INFO: rcu_preempt self-detected stall on CPU
	1-...: (10499 ticks this GP) idle=1b2/140000000000001/0 softirq=163466/163468 fqs=5156 
	 (t=10500 jiffies g=53279 c=53278 q=3553)
NMI backtrace for cpu 1
CPU: 1 PID: 9729 Comm: syz-executor2 Not tainted 4.14.77+ #21
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x11b lib/dump_stack.c:53
 nmi_cpu_backtrace.cold.0+0x47/0x85 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x121/0x146 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:156 [inline]
 rcu_dump_cpu_stacks+0x171/0x1bf kernel/rcu/tree.c:1396
 print_cpu_stall kernel/rcu/tree.c:1542 [inline]
 check_cpu_stall kernel/rcu/tree.c:1610 [inline]
 __rcu_pending kernel/rcu/tree.c:3373 [inline]
 rcu_pending kernel/rcu/tree.c:3435 [inline]
 rcu_check_callbacks.cold.56+0x478/0xd99 kernel/rcu/tree.c:2775
 update_process_times+0x24/0x60 kernel/time/timer.c:1588
 tick_sched_handle.isra.8+0x73/0x150 kernel/time/tick-sched.c:161
 tick_sched_timer+0x7e/0x160 kernel/time/tick-sched.c:1321
 __run_hrtimer kernel/time/hrtimer.c:1259 [inline]
 __hrtimer_run_queues+0x2d0/0xc10 kernel/time/hrtimer.c:1323
 hrtimer_interrupt+0x19a/0x440 kernel/time/hrtimer.c:1357
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline]
 smp_apic_timer_interrupt+0x13a/0x5f0 arch/x86/kernel/apic/apic.c:1062
 apic_timer_interrupt+0x84/0x90 arch/x86/entry/entry_64.S:787
 </IRQ>
RIP: 0010:__sanitizer_cov_trace_pc+0x48/0x60 kernel/kcov.c:88
RSP: 0000:ffff8801d44e72e8 EFLAGS: 00000283 ORIG_RAX: ffffffffffffff10
RAX: 0000000000040000 RBX: ffff8801d44e75f8 RCX: 0000000000000001
RDX: ffffffff813e62a7 RSI: ffffc900023a8000 RDI: 0000000000000001
RBP: ffff8801bdc5aa80 R08: 0000000000000010 R09: 000000001087966c
R10: ffffed0043fffa09 R11: 000001a62146f7a6 R12: ffffffff9bb1cc80
R13: 0000000000000008 R14: ffff8801d44e73c8 R15: dffffc0000000000
 __read_once_size include/linux/compiler.h:183 [inline]
 atomic64_read arch/x86/include/asm/atomic64_64.h:22 [inline]
 atomic_long_read include/asm-generic/atomic-long.h:45 [inline]
 perf_event_count kernel/events/core.c:3720 [inline]
 perf_output_read_group kernel/events/core.c:5872 [inline]
 perf_output_read+0x547/0xfb0 kernel/events/core.c:5909
 perf_output_sample+0x10dd/0x1780 kernel/events/core.c:5951
 __perf_event_output kernel/events/core.c:6261 [inline]
 perf_event_output_forward+0x121/0x230 kernel/events/core.c:6274
 __perf_event_overflow+0x116/0x320 kernel/events/core.c:7510
 perf_swevent_overflow+0x166/0x1f0 kernel/events/core.c:7586
 perf_swevent_event+0x19c/0x270 kernel/events/core.c:7619
 do_perf_sw_event kernel/events/core.c:7727 [inline]
 ___perf_sw_event+0x296/0x480 kernel/events/core.c:7758
 __perf_sw_event+0x3f/0x70 kernel/events/core.c:7770
 perf_sw_event include/linux/perf_event.h:1041 [inline]
 __do_page_fault+0x77f/0xb60 arch/x86/mm/fault.c:1466
 page_fault+0x22/0x50 arch/x86/entry/entry_64.S:1104
RIP: 0010:copy_user_enhanced_fast_string+0x7/0x10 arch/x86/lib/copy_user_64.S:180
RSP: 0000:ffff8801d44e7b98 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000001000 RCX: 00000000000001c0
RDX: 0000000000001000 RSI: 0000000020ca0000 RDI: ffff8801cca4fe40
RBP: 0000000020c9f1c0 R08: 0000000000000000 R09: 0000000000000040
R10: ffffed0039949fff R11: ffff8801cca4ffff R12: ffff8801cca4f000
R13: 00007ffffffff000 R14: 0000000020ca01c0 R15: ffff8801cca4f000
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:55 [inline]
 copyin+0x99/0xc0 lib/iov_iter.c:146
