INFO: task udevd:5858 blocked for more than 143 seconds. Not tainted 6.12.0-syzkaller-05480-gfcc79e1714e8 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:19768 pid:5858 tgid:5858 ppid:1 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 wait_for_reconnect drivers/block/nbd.c:1043 [inline] nbd_handle_cmd drivers/block/nbd.c:1085 [inline] nbd_queue_rq+0x7d9/0x2f30 drivers/block/nbd.c:1143 blk_mq_dispatch_rq_list+0xad3/0x19d0 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+0xb8a/0x1840 block/blk-mq-sched.c:309 blk_mq_sched_dispatch_requests+0xd6/0x190 block/blk-mq-sched.c:331 blk_mq_run_hw_queue+0x354/0x500 block/blk-mq.c:2354 blk_mq_flush_plug_list+0x118e/0x1870 block/blk-mq.c:2915 __blk_flush_plug+0x420/0x500 block/blk-core.c:1213 blk_finish_plug block/blk-core.c:1240 [inline] __submit_bio+0x46a/0x560 block/blk-core.c:637 __submit_bio_noacct_mq block/blk-core.c:710 [inline] submit_bio_noacct_nocheck+0x4d3/0xe30 block/blk-core.c:739 submit_bh fs/buffer.c:2825 [inline] block_read_full_folio+0x93b/0xcd0 fs/buffer.c:2452 filemap_read_folio+0x14b/0x630 mm/filemap.c:2367 do_read_cache_folio+0x3f5/0x850 mm/filemap.c:3827 read_mapping_folio include/linux/pagemap.h:1011 [inline] read_part_sector+0xb3/0x330 block/partitions/core.c:722 adfspart_check_ICS+0xd9/0x9a0 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+0x72c/0x13f0 block/partitions/core.c:693 blkdev_get_whole+0x2d2/0x450 block/bdev.c:707 bdev_open+0x2d4/0xc50 block/bdev.c:916 blkdev_open+0x389/0x4f0 block/fops.c:627 do_dentry_open+0x978/0x1460 fs/open.c:941 vfs_open+0x3e/0x330 fs/open.c:1071 do_open fs/namei.c:3828 [inline] path_openat+0x2c84/0x3590 fs/namei.c:3987 do_filp_open+0x27f/0x4e0 fs/namei.c:4014 do_sys_openat2+0x13e/0x1d0 fs/open.c:1398 do_sys_open fs/open.c:1413 [inline] __do_sys_openat fs/open.c:1429 [inline] __se_sys_openat fs/open.c:1424 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1424 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7d737169a4 RSP: 002b:00007ffdaa611bb0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00005569b13580c0 RCX: 00007f7d737169a4 RDX: 00000000000a0800 RSI: 00005569b1341cd0 RDI: 00000000ffffff9c RBP: 00005569b1341cd0 R08: 0000000000000001 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000a0800 R13: 00005569b1344320 R14: 0000000000000001 R15: 00005569b1323910 INFO: task udevd:5868 blocked for more than 144 seconds. Not tainted 6.12.0-syzkaller-05480-gfcc79e1714e8 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:20752 pid:5868 tgid:5868 ppid:1 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 wait_for_reconnect drivers/block/nbd.c:1043 [inline] nbd_handle_cmd drivers/block/nbd.c:1085 [inline] nbd_queue_rq+0x7d9/0x2f30 drivers/block/nbd.c:1143 blk_mq_dispatch_rq_list+0xad3/0x19d0 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+0xb8a/0x1840 block/blk-mq-sched.c:309 blk_mq_sched_dispatch_requests+0xd6/0x190 block/blk-mq-sched.c:331 blk_mq_run_hw_queue+0x354/0x500 block/blk-mq.c:2354 blk_mq_flush_plug_list+0x118e/0x1870 block/blk-mq.c:2915 __blk_flush_plug+0x420/0x500 block/blk-core.c:1213 blk_finish_plug block/blk-core.c:1240 [inline] __submit_bio+0x46a/0x560 block/blk-core.c:637 __submit_bio_noacct_mq block/blk-core.c:710 [inline] submit_bio_noacct_nocheck+0x4d3/0xe30 block/blk-core.c:739 submit_bh fs/buffer.c:2825 [inline] block_read_full_folio+0x93b/0xcd0 fs/buffer.c:2452 filemap_read_folio+0x14b/0x630 mm/filemap.c:2367 do_read_cache_folio+0x3f5/0x850 mm/filemap.c:3827 read_mapping_folio include/linux/pagemap.h:1011 [inline] read_part_sector+0xb3/0x330 block/partitions/core.c:722 adfspart_check_ICS+0xd9/0x9a0 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+0x72c/0x13f0 block/partitions/core.c:693 blkdev_get_whole+0x2d2/0x450 block/bdev.c:707 bdev_open+0x2d4/0xc50 block/bdev.c:916 blkdev_open+0x389/0x4f0 block/fops.c:627 do_dentry_open+0x978/0x1460 fs/open.c:941 vfs_open+0x3e/0x330 fs/open.c:1071 do_open fs/namei.c:3828 [inline] path_openat+0x2c84/0x3590 fs/namei.c:3987 do_filp_open+0x27f/0x4e0 fs/namei.c:4014 do_sys_openat2+0x13e/0x1d0 fs/open.c:1398 do_sys_open fs/open.c:1413 [inline] __do_sys_openat fs/open.c:1429 [inline] __se_sys_openat fs/open.c:1424 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1424 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7d737169a4 RSP: 002b:00007ffdaa611bb0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00005569b1343e80 RCX: 00007f7d737169a4 RDX: 00000000000a0800 RSI: 00005569b13242b0 RDI: 00000000ffffff9c RBP: 00005569b13242b0 R08: 0000000000000001 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000a0800 R13: 00005569b1344320 R14: 0000000000000001 R15: 00005569b1323910 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb3c860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 