loop0: detected capacity change from 0 to 32768 XFS (loop0): Mounting V5 Filesystem d7dc424e-7990-42cb-9f91-9cb7200a101d XFS (loop0): Ending clean mount XFS (loop0): Quotacheck needed: Please wait. XFS (loop0): Quotacheck: Done. loop0: detected capacity change from 32768 to 0 ====================================================== WARNING: possible circular locking dependency detected 6.12.0-syzkaller-00971-g158f238aa69d #0 Not tainted ------------------------------------------------------ syz.0.0/5327 is trying to acquire lock: ffffffff8ea39a60 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:318 [inline] ffffffff8ea39a60 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:4036 [inline] ffffffff8ea39a60 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:4114 [inline] ffffffff8ea39a60 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_cache_noprof+0x3d/0x2c0 mm/slub.c:4290 but task is already holding lock: ffff888033821e00 (&q->q_usage_counter(io)#17){++++}-{0:0}, at: loop_set_status+0x1e4/0x8f0 drivers/block/loop.c:1267 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&q->q_usage_counter(io)#17){++++}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 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 xfs_buf_ioapply_map+0x461/0x5d0 fs/xfs/xfs_buf.c:1586 _xfs_buf_ioapply+0x307/0x660 fs/xfs/xfs_buf.c:1674 __xfs_buf_submit+0x34f/0x7f0 fs/xfs/xfs_buf.c:1758 xfs_buf_submit fs/xfs/xfs_buf.c:61 [inline] _xfs_buf_read fs/xfs/xfs_buf.c:809 [inline] xfs_buf_read_map+0x431/0xa60 fs/xfs/xfs_buf.c:873 xfs_trans_read_buf_map+0x260/0xad0 fs/xfs/xfs_trans_buf.c:289 xfs_trans_read_buf fs/xfs/xfs_trans.h:212 [inline] xfs_read_agf+0x2e2/0x680 fs/xfs/libxfs/xfs_alloc.c:3367 xfs_alloc_read_agf+0x1c7/0xcb0 fs/xfs/libxfs/xfs_alloc.c:3401 xfs_alloc_fix_freelist+0x614/0x1b90 fs/xfs/libxfs/xfs_alloc.c:2863 xfs_alloc_vextent_prepare_ag+0xf7/0x6b0 fs/xfs/libxfs/xfs_alloc.c:3532 xfs_alloc_vextent_iterate_ags+0x140/0x950 fs/xfs/libxfs/xfs_alloc.c:3717 xfs_alloc_vextent_start_ag+0x3f6/0x950 fs/xfs/libxfs/xfs_alloc.c:3806 xfs_bmap_btalloc_best_length fs/xfs/libxfs/xfs_bmap.c:3731 [inline] xfs_bmap_btalloc fs/xfs/libxfs/xfs_bmap.c:3776 [inline] xfs_bmapi_allocate+0x18f6/0x3450 fs/xfs/libxfs/xfs_bmap.c:4189 xfs_bmapi_write+0xbac/0x1b40 fs/xfs/libxfs/xfs_bmap.c:4518 xfs_dquot_disk_alloc+0x5f4/0xe20 fs/xfs/xfs_dquot.c:350 xfs_qm_dqread+0x1a3/0x650 fs/xfs/xfs_dquot.c:689 xfs_qm_dqget+0x2bb/0x6f0 fs/xfs/xfs_dquot.c:901 xfs_qm_quotacheck_dqadjust+0xea/0x5a0 fs/xfs/xfs_qm.c:1101 xfs_qm_dqusage_adjust+0x4db/0x6f0 fs/xfs/xfs_qm.c:1220 xfs_iwalk_ag_recs+0x4e0/0x860 fs/xfs/xfs_iwalk.c:213 xfs_iwalk_run_callbacks+0x218/0x470 fs/xfs/xfs_iwalk.c:371 xfs_iwalk_ag+0xa39/0xb50 fs/xfs/xfs_iwalk.c:477 xfs_iwalk_ag_work+0xfb/0x1b0 fs/xfs/xfs_iwalk.c:619 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 -> #1 (&xfs_nondir_ilock_class#3){++++}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 down_write_nested+0xa2/0x220 kernel/locking/rwsem.c:1693 xfs_reclaim_inode