Hello, syzbot found the following issue on: HEAD commit: 414c97c966b6 Add linux-next specific files for 20241119 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=167e5ac0580000 kernel config: https://syzkaller.appspot.com/x/.config?x=45719eec4c74e6ba dashboard link: https://syzkaller.appspot.com/bug?extid=aceb3ddca9f98c7c934f compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/394331d94392/disk-414c97c9.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/ad0dc40a5d80/vmlinux-414c97c9.xz kernel image: https://storage.googleapis.com/syzbot-assets/fccab23947ef/bzImage-414c97c9.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+aceb3ddca9f98c7c934f@xxxxxxxxxxxxxxxxxxxxxxxxx ====================================================== WARNING: possible circular locking dependency detected 6.12.0-next-20241119-syzkaller #0 Not tainted ------------------------------------------------------ kswapd0/88 is trying to acquire lock: ffff8881fb5e5958 (&qinf->qi_tree_lock){+.+.}-{4:4}, at: xfs_qm_dqfree_one+0x66/0x170 fs/xfs/xfs_qm.c:1874 but task is already holding lock: ffffffff8ea35ae0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6864 [inline] ffffffff8ea35ae0 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbf1/0x3700 mm/vmscan.c:7246 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (fs_reclaim){+.+.}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __fs_reclaim_acquire mm/page_alloc.c:3887 [inline] fs_reclaim_acquire+0x88/0x130 mm/page_alloc.c:3901 might_alloc include/linux/sched/mm.h:318 [inline] slab_pre_alloc_hook mm/slub.c:4055 [inline] slab_alloc_node mm/slub.c:4133 [inline] __kmalloc_cache_noprof+0x41/0x390 mm/slub.c:4309 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] kobject_uevent_env+0x28b/0x8e0 lib/kobject_uevent.c:540 loop_set_size drivers/block/loop.c:233 [inline] loop_set_status+0x5f0/0x8f0 drivers/block/loop.c:1285 lo_ioctl+0xcbc/0x1f50 blkdev_ioctl+0x57d/0x6a0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 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 -> #2 (&q->q_usage_counter(io)#20){++++}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 bio_queue_enter block/blk.h:75 [inline] blk_mq_submit_bio+0x1536/0x23a0 block/blk-mq.c:3092 __submit_bio+0x2c6/0x560 block/blk-core.c:629 __submit_bio_noacct_mq block/blk-core.c:710 [inline] submit_bio_noacct_nocheck+0x4d3/0xe30 block/blk-core.c:739 xlog_state_release_iclog+0x41d/0x7b0 fs/xfs/xfs_log.c:567 xlog_force_iclog fs/xfs/xfs_log.c:802 [inline] xlog_force_and_check_iclog fs/xfs/xfs_log.c:2866 [inline] xfs_log_force+0x616/0x960 fs/xfs/xfs_log.c:2943 xfs_qm_dqflush+0xd5e/0x15e0 fs/xfs/xfs_dquot.c:1333 xfs_qm_flush_one+0x129/0x430 fs/xfs/xfs_qm.c:1489 xfs_qm_dquot_walk+0x232/0x4a0 fs/xfs/xfs_qm.c:90 xfs_qm_quotacheck+0x3aa/0x6f0 fs/xfs/xfs_qm.c:1573 xfs_qm_mount_quotas+0x38f/0x680 fs/xfs/xfs_qm.c:1693 xfs_mountfs+0x1e60/0x2410 fs/xfs/xfs_mount.c:1030 xfs_fs_fill_super+0x12db/0x1590 fs/xfs/xfs_super.c:1791 get_tree_bdev_flags+0x48c/0x5c0 fs/super.c:1636 vfs_get_tree+0x90/0x2b0 fs/super.c:1814 do_new_mount+0x2be/0xb40 fs/namespace.c:3507 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4057 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034 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 -> #1 (&xfs_dquot_group_class){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 xfs_dqlock fs/xfs/xfs_dquot.h:131 [inline] xfs_qm_dqget_cache_insert fs/xfs/xfs_dquot.c:843 [inline] xfs_qm_dqget+0x370/0x6f0 fs/xfs/xfs_dquot.c:910 xfs_qm_quotacheck_dqadjust+0xea/0x5a0 fs/xfs/xfs_qm.c:1297 xfs_qm_dqusage_adjust+0x6a8/0x850 fs/xfs/xfs_qm.c:1426 xfs_iwalk_ag_recs+0x4e1/0x820 fs/xfs/xfs_iwalk.c:209 xfs_iwalk_run_callbacks+0x218/0x470 fs/xfs/xfs_iwalk.c:370 xfs_iwalk_ag+0xa9a/0xbb0 fs/xfs/xfs_iwalk.c:476 xfs_iwalk_ag_work+0xfb/0x1b0 fs/xfs/xfs_iwalk.c:625 xfs_pwork_work+0x7f/0x190 fs/xfs/xfs_pwork.c:47 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 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 -> #0 (&qinf->qi_tree_lock){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 xfs_qm_dqfree_one+0x66/0x170 fs/xfs/xfs_qm.c:1874 xfs_qm_shrink_scan+0x33f/0x400 fs/xfs/xfs_qm.c:558 do_shrink_slab+0x701/0x1160 mm/shrinker.c:437 shrink_slab+0x1093/0x14d0 mm/shrinker.c:664 shrink_one+0x43b/0x850 mm/vmscan.c:4836 shrink_many mm/vmscan.c:4897 [inline] lru_gen_shrink_node mm/vmscan.c:4975 [inline] shrink_node+0x37c5/0x3e50 mm/vmscan.c:5956 kswapd_shrink_node mm/vmscan.c:6785 [inline] balance_pgdat mm/vmscan.c:6977 [inline] kswapd+0x1ca9/0x3700 mm/vmscan.c:7246 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: Chain exists of: &qinf->qi_tree_lock --> &q->q_usage_counter(io)#20 --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&q->q_usage_counter(io)#20); lock(fs_reclaim); lock(&qinf->qi_tree_lock); *** DEADLOCK *** 1 lock held by kswapd0/88: #0: ffffffff8ea35ae0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6864 [inline] #0: ffffffff8ea35ae0 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbf1/0x3700 mm/vmscan.c:7246 stack backtrace: CPU: 1 UID: 0 PID: 88 Comm: kswapd0 Not tainted 6.12.0-next-20241119-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 xfs_qm_dqfree_one+0x66/0x170 fs/xfs/xfs_qm.c:1874 xfs_qm_shrink_scan+0x33f/0x400 fs/xfs/xfs_qm.c:558 do_shrink_slab+0x701/0x1160 mm/shrinker.c:437 shrink_slab+0x1093/0x14d0 mm/shrinker.c:664 shrink_one+0x43b/0x850 mm/vmscan.c:4836 shrink_many mm/vmscan.c:4897 [inline] lru_gen_shrink_node mm/vmscan.c:4975 [inline] shrink_node+0x37c5/0x3e50 mm/vmscan.c:5956 kswapd_shrink_node mm/vmscan.c:6785 [inline] balance_pgdat mm/vmscan.c:6977 [inline] kswapd+0x1ca9/0x3700 mm/vmscan.c:7246 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> --- 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