 copy_page_from_iter_iovec lib/iov_iter.c:290 [inline]
 copy_page_from_iter+0x320/0x7a0 lib/iov_iter.c:731
 pipe_write+0x21a/0xd30 fs/pipe.c:434
 call_write_iter include/linux/fs.h:1782 [inline]
 new_sync_write fs/read_write.c:471 [inline]
 __vfs_write+0x417/0x5c0 fs/read_write.c:484
 vfs_write+0x17f/0x4d0 fs/read_write.c:546
 SYSC_write fs/read_write.c:593 [inline]
 SyS_write+0xc2/0x1a0 fs/read_write.c:585
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x457569
RSP: 002b:00007f95b5e23c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 00000000fffffef3 RSI: 00000000200001c0 RDI: 0000000000000007
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f95b5e246d4
R13: 00000000004c2883 R14: 00000000004d8568 R15: 00000000ffffffff
INFO: rcu_sched self-detected stall on CPU
	1-...: (10487 ticks this GP) idle=1b2/140000000000001/0 softirq=163468/163468 fqs=5151 
INFO: rcu_sched detected stalls on CPUs/tasks:
	1-...: (10487 ticks this GP) idle=1b2/140000000000001/0 softirq=163468/163468 fqs=5151 
	(detected by 0, t=10536 jiffies, g=36899, c=36898, q=280)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 9729 Comm: syz-executor2 Not tainted 4.14.77+ #21
task: ffff8801c65ec680 task.stack: ffff8801d44e0000
RIP: 0010:inb arch/x86/include/asm/io.h:309 [inline]
RIP: 0010:io_serial_in+0x60/0x80 drivers/tty/serial/8250/8250_port.c:450
RSP: 0000:ffff8801dbb07898 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000005 RDI: ffffffff9d91fad8
RBP: ffffffff9d91faa0 R08: 0000000000000435 R09: ffffffff9cac6848
R10: ffff8801c65ecf78 R11: 0000000000000001 R12: 0000000000000020
R13: fffffbfff3b23f9a R14: fffffbfff3b23f5d R15: ffffffff9d91fcd2
FS:  00007f95b5e24700(0000) GS:ffff8801dbb00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020ca0000 CR3: 000000019ec7c001 CR4: 00000000001606a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 serial_in drivers/tty/serial/8250/8250.h:115 [inline]
 wait_for_xmitr+0x90/0x1e0 drivers/tty/serial/8250/8250_port.c:2032
 serial8250_console_putchar+0x19/0x50 drivers/tty/serial/8250/8250_port.c:3184
 uart_console_write+0x4b/0xd0 drivers/tty/serial/serial_core.c:1883
 serial8250_console_write+0x51b/0x800 drivers/tty/serial/8250/8250_port.c:3250
 call_console_drivers kernel/printk/printk.c:1574 [inline]
 console_unlock+0x5b9/0xb50 kernel/printk/printk.c:2242
 vprintk_emit+0x112/0x150 kernel/printk/printk.c:1766
 vprintk_func+0x58/0x159 kernel/printk/printk_safe.c:401
 printk+0xa7/0xcf kernel/printk/printk.c:1838
 print_cpu_stall_info+0x38d/0x6e0 kernel/rcu/tree_plugin.h:1700
 print_cpu_stall kernel/rcu/tree.c:1531 [inline]
 check_cpu_stall kernel/rcu/tree.c:1610 [inline]
 __rcu_pending kernel/rcu/tree.c:3373 [inline]
 rcu_pending kernel/rcu/tree.c:3435 [inline]
 rcu_check_callbacks.cold.56+0x240/0xd99 kernel/rcu/tree.c:2775
 update_process_times+0x24/0x60 kernel/time/timer.c:1588
 tick_sched_handle.isra.8+0x73/0x150 kernel/time/tick-sched.c:161
 tick_sched_timer+0x7e/0x160 kernel/time/tick-sched.c:1321
 __run_hrtimer kernel/time/hrtimer.c:1259 [inline]
 __hrtimer_run_queues+0x2d0/0xc10 kernel/time/hrtimer.c:1323
 hrtimer_interrupt+0x19a/0x440 kernel/time/hrtimer.c:1357
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline]
 smp_apic_timer_interrupt+0x13a/0x5f0 arch/x86/kernel/apic/apic.c:1062
 apic_timer_interrupt+0x84/0x90 arch/x86/entry/entry_64.S:787
 </IRQ>
RIP: 0010:__sanitizer_cov_trace_pc+0x48/0x60 kernel/kcov.c:88
RSP: 0000:ffff8801d44e72e8 EFLAGS: 00000283 ORIG_RAX: ffffffffffffff10
