INFO: task syz-executor.3:27520 blocked for more than 143 seconds. Not tainted 5.15.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:26584 pid:27520 ppid: 18530 flags:0x00024006 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1857 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x174/0x270 kernel/sched/completion.c:138 io_wq_exit_workers fs/io-wq.c:1204 [inline] io_wq_put_and_exit+0x33a/0xb70 fs/io-wq.c:1239 io_uring_clean_tctx fs/io_uring.c:9774 [inline] io_uring_cancel_generic+0x61d/0x690 fs/io_uring.c:9855 io_uring_files_cancel include/linux/io_uring.h:16 [inline] do_exit+0x60c/0x2b40 kernel/exit.c:787 do_group_exit+0x125/0x310 kernel/exit.c:929 get_signal+0x47d/0x21d0 kernel/signal.c:2820 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f39c0a49ae9 RSP: 002b:00007f39bdfbf188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 0000000000000002 RBX: 00007f39c0b5cf60 RCX: 00007f39c0a49ae9 RDX: 0000000000000000 RSI: 00000000000002fc RDI: 0000000000000003 RBP: 00007f39c0aa3f25 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe036814ff R14: 00007f39bdfbf300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8b983a20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6461 1 lock held by in:imklog/6167: #0: ffff888072b6c0f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 2 locks held by agetty/15968: #0: ffff88801d110098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc90002bd32e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xc1d/0xf50 kernel/hung_task.c:295 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 32 Comm: ksmd Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:do_raw_spin_lock+0x1c4/0x2b0 kernel/locking/spinlock_debug.c:118 Code: ff df 4c 89 65 10 48 c7 04 03 00 00 00 00 48 8b 44 24 60 65 48 2b 04 25 28 00 00 00 0f 85 c7 00 00 00 48 83 c4 68 5b 5d 41 5c <41> 5d 41 5e c3 48 c7 c2 18 7c 7f 8b 89 44 24 28 48 b9 00 00 00 00 RSP: 0018:ffffc90000e7fbc8 EFLAGS: 00000292 RAX: 0000000000000000 RBX: ffff88802d7f4818 RCX: ffffffff815d4b30 RDX: 1ffff1100f59f23e RSI: 0000000000000004 RDI: ffffc90000e7fb70 RBP: ffff88808450cd68 R08: 0000000000000001 R09: 0000000000000003 R10: fffff520001cff6e R11: 0000000000000000 R12: ffffea0000b5fd00 R13: ffff88807acf91f0 R14: 0000000000000001 R15: ffff88807acf91e0 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe02ac0c000 CR3: 00000000733c4000 CR4: 0000000000350ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: spin_lock include/linux/spinlock.h:350 [inline] follow_page_pte+0x193/0xc60 mm/gup.c:491 follow_pmd_mask mm/gup.c:706 [inline] follow_pud_mask mm/gup.c:751 [inline] follow_p4d_mask mm/gup.c:777 [inline] follow_page_mask+0xb9e/0x1520 mm/gup.c:836 follow_page+0xb2/0x130 mm/gup.c:848 scan_get_next_rmap_item mm/ksm.c:2303 [inline] ksm_do_scan mm/ksm.c:2392 [inline] ksm_scan_thread+0xc0e/0x4a40 mm/ksm.c:2416 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: df 4c 89 65 fisttps 0x65(%rcx,%rcx,4) 4: 10 48 c7 adc %cl,-0x39(%rax) 7: 04 03 add $0x3,%al 9: 00 00 add %al,(%rax) b: 00 00 add %al,(%rax) d: 48 8b 44 24 60 mov 0x60(%rsp),%rax 12: 65 48 2b 04 25 28 00 sub %gs:0x28,%rax 19: 00 00 1b: 0f 85 c7 00 00 00 jne 0xe8 21: 48 83 c4 68 add $0x68,%rsp 25: 5b pop %rbx 26: 5d pop %rbp 27: 41 5c pop %r12 * 29: 41 5d pop %r13 <-- trapping instruction 2b: 41 5e pop %r14 2d: c3 retq 2e: 48 c7 c2 18 7c 7f 8b mov $0xffffffff8b7f7c18,%rdx 35: 89 44 24 28 mov %eax,0x28(%rsp) 39: 48 rex.W 3a: b9 00 00 00 00 mov $0x0,%ecx