap->im_aglock[index])){+.+.}-{4:4}, at: diFree+0x29f/0x2c40 fs/jfs/jfs_imap.c:889 but task is already holding lock: ffffffff8e0511c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6973 [inline] ffffffff8e0511c0 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0x92a/0x2820 mm/vmscan.c:7352 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (fs_reclaim){+.+.}-{0:0}: __fs_reclaim_acquire mm/page_alloc.c:4301 [inline] fs_reclaim_acquire+0x72/0x100 mm/page_alloc.c:4315 might_alloc include/linux/sched/mm.h:317 [inline] prepare_alloc_pages+0x152/0x650 mm/page_alloc.c:4978 __alloc_frozen_pages_noprof+0x123/0x370 mm/page_alloc.c:5199 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 ___kmalloc_large_node+0x4e/0x150 mm/slub.c:5593 __kmalloc_large_node_noprof+0x18/0x90 mm/slub.c:5624 __do_kmalloc_node mm/slub.c:5640 [inline] __kmalloc_noprof+0x4c9/0x800 mm/slub.c:5664 kmalloc_noprof include/linux/slab.h:961 [inline] ea_get+0x40f/0x1330 fs/jfs/xattr.c:489 __jfs_setxattr+0x57c/0x1120 fs/jfs/xattr.c:727 __jfs_xattr_set+0xda/0x170 fs/jfs/xattr.c:941 __vfs_setxattr+0x43c/0x480 fs/xattr.c:200 __vfs_setxattr_noperm+0x12d/0x660 fs/xattr.c:234 vfs_setxattr+0x16b/0x2f0 fs/xattr.c:321 do_setxattr fs/xattr.c:636 [inline] filename_setxattr+0x274/0x600 fs/xattr.c:665 path_setxattrat+0x364/0x3a0 fs/xattr.c:713 __do_sys_setxattr fs/xattr.c:747 [inline] __se_sys_setxattr fs/xattr.c:743 [inline] __x64_sys_setxattr+0xbc/0xe0 fs/xattr.c:743 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (&jfs_ip->xattr_sem){++++}-{4:4}: down_write+0x96/0x1f0 kernel/locking/rwsem.c:1590 __jfs_setxattr+0xe1/0x1120 fs/jfs/xattr.c:678 __jfs_xattr_set+0xda/0x170 fs/jfs/xattr.c:941 __vfs_setxattr+0x43c/0x480 fs/xattr.c:200 __vfs_setxattr_noperm+0x12d/0x660 fs/xattr.c:234 vfs_setxattr+0x16b/0x2f0 fs/xattr.c:321 do_setxattr fs/xattr.c:636 [inline] filename_setxattr+0x274/0x600 fs/xattr.c:665 path_setxattrat+0x364/0x3a0 fs/xattr.c:713 __do_sys_setxattr fs/xattr.c:747 [inline] __se_sys_setxattr fs/xattr.c:743 [inline] __x64_sys_setxattr+0xbc/0xe0 fs/xattr.c:743 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (&jfs_ip->commit_mutex){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776 diNewIAG fs/jfs/jfs_imap.c:2522 [inline] diAllocExt fs/jfs/jfs_imap.c:1905 [inline] diAllocAG+0x1478/0x1df0 fs/jfs/jfs_imap.c:1669 diAlloc+0x1d5/0x1680 fs/jfs/jfs_imap.c:1590 ialloc+0x8c/0x8f0 fs/jfs/jfs_inode.c:56 jfs_mkdir+0x193/0xa70 fs/jfs/namei.c:225 vfs_mkdir+0x512/0x5b0 fs/namei.c:5130 do_mkdirat+0x276/0x4b0 fs/namei.c:5164 __do_sys_mkdir fs/namei.c:5191 [inline] __se_sys_mkdir fs/namei.c:5189 [inline] __x64_sys_mkdir+0x6c/0x80 fs/namei.c:5189 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&jfs_ip->rdwrlock/1){++++}-{4:4}: down_read_nested+0x49/0x2e0 kernel/locking/rwsem.c:1662 diAlloc+0x795/0x1680 fs/jfs/jfs_imap.c:1388 ialloc+0x8c/0x8f0 fs/jfs/jfs_inode.c:56 jfs_create+0x18d/0xa80 fs/jfs/namei.c:92 lookup_open fs/namei.c:4440 [inline] open_last_lookups fs/namei.c:4540 [inline] path_openat+0x18bb/0x3dd0 fs/namei.c:4784 do_filp_open+0x1fa/0x410 