INFO: task syz.0.5355:27893 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.5355 state:D stack:26760 pid:27893 tgid:27892 ppid:16982 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0xfee/0x6020 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 bdev_open+0xa2/0xe40 block/bdev.c:961 bdev_file_open_by_dev block/bdev.c:1075 [inline] bdev_file_open_by_dev+0x179/0x210 block/bdev.c:1050 setup_bdev_super+0x385/0x730 fs/super.c:1612 get_tree_bdev_flags+0x363/0x620 fs/super.c:1692 vfs_get_tree+0x92/0x320 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3760 [inline] do_new_mount fs/namespace.c:3836 [inline] path_mount+0x7d0/0x23d0 fs/namespace.c:4146 do_mount fs/namespace.c:4159 [inline] __do_sys_mount fs/namespace.c:4348 [inline] __se_sys_mount fs/namespace.c:4325 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:4325 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7d0b79bf79 RSP: 002b:00007f7d0c634028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f7d0ba15fa0 RCX: 00007f7d0b79bf79 RDX: 0000200000000080 RSI: 0000200000000040 RDI: 0000200000000000 RBP: 00007f7d0b8327e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000001a0c000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7d0ba16038 R14: 00007f7d0ba15fa0 R15: 00007ffe1abd3768 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e7e7620 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e7e7620 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e7e7620 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by getty/5562: #0: ffff888038f410a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211 1 lock held by udevd/5790: #0: ffff888027278358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:961 1 lock held by udevd/6060: #0: ffff88802727e358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:961 2 locks held by syz.0.5355/27893: #0: ffff888046e9a0e0 (&type->s_umount_key#102/1){+.+.}-{4:4}, at: alloc_super+0x244/0xd20 fs/super.c:345 #1: ffff888027278358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xa2/0xe40 block/bdev.c:961 2 locks held by syz.5.5753/30703: #0: ffff888077699ec8 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline] #0: ffff888077699ec8 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x260 net/socket.c:661 #1: ffffffff8e7f3238 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xcc3/0xfe0 kernel/hung_task.c:515 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30716 Comm: rm Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:write_comp_data+0x40/0x90 kernel/kcov.c:246 Code: 02 12 a9 00 01 ff 00 74 1b f6 c4 01 74 07 a9 00 00 ff 00 74 05 e9 80 bd 7c 09 8b 87 54 16 00 00 85 c0 74 f1 8b 87 30 16 00 00 <83> f8 03 75 e6 48 8b 87 38 16 00 00 8b bf 34 16 00 00 48 8b 30 48 RSP: 0000:ffffc9000b77f9f8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000009 RCX: ffffffff8240e038 RDX: 0000000000000009 RSI: 000000000000003f RDI: ffff888040df8000 RBP: ffffc9000b77fb70 R08: 0000000000000001 R09: 000000000000003f R10: 0000000000000009 R11: 0000000000000000 R12: 0000000000000009 R13: ffff88814890a100 R14: dffffc0000000000 R15: 000000000000000f FS: 0000000000000000(0000) GS:ffff88812448b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9a44672200 CR3: 00000000703e6000 CR4: 00000000003526f0 DR0: 0000000000000070 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: xas_next_entry include/linux/xarray.h:1729 [inline] next_uptodate_folio+0x188/0xd00 mm/filemap.c:3699 filemap_map_pages+0x82c/0x2110 mm/filemap.c:3929 do_fault_around mm/memory.c:5748 [inline] do_read_fault mm/memory.c:5781 [inline] do_fault+0x9e5/0x1a00 mm/memory.c:5924 do_pte_missing mm/memory.c:4469 [inline] handle_pte_fault mm/memory.c:6308 [inline] __handle_mm_fault+0x180f/0x2b60 mm/memory.c:6446 handle_mm_fault+0x36d/0xa20 mm/memory.c:6615 do_user_addr_fault+0x5a3/0x12f0 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f9a44745652 Code: 0f 1f 84 00 00 00 00 00 3d 53 e5 74 64 75 0e 48 89 da 44 89 e6 4c 89 ef e8 5b f2 ff ff 49 3b 9d e0 02 00 00 0f 84 8e 01 00 00 <8b> 43 c8 48 83 eb 38 83 f8 04 75 d2 48 8b 53 10 49 8b 45 00 4c 8b RSP: 002b:00007ffedc8966d0 EFLAGS: 00010293 RAX: 000000000000003f RBX: 00007f9a44672238 RCX: 0000000000000009 RDX: 00007f9a44672040 RSI: 0000000000000006 RDI: 000000006fffffff RBP: 00007ffedc896820 R08: 0000000000000006 R09: 00000000effffef5 R10: 0000000070000029 R11: 00007ffedc896908 R12: 0000000000000003 R13: 00007f9a447340c0 R14: 00007ffedc8968c0 R15: 00007f9a44733918