block nbd5: shutting down sockets ====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc1-syzkaller-g19272b37aa4f #0 Not tainted ------------------------------------------------------ syz.5.329/8699 is trying to acquire lock: ffffffff885421e8 (pcpu_alloc_mutex){+.+.}-{4:4}, at: pcpu_alloc_noprof+0xd64/0x1d3e mm/percpu.c:1782 but task is already holding lock: ffffaf8019f9e228 (&q->q_usage_counter(io)#24){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave block/blk-mq.c:205 [inline] ffffaf8019f9e228 (&q->q_usage_counter(io)#24){++++}-{0:0}, at: __blk_mq_update_nr_hw_queues block/blk-mq.c:4993 [inline] ffffaf8019f9e228 (&q->q_usage_counter(io)#24){++++}-{0:0}, at: blk_mq_update_nr_hw_queues+0x23a/0xb86 block/blk-mq.c:5043 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&q->q_usage_counter(io)#24){++++}-{0:0}: lock_acquire kernel/locking/lockdep.c:5871 [inline] lock_acquire+0x1ac/0x448 kernel/locking/lockdep.c:5828 blk_alloc_queue+0x5c4/0x6dc block/blk-core.c:461 blk_mq_alloc_queue+0x170/0x268 block/blk-mq.c:4396 __blk_mq_alloc_disk+0x2a/0x118 block/blk-mq.c:4443 nbd_dev_add+0x466/0xb38 drivers/block/nbd.c:1933 nbd_init+0x3f4/0x41a drivers/block/nbd.c:2670 do_one_initcall+0x1a2/0xae4 init/main.c:1273 do_initcall_level init/main.c:1335 [inline] do_initcalls init/main.c:1351 [inline] do_basic_setup init/main.c:1370 [inline] kernel_init_freeable+0x6e4/0x78c init/main.c:1583 kernel_init+0x28/0x24c init/main.c:1473 ret_from_fork_kernel+0x2a/0xbb2 arch/riscv/kernel/process.c:214 ret_from_fork_kernel_asm+0x16/0x18 arch/riscv/kernel/entry.S:327 -> #1 (fs_reclaim){+.+.}-{0:0}: lock_acquire kernel/locking/lockdep.c:5871 [inline] lock_acquire+0x1ac/0x448 kernel/locking/lockdep.c:5828 __fs_reclaim_acquire mm/page_alloc.c:4045 [inline] fs_reclaim_acquire+0xd0/0x106 mm/page_alloc.c:4059 might_alloc include/linux/sched/mm.h:318 [inline] prepare_alloc_pages+0x15a/0x532 mm/page_alloc.c:4727 __alloc_frozen_pages_noprof+0x164/0x2124 mm/page_alloc.c:4948 __alloc_pages_noprof+0xe/0x22 mm/page_alloc.c:4993 __alloc_pages_node_noprof include/linux/gfp.h:284 [inline] alloc_pages_node_noprof include/linux/gfp.h:311 [inline] pcpu_alloc_pages mm/percpu-vm.c:95 [inline] pcpu_populate_chunk+0x272/0xf40 mm/percpu-vm.c:285 pcpu_alloc_noprof+0x93e/0x1d3e mm/percpu.c:1870 xt_percpu_counter_alloc+0x13a/0x194 net/netfilter/x_tables.c:1931 find_check_entry.constprop.0+0xe8/0x8e4 net/ipv6/netfilter/ip6_tables.c:545 translate_table+0xc28/0x15da net/ipv6/netfilter/ip6_tables.c:733 do_replace+0x2f8/0x44a net/ipv4/netfilter/ip_tables.c:1137 do_ip6t_set_ctl+0x39e/0x916 net/ipv6/netfilter/ip6_tables.c:1644 nf_setsockopt+0x78/0xda net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x13c/0x16e net/ipv6/ipv6_sockglue.c:998 tcp_setsockopt+0x8e/0xe0 net/ipv4/tcp.c:4108 sock_common_setsockopt+0x90/0xc0 net/core/sock.c:3944 do_sock_setsockopt+0x208/0x400 net/socket.c:2296 __sys_setsockopt+0x142/0x1e6 net/socket.c:2321 __do_sys_setsockopt net/socket.c:2327 [inline] __se_sys_setsockopt net/socket.c:2324 [inline] __riscv_sys_setsockopt+0xa6/0x114 net/socket.c:2324 syscall_handler+0x94/0x118 arch/riscv/include/asm/syscall.h:112 do_trap_ecall_u+0x396/0x530 arch/riscv/kernel/traps.c:341 handle_exception+0x146/0x152 arch/riscv/kernel/entry.S:197 -> #0 (pcpu_alloc_mutex){+.