====================================================== WARNING: possible circular locking dependency detected 6.12.0-syzkaller-07834-g06afb0f36106 #0 Not tainted ------------------------------------------------------ kswapd0/112 is trying to acquire lock: ffff88801f3f1438 (&q->q_usage_counter(io)#68){++++}-{0:0}, at: bio_queue_enter block/blk.h:79 [inline] ffff88801f3f1438 (&q->q_usage_counter(io)#68){++++}-{0:0}, at: blk_mq_submit_bio+0x7ca/0x24c0 block/blk-mq.c:3092 but task is already holding lock: ffffffff8df4de60 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0xcd9/0x18f0 mm/vmscan.c:6976 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}-{0:0}: __fs_reclaim_acquire mm/page_alloc.c:3851 [inline] fs_reclaim_acquire+0x102/0x150 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] __do_kmalloc_node mm/slub.c:4263 [inline] __kmalloc_node_noprof+0xb7/0x440 mm/slub.c:4270 __kvmalloc_node_noprof+0xad/0x1a0 mm/util.c:658 sbitmap_init_node+0x1ca/0x770 lib/sbitmap.c:132 scsi_realloc_sdev_budget_map+0x2c7/0x610 drivers/scsi/scsi_scan.c:246 scsi_add_lun+0x11b4/0x1fd0 drivers/scsi/scsi_scan.c:1106 scsi_probe_and_add_lun+0x4fa/0xda0 drivers/scsi/scsi_scan.c:1287 __scsi_add_device+0x24b/0x290 drivers/scsi/scsi_scan.c:1622 ata_scsi_scan_host+0x215/0x780 drivers/ata/libata-scsi.c:4575 async_run_entry_fn+0x9c/0x530 kernel/async.c:129 process_one_work+0x958/0x1b30 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #0 (&q->q_usage_counter(io)#68){++++}-{0:0}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain kernel/locking/lockdep.c:3904 [inline] __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __bio_queue_enter+0x4c6/0x740 block/blk-core.c:361 bio_queue_enter block/blk.h:79 [inline] blk_mq_submit_bio+0x7ca/0x24c0 block/blk-mq.c:3092 __submit_bio+0x384/0x540 block/blk-core.c:629 __submit_bio_noacct_mq block/blk-core.c:710 [inline] submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:739 submit_bio_noacct+0x93a/0x1e20 block/blk-core.c:868 swap_writepage_bdev_async mm/page_io.c:449 [inline] __swap_writepage+0x3a3/0xf50 mm/page_io.c:472 swap_writepage+0x403/0x1040 mm/page_io.c:288 pageout+0x3b2/0xaa0 mm/vmscan.c:689 shrink_folio_list+0x3025/0x42d0 mm/vmscan.c:1367 evict_folios+0x6d6/0x1970 mm/vmscan.c:4589 try_to_shrink_lruvec+0x612/0x9b0 mm/vmscan.c:4784 shrink_one+0x3e3/0x7b0 mm/vmscan.c:4822 shrink_many mm/vmscan.c:4885 [inline] lru_gen_shrink_node mm/vmscan.c:4963 [inline] shrink_node+0xbbc/0x3ed0 mm/vmscan.c:5943 kswapd_shrink_node mm/vmscan.c:6771 [inline] balance_pgdat+0xc1f/0x18f0 mm/vmscan.c:6963 kswapd+0x5f8/0xc30 mm/vmscan.c:7232 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 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(&q->q_usage_counter(io)#68); lock(fs_reclaim); rlock(&q->q_usage_counter(io)#68); *** DEADLOCK *** 1 lock held by kswapd0/112: #0: ffffffff8df4de60 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0xcd9/0x18f0 mm/vmscan.c:6976 stack backtrace: CPU: 3 UID: 0 PID: 112 Comm: kswapd0 Not tainted 6.12.0-syzkaller-07834-g06afb0f36106 #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+0x116/0x1f0 lib/dump_stack.c:120 print_circular_bug+0x41c/0x610 kernel/locking/lockdep.c:2074 check_noncircular+0x31a/0x400 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 kernel/locking/lockdep.c:3904 [inline] __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __bio_queue_enter+0x4c6/0x740 block/blk-core.c:361 bio_queue_enter block/blk.h:79 [inline] blk_mq_submit_bio+0x7ca/0x24c0 block/blk-mq.c:3092 __submit_bio+0x384/0x540 block/blk-core.c:629 __submit_bio_noacct_mq block/blk-core.c:710 [inline] submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:739 submit_bio_noacct+0x93a/0x1e20 block/blk-core.c:868 swap_writepage_bdev_async mm/page_io.c:449 [inline] __swap_writepage+0x3a3/0xf50 mm/page_io.c:472 swap_writepage+0x403/0x1040 mm/page_io.c:288 pageout+0x3b2/0xaa0 mm/vmscan.c:689 shrink_folio_list+0x3025/0x42d0 mm/vmscan.c:1367 evict_folios+0x6d6/0x1970 mm/vmscan.c:4589 try_to_shrink_lruvec+0x612/0x9b0 mm/vmscan.c:4784 shrink_one+0x3e3/0x7b0 mm/vmscan.c:4822 shrink_many mm/vmscan.c:4885 [inline] lru_gen_shrink_node mm/vmscan.c:4963 [inline] shrink_node+0xbbc/0x3ed0 mm/vmscan.c:5943 kswapd_shrink_node mm/vmscan.c:6771 [inline] balance_pgdat+0xc1f/0x18f0 mm/vmscan.c:6963 kswapd+0x5f8/0xc30 mm/vmscan.c:7232 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244