RAX: 0000000000040000 RBX: ffff8801d44e75f8 RCX: 0000000000000001
RDX: ffffffff813e62a7 RSI: ffffc900023a8000 RDI: 0000000000000001
RBP: ffff8801bdc5aa80 R08: 0000000000000010 R09: 000000001087966c
R10: ffffed0043fffa09 R11: 000001a62146f7a6 R12: ffffffff9bb1cc80
R13: 0000000000000008 R14: ffff8801d44e73c8 R15: dffffc0000000000
 __read_once_size include/linux/compiler.h:183 [inline]
 atomic64_read arch/x86/include/asm/atomic64_64.h:22 [inline]
 atomic_long_read include/asm-generic/atomic-long.h:45 [inline]
 perf_event_count kernel/events/core.c:3720 [inline]
 perf_output_read_group kernel/events/core.c:5872 [inline]
 perf_output_read+0x547/0xfb0 kernel/events/core.c:5909
 perf_output_sample+0x10dd/0x1780 kernel/events/core.c:5951
 __perf_event_output kernel/events/core.c:6261 [inline]
 perf_event_output_forward+0x121/0x230 kernel/events/core.c:6274
 __perf_event_overflow+0x116/0x320 kernel/events/core.c:7510
 perf_swevent_overflow+0x166/0x1f0 kernel/events/core.c:7586
 perf_swevent_event+0x19c/0x270 kernel/events/core.c:7619
 do_perf_sw_event kernel/events/core.c:7727 [inline]
 ___perf_sw_event+0x296/0x480 kernel/events/core.c:7758
 __perf_sw_event+0x3f/0x70 kernel/events/core.c:7770
 perf_sw_event include/linux/perf_event.h:1041 [inline]
 __do_page_fault+0x77f/0xb60 arch/x86/mm/fault.c:1466
 page_fault+0x22/0x50 arch/x86/entry/entry_64.S:1104
RIP: 0010:copy_user_enhanced_fast_string+0x7/0x10 arch/x86/lib/copy_user_64.S:180
RSP: 0000:ffff8801d44e7b98 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000001000 RCX: 00000000000001c0
RDX: 0000000000001000 RSI: 0000000020ca0000 RDI: ffff8801cca4fe40
RBP: 0000000020c9f1c0 R08: 0000000000000000 R09: 0000000000000040
R10: ffffed0039949fff R11: ffff8801cca4ffff R12: ffff8801cca4f000
R13: 00007ffffffff000 R14: 0000000020ca01c0 R15: ffff8801cca4f000
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:55 [inline]
 copyin+0x99/0xc0 lib/iov_iter.c:146
 copy_page_from_iter_iovec lib/iov_iter.c:290 [inline]
 copy_page_from_iter+0x320/0x7a0 lib/iov_iter.c:731
 pipe_write+0x21a/0xd30 fs/pipe.c:434
 call_write_iter include/linux/fs.h:1782 [inline]
 new_sync_write fs/read_write.c:471 [inline]
 __vfs_write+0x417/0x5c0 fs/read_write.c:484
 vfs_write+0x17f/0x4d0 fs/read_write.c:546
 SYSC_write fs/read_write.c:593 [inline]
 SyS_write+0xc2/0x1a0 fs/read_write.c:585
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x457569
RSP: 002b:00007f95b5e23c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 00000000fffffef3 RSI: 00000000200001c0 RDI: 0000000000000007
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f95b5e246d4
R13: 00000000004c2883 R14: 00000000004d8568 R15: 00000000ffffffff
Code: 30 0f b6 8d d1 00 00 00 48 8d 7d 38 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 d3 e3 80 3c 02 00 75 13 03 5d 38 89 da ec <0f> b6 c0 5b 5d c3 e8 55 35 7d ff eb c9 e8 7e 35 7d ff eb e6 66 
	 (t=10536 jiffies g=36899 c=36898 q=280)
NMI backtrace for cpu 1
CPU: 1 PID: 9729 Comm: syz-executor2 Not tainted 4.14.77+ #21
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x11b lib/dump_stack.c:53
 nmi_cpu_backtrace.cold.0+0x47/0x85 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x121/0x146 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:156 [inline]
 rcu_dump_cpu_stacks+0x171/0x1bf kernel/rcu/tree.c:1396
 print_cpu_stall kernel/rcu/tree.c:1542 [inline]
 check_cpu_stall kernel/rcu/tree.c:1610 [inline]
 __rcu_pending kernel/rcu/tree.c:3373 [inline]
 rcu_pending kernel/rcu/tree.c:3435 [inline]
