INFO: task syz-executor5:5863 blocked for more than 120 seconds. Not tainted 4.4.105-gdcfa5fe #7 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor5 D ffff8801cda8f7c8 29304 5863 3542 0x00000004 ffff8801cda8f7c8 dffffc0000000000 ffff8800b2f69ff0 ffff8801cda8f7a8 ffffffff812284ff ffff8800b2f69f00 ffff8801db51f878 ffff8801db51f8a0 ffff8801db51ef98 ffff8800b2fb5e00 ffff8800b2f69780 ffff8801cda88000 Call Trace: [] schedule+0x9a/0x1c0 kernel/sched/core.c:3351 [] rwsem_down_read_failed+0x1bf/0x300 kernel/locking/rwsem-xadd.c:250 [] call_rwsem_down_read_failed+0x14/0x30 arch/x86/lib/rwsem.S:90 [] set_termios+0xe2/0x570 drivers/tty/tty_ioctl.c:599 [] tty_mode_ioctl+0x7ce/0x8b0 drivers/tty/tty_ioctl.c:977 [] n_tty_ioctl_helper+0x28/0x320 drivers/tty/tty_ioctl.c:1168 [] n_tty_ioctl+0x12c/0x2c0 drivers/tty/n_tty.c:2503 [] tty_ioctl+0x675/0x1fa0 drivers/tty/tty_io.c:2980 [] vfs_ioctl fs/ioctl.c:43 [inline] [] do_vfs_ioctl+0x681/0xe10 fs/ioctl.c:607 [] SYSC_ioctl fs/ioctl.c:622 [inline] [] SyS_ioctl+0x74/0x80 fs/ioctl.c:613 [] entry_SYSCALL_64_fastpath+0x16/0x76 2 locks held by syz-executor5/5863: #0: (&tty->ldisc_sem){++++++}, at: [] tty_ldisc_ref_wait+0x1d/0xa0 drivers/tty/tty_ldisc.c:264 #1: (&o_tty->termios_rwsem/1){++++.+}, at: [] set_termios+0xe2/0x570 drivers/tty/tty_ioctl.c:599 Sending NMI to all CPUs: NMI backtrace for cpu 0 CPU: 0 PID: 483 Comm: khungtaskd Not tainted 4.4.105-gdcfa5fe #7 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8800bb188000 task.stack: ffff8800bb3b8000 RIP: 0010:[] [] native_apic_mem_write arch/x86/include/asm/apic.h:94 [inline] RIP: 0010:[] [] __default_send_IPI_dest_field arch/x86/include/asm/ipi.h:119 [inline] RIP: 0010:[] [] _flat_send_IPI_mask arch/x86/kernel/apic/apic_flat_64.c:61 [inline] RIP: 0010:[] [] flat_send_IPI_mask+0xf7/0x1a0 arch/x86/kernel/apic/apic_flat_64.c:69 RSP: 0018:ffff8800bb3bfcb8 EFLAGS: 00000046 RAX: 0000000003000000 RBX: 0000000000000c00 RCX: 0000000000000000 RDX: 0000000000000c00 RSI: 0000000000000000 RDI: ffffffffff5fb300 RBP: ffff8800bb3bfce0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000246 R13: 0000000000000003 R14: ffffffff8426aba0 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8801db400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000041b1c0 CR3: 00000001d70c3000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffffffff8426aba0 ffffffff847e7480 ffffffff847e4a24 0000000000000001 dffffc0000000000 ffff8800bb3bfd00 ffffffff810b4ecb fffffbfff08fc944 00000000000194a0 ffff8800bb3bfd68 ffffffff81cd3418 ffff8800bb3bfd28 Call Trace: [] nmi_raise_cpu_backtrace+0x5b/0x70 arch/x86/kernel/apic/hw_nmi.c:33 [] nmi_trigger_all_cpu_backtrace+0x428/0x590 lib/nmi_backtrace.c:85 [] arch_trigger_all_cpu_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 [] trigger_all_cpu_backtrace