INFO: task syz.1.3811:19524 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.1.3811 state:D stack:27784 pid:19524 tgid:19523 ppid:17138 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x125c/0x6730 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7322 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7379 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0xccc/0x1bd0 kernel/locking/mutex.c:821 bdev_open+0x41a/0xe40 block/bdev.c:948 blkdev_open+0x34e/0x4f0 block/fops.c:672 do_dentry_open+0x6ab/0x14d0 fs/open.c:947 vfs_open+0x82/0x3f0 fs/open.c:1079 do_open fs/namei.c:4700 [inline] path_openat+0x2873/0x4280 fs/namei.c:4859 do_file_open+0x20e/0x430 fs/namei.c:4888 do_sys_openat2+0x10f/0x1e0 fs/open.c:1395 do_sys_open fs/open.c:1401 [inline] __do_sys_openat fs/open.c:1417 [inline] __se_sys_openat fs/open.c:1412 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1412 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f098c35d68e RSP: 002b:00007f098d21cb28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f098d21d6c0 RCX: 00007f098c35d68e RDX: 0000000000000200 RSI: 00007f098d21cc00 RDI: ffffffffffffff9c RBP: 00007f098d21cc00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd R13: 00007f098c616038 R14: 00007f098c615fa0 R15: 00007fff7f3ec6f8 INFO: lockdep is turned off. NMI backtrace for cpu 1 CPU: 1 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 05/09/2026 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:162 [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:353 [inline] watchdog+0xcb1/0x1030 kernel/hung_task.c:561 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 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: 23145 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:1144 [inline] RIP: 0010:debug_check_no_obj_freed+0x2dd/0x630 lib/debugobjects.c:1184 Code: 00 00 ad de 49 89 56 08 48 89 c7 48 89 30 48 83 c6 22 48 89 70 08 e8 92 c3 ff ff 4c 89 f0 48 89 c2 48 c1 ea 03 42 80 3c 22 00 <0f> 84 23 ff ff ff 48 89 c7 48 89 44 24 10 e8 90 c5 70 fd 48 8b 44 RSP: 0018:ffffc900001f7860 EFLAGS: 00000046 RAX: ffff88805653c1c0 RBX: 0000000000000014 RCX: ffffffff81e54168 RDX: 1ffff1100aca7838 RSI: 0000000000000000 RDI: ffff888055dd5600 RBP: ffffc900001f7988 R08: 0000000000000001 R09: fffff5200003eefa R10: 0000000000000003 R11: 0000000000000001 R12: dffffc0000000000 R13: ffffc90029411000 R14: ffff88805653c1c0 R15: ffffc90029811000 FS: 0000000000000000(0000) GS:ffff88812431a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056325a9daa78 CR3: 00000000760b7000 CR4: 00000000003526f0 Call Trace: remove_vm_area+0x1b0/0x390 mm/vmalloc.c:3330 vfree mm/vmalloc.c:3478 [inline] vfree+0x6d/0x750 mm/vmalloc.c:3462 kcov_put kernel/kcov.c:442 [inline] kcov_put kernel/kcov.c:438 [inline] kcov_close+0x34/0x60 kernel/kcov.c:543 __fput+0x3ff/0xb50 fs/file_table.c:512 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x951/0x2ae0 kernel/exit.c:1004 do_group_exit+0xd5/0x2a0 kernel/exit.c:1147 get_signal+0x1ec7/0x21e0 kernel/signal.c:3038 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x139/0x6f0 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f872f79caeb Code: Unable to access opcode bytes at 0x7f872f79cac1. RSP: 002b:00007ffc84abe520 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffed RBX: 0000000000000005 RCX: 00007f872f79caeb RDX: 00007ffc84abe580 RSI: 0000000000008933 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000004 R10: 0000000000000004 R11: 0000000000000246 R12: 00007ffc84abe60c R13: 00007f872f83347e R14: 00007f8730544620 R15: 00007f872f83347e