INFO: rcu_sched self-detected stall on CPU
	1-...: (10499 ticks this GP) idle=0ce/140000000000001/0 softirq=91615/91616 fqs=5205 
	 (t=10500 jiffies g=20694 c=20693 q=74)
NMI backtrace for cpu 1
CPU: 1 PID: 12277 Comm: syz-executor2 Not tainted 4.14.84+ #14
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:158 [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/0x600 arch/x86/kernel/apic/apic.c:1062
 apic_timer_interrupt+0x84/0x90 arch/x86/entry/entry_64.S:787
 </IRQ>
RIP: 0010:memcpy include/linux/string.h:344 [inline]
RIP: 0010:memcpy_common kernel/events/internal.h:172 [inline]
RIP: 0010:__output_copy kernel/events/internal.h:176 [inline]
RIP: 0010:perf_output_read_group kernel/events/core.c:5876 [inline]
RIP: 0010:perf_output_read+0x688/0xfb0 kernel/events/core.c:5909
RSP: 0018:ffff8881a0f272f0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: ffff8881cc7f0a48 RBX: ffff8881a0f275f8 RCX: 0000000000000000
RDX: 0000000000000010 RSI: ffff8881a0f273d0 RDI: ffff8881cc7f0a58
RBP: ffff8881d0e25d80 R08: ffffed10398fe14b R09: ffffed10398fe149
R10: ffffed10398fe14a R11: ffff8881cc7f0a57 R12: 0000000000000000
R13: 0000000000000010 R14: ffff8881a0f273d0 R15: dffffc0000000000
 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: 0018:ffff8881a0f27b98 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000001000 RCX: 00000000000001c0
RDX: 0000000000001000 RSI: 00000000204cb000 RDI: ffff8881d0d36e40
RBP: 00000000204ca1c0 R08: 0000000000000000 R09: 0000000000000040
R10: ffffed103a1a6dff R11: ffff8881d0d36fff R12: ffff8881d0d36000
R13: 00007ffffffff000 R14: 00000000204cb1c0 R15: ffff8881d0d36000
 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:00007f20fbe59c78 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: 00007f20fbe5a6d4
R13: 00000000004c2bb4 R14: 00000000004d97c0 R15: 00000000ffffffff
INFO: rcu_preempt self-detected stall on CPU
	1-...: (10488 ticks this GP) idle=0ce/140000000000001/0 softirq=91616/91616 fqs=5196 
INFO: rcu_preempt detected stalls on CPUs/tasks:
	1-...: (10488 ticks this GP) idle=0ce/140000000000001/0 softirq=91616/91616 fqs=5196 
	(detected by 0, t=10533 jiffies, g=26395, c=26394, q=1792)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 12277 Comm: syz-executor2 Not tainted 4.14.84+ #14
task: ffff88819f2e0000 task.stack: ffff8881a0f20000
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: 0018:ffff8881dbb07898 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000005 RDI: ffffffffa2b21b18
RBP: ffffffffa2b21ae0 R08: 0000000000000435 R09: ffffffffa1cc8888
R10: ffff88819f2e08f8 R11: 0000000000000001 R12: 0000000000000020
R13: fffffbfff45643a2 R14: fffffbfff4564365 R15: ffffffffa2b21d12
FS:  00007f20fbe5a700(0000) GS:ffff8881dbb00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000204cb000 CR3: 00000001d18f4005 CR4: 00000000001606a0
DR0: 0000000020000000 DR1: 0000000020000000 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:1579 [inline]
 console_unlock+0x5b9/0xb50 kernel/printk/printk.c:2241
 vprintk_emit+0x142/0x180 kernel/printk/printk.c:1777
 vprintk_func+0x58/0x159 kernel/printk/printk_safe.c:401
 printk+0xa7/0xcf kernel/printk/printk.c:1850
 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/0x600 arch/x86/kernel/apic/apic.c:1062
