INFO: task syz.7.24:6671 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.24 state:D stack:28184 pid:6671 tgid:6669 ppid:6640 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x15dd/0x52d0 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0x164/0x360 kernel/sched/core.c:7008 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 blk_debugfs_lock_nomemsave block/blk.h:740 [inline] blk_trace_remove kernel/trace/blktrace.c:561 [inline] blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952 blkdev_common_ioctl+0x13a7/0x3250 block/ioctl.c:724 blkdev_ioctl+0x528/0x740 block/ioctl.c:798 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f67ceb9c819 RSP: 002b:00007f67cfa26028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f67cee16090 RCX: 00007f67ceb9c819 RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003 RBP: 00007f67cec32c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f67cee16128 R14: 00007f67cee16090 R15: 00007ffd9a881118 Showing all locks held in the system: 1 lock held by ksoftirqd/0/15: 1 lock held by khungtaskd/31: #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5585: #0: ffff888036be30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 3 locks held by syz.7.24/6670: 1 lock held by syz.7.24/6671: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952 1 lock held by syz.8.25/6718: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788 1 lock held by syz.8.25/6719: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952 1 lock held by syz.9.26/6859: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788 1 lock held by syz.9.26/6860: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952 1 lock held by syz.0.27/6978: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788 1 lock held by syz.0.27/6980: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952 1 lock held by syz.1.28/7246: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788 1 lock held by syz.1.28/7247: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952 1 lock held by syz.2.29/7467: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788 1 lock held by syz.2.29/7469: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952 1 lock held by syz.3.30/7704: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788 1 lock held by syz.3.30/7706: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952 1 lock held by syz.4.31/7966: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788 1 lock held by syz.4.31/7967: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952 1 lock held by syz.5.32/8240: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788 1 lock held by syz.5.32/8243: #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline] #0: ffff888026442578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952 1 lock held by rm/8316: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8317 Comm: rm Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:check_wait_context kernel/locking/lockdep.c:-1 [inline] RIP: 0010:__lock_acquire+0x4a7/0x2cf0 kernel/locking/lockdep.c:5187 Code: ce 78 0b 00 00 31 c1 ff cb 49 ff cc f7 c1 00 60 00 00 74 cf eb 17 48 c7 c7 70 c9 62 8e 4c 89 fe e8 6e 63 4a 03 8b 45 20 eb cf <44> 89 eb 65 8b 05 fb 6d 7b 11 85 c0 0f 84 f3 00 00 00 41 b4 03 41 RSP: 0018:ffffc900035473d0 EFLAGS: 00000086 RAX: 0000000000020007 RBX: 0000000000000001 RCX: 00000000ffffffff RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888030c38bd0 R08: ffffffff823c3e74 R09: ffffffff8e75e5e0 R10: dffffc0000000000 R11: fffff940005ff9d9 R12: ffffffffffffffff R13: 0000000000000000 R14: ffff888030c38000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125454000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1af9c42e9c CR3: 00000001a7cfa000 CR4: 00000000003526f0 Call Trace: lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] page_table_check_clear+0x164/0x5f0 mm/page_table_check.c:77 ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline] get_and_clear_full_ptes include/linux/pgtable.h:846 [inline] zap_present_folio_ptes mm/memory.c:1643 [inline] zap_present_ptes mm/memory.c:1725 [inline] do_zap_pte_range mm/memory.c:1827 [inline] zap_pte_range mm/memory.c:1929 [inline] zap_pmd_range mm/memory.c:2021 [inline] zap_pud_range mm/memory.c:2049 [inline] zap_p4d_range mm/memory.c:2070 [inline] unmap_page_range+0x33b3/0x48f0 mm/memory.c:2091 unmap_single_vma mm/memory.c:2133 [inline] unmap_vmas+0x48f/0x6a0 mm/memory.c:2171 exit_mmap+0x280/0xa10 mm/mmap.c:1302 __mmput+0x118/0x430 kernel/fork.c:1175 exit_mm+0x168/0x220 kernel/exit.c:581 do_exit+0x6a2/0x23c0 kernel/exit.c:964 do_group_exit+0x21b/0x2d0 kernel/exit.c:1118 __do_sys_exit_group kernel/exit.c:1129 [inline] __se_sys_exit_group kernel/exit.c:1127 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1127 x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1af9da16c5 Code: Unable to access opcode bytes at 0x7f1af9da169b. RSP: 002b:00007ffdf33ad628 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f1af9ea2fe8 RCX: 00007f1af9da16c5 RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000 RBP: 0000000000000001 R08: 00007ffdf33ad5b8 R09: 0000000000000000 R10: 00007ffdf33ad450 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1af9ea1680 R15: 00007f1af9ea3000