fs/namei.c:4814 do_sys_openat2+0x121/0x200 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_creat fs/open.c:1514 [inline] __se_sys_creat fs/open.c:1508 [inline] __x64_sys_creat+0x8f/0xc0 fs/open.c:1508 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&(imap->im_aglock[index])){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x117/0x340 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776 diFree+0x29f/0x2c40 fs/jfs/jfs_imap.c:889 jfs_evict_inode+0x331/0x440 fs/jfs/inode.c:162 evict+0x5f4/0xae0 fs/inode.c:837 __dentry_kill+0x209/0x660 fs/dcache.c:670 shrink_kill+0xa9/0x2c0 fs/dcache.c:1137 shrink_dentry_list+0x2e0/0x5e0 fs/dcache.c:1164 prune_dcache_sb+0x10e/0x180 fs/dcache.c:1246 super_cache_scan+0x369/0x4b0 fs/super.c:222 do_shrink_slab+0x6df/0x10d0 mm/shrinker.c:437 shrink_slab_memcg mm/shrinker.c:550 [inline] shrink_slab+0x7ef/0x10d0 mm/shrinker.c:628 shrink_one+0x2d9/0x720 mm/vmscan.c:4919 shrink_many mm/vmscan.c:4980 [inline] lru_gen_shrink_node mm/vmscan.c:5058 [inline] shrink_node+0x2f7d/0x35b0 mm/vmscan.c:6045 kswapd_shrink_node mm/vmscan.c:6899 [inline] balance_pgdat mm/vmscan.c:7082 [inline] kswapd+0x145a/0x2820 mm/vmscan.c:7352 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 other info that might help us debug this: Chain exists of: &(imap->im_aglock[index]) --> &jfs_ip->xattr_sem --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&jfs_ip->xattr_sem); lock(fs_reclaim); lock(&(imap->im_aglock[index])); *** DEADLOCK *** 2 locks held by kswapd0/78: #0: ffffffff8e0511c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6973 [inline] #0: ffffffff8e0511c0 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0x92a/0x2820 mm/vmscan.c:7352 #1: ffff888011e160e0 (&type->s_umount_key#51){.+.+}-{4:4}, at: super_trylock_shared fs/super.c:563 [inline] #1: ffff888011e160e0 (&type->s_umount_key#51){.+.+}-{4:4}, at: super_cache_scan+0x91/0x4b0 fs/super.c:197 stack backtrace: CPU: 0 UID: 0 PID: 78 Comm: kswapd0 Not tainted syzkaller #0 PREEMPT(full) 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_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2043 check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x117/0x340 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776 diFree+0x29f/0x2c40 fs/jfs/jfs_imap.c:889 jfs_evict_inode+0x331/0x440 fs/jfs/inode.c:162 evict+0x5f4/0xae0 fs/inode.c:837 __dentry_kill+0x209/0x660 fs/dcache.c:670 shrink_kill+0xa9/0x2c0 fs/dcache.c:1137 shrink_dentry_list+0x2e0/0x5e0 fs/dcache.c:1164 prune_dcache_sb+0x10e/0x180 fs/dcache.c:1246 super_cache_scan+0x369/0x4b0 fs/super.c:222 do_shrink_slab+0x6df/0x10d0 mm/shrinker.c:437 shrink_slab_memcg mm/shrinker.c:550 [inline] shrink_slab+0x7ef/0x10d0 mm/shrinker.c:628 shrink_one+0x2d9/0x720 mm/vmscan.c:4919 shrink_many mm/vmscan.c:4980 [inline] lru_gen_shrink_node mm/vmscan.c:5058 [inline] shrink_node+0x2f7d/0x35b0 mm/vmscan.c:6045 kswapd_shrink_node mm/vmscan.c:6899 [inline] balance_pgdat mm/vmscan.c:7082 [inline] kswapd+0x145a/0x2820 mm/vmscan.c:7352 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246