include/linux/nmi.h:44 [inline] [] check_hung_task kernel/hung_task.c:125 [inline] [] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline] [] watchdog+0x636/0xa20 kernel/hung_task.c:238 [] kthread+0x245/0x310 kernel/kthread.c:211 [] ret_from_fork+0x3f/0x70 arch/x86/entry/entry_64.S:468 Code: b3 5f ff f6 c4 10 75 e1 44 89 e8 c1 e0 18 89 04 25 10 b3 5f ff 44 89 fa 09 da 80 cf 04 41 83 ff 02 0f 44 d3 89 14 25 00 b3 5f ff <41> f7 c4 00 02 00 00 74 1a e8 3b 97 16 00 4c 89 e7 57 9d 0f 1f NMI backtrace for cpu 1 CPU: 1 PID: 3157 Comm: rsyslogd Not tainted 4.4.105-gdcfa5fe #7 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8800b6ff4680 task.stack: ffff8801d9da0000 RIP: 0010:[] [] preempt_count_sub+0x38/0x160 kernel/sched/core.c:3093 RSP: 0018:ffff8801d9da7798 EFLAGS: 00000297 RAX: 0000000000000003 RBX: 0000000000000001 RCX: 0000000000000001 RDX: 0000000000000004 RSI: ffffffff81034666 RDI: ffffffff856d5680 RBP: ffff8801d9da77a0 R08: ffff8801d9da78d8 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d9da78c8 R13: ffffffffffff8000 R14: ffff8801d9da78c0 R15: 00000000024000c0 FS: 00007ff42bf80700(0000) GS:ffff8801db500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020985ffc CR3: 00000001d70c3000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: 0000000002400000 ffff8801d9da77b8 ffffffff812e243a 00000000024000c0 ffff8801d9da77d0 ffffffff8117f7eb 0000000000000000 ffff8801d9da7828 ffffffff81016a08 ffff8801d9da0000 ffff8801d9da78c8 ffff8801d9da78d8 Call Trace: [] is_module_text_address+0x2a/0x50 kernel/module.c:4078 [] __kernel_text_address+0x6b/0xa0 kernel/extable.c:103 [] print_context_stack+0x48/0xc0 arch/x86/kernel/dumpstack.c:107 [] dump_trace+0x142/0x350 arch/x86/kernel/dumpstack_64.c:243 [] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63 [] save_stack+0x43/0xd0 mm/kasan/kasan.c:512 [] set_track mm/kasan/kasan.c:524 [inline] [] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:616 [] kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:554 [] slab_post_alloc_hook mm/slub.c:1349 [inline] [] slab_alloc_node mm/slub.c:2615 [inline] [] slab_alloc mm/slub.c:2623 [inline] [] kmem_cache_alloc_trace+0xbe/0x2b0 mm/slub.c:2640 [] kmalloc include/linux/slab.h:476 [inline] [] syslog_print kernel/printk/printk.c:1148 [inline] [] do_syslog+0x52a/0xb00 kernel/printk/printk.c:1331 [] kmsg_read+0x65/0x80 fs/proc/kmsg.c:39 [] proc_reg_read+0xbc/0x180 fs/proc/inode.c:202 [] __vfs_read+0xda/0x3e0 fs/read_write.c:432 [] vfs_read+0xe1/0x340 fs/read_write.c:454 [] SYSC_read fs/read_write.c:569 [inline] [] SyS_read+0xd3/0x1c0 fs/read_write.c:562 [] entry_SYSCALL_64_fastpath+0x16/0x76 Code: e5 53 89 fb 48 c7 c7 80 56 6d 85 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 02 01 00 00 <8b> 0d 62 db 53 04 85 c9 75 1b 65 8b 05 67 c3 e7 7e 89 c2 81 e2