fs/xfs/xfs_icache.c:981 [inline] xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1675 [inline] xfs_icwalk_ag+0x120e/0x1ad0 fs/xfs/xfs_icache.c:1757 xfs_icwalk fs/xfs/xfs_icache.c:1805 [inline] xfs_reclaim_inodes_nr+0x2ae/0x390 fs/xfs/xfs_icache.c:1047 super_cache_scan+0x40f/0x4b0 fs/super.c:227 do_shrink_slab+0x701/0x1160 mm/shrinker.c:437 shrink_slab+0x1093/0x14d0 mm/shrinker.c:664 shrink_one+0x43b/0x850 mm/vmscan.c:4824 shrink_many mm/vmscan.c:4885 [inline] lru_gen_shrink_node mm/vmscan.c:4963 [inline] shrink_node+0x3789/0x3e10 mm/vmscan.c:5943 kswapd_shrink_node mm/vmscan.c:6771 [inline] balance_pgdat mm/vmscan.c:6963 [inline] kswapd+0x1ca9/0x3700 mm/vmscan.c:7232 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 (fs_reclaim){+.+.}-{0:0}: 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+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __fs_reclaim_acquire mm/page_alloc.c:3851 [inline] fs_reclaim_acquire+0x88/0x130 mm/page_alloc.c:3865 might_alloc include/linux/sched/mm.h:318 [inline] slab_pre_alloc_hook mm/slub.c:4036 [inline] slab_alloc_node mm/slub.c:4114 [inline] __kmalloc_cache_noprof+0x3d/0x2c0 mm/slub.c:4290 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [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 other info that might help us debug this: Chain exists of: fs_reclaim --> &xfs_nondir_ilock_class#3 --> &q->q_usage_counter(io)#17 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->q_usage_counter(io)#17); lock(&xfs_nondir_ilock_class#3); lock(&q->q_usage_counter(io)#17); lock(fs_reclaim); *** DEADLOCK *** 3 locks held by syz.0.0/5327: #0: ffff888033ed3360 (&lo->lo_mutex){+.+.}-{3:3}, at: loop_set_status+0x2a/0x8f0 drivers/block/loop.c:1251 #1: ffff888033821e00 (&q->q_usage_counter(io)#17){++++}-{0:0}, at: loop_set_status+0x1e4/0x8f0 drivers/block/loop.c:1267 #2: ffff888033821e38 (&q->q_usage_counter(queue)){+.+.}-{0:0}, at: loop_set_status+0x1e4/0x8f0 drivers/block/loop.c:1267 stack backtrace: CPU: 0 UID: 0 PID: 5327 Comm: syz.0.0 Not tainted 6.12.0-syzkaller-00971-g158f238aa69d #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: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+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __fs_reclaim_acquire mm/page_alloc.c:3851 [inline] fs_reclaim_acquire+0x88/0x130 mm/page_alloc.c:3865 might_alloc include/linux/sched/mm.h:318 [inline] slab_pre_alloc_hook mm/slub.c:4036 [inline] slab_alloc_node mm/slub.c:4114 [inline] __kmalloc_cache_noprof+0x3d/0x2c0 mm/slub.c:4290 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [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 RIP: 0033:0x7f87eef7e759 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f87efcd4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f87ef135f80 RCX: 00007f87eef7e759 RDX: 00000000200000c0 RSI: 0000000000004c02 RDI: 0000000000000005 RBP: 00007f87eeff175e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f87ef135f80 R15: 00007ffd9fcf3528 syz.0.0 (5327) used greatest stack depth: 17488 bytes left