2 locks held by getty/5608: #0: ffff88814dab70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900033332f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by udevd/5848: #0: ffff888025d624c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904 #1: ffff88801ef5f790 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline] #1: ffff88801ef5f790 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline] #1: ffff88801ef5f790 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2354 #2: ffff888025de51f8 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xfe/0x2f30 drivers/block/nbd.c:1135 3 locks held by udevd/5858: #0: ffff888025c034c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904 #1: ffff888022f23f90 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline] #1: ffff888022f23f90 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline] #1: ffff888022f23f90 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2354 #2: ffff888025d851f8 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xfe/0x2f30 drivers/block/nbd.c:1135 3 locks held by udevd/5867: #0: ffff888025c3e4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904 #1: ffff888141fd9590 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline] #1: ffff888141fd9590 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline] #1: ffff888141fd9590 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2354 #2: ffff888025e07178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xfe/0x2f30 drivers/block/nbd.c:1135 3 locks held by udevd/5868: #0: ffff888025c394c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904 #1: ffff888141fd6690 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline] #1: ffff888141fd6690 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline] #1: ffff888141fd6690 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2354 #2: ffff888025d10178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xfe/0x2f30 drivers/block/nbd.c:1135 3 locks held by udevd/7872: #0: ffff888025d664c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904 #1: ffff88801ef5ff10 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline] #1: ffff88801ef5ff10 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline] #1: ffff88801ef5ff10 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2354 #2: ffff888025eb51f8 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xfe/0x2f30 drivers/block/nbd.c:1135 3 locks held by udevd/8007: #0: ffff888025c3a4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904 #1: ffff888141fd6e90 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline] #1: ffff888141fd6e90 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline] #1: ffff888141fd6e90 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2354 #2: ffff888025dae178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xfe/0x2f30 drivers/block/nbd.c:1135 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-syzkaller-05480-gfcc79e1714e8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5836 Comm: syz-executor Not tainted 6.12.0-syzkaller-05480-gfcc79e1714e8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:cr4_update_irqsoff+0x4f/0xb0 arch/x86/kernel/cpu/common.c:453 Code: 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 52 83 3d 95 fe 06 0f 00 74 16 65 8b 05 0c 1e ca 7e 85 c0 75 0b 65 8b 05 b9 1a ca 7e <85> c0 75 2d 48 f7 d3 4c 21 fb 4c 09 f3 4c 39 fb 75 0a 5b 41 5e 41 RSP: 0018:ffffc90003a1f8c0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000100 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000100 RDI: 0000000000000000 RBP: ffffc90003a1f9b0 R08: ffff88807e27b873 R09: 1ffff1100fc4f70e R10: dffffc0000000000 R11: ffffed100fc4f70f R12: 0000000000000014 R13: ffff88807e27b0c0 R14: 0000000000000000 R15: 00000000003526f0 FS: 000055557fbb2500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c39821d CR3: 000000007d9ce000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: switch_mm_irqs_off+0x7f3/0xa70 arch/x86/mm/tlb.c:653 context_switch kernel/sched/core.c:5353 [inline] __schedule+0x10c8/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 do_nanosleep+0x197/0x600 kernel/time/hrtimer.c:2079 hrtimer_nanosleep+0x1ec/0x410 kernel/time/hrtimer.c:2126 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1402 [inline] __se_sys_clock_nanosleep+0x32b/0x3c0 kernel/time/posix-timers.c:1379 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f65d73b28a3 Code: Unable to access opcode bytes at 0x7f65d73b2879. RSP: 002b:00007ffd6e67e688 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f65d73b28a3 RDX: 00007ffd6e67e6a0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 000000002eeb6af1 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffd6e67eae0 R13: 0000000000000004 R14: 00007ffd6e67e6dc R15: 00007ffd6e67e760