 apic_timer_interrupt+0x84/0x90 arch/x86/entry/entry_64.S:787
 </IRQ>
RIP: 0010:memcpy include/linux/string.h:344 [inline]
RIP: 0010:memcpy_common kernel/events/internal.h:172 [inline]
RIP: 0010:__output_copy kernel/events/internal.h:176 [inline]
RIP: 0010:perf_output_read_group kernel/events/core.c:5876 [inline]
RIP: 0010:perf_output_read+0x688/0xfb0 kernel/events/core.c:5909
RSP: 0018:ffff8881a0f272f0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: ffff8881cc7f0a48 RBX: ffff8881a0f275f8 RCX: 0000000000000000
RDX: 0000000000000010 RSI: ffff8881a0f273d0 RDI: ffff8881cc7f0a58
RBP: ffff8881d0e25d80 R08: ffffed10398fe14b R09: ffffed10398fe149
R10: ffffed10398fe14a R11: ffff8881cc7f0a57 R12: 0000000000000000
R13: 0000000000000010 R14: ffff8881a0f273d0 R15: dffffc0000000000
 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: 0018:ffff8881a0f27b98 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000001000 RCX: 00000000000001c0
RDX: 0000000000001000 RSI: 00000000204cb000 RDI: ffff8881d0d36e40
RBP: 00000000204ca1c0 R08: 0000000000000000 R09: 0000000000000040
R10: ffffed103a1a6dff R11: ffff8881d0d36fff R12: ffff8881d0d36000
R13: 00007ffffffff000 R14: 00000000204cb1c0 R15: ffff8881d0d36000
 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:00007f20fbe59c78 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: 00007f20fbe5a6d4
R13: 00000000004c2bb4 R14: 00000000004d97c0 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 05 5c 7c ff eb c9 e8 2e 5c 7c ff eb e6 66 
	 (t=10533 jiffies g=26395 c=26394 q=1792)
NMI backtrace for cpu 1
CPU: 1 PID: 12277 Comm: syz-executor2 Not tainted 4.14.84+ #14
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:158 [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/0x600 arch/x86/kernel/apic/apic.c:1062
 apic_timer_interrupt+0x84/0x90 arch/x86/entry/entry_64.S:787
 </IRQ>
RIP: 0010:memcpy include/linux/string.h:344 [inline]
RIP: 0010:memcpy_common kernel/events/internal.h:172 [inline]
RIP: 0010:__output_copy kernel/events/internal.h:176 [inline]
RIP: 0010:perf_output_read_group kernel/events/core.c:5876 [inline]
RIP: 0010:perf_output_read+0x688/0xfb0 kernel/events/core.c:5909
RSP: 0018:ffff8881a0f272f0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: ffff8881cc7f0a48 RBX: ffff8881a0f275f8 RCX: 0000000000000000
RDX: 0000000000000010 RSI: ffff8881a0f273d0 RDI: ffff8881cc7f0a58
RBP: ffff8881d0e25d80 R08: ffffed10398fe14b R09: ffffed10398fe149
R10: ffffed10398fe14a R11: ffff8881cc7f0a57 R12: 0000000000000000
R13: 0000000000000010 R14: ffff8881a0f273d0 R15: dffffc0000000000
 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: 0018:ffff8881a0f27b98 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000001000 RCX: 00000000000001c0
RDX: 0000000000001000 RSI: 00000000204cb000 RDI: ffff8881d0d36e40
RBP: 00000000204ca1c0 R08: 0000000000000000 R09: 0000000000000040
R10: ffffed103a1a6dff R11: ffff8881d0d36fff R12: ffff8881d0d36000
R13: 00007ffffffff000 R14: 00000000204cb1c0 R15: ffff8881d0d36000
 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:00007f20fbe59c78 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: 00007f20fbe5a6d4
R13: 00000000004c2bb4 R14: 00000000004d97c0 R15: 00000000ffffffff