====================================================== WARNING: possible circular locking dependency detected 6.13.0-syzkaller-01268-gc0e75905caf3 #0 Not tainted ------------------------------------------------------ syz.0.1261/11859 is trying to acquire lock: ffff888141ffcf90 (set->srcu){.+.+}-{0:0}, at: srcu_lock_sync include/linux/srcu.h:176 [inline] ffff888141ffcf90 (set->srcu){.+.+}-{0:0}, at: __synchronize_srcu+0x99/0x2a0 kernel/rcu/srcutree.c:1418 but task is already holding lock: ffff888143b3e7a8 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_elv_switch_none block/blk-mq.c:4936 [inline] ffff888143b3e7a8 (&q->sysfs_lock){+.+.}-{4:4}, at: __blk_mq_update_nr_hw_queues block/blk-mq.c:5014 [inline] ffff888143b3e7a8 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_update_nr_hw_queues+0x42b/0x1290 block/blk-mq.c:5065 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #7 (&q->sysfs_lock){+.+.}-{4:4} : __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 blk_mq_elv_switch_none block/blk-mq.c:4936 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:5014 [inline] blk_mq_update_nr_hw_queues+0x42b/0x1290 block/blk-mq.c:5065 nbd_start_device+0x172/0xcc0 drivers/block/nbd.c:1475 nbd_start_device_ioctl drivers/block/nbd.c:1526 [inline] __nbd_ioctl drivers/block/nbd.c:1601 [inline] nbd_ioctl+0x21a/0xd60 drivers/block/nbd.c:1641 blkdev_ioctl+0x279/0x6d0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #6 (&q->q_usage_counter(io)#49){++++}-{0:0}: bio_queue_enter block/blk.h:77 [inline] blk_mq_submit_bio+0x20db/0x25f0 block/blk-mq.c:3091 __submit_bio+0x3d1/0x690 block/blk-core.c:629 __submit_bio_noacct_mq block/blk-core.c:716 [inline] submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:745 submit_bio_noacct+0x50d/0x1ec0 block/blk-core.c:868 submit_bh fs/buffer.c:2819 [inline] block_read_full_folio+0x812/0xa50 fs/buffer.c:2446 filemap_read_folio+0xc9/0x2a0 mm/filemap.c:2357 filemap_update_page mm/filemap.c:2441 [inline] filemap_get_pages+0x155f/0x1be0 mm/filemap.c:2562 filemap_read+0x3ca/0xd70 mm/filemap.c:2637 blkdev_read_iter+0x187/0x480 block/fops.c:795 new_sync_read fs/read_write.c:484 [inline] vfs_read+0x882/0xbe0 fs/read_write.c:565 ksys_read+0x12b/0x250 fs/read_write.c:708 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #5 (mapping.invalidate_lock#2){.+.+}-{4:4}: down_read+0x9a/0x330 kernel/locking/rwsem.c:1524 filemap_invalidate_lock_shared include/linux/fs.h:887 [inline] filemap_fault+0x62c/0x2820 mm/filemap.c:3342 __do_fault+0x10d/0x490 mm/memory.c:4907 do_read_fault mm/memory.c:5322 [inline] do_fault mm/memory.c:5456 [inline] do_pte_missing+0xebd/0x3e00 mm/memory.c:3979 handle_pte_fault mm/memory.c:5801 [inline] __handle_mm_fault+0x103c/0x2a40 mm/memory.c:5944 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6112 faultin_page mm/gup.c:1196 [inline] __get_user_pages+0x8d9/0x3b50 mm/gup.c:1494 populate_vma_page_range+0x27f/0x3a0 mm/gup.c:1932 __mm_populate+0x1d6/0x380 mm/gup.c:2035 do_mlock+0x448/0x810 mm/mlock.c:653 __do_sys_mlock mm/mlock.c:661 [inline] __se_sys_mlock mm/mlock.c:659 [inline] __x64_sys_mlock+0x59/0x80 mm/mlock.c:659 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (&mm->mmap_lock){++++}-{4:4}: __might_fault mm/memory.c:6751 [inline] __might_fault+0x11b/0x190 mm/memory.c:6744 _copy_from_iter+0x1c4/0x1560 lib/iov_iter.c:259 copy_from_iter include/linux/uio.h:228 [inline] copy_from_iter_full include/linux/uio.h:245 [inline] skb_do_copy_data_nocache include/net/sock.h:2193 [inline] skb_copy_to_page_nocache include/net/sock.h:2219 [inline] tcp_sendmsg_locked+0x193b/0x3770 net/ipv4/tcp.c:1222 tcp_sendmsg+0x2e/0x50 net/ipv4/tcp.c:1358 inet_sendmsg+0xb9/0x140 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg net/socket.c:726 [inline] sock_write_iter+0x4ac/0x5b0 net/socket.c:1147 new_sync_write fs/read_write.c:586 [inline] vfs_write+0x5b1/0x1150 fs/read_write.c:679 ksys_write+0x207/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (sk_lock-AF_INET){+.+.}-{0:0}: lock_sock_nested+0x3a/0xf0 net/core/sock.c:3625 lock_sock include/net/sock.h:1623 [inline] inet_shutdown+0x67/0x440 net/ipv4/af_inet.c:905 nbd_mark_nsock_dead+0xae/0x5d0 drivers/block/nbd.c:318 recv_work+0x691/0xaa0 drivers/block/nbd.c:1018 process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x2c4/0x3a0 kernel/kthread.c:389 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #2 (&nsock->tx_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 nbd_handle_cmd drivers/block/nbd.c:1140 [inline] nbd_queue_rq+0x424/0x1220 drivers/block/nbd.c:1204 blk_mq_dispatch_rq_list+0x446/0x1dc0 block/blk-mq.c:2120 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:170 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline] __blk_mq_sched_dispatch_requests+0xcdf/0x1620 block/blk-mq-sched.c:309 blk_mq_sched_dispatch_requests+0xd8/0x1b0 block/blk-mq-sched.c:331 blk_mq_run_hw_queue+0x239/0x670 block/blk-mq.c:2354 blk_mq_dispatch_plug_list block/blk-mq.c:2866 [inline] blk_mq_flush_plug_list+0x673/0x1c60 block/blk-mq.c:2917 __blk_flush_plug+0x2c5/0x4b0 block/blk-core.c:1214 blk_finish_plug block/blk-core.c:1241 [inline] blk_finish_plug block/blk-core.c:1238 [inline] __submit_bio+0x547/0x690 block/blk-core.c:643 __submit_bio_noacct_mq block/blk-core.c:716 [inline] submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:745 submit_bio_noacct+0x50d/0x1ec0 block/blk-core.c:868 submit_bh fs/buffer.c:2819 [inline] block_read_full_folio+0x812/0xa50 fs/buffer.c:2446 filemap_read_folio+0xc9/0x2a0 mm/filemap.c:2357 do_read_cache_folio+0x263/0x5c0 mm/filemap.c:3817 read_mapping_folio include/linux/pagemap.h:1011 [inline] read_part_sector+0xd4/0x310 block/partitions/core.c:722 adfspart_check_ICS+0x94/0x940 block/partitions/acorn.c:360 check_partition block/partitions/core.c:141 [inline] blk_add_partitions block/partitions/core.c:589 [inline] bdev_disk_changed+0x722/0x1520 block/partitions/core.c:693 blkdev_get_whole+0x187/0x290 block/bdev.c:706 bdev_open+0x2c7/0xe20 block/bdev.c:915 blkdev_open+0x272/0x3f0 block/fops.c:652 do_dentry_open+0xf5c/0x1ea0 fs/open.c:938 vfs_open+0x82/0x3f0 fs/open.c:1068 do_open fs/namei.c:3828 [inline] path_openat+0x1e81/0x2d70 fs/namei.c:3987 do_filp_open+0x20c/0x470 fs/namei.c:4014 do_sys_openat2+0x17a/0x1e0 fs/open.c:1395 do_sys_open fs/open.c:1410 [inline] __do_sys_openat fs/open.c:1426 [inline] __se_sys_openat fs/open.c:1421 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1421 