====================================================== WARNING: possible circular locking dependency detected 6.12.0-syzkaller-12128-gf788b5ef1ca9 #0 Not tainted ------------------------------------------------------ syz.0.252/6952 is trying to acquire lock: ffff888043621790 (set->srcu){.+.+}-{0:0}, at: srcu_lock_sync include/linux/srcu.h:170 [inline] ffff888043621790 (set->srcu){.+.+}-{0:0}, at: __synchronize_srcu+0x99/0x2a0 kernel/rcu/srcutree.c:1418 but task is already holding lock: ffff888023e2d418 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_elv_switch_none block/blk-mq.c:4845 [inline] ffff888023e2d418 (&q->sysfs_lock){+.+.}-{4:4}, at: __blk_mq_update_nr_hw_queues+0x446/0x1460 block/blk-mq.c:4923 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&q->sysfs_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735 blk_mq_elv_switch_none block/blk-mq.c:4845 [inline] __blk_mq_update_nr_hw_queues+0x446/0x1460 block/blk-mq.c:4923 blk_mq_update_nr_hw_queues+0x2a/0x40 block/blk-mq.c:4983 nbd_start_device+0x15b/0xd70 drivers/block/nbd.c:1413 nbd_start_device_ioctl drivers/block/nbd.c:1464 [inline] __nbd_ioctl drivers/block/nbd.c:1539 [inline] nbd_ioctl+0x21a/0xfd0 drivers/block/nbd.c:1579 compat_blkdev_ioctl+0x2f7/0x750 block/ioctl.c:749 __do_compat_sys_ioctl+0x1cb/0x2c0 fs/ioctl.c:1004 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #5 (&q->q_usage_counter(io)#49){++++}-{0:0}: bio_queue_enter block/blk.h:75 [inline] blk_mq_submit_bio+0x1fb6/0x24c0 block/blk-mq.c:3091 __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 mpage_bio_submit_read fs/mpage.c:75 [inline] mpage_readahead+0x41d/0x590 fs/mpage.c:377 read_pages+0x1a8/0xdc0 mm/readahead.c:160 page_cache_ra_unbounded+0x3dc/0x750 mm/readahead.c:295 do_page_cache_ra mm/readahead.c:325 [inline] force_page_cache_ra+0x24b/0x340 mm/readahead.c:354 page_cache_sync_ra+0x110/0x9c0 mm/readahead.c:567 page_cache_sync_readahead include/linux/pagemap.h:1397 [inline] filemap_get_pages+0xd7b/0x1be0 mm/filemap.c:2546 filemap_read+0x3ca/0xd70 mm/filemap.c:2646 blkdev_read_iter+0x187/0x480 block/fops.c:770 new_sync_read fs/read_write.c:484 [inline] vfs_read+0x87f/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 -> #4 (mapping.invalidate_lock#2){.+.+}-{4:4}: down_read+0x9a/0x330 kernel/locking/rwsem.c:1524 filemap_invalidate_lock_shared include/linux/fs.h:873 [inline] page_cache_ra_unbounded+0x173/0x750 mm/readahead.c:226 do_page_cache_ra mm/readahead.c:325 [inline] page_cache_ra_order+0x7d9/0xc90 mm/readahead.c:525 do_sync_mmap_readahead mm/filemap.c:3203 [inline] filemap_fault+0x14a5/0x2820 mm/filemap.c:3344 __do_fault+0x10a/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 do_user_addr_fault+0x7a3/0x13f0 arch/x86/mm/fault.c:1389 handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:141 [inline] _inline_copy_from_user include/linux/uaccess.h:178 [inline] _copy_from_user+0x95/0xd0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] copy_from_sockptr_offset.constprop.0+0x106/0x190 include/linux/sockptr.h:48 copy_from_sockptr include/linux/sockptr.h:61 [inline] do_ip_setsockopt+0x198a/0x38c0 net/ipv4/ip_sockglue.c:1238 ip_setsockopt+0x59/0xf0 net/ipv4/ip_sockglue.c:1417 udp_setsockopt+0x7d/0xd0 net/ipv4/udp.c:2997 do_sock_setsockopt+0x222/0x480 net/socket.c:2313 __sys_setsockopt+0x1a0/0x230 net/socket.c:2338 __do_sys_setsockopt net/socket.c:2344 [inline] __se_sys_setsockopt net/socket.c:2341 [inline] __ia32_sys_setsockopt+0xbc/0x160 net/socket.c:2341 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #3 (sk_lock-AF_INET){+.+.