Hello, syzbot found the following issue on: HEAD commit: e5e038b7ae9d Merge tag 'fs_for_v6.9-rc1' of git://git.kern.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1629d9d1180000 kernel config: https://syzkaller.appspot.com/x/.config?x=6ce8d253b68e67fe dashboard link: https://syzkaller.appspot.com/bug?extid=8fdff861a781522bda4d compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-e5e038b7.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/82ab7eda09bc/vmlinux-e5e038b7.xz kernel image: https://storage.googleapis.com/syzbot-assets/bda17336e65d/bzImage-e5e038b7.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+8fdff861a781522bda4d@xxxxxxxxxxxxxxxxxxxxxxxxx ====================================================== WARNING: possible circular locking dependency detected 6.8.0-syzkaller-06619-ge5e038b7ae9d #0 Not tainted ------------------------------------------------------ syz-executor.0/10102 is trying to acquire lock: ffffffff8d92fb40 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:303 [inline] ffffffff8d92fb40 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:3746 [inline] ffffffff8d92fb40 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:3827 [inline] ffffffff8d92fb40 (fs_reclaim){+.+.}-{0:0}, at: kmem_cache_alloc+0x4f/0x320 mm/slub.c:3852 but task is already holding lock: ffff88802712c958 (&qinf->qi_tree_lock){+.+.}-{3:3}, at: xfs_qm_dqget_cache_insert.constprop.0+0x2a/0x2c0 fs/xfs/xfs_dquot.c:825 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&qinf->qi_tree_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 xfs_qm_dqfree_one+0x6f/0x1a0 fs/xfs/xfs_qm.c:1654 xfs_qm_shrink_scan+0x25c/0x3f0 fs/xfs/xfs_qm.c:531 do_shrink_slab+0x44f/0x1160 mm/shrinker.c:435 shrink_slab+0x18a/0x1310 mm/shrinker.c:662 shrink_one+0x493/0x7b0 mm/vmscan.c:4767 shrink_many mm/vmscan.c:4828 [inline] lru_gen_shrink_node mm/vmscan.c:4929 [inline] shrink_node+0x2191/0x3770 mm/vmscan.c:5888 kswapd_shrink_node mm/vmscan.c:6696 [inline] balance_pgdat+0x9d0/0x1a90 mm/vmscan.c:6886 kswapd+0x5c1/0xc10 mm/vmscan.c:7146 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 -> #0 (fs_reclaim){+.+.}-{0:0}: 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+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __fs_reclaim_acquire mm/page_alloc.c:3692 [inline] fs_reclaim_acquire+0x102/0x150 mm/page_alloc.c:3706 might_alloc include/linux/sched/mm.h:303 [inline] slab_pre_alloc_hook mm/slub.c:3746 [inline] slab_alloc_node mm/slub.c:3827 [inline] kmem_cache_alloc+0x4f/0x320 mm/slub.c:3852 radix_tree_node_alloc.constprop.0+0x7c/0x350 lib/radix-tree.c:276 radix_tree_extend+0x1a2/0x4d0 lib/radix-tree.c:425 __radix_tree_create lib/radix-tree.c:613 [inline] radix_tree_insert+0x499/0x630 lib/radix-tree.c:712 xfs_qm_dqget_cache_insert.constprop.0+0x38/0x2c0 fs/xfs/xfs_dquot.c:826 xfs_qm_dqget+0x182/0x4a0 fs/xfs/xfs_dquot.c:901 xfs_qm_vop_dqalloc+0x49a/0xe10 fs/xfs/xfs_qm.c:1755 xfs_create+0x422/0x1140 fs/xfs/xfs_inode.c:1041 xfs_generic_create+0x631/0x7c0 fs/xfs/xfs_iops.c:199 lookup_open.isra.0+0x10a1/0x13c0 fs/namei.c:3497 open_last_lookups fs/namei.c:3566 [inline] path_openat+0x92f/0x2990 fs/namei.c:3796 