INFO: task syz-executor.5:12356 blocked for more than 140 seconds. Not tainted 4.14.295-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28720 12356 8006 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_timeout+0x80a/0xe90 kernel/time/timer.c:1724 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common+0x272/0x430 kernel/sched/completion.c:123 usb_start_wait_urb+0x125/0x440 drivers/usb/core/message.c:61 usb_bulk_msg+0x1f6/0x500 drivers/usb/core/message.c:252 proc_bulk+0x331/0x6d0 drivers/usb/core/devio.c:1223 usbdev_do_ioctl+0x5b0/0x2b70 drivers/usb/core/devio.c:2449 usbdev_ioctl+0x21/0x30 drivers/usb/core/devio.c:2599 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f48f021b5a9 RSP: 002b:00007f48eeb8e168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f48f033bf80 RCX: 00007f48f021b5a9 RDX: 0000000020000000 RSI: 00000000c0185502 RDI: 0000000000000003 RBP: 00007f48f0276580 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc27764d2f R14: 00007f48eeb8e300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1533: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1533 Comm: khungtaskd Not tainted 4.14.295-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 15706 Comm: syz-executor.4 Not tainted 4.14.295-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 task: ffff8880b08fc380 task.stack: ffff888092378000 RIP: 0010:compound_head include/linux/page-flags.h:151 [inline] RIP: 0010:PageSwapCache include/linux/page-flags.h:331 [inline] RIP: 0010:free_swap_cache mm/swap_state.c:294 [inline] RIP: 0010:free_pages_and_swap_cache+0x7d/0x210 mm/swap_state.c:322 RSP: 0018:ffff88809237f738 EFLAGS: 00000246 RAX: 1ffffd4000466a1c RBX: ffff88809fe89cf8 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea00023350a0 RBP: ffffea0002335080 R08: ffff8880a157e640 R09: 0000000000000000 R10: 0000000000000000 R11: ffff8880b08fc380 R12: dffffc0000000000 R13: ffffea00023350c0 R14: ffffea00023350e0 R15: dead000000000100 FS: 00007f6d58f2e700(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555701b708 CR3: 00000000aaf0f000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tlb_flush_mmu_free+0xc1/0x1a0 mm/memory.c:272 zap_pte_range mm/memory.c:1444 [inline] zap_pmd_range mm/memory.c:1479 [inline] zap_pud_range mm/memory.c:1508 [inline] zap_p4d_range mm/memory.c:1529 [inline] unmap_page_range+0x1558/0x1d90 mm/memory.c:1550 unmap_single_vma+0x147/0x2b0 mm/memory.c:1595 unmap_vmas+0x9d/0x160 mm/memory.c:1625 exit_mmap+0x270/0x4d0 mm/mmap.c:3078 __mmput kernel/fork.c:931 [inline] mmput kernel/fork.c:952 [inline] mmput+0xfa/0x420 kernel/fork.c:947 exit_mm kernel/exit.c:548 [inline] do_exit+0x984/0x2850 kernel/exit.c:855 do_group_exit+0x100/0x2e0 kernel/exit.c:965 get_signal+0x38d/0x1ca0 kernel/signal.c:2412 do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:792 exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f6d5a61e5a9 RSP: 002b:00007f6d58f2e218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f6d5a73f1f8 RCX: 00007f6d5a61e5a9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f6d5a73f1f8 RBP: 00007f6d5a73f1f0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6d5a73f1fc R13: 00007fff9dc45a9f R14: 00007f6d58f2e300 R15: 0000000000022000 Code: c1 e8 03 42 80 3c 20 00 0f 85 58 01 00 00 4c 8b 2b 4d 8d 75 20 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 0f 85 63 01 00 00 4d 8b 7d 20 <4c> 89 ed 41 f6 c7 01 0f 85 12 01 00 00 e8 b1 8e db ff 48 8d 7d