BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580 in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 4318, name: udevd preempt_count: 0, expected: 0 RCU nest depth: 1, expected: 0 3 locks held by udevd/4318: #0: ffff0000f4c91240 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:774 [inline] #0: ffff0000f4c91240 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: blkdev_read_iter+0x390/0x4e0 block/fops.c:667 #1: ffff0000f4c913e0 (mapping.invalidate_lock){++++}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:819 [inline] #1: ffff0000f4c913e0 (mapping.invalidate_lock){++++}-{3:3}, at: page_cache_ra_unbounded+0xbc/0x53c mm/readahead.c:226 #2: ffff800015597440 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x18/0x54 include/linux/rcupdate.h:349 CPU: 1 PID: 4318 Comm: udevd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026 Call trace: dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106 dump_stack+0x1c/0x5c lib/dump_stack.c:113 __might_resched+0x354/0x4e0 kernel/sched/core.c:9970 __might_sleep+0x94/0x110 kernel/sched/core.c:9899 __mutex_lock_common+0xd0/0x1f3c kernel/locking/mutex.c:580 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 nvmet_subsys_nsid_exists+0xd0/0x150 drivers/nvme/target/configfs.c:632 nvmet_req_find_ns+0x308/0x3cc drivers/nvme/target/core.c:431 nvmet_parse_io_cmd drivers/nvme/target/core.c:903 [inline] nvmet_req_init+0x2bc/0xe58 drivers/nvme/target/core.c:976 nvme_loop_queue_rq+0x218/0x630 drivers/nvme/target/loop.c:151 __blk_mq_issue_directly block/blk-mq.c:2643 [inline] __blk_mq_try_issue_directly+0x3f8/0x63c block/blk-mq.c:2696 blk_mq_request_issue_directly block/blk-mq.c:2730 [inline] blk_mq_plug_issue_direct+0x22c/0x54c block/blk-mq.c:2750 blk_mq_flush_plug_list+0x5e4/0xa9c block/blk-mq.c:2851 __blk_flush_plug+0x358/0x3d8 block/blk-core.c:1179 blk_finish_plug+0x68/0x90 block/blk-core.c:1203 read_pages+0x4e8/0x68c mm/readahead.c:184 page_cache_ra_unbounded+0x458/0x53c mm/readahead.c:270 do_page_cache_ra mm/readahead.c:300 [inline] force_page_cache_ra mm/readahead.c:331 [inline] page_cache_sync_ra+0x318/0x3cc mm/readahead.c:713 page_cache_sync_readahead include/linux/pagemap.h:1250 [inline] filemap_get_pages mm/filemap.c:2665 [inline] filemap_read+0x4c4/0x20dc mm/filemap.c:2759 blkdev_read_iter+0x3a0/0x4e0 block/fops.c:668 call_read_iter include/linux/fs.h:2265 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x3cc/0x7b8 fs/read_write.c:470 ksys_read+0x12c/0x228 fs/read_write.c:613 __do_sys_read fs/read_write.c:623 [inline] __se_sys_read fs/read_write.c:621 [inline] __arm64_sys_read+0x7c/0x90 fs/read_write.c:621 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 ============================= [ BUG: Invalid wait context ] syzkaller #0 Tainted: G W ----------------------------- udevd/4318 is trying to lock: ffff800016b0bbb0 (&nvmet_configfs_subsystem.su_mutex){+.+.}-{3:3}, at: nvmet_subsys_nsid_exists+0xd0/0x150 drivers/nvme/target/configfs.c:632 other info that might help us debug this: context-{4:4} 3 locks held by udevd/4318: #0: ffff0000f4c91240 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:774 [inline] #0: ffff0000f4c91240 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: blkdev_read_iter+0x390/0x4e0 block/fops.c:667 #1: ffff0000f4c913e0 (mapping.invalidate_lock){++++}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:819 [inline] #1: ffff0000f4c913e0 (mapping.invalidate_lock){++++}-{3:3}, at: page_cache_ra_unbounded+0xbc/0x53c mm/readahead.c:226 #2: ffff800015597440 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x18/0x54 include/linux/rcupdate.h:349 stack backtrace: CPU: 1 PID: 4318 Comm: udevd Tainted: G W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026 Call trace: dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106 dump_stack+0x1c/0x5c lib/dump_stack.c:113 print_lock_invalid_wait_context kernel/locking/lockdep.c:4706 [inline] check_wait_context kernel/locking/lockdep.c:4776 [inline] __lock_acquire+0x17fc/0x6634 kernel/locking/lockdep.c:5013 lock_acquire+0x20c/0x638 kernel/locking/lockdep.c:5678 __mutex_lock_common+0x1a0/0x1f3c kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 nvmet_subsys_nsid_exists+0xd0/0x150 drivers/nvme/target/configfs.c:632 nvmet_req_find_ns+0x308/0x3cc drivers/nvme/target/core.c:431 nvmet_parse_io_cmd drivers/nvme/target/core.c:903 [inline] nvmet_req_init+0x2bc/0xe58 drivers/nvme/target/core.c:976 nvme_loop_queue_rq+0x218/0x630 drivers/nvme/target/loop.c:151 __blk_mq_issue_directly block/blk-mq.c:2643 [inline] __blk_mq_try_issue_directly+0x3f8/0x63c block/blk-mq.c:2696 blk_mq_request_issue_directly block/blk-mq.c:2730 [inline] blk_mq_plug_issue_direct+0x22c/0x54c block/blk-mq.c:2750 blk_mq_flush_plug_list+0x5e4/0xa9c block/blk-mq.c:2851 __blk_flush_plug+0x358/0x3d8 block/blk-core.c:1179 blk_finish_plug+0x68/0x90 block/blk-core.c:1203 read_pages+0x4e8/0x68c mm/readahead.c:184 page_cache_ra_unbounded+0x458/0x53c mm/readahead.c:270 do_page_cache_ra mm/readahead.c:300 [inline] force_page_cache_ra mm/readahead.c:331 [inline] page_cache_sync_ra+0x318/0x3cc mm/readahead.c:713 page_cache_sync_readahead include/linux/pagemap.h:1250 [inline] filemap_get_pages mm/filemap.c:2665 [inline] filemap_read+0x4c4/0x20dc mm/filemap.c:2759 blkdev_read_iter+0x3a0/0x4e0 block/fops.c:668 call_read_iter include/linux/fs.h:2265 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x3cc/0x7b8 fs/read_write.c:470 ksys_read+0x12c/0x228 fs/read_write.c:613 __do_sys_read fs/read_write.c:623 [inline] __se_sys_read fs/read_write.c:621 [inline] __arm64_sys_read+0x7c/0x90 fs/read_write.c:621 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 nvme1c1n1: I/O Cmd(0x2) @ LBA 4080, 1 blocks, I/O Error (sct 0x3 / sc 0x0) MORE I/O error, dev nvme1c1n1, sector 32640 op 0x0:(READ) flags 0x4080700 phys_seg 1 prio class 2