INFO: rcu_preempt self-detected stall on CPU
	1-...: (10499 ticks this GP) idle=8b2/140000000000001/0 softirq=81976/81978 fqs=5177 
	 (t=10500 jiffies g=27776 c=27775 q=5517)
NMI backtrace for cpu 1
CPU: 1 PID: 31239 Comm: syz-executor4 Not tainted 4.14.85+ #15
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:3382 [inline]
 rcu_pending kernel/rcu/tree.c:3444 [inline]
 rcu_check_callbacks.cold.56+0x478/0xd99 kernel/rcu/tree.c:2784
 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+0x1f/0x50 mm/kasan/kasan.c:302
RSP: 0018:ffff88819d23f2d0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: ffffed1033a47e79 RBX: 0000000000000008 RCX: ffffffffa85e6688
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88819d23f3c0
RBP: ffff8881d6e87408 R08: ffffed1033a47e79 R09: ffffed1033a47e78
R10: ffffed1033a47e78 R11: ffff88819d23f3c7 R12: ffff88819d23f3c0
R13: 0000000000000008 R14: ffff88819d23f3c8 R15: dffffc0000000000
 memcpy include/linux/string.h:344 [inline]
 memcpy_common kernel/events/internal.h:172 [inline]
 __output_copy kernel/events/internal.h:176 [inline]
 perf_output_read_group kernel/events/core.c:5876 [inline]
 perf_output_read+0x688/0xfb0 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: 0018:ffff88819d23fb98 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000001000 RCX: 00000000000001c0
RDX: 0000000000001000 RSI: 0000000020f00000 RDI: ffff888198c74e40
RBP: 0000000020eff1c0 R08: 0000000000000000 R09: 0000000000000040
R10: ffffed103318e9ff R11: ffff888198c74fff R12: ffff888198c74000
R13: 00007ffffffff000 R14: 0000000020f001c0 R15: ffff888198c74000
 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:1784 [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:00007f3e0c809c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 00000000fffffef3 RSI: 00000000200001c0 RDI: 0000000000000008
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3e0c80a6d4
R13: 00000000004c2bb4 R14: 00000000004d97c0 R15: 00000000ffffffff
INFO: rcu_sched self-detected stall on CPU
	1-...: (10483 ticks this GP) idle=8b2/140000000000001/0 softirq=81978/81978 fqs=5168 
INFO: rcu_sched detected stalls on CPUs/tasks:
	1-...: (10483 ticks this GP) idle=8b2/140000000000001/0 softirq=81978/81978 fqs=5168 
	(detected by 0, t=10533 jiffies, g=19210, c=19209, q=304)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 31239 Comm: syz-executor4 Not tainted 4.14.85+ #15
task: ffff8881ca08de00 task.stack: ffff88819d238000
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: ffffffffac521b58
RBP: ffffffffac521b20 R08: 0000000000000435 R09: ffffffffab6c8888
R10: ffff8881ca08e6f8 R11: 0000000000000001 R12: 0000000000000020
R13: fffffbfff58a43aa R14: fffffbfff58a436d R15: ffffffffac521d52
FS:  00007f3e0c80a700(0000) GS:ffff8881dbb00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020f00000 CR3: 0000000192d44006 CR4: 00000000001606a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
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:3382 [inline]
 rcu_pending kernel/rcu/tree.c:3444 [inline]
 rcu_check_callbacks.cold.56+0x240/0xd99 kernel/rcu/tree.c:2784
 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+0x1f/0x50 mm/kasan/kasan.c:302
RSP: 0018:ffff88819d23f2d0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: ffffed1033a47e79 RBX: 0000000000000008 RCX: ffffffffa85e6688
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88819d23f3c0
RBP: ffff8881d6e87408 R08: ffffed1033a47e79 R09: ffffed1033a47e78
R10: ffffed1033a47e78 R11: ffff88819d23f3c7 R12: ffff88819d23f3c0
R13: 0000000000000008 R14: ffff88819d23f3c8 R15: dffffc0000000000
 memcpy include/linux/string.h:344 [inline]
 memcpy_common kernel/events/internal.h:172 [inline]
 __output_copy kernel/events/internal.h:176 [inline]
 perf_output_read_group kernel/events/core.c:5876 [inline]
 perf_output_read+0x688/0xfb0 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: 0018:ffff88819d23fb98 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000001000 RCX: 00000000000001c0
RDX: 0000000000001000 RSI: 0000000020f00000 RDI: ffff888198c74e40
RBP: 0000000020eff1c0 R08: 0000000000000000 R09: 0000000000000040
R10: ffffed103318e9ff R11: ffff888198c74fff R12: ffff888198c74000
R13: 00007ffffffff000 R14: 0000000020f001c0 R15: ffff888198c74000
 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:1784 [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:00007f3e0c809c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 00000000fffffef3 RSI: 00000000200001c0 RDI: 0000000000000008
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3e0c80a6d4
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 65 53 7c ff eb c9 e8 8e 53 7c ff eb e6 66 
	 (t=10533 jiffies g=19210 c=19209 q=304)
NMI backtrace for cpu 1
CPU: 1 PID: 31239 Comm: syz-executor4 Not tainted 4.14.85+ #15
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:3382 [inline]
 rcu_pending kernel/rcu/tree.c:3444 [inline]
 rcu_check_callbacks.cold.56+0x478/0xd99 kernel/rcu/tree.c:2784
 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+0x1f/0x50 mm/kasan/kasan.c:302
RSP: 0018:ffff88819d23f2d0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: ffffed1033a47e79 RBX: 0000000000000008 RCX: ffffffffa85e6688
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88819d23f3c0
RBP: ffff8881d6e87408 R08: ffffed1033a47e79 R09: ffffed1033a47e78
R10: ffffed1033a47e78 R11: ffff88819d23f3c7 R12: ffff88819d23f3c0
R13: 0000000000000008 R14: ffff88819d23f3c8 R15: dffffc0000000000
 memcpy include/linux/string.h:344 [inline]
 memcpy_common kernel/events/internal.h:172 [inline]
 __output_copy kernel/events/internal.h:176 [inline]
 perf_output_read_group kernel/events/core.c:5876 [inline]
 perf_output_read+0x688/0xfb0 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: 0018:ffff88819d23fb98 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000001000 RCX: 00000000000001c0
RDX: 0000000000001000 RSI: 0000000020f00000 RDI: ffff888198c74e40
RBP: 0000000020eff1c0 R08: 0000000000000000 R09: 0000000000000040
R10: ffffed103318e9ff R11: ffff888198c74fff R12: ffff888198c74000
R13: 00007ffffffff000 R14: 0000000020f001c0 R15: ffff888198c74000
 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:1784 [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:00007f3e0c809c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 00000000fffffef3 RSI: 00000000200001c0 RDI: 0000000000000008
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3e0c80a6d4
R13: 00000000004c2bb4 R14: 00000000004d97c0 R15: 00000000ffffffff