}-{0:0}: lock_sock_nested+0x3a/0xf0 net/core/sock.c:3622 lock_sock include/net/sock.h:1617 [inline] inet_shutdown+0x67/0x440 net/ipv4/af_inet.c:905 nbd_mark_nsock_dead+0xae/0x5d0 drivers/block/nbd.c:314 sock_shutdown+0x17c/0x280 drivers/block/nbd.c:420 nbd_start_device_ioctl drivers/block/nbd.c:1474 [inline] __nbd_ioctl drivers/block/nbd.c:1539 [inline] nbd_ioctl+0xc7a/0xfd0 drivers/block/nbd.c:1579 compat_blkdev_ioctl+0x2f7/0x750 block/ioctl.c:749 __do_compat_sys_ioctl+0x1cb/0x2c0 fs/ioctl.c:1004 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #2 (&nsock->tx_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735 nbd_handle_cmd drivers/block/nbd.c:1079 [inline] nbd_queue_rq+0x424/0x1220 drivers/block/nbd.c:1143 blk_mq_dispatch_rq_list+0x443/0x1dc0 block/blk-mq.c:2119 __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:2353 blk_mq_dispatch_plug_list block/blk-mq.c:2863 [inline] blk_mq_flush_plug_list+0x673/0x1c60 block/blk-mq.c:2914 __blk_flush_plug+0x2c5/0x4b0 block/blk-core.c:1213 blk_finish_plug block/blk-core.c:1240 [inline] blk_finish_plug block/blk-core.c:1237 [inline] __submit_bio+0x439/0x540 block/blk-core.c:637 __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 submit_bh fs/buffer.c:2819 [inline] block_read_full_folio+0x812/0xa50 fs/buffer.c:2446 filemap_read_folio+0xc6/0x2a0 mm/filemap.c:2366 do_read_cache_folio+0x263/0x5c0 mm/filemap.c:3826 read_mapping_folio include/linux/pagemap.h:1011 [inline] read_part_sector+0xd3/0x410 block/partitions/core.c:722 adfspart_check_ICS+0xa7/0x8c0 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+0x6c6/0x14e0 block/partitions/core.c:693 blkdev_get_whole+0x187/0x290 block/bdev.c:707 bdev_open+0x2c7/0xe20 block/bdev.c:916 blkdev_open+0x329/0x400 block/fops.c:627 do_dentry_open+0xf59/0x1ea0 fs/open.c:945 vfs_open+0x82/0x3f0 fs/open.c:1075 do_open fs/namei.c:3828 [inline] path_openat+0x1e6a/0x2d60 fs/namei.c:3987 do_filp_open+0x20c/0x470 fs/namei.c:4014 do_sys_openat2+0x17a/0x1e0 fs/open.c:1402 do_sys_open fs/open.c:1417 [inline] __do_sys_openat fs/open.c:1433 [inline] __se_sys_openat fs/open.c:1428 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1428 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/0xa60 kernel/locking/mutex.c:735 nbd_queue_rq+0xbe/0x1220 drivers/block/nbd.c:1135 blk_mq_dispatch_rq_list+0x443/0x1dc0 block/blk-mq.c:2119 __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:2353 blk_mq_dispatch_plug_list block/blk-mq.c:2863 [inline] blk_mq_flush_plug_list+0x673/0x1c60 block/blk-mq.c:2914 __blk_flush_plug+0x2c5/0x4b0 block/blk-core.c:1213 blk_finish_plug block/blk-core.c:1240 [inline] blk_finish_plug block/blk-core.c:1237 [inline] __submit_bio+0x439/0x540 block/blk-core.c:637 __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 submit_bh fs/buffer.c:2819 [inline] block_read_full_folio+0x812/0xa50 fs/buffer.c:2446 filemap_read_folio+0xc6/0x2a0 mm/filemap.c:2366 do_read_cache_folio+0x263/0x5c0 mm/filemap.c:3826 read_mapping_folio include/linux/pagemap.h:1011 [inline] read_part_sector+0xd3/0x410 block/partitions/core.c:722 adfspart_check_ICS+0xa7/0x8c0 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+0x6c6/0x14e0 block/partitions/core.c:693 blkdev_get_whole+0x187/0x290 block/bdev.c:707 bdev_open+0x2c7/0xe20 block/bdev.c:916 blkdev_open+0x329/0x400 block/fops.c:627 do_dentry_open+0xf59/0x1ea0 fs/open.c:945 vfs_open+0x82/0x3f0 fs/open.c:1075 do_open fs/namei.c:3828 [inline] path_openat+0x1e6a/0x2d60 fs/namei.c:3987 do_filp_open+0x20c/0x470 fs/namei.c:4014 do_sys_openat2+0x17a/0x1e0 fs/open.c:1402 do_sys_open fs/open.c:1417 [inline] __do_sys_openat fs/open.c:1433 [inline] __se_sys_openat fs/open.c:1428 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1428 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: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_sync+0xf5/0x190 kernel/locking/lockdep.c:5897 srcu_lock_sync include/linux/srcu.h:170 [inline] __synchronize_srcu+0xa9/0x2a0 kernel/rcu/srcutree.c:1418 blk_mq_wait_quiesce_done block/blk-mq.c:290 [inline] blk_mq_wait_quiesce_done block/blk-mq.c:287 [inline] blk_mq_quiesce_queue block/blk-mq.c:310 [inline] blk_mq_quiesce_queue+0x149/0x1b0 block/blk-mq.c:305 elevator_disable+0x70/0x490 block/elevator.c:671 blk_mq_elv_switch_none block/blk-mq.c:4859 [inline] __blk_mq_update_nr_hw_queues+0x3bb/0x1460 block/blk-mq.c:4923 blk_mq_update_nr_hw_queues+0x2a/0x40 block/blk-mq.c:4983 nbd_start_device+0x15b/0xd70 drivers/block/nbd.c:1413 nbd_start_device_ioctl drivers/block/nbd.c:1464 [inline] __nbd_ioctl drivers/block/nbd.c:1539 [inline] nbd_ioctl+0x21a/0xfd0 drivers/block/nbd.c:1579 compat_blkdev_ioctl+0x2f7/0x750 block/ioctl.c:749 __do_compat_sys_ioctl+0x1cb/0x2c0 fs/ioctl.c:1004 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e 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.0.252/6952: #0: ffff888040ff8998 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x151/0xfd0 drivers/block/nbd.c:1572 #1: ffff888040ff88d8 (&set->tag_list_lock){+.+.}-{4:4}, at: blk_mq_update_nr_hw_queues+0x20/0x40 block/blk-mq.c:4982 #2: ffff888023e2cee8 (&q->q_usage_counter(io)#49){++++}-{0:0}, at: blk_mq_freeze_queue block/blk-mq.c:212 [inline] #2: ffff888023e2cee8 (&q->q_usage_counter(io)#49){++++}-{0:0}, at: __blk_mq_update_nr_hw_queues+0x1fc/0x1460 block/blk-mq.c:4916 #3: ffff888023e2cf20 (&q->q_usage_counter(queue)#33){+.+.}-{0:0}, at: blk_mq_freeze_queue block/blk-mq.c:212 [inline] #3: ffff888023e2cf20 (&q->q_usage_counter(queue)#33){+.+.}-{0:0}, at: __blk_mq_update_nr_hw_queues+0x1fc/0x1460 block/blk-mq.c:4916 #4: ffff888023e2d418 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_elv_switch_none block/blk-mq.c:4845 [inline] #4: ffff888023e2d418 (&q->sysfs_lock){+.+.}-{4:4}, at: __blk_mq_update_nr_hw_queues+0x446/0x1460 block/blk-mq.c:4923 stack backtrace: CPU: 2 UID: 0 PID: 6952 Comm: syz.0.252 Not tainted 6.12.0-syzkaller-12128-gf788b5ef1ca9 #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_sync+0xf5/0x190 kernel/locking/lockdep.c:5897 srcu_lock_sync include/linux/srcu.h:170 [inline] __synchronize_srcu+0xa9/0x2a0 kernel/rcu/srcutree.c:1418 blk_mq_wait_quiesce_done block/blk-mq.c:290 [inline] blk_mq_wait_quiesce_done block/blk-mq.c:287 [inline] blk_mq_quiesce_queue block/blk-mq.c:310 [inline] blk_mq_quiesce_queue+0x149/0x1b0 block/blk-mq.c:305 elevator_disable+0x70/0x490 block/elevator.c:671 blk_mq_elv_switch_none block/blk-mq.c:4859 [inline] __blk_mq_update_nr_hw_queues+0x3bb/0x1460 block/blk-mq.c:4923 blk_mq_update_nr_hw_queues+0x2a/0x40 block/blk-mq.c:4983 nbd_start_device+0x15b/0xd70 drivers/block/nbd.c:1413 nbd_start_device_ioctl drivers/block/nbd.c:1464 [inline] __nbd_ioctl drivers/block/nbd.c:1539 [inline] nbd_ioctl+0x21a/0xfd0 drivers/block/nbd.c:1579 compat_blkdev_ioctl+0x2f7/0x750 block/ioctl.c:749 __do_compat_sys_ioctl+0x1cb/0x2c0 fs/ioctl.c:1004 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf73ae579 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:00000000f507557c EFLAGS: 00000292 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000000ab03 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 block nbd0: shutting down sockets ---------------- 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