NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog NOHZ: local_softirq_pending 08 INFO: task syz-executor.3:30698 blocked for more than 140 seconds. Not tainted 4.14.194-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28912 30698 6378 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_timeout+0x80a/0xe90 kernel/time/timer.c:1731 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 ucma_close+0xfc/0x340 drivers/infiniband/core/ucma.c:1749 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164 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: 0033:0x416ec1 RSP: 002b:00007ffe431053d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000416ec1 RDX: 0000001b32020000 RSI: 000000000000086e RDI: 0000000000000003 RBP: 0000000000000001 R08: 00000000216a486e R09: 00000000216a4872 R10: 00007ffe431054c0 R11: 0000000000000293 R12: 00000000011905d0 R13: 0000000000055290 R14: ffffffffffffffff R15: 000000000118cf4c Showing all locks held in the system: 1 lock held by khungtaskd/1068: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 2 locks held by agetty/6285: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e3/0x1680 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1068 Comm: khungtaskd Not tainted 4.14.194-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x283 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x17f 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: 6067 Comm: rs:main Q:Reg Not tainted 4.14.194-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff888087558180 task.stack: ffff8880876a8000 RIP: 0010:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:67 RSP: 0018:ffff8880876af8c0 EFLAGS: 00000246 RAX: ffffed10107c9400 RBX: 0000000000001000 RCX: 0000000000000000 RDX: 0000000000000fe7 RSI: 0000000000000000 RDI: ffff888083e4a000 RBP: 0000000000000000 R08: 0000000000000001 R09: ffff888083e49019 R10: ffff888083e49fff R11: 0000000000000000 R12: 0000000000000019 R13: 000000000000010f R14: 0000000000000000 R15: 0000000000001000 FS: 00007fd7f5a95700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4259698000 CR3: 00000000a07ea000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: memset include/linux/string.h:357 [inline] zero_user_segments include/linux/highmem.h:203 [inline] __block_write_begin_int+0x8a3/0x1090 fs/buffer.c:2054 ext4_da_write_begin+0x402/0xe70 fs/ext4/inode.c:3108 generic_perform_write+0x1c9/0x420 mm/filemap.c:3047 __generic_file_write_iter+0x227/0x590 mm/filemap.c:3172 ext4_file_write_iter+0x276/0xd20 fs/ext4/file.c:270 call_write_iter include/linux/fs.h:1778 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x44c/0x630 fs/read_write.c:482 vfs_write+0x17f/0x4d0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xf2/0x210 fs/read_write.c:582 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fd7f84d91cd RSP: 002b:00007fd7f5a94590 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fd7ec024670 RCX: 00007fd7f84d91cd RDX: 0000000000000460 RSI: 00007fd7ec024670 RDI: 0000000000000008 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007fd7ec0243f0 R13: 00007fd7f5a945b0 R14: 00005570ab4a5440 R15: 0000000000000460 Code: e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3 aa <4c> 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01