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&cmd->lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 nbd_queue_rq+0xbe/0x1220 drivers/block/nbd.c:1196 blk_mq_dispatch_rq_list+0x446/0x1dc0 block/blk-mq.c:2120 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:170 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline] __blk_mq_sched_dispatch_requests+0xcdf/0x1620 block/blk-mq-sched.c:309 blk_mq_sched_dispatch_requests+0xd8/0x1b0 block/blk-mq-sched.c:331 blk_mq_run_hw_queue+0x239/0x670 block/blk-mq.c:2354 blk_mq_dispatch_plug_list block/blk-mq.c:2866 [inline] blk_mq_flush_plug_list+0x673/0x1c60 block/blk-mq.c:2917 __blk_flush_plug+0x2c5/0x4b0 block/blk-core.c:1214 blk_finish_plug block/blk-core.c:1241 [inline] blk_finish_plug block/blk-core.c:1238 [inline] __submit_bio+0x547/0x690 block/blk-core.c:643 __submit_bio_noacct_mq block/blk-core.c:716 [inline] submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:745 submit_bio_noacct+0x50d/0x1ec0 block/blk-core.c:868 submit_bh fs/buffer.c:2819 [inline] block_read_full_folio+0x812/0xa50 fs/buffer.c:2446 filemap_read_folio+0xc9/0x2a0 mm/filemap.c:2357 do_read_cache_folio+0x263/0x5c0 mm/filemap.c:3817 read_mapping_folio include/linux/pagemap.h:1011 [inline] read_part_sector+0xd4/0x310 block/partitions/core.c:722 adfspart_check_ICS+0x94/0x940 block/partitions/acorn.c:360 check_partition block/partitions/core.c:141 [inline] blk_add_partitions block/partitions/core.c:589 [inline] bdev_disk_changed+0x722/0x1520 block/partitions/core.c:693 blkdev_get_whole+0x187/0x290 block/bdev.c:706 bdev_open+0x2c7/0xe20 block/bdev.c:915 blkdev_open+0x272/0x3f0 block/fops.c:652 do_dentry_open+0xf5c/0x1ea0 fs/open.c:938 vfs_open+0x82/0x3f0 fs/open.c:1068 do_open fs/namei.c:3828 [inline] path_openat+0x1e81/0x2d70 fs/namei.c:3987 do_filp_open+0x20c/0x470 fs/namei.c:4014 do_sys_openat2+0x17a/0x1e0 fs/open.c:1395 do_sys_open fs/open.c:1410 [inline] __do_sys_openat fs/open.c:1426 [inline] __se_sys_openat fs/open.c:1421 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1421 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (set->srcu){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain kernel/locking/lockdep.c:3906 [inline] __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228 lock_sync+0xf5/0x190 kernel/locking/lockdep.c:5899 srcu_lock_sync include/linux/srcu.h:176 [inline] __synchronize_srcu+0xa9/0x2a0 kernel/rcu/srcutree.c:1418 blk_mq_wait_quiesce_done block/blk-mq.c:293 [inline] blk_mq_wait_quiesce_done block/blk-mq.c:290 [inline] blk_mq_quiesce_queue block/blk-mq.c:313 [inline] blk_mq_quiesce_queue+0x149/0x1b0 block/blk-mq.c:308 elevator_disable+0x70/0x490 block/elevator.c:657 blk_mq_elv_switch_none block/blk-mq.c:4950 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:5014 [inline] blk_mq_update_nr_hw_queues+0x3a0/0x1290 block/blk-mq.c:5065 nbd_start_device+0x172/0xcc0 drivers/block/nbd.c:1475 nbd_start_device_ioctl drivers/block/nbd.c:1526 [inline] __nbd_ioctl drivers/block/nbd.c:1601 [inline] nbd_ioctl+0x21a/0xd60 drivers/block/nbd.c:1641 blkdev_ioctl+0x279/0x6d0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: set->srcu --> &q->q_usage_counter(io)#49 --> &q->sysfs_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->sysfs_lock); lock(&q->q_usage_counter(io)#49); lock(&q->sysfs_lock); sync( set->srcu); *** DEADLOCK *** 5 locks held by syz.0.1261/11859: #0: ffff88802583d198 (&nbd->config_lock){+.