kvm [5968]: vcpu0, guest rIP: 0xfff0 disabled perfctr wrmsr: 0xc1 data 0x0
INFO: rcu_sched self-detected stall on CPU
INFO: rcu_sched detected stalls on CPUs/tasks:
	1-...!: (124999 ticks this GP) idle=eaa/1/4611686018427387906 softirq=13301/13301 fqs=0 
	(detected by 0, t=125002 jiffies, g=6666, c=6665, q=66)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5965 Comm: syz-executor7 Not tainted 4.15.0-rc6-mm1+ #50
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:rep_nop arch/x86/include/asm/processor.h:659 [inline]
RIP: 0010:delay_tsc+0x41/0x70 arch/x86/lib/delay.c:67
RSP: 0018:ffff8801db5078c8 EFLAGS: 00000003
RAX: 00000059d0d839cd RBX: ffffffff87e4dfe0 RCX: 00000059d0d836ef
RDX: 00000000000002de RSI: 0000000000000001 RDI: 00000000000008fd
RBP: ffff8801db5078c8 R08: ffffffff82547f25 R09: 000000000000000c
R10: ffff8801db5078f8 R11: 0000000000000001 R12: 0000000000002701
R13: 0000000000000020 R14: fffffbfff0fc9c41 R15: fffffbfff0fc9c05
FS:  00007f12c2f27700(0000) GS:ffff8801db500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002040ef98 CR3: 00000001d0b23001 CR4: 00000000001626e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __delay arch/x86/lib/delay.c:161 [inline]
 __const_udelay+0x5b/0x70 arch/x86/lib/delay.c:175
 wait_for_xmitr+0x6f/0x1e0 drivers/tty/serial/8250/8250_port.c:2041
 serial8250_console_putchar+0x1f/0x60 drivers/tty/serial/8250/8250_port.c:3170
 uart_console_write+0xac/0xe0 drivers/tty/serial/serial_core.c:1858
 serial8250_console_write+0x5b3/0x940 drivers/tty/serial/8250/8250_port.c:3236
 univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:590
 call_console_drivers kernel/printk/printk.c:1574 [inline]
 console_unlock+0x6ba/0xc30 kernel/printk/printk.c:2233
 vprintk_emit+0x4ad/0x590 kernel/printk/printk.c:1757
 vprintk_default+0x28/0x30 kernel/printk/printk.c:1796
 vprintk_func+0x57/0xc0 kernel/printk/printk_safe.c:379
 printk+0xaa/0xca kernel/printk/printk.c:1829
 print_cpu_stall_info_begin kernel/rcu/tree_plugin.h:1686 [inline]
 print_cpu_stall kernel/rcu/tree.c:1510 [inline]
 check_cpu_stall kernel/rcu/tree.c:1592 [inline]
 __rcu_pending kernel/rcu/tree.c:3362 [inline]
 rcu_pending kernel/rcu/tree.c:3424 [inline]
 rcu_check_callbacks+0xb68/0x1de0 kernel/rcu/tree.c:2764
 update_process_times+0x30/0x60 kernel/time/timer.c:1628
 tick_sched_handle+0x85/0x160 kernel/time/tick-sched.c:162
 tick_sched_timer+0x42/0x120 kernel/time/tick-sched.c:1176
 __run_hrtimer kernel/time/hrtimer.c:1210 [inline]
 __hrtimer_run_queues+0x2c