+.}-{4:4}: check_noncircular+0x132/0x146 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain kernel/locking/lockdep.c:3911 [inline] __lock_acquire+0x12b2/0x24ea kernel/locking/lockdep.c:5240 lock_acquire kernel/locking/lockdep.c:5871 [inline] lock_acquire+0x1ac/0x448 kernel/locking/lockdep.c:5828 __mutex_lock_common kernel/locking/mutex.c:602 [inline] __mutex_lock+0x166/0x1292 kernel/locking/mutex.c:747 _mutex_lock_killable+0x16/0x1e kernel/locking/mutex.c:815 pcpu_alloc_noprof+0xd64/0x1d3e mm/percpu.c:1782 init_alloc_hint lib/sbitmap.c:16 [inline] sbitmap_init_node+0x2ae/0x790 lib/sbitmap.c:126 sbitmap_queue_init_node+0x44/0x604 lib/sbitmap.c:438 bt_alloc block/blk-mq-tag.c:542 [inline] blk_mq_init_tags+0x126/0x290 block/blk-mq-tag.c:565 blk_mq_alloc_rq_map block/blk-mq.c:3538 [inline] blk_mq_alloc_map_and_rqs+0x1f4/0xea4 block/blk-mq.c:4094 __blk_mq_alloc_map_and_rqs block/blk-mq.c:4116 [inline] __blk_mq_alloc_map_and_rqs+0x11a/0x1c6 block/blk-mq.c:4107 blk_mq_realloc_tag_set_tags block/blk-mq.c:4755 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:4995 [inline] blk_mq_update_nr_hw_queues+0x41e/0xb86 block/blk-mq.c:5043 nbd_start_device+0x140/0xb2c drivers/block/nbd.c:1476 nbd_start_device_ioctl drivers/block/nbd.c:1527 [inline] __nbd_ioctl drivers/block/nbd.c:1602 [inline] nbd_ioctl+0x474/0xbde drivers/block/nbd.c:1642 blkdev_ioctl+0x25a/0xe38 block/ioctl.c:704 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __riscv_sys_ioctl+0x180/0x1e4 fs/ioctl.c:893 syscall_handler+0x94/0x118 arch/riscv/include/asm/syscall.h:112 do_trap_ecall_u+0x396/0x530 arch/riscv/kernel/traps.c:341 handle_exception+0x146/0x152 arch/riscv/kernel/entry.S:197 other info that might help us debug this: Chain exists of: pcpu_alloc_mutex --> fs_reclaim --> &q->q_usage_counter(io)#24 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->q_usage_counter(io)#24); lock(fs_reclaim); lock(&q->q_usage_counter(io)#24); lock(pcpu_alloc_mutex); *** DEADLOCK *** 5 locks held by syz.5.329/8699: #0: ffffaf801a2db230 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x144/0xbde drivers/block/nbd.c:1635 #1: ffffaf801a2db188 (&set->update_nr_hwq_lock){++++}-{4:4}, at: blk_mq_update_nr_hw_queues+0x3e/0xb86 block/blk-mq.c:5041 #2: ffffaf801a2db0d8 (&set->tag_list_lock){+.+.}-{4:4}, at: blk_mq_update_nr_hw_queues+0x52/0xb86 block/blk-mq.c:5042 #3: ffffaf8019f9e228 (&q->q_usage_counter(io)#24){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave block/blk-mq.c:205 [inline] #3: ffffaf8019f9e228 (&q->q_usage_counter(io)#24){++++}-{0:0}, at: __blk_mq_update_nr_hw_queues block/blk-mq.c:4993 [inline] #3: ffffaf8019f9e228 (&q->q_usage_counter(io)#24){++++}-{0:0}, at: blk_mq_update_nr_hw_queues+0x23a/0xb86 block/blk-mq.c:5043 #4: ffffaf8019f9e260 (&q->q_usage_counter(queue)#6){+.