do_filp_open+0x1dc/0x430 fs/namei.c:3826 do_sys_openat2+0x17a/0x1e0 fs/open.c:1406 do_sys_open fs/open.c:1421 [inline] __do_compat_sys_openat fs/open.c:1481 [inline] __se_compat_sys_openat fs/open.c:1479 [inline] __ia32_compat_sys_openat+0x16e/0x210 fs/open.c:1479 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x7a/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&qinf->qi_tree_lock); lock(fs_reclaim); lock(&qinf->qi_tree_lock); lock(fs_reclaim); *** DEADLOCK *** 3 locks held by syz-executor.0/10102: #0: ffff88801e4f0420 (sb_writers#21){.+.+}-{0:0}, at: open_last_lookups fs/namei.c:3555 [inline] #0: ffff88801e4f0420 (sb_writers#21){.+.+}-{0:0}, at: path_openat+0x19a7/0x2990 fs/namei.c:3796 #1: ffff88804c060338 (&inode->i_sb->s_type->i_mutex_dir_key){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:793 [inline] #1: ffff88804c060338 (&inode->i_sb->s_type->i_mutex_dir_key){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3563 [inline] #1: ffff88804c060338 (&inode->i_sb->s_type->i_mutex_dir_key){+.+.}-{3:3}, at: path_openat+0x8c7/0x2990 fs/namei.c:3796 #2: ffff88802712c958 (&qinf->qi_tree_lock){+.+.}-{3:3}, at: xfs_qm_dqget_cache_insert.constprop.0+0x2a/0x2c0 fs/xfs/xfs_dquot.c:825 stack backtrace: CPU: 3 PID: 10102 Comm: syz-executor.0 Not tainted 6.8.0-syzkaller-06619-ge5e038b7ae9d #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 check_noncircular+0x31a/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+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __fs_reclaim_acquire mm/page_alloc.c:3692 [inline] fs_reclaim_acquire+0x102/0x150 mm/page_alloc.c:3706 might_alloc include/linux/sched/mm.h:303 [inline] slab_pre_alloc_hook mm/slub.c:3746 [inline] slab_alloc_node mm/slub.c:3827 [inline] kmem_cache_alloc+0x4f/0x320 mm/slub.c:3852 radix_tree_node_alloc.constprop.0+0x7c/0x350 lib/radix-tree.c:276 radix_tree_extend+0x1a2/0x4d0 lib/radix-tree.c:425 __radix_tree_create lib/radix-tree.c:613 [inline] radix_tree_insert+0x499/0x630 lib/radix-tree.c:712 xfs_qm_dqget_cache_insert.constprop.0+0x38/0x2c0 fs/xfs/xfs_dquot.c:826 xfs_qm_dqget+0x182/0x4a0 fs/xfs/xfs_dquot.c:901 xfs_qm_vop_dqalloc+0x49a/0xe10 fs/xfs/xfs_qm.c:1755 xfs_create+0x422/0x1140 fs/xfs/xfs_inode.c:1041 xfs_generic_create+0x631/0x7c0 fs/xfs/xfs_iops.c:199 lookup_open.isra.0+0x10a1/0x13c0 fs/namei.c:3497 open_last_lookups fs/namei.c:3566 [inline] path_openat+0x92f/0x2990 fs/namei.c:3796 do_filp_open+0x1dc/0x430 fs/namei.c:3826 do_sys_openat2+0x17a/0x1e0 fs/open.c:1406 do_sys_open fs/open.c:1421 [inline] __do_compat_sys_openat fs/open.c:1481 [inline] __se_compat_sys_openat fs/open.c:1479 [inline] __ia32_compat_sys_openat+0x16e/0x210 fs/open.c:1479 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x7a/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 RIP: 0023:0xf7328579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f5f225ac EFLAGS: 00000292 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 00000000200002c0 RDX: 000000000000275a RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> syz-executor.0 (10102) used greatest stack depth: 20032 bytes left ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