+.}-{4:4} , at: nbd_ioctl+0x151/0xd60 drivers/block/nbd.c:1634 #1: ffff88802583d0d8 (&set->tag_list_lock){+.+.}-{4:4}, at: blk_mq_update_nr_hw_queues+0x8f/0x1290 block/blk-mq.c:5064 #2: ffff888143b3e278 (&q->q_usage_counter(io)#49){++++}-{0:0}, at: blk_mq_freeze_queue block/blk-mq.c:215 [inline] #2: ffff888143b3e278 (&q->q_usage_counter(io)#49){++++}-{0:0}, at: __blk_mq_update_nr_hw_queues block/blk-mq.c:5007 [inline] #2: ffff888143b3e278 (&q->q_usage_counter(io)#49){++++}-{0:0}, at: blk_mq_update_nr_hw_queues+0x1e7/0x1290 block/blk-mq.c:5065 #3: ffff888143b3e2b0 (&q->q_usage_counter(queue)#33){+.+.}-{0:0}, at: blk_mq_freeze_queue block/blk-mq.c:215 [inline] #3: ffff888143b3e2b0 (&q->q_usage_counter(queue)#33){+.+.}-{0:0}, at: __blk_mq_update_nr_hw_queues block/blk-mq.c:5007 [inline] #3: ffff888143b3e2b0 (&q->q_usage_counter(queue)#33){+.+.}-{0:0}, at: blk_mq_update_nr_hw_queues+0x1e7/0x1290 block/blk-mq.c:5065 #4: ffff888143b3e7a8 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_elv_switch_none block/blk-mq.c:4936 [inline] #4: ffff888143b3e7a8 (&q->sysfs_lock){+.+.}-{4:4}, at: __blk_mq_update_nr_hw_queues block/blk-mq.c:5014 [inline] #4: ffff888143b3e7a8 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_update_nr_hw_queues+0x42b/0x1290 block/blk-mq.c:5065 stack backtrace: CPU: 0 UID: 0 PID: 11859 Comm: syz.0.1261 Not tainted 6.13.0-syzkaller-01268-gc0e75905caf3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_circular_bug+0x490/0x760 kernel/locking/lockdep.c:2076 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2208 check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain kernel/locking/lockdep.c:3906 [inline] __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228 lock_sync+0xf5/0x190 kernel/locking/lockdep.c:5899 srcu_lock_sync include/linux/srcu.h:176 [inline] __synchronize_srcu+0xa9/0x2a0 kernel/rcu/srcutree.c:1418 blk_mq_wait_quiesce_done block/blk-mq.c:293 [inline] blk_mq_wait_quiesce_done block/blk-mq.c:290 [inline] blk_mq_quiesce_queue block/blk-mq.c:313 [inline] blk_mq_quiesce_queue+0x149/0x1b0 block/blk-mq.c:308 elevator_disable+0x70/0x490 block/elevator.c:657 blk_mq_elv_switch_none block/blk-mq.c:4950 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:5014 [inline] blk_mq_update_nr_hw_queues+0x3a0/0x1290 block/blk-mq.c:5065 nbd_start_device+0x172/0xcc0 drivers/block/nbd.c:1475 nbd_start_device_ioctl drivers/block/nbd.c:1526 [inline] __nbd_ioctl drivers/block/nbd.c:1601 [inline] nbd_ioctl+0x21a/0xd60 drivers/block/nbd.c:1641 blkdev_ioctl+0x279/0x6d0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa05c585d29 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:00007fa05d332038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fa05c775fa0 RCX: 00007fa05c585d29 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000006 RBP: 00007fa05c601b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa05c775fa0 R15: 00007ffc4d0ed258 block nbd0: shutting down sockets