+.}-{0:0}, at: blk_mq_freeze_queue_nomemsave block/blk-mq.c:205 [inline] #4: ffffaf8019f9e260 (&q->q_usage_counter(queue)#6){+.+.}-{0:0}, at: __blk_mq_update_nr_hw_queues block/blk-mq.c:4993 [inline] #4: ffffaf8019f9e260 (&q->q_usage_counter(queue)#6){+.+.}-{0:0}, at: blk_mq_update_nr_hw_queues+0x23a/0xb86 block/blk-mq.c:5043 stack backtrace: CPU: 1 UID: 0 PID: 8699 Comm: syz.5.329 Not tainted 6.16.0-rc1-syzkaller-g19272b37aa4f #0 PREEMPT Hardware name: riscv-virtio,qemu (DT) Call Trace: [] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:132 [] show_stack+0x30/0x3c arch/riscv/kernel/stacktrace.c:138 [] __dump_stack lib/dump_stack.c:94 [inline] [] dump_stack_lvl+0x12e/0x1a6 lib/dump_stack.c:120 [] dump_stack+0x1c/0x24 lib/dump_stack.c:129 [] print_circular_bug+0x254/0x29a kernel/locking/lockdep.c:2046 [] check_noncircular+0x132/0x146 kernel/locking/lockdep.c:2178 [] check_prev_add kernel/locking/lockdep.c:3168 [inline] [] check_prevs_add kernel/locking/lockdep.c:3287 [inline] [] validate_chain kernel/locking/lockdep.c:3911 [inline] [] __lock_acquire+0x12b2/0x24ea kernel/locking/lockdep.c:5240 [] lock_acquire kernel/locking/lockdep.c:5871 [inline] [] lock_acquire+0x1ac/0x448 kernel/locking/lockdep.c:5828 [] __mutex_lock_common kernel/locking/mutex.c:602 [inline] [] __mutex_lock+0x166/0x1292 kernel/locking/mutex.c:747 [] _mutex_lock_killable+0x16/0x1e kernel/locking/mutex.c:815 [] pcpu_alloc_noprof+0xd64/0x1d3e mm/percpu.c:1782 [] init_alloc_hint lib/sbitmap.c:16 [inline] [] sbitmap_init_node+0x2ae/0x790 lib/sbitmap.c:126 [] sbitmap_queue_init_node+0x44/0x604 lib/sbitmap.c:438 [] bt_alloc block/blk-mq-tag.c:542 [inline] [] blk_mq_init_tags+0x126/0x290 block/blk-mq-tag.c:565 [] blk_mq_alloc_rq_map block/blk-mq.c:3538 [inline] [] blk_mq_alloc_map_and_rqs+0x1f4/0xea4 block/blk-mq.c:4094 [] __blk_mq_alloc_map_and_rqs block/blk-mq.c:4116 [inline] [] __blk_mq_alloc_map_and_rqs+0x11a/0x1c6 block/blk-mq.c:4107 [] blk_mq_realloc_tag_set_tags block/blk-mq.c:4755 [inline] [] __blk_mq_update_nr_hw_queues block/blk-mq.c:4995 [inline] [] blk_mq_update_nr_hw_queues+0x41e/0xb86 block/blk-mq.c:5043 [] nbd_start_device+0x140/0xb2c drivers/block/nbd.c:1476 [] nbd_start_device_ioctl drivers/block/nbd.c:1527 [inline] [] __nbd_ioctl drivers/block/nbd.c:1602 [inline] [] nbd_ioctl+0x474/0xbde drivers/block/nbd.c:1642 [] blkdev_ioctl+0x25a/0xe38 block/ioctl.c:704 [] vfs_ioctl fs/ioctl.c:51 [inline] [] __do_sys_ioctl fs/ioctl.c:907 [inline] [] __se_sys_ioctl fs/ioctl.c:893 [inline] [] __riscv_sys_ioctl+0x180/0x1e4 fs/ioctl.c:893 [] syscall_handler+0x94/0x118 arch/riscv/include/asm/syscall.h:112 [] do_trap_ecall_u+0x396/0x530 arch/riscv/kernel/traps.c:341 [] handle_exception+0x146/0x152 arch/riscv/kernel/entry.S:197