 rcu_check_callbacks.cold.56+0x478/0xd99 kernel/rcu/tree.c:2775
 update_process_times+0x24/0x60 kernel/time/timer.c:1588
 tick_sched_handle.isra.8+0x73/0x150 kernel/time/tick-sched.c:161
 tick_sched_timer+0x7e/0x160 kernel/time/tick-sched.c:1321
 __run_hrtimer kernel/time/hrtimer.c:1259 [inline]
 __hrtimer_run_queues+0x2d0/0xc10 kernel/time/hrtimer.c:1323
 hrtimer_interrupt+0x19a/0x440 kernel/time/hrtimer.c:1357
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline]
 smp_apic_timer_interrupt+0x13a/0x5f0 arch/x86/kernel/apic/apic.c:1062
 apic_timer_interrupt+0x84/0x90 arch/x86/entry/entry_64.S:787
 </IRQ>
RIP: 0010:__sanitizer_cov_trace_pc+0x48/0x60 kernel/kcov.c:88
RSP: 0000:ffff8801d44e72e8 EFLAGS: 00000283 ORIG_RAX: ffffffffffffff10
RAX: 0000000000040000 RBX: ffff8801d44e75f8 RCX: 0000000000000001
RDX: ffffffff813e62a7 RSI: ffffc900023a8000 RDI: 0000000000000001
RBP: ffff8801bdc5aa80 R08: 0000000000000010 R09: 000000001087966c
R10: ffffed0043fffa09 R11: 000001a62146f7a6 R12: ffffffff9bb1cc80
R13: 0000000000000008 R14: ffff8801d44e73c8 R15: dffffc0000000000
 __read_once_size include/linux/compiler.h:183 [inline]
 atomic64_read arch/x86/include/asm/atomic64_64.h:22 [inline]
 atomic_long_read include/asm-generic/atomic-long.h:45 [inline]
 perf_event_count kernel/events/core.c:3720 [inline]
 perf_output_read_group kernel/events/core.c:5872 [inline]
 perf_output_read+0x547/0xfb0 kernel/events/core.c:5909
 perf_output_sample+0x10dd/0x1780 kernel/events/core.c:5951
 __perf_event_output kernel/events/core.c:6261 [inline]
 perf_event_output_forward+0x121/0x230 kernel/events/core.c:6274
 __perf_event_overflow+0x116/0x320 kernel/events/core.c:7510
 perf_swevent_overflow+0x166/0x1f0 kernel/events/core.c:7586
 perf_swevent_event+0x19c/0x270 kernel/events/core.c:7619
 do_perf_sw_event kernel/events/core.c:7727 [inline]
 ___perf_sw_event+0x296/0x480 kernel/events/core.c:7758
 __perf_sw_event+0x3f/0x70 kernel/events/core.c:7770
 perf_sw_event include/linux/perf_event.h:1041 [inline]
 __do_page_fault+0x77f/0xb60 arch/x86/mm/fault.c:1466
 page_fault+0x22/0x50 arch/x86/entry/entry_64.S:1104
RIP: 0010:copy_user_enhanced_fast_string+0x7/0x10 arch/x86/lib/copy_user_64.S:180
RSP: 0000:ffff8801d44e7b98 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000001000 RCX: 00000000000001c0
RDX: 0000000000001000 RSI: 0000000020ca0000 RDI: ffff8801cca4fe40
RBP: 0000000020c9f1c0 R08: 0000000000000000 R09: 0000000000000040
R10: ffffed0039949fff R11: ffff8801cca4ffff R12: ffff8801cca4f000
R13: 00007ffffffff000 R14: 0000000020ca01c0 R15: ffff8801cca4f000
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:55 [inline]
 copyin+0x99/0xc0 lib/iov_iter.c:146
 copy_page_from_iter_iovec lib/iov_iter.c:290 [inline]
 copy_page_from_iter+0x320/0x7a0 lib/iov_iter.c:731
 pipe_write+0x21a/0xd30 fs/pipe.c:434
 call_write_iter include/linux/fs.h:1782 [inline]
 new_sync_write fs/read_write.c:471 [inline]
 __vfs_write+0x417/0x5c0 fs/read_write.c:484
 vfs_write+0x17f/0x4d0 fs/read_write.c:546
 SYSC_write fs/read_write.c:593 [inline]
 SyS_write+0xc2/0x1a0 fs/read_write.c:585
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x457569
RSP: 002b:00007f95b5e23c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 00000000fffffef3 RSI: 00000000200001c0 RDI: 0000000000000007
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f95b5e246d4
R13: 00000000004c2883 R14: 00000000004d8568 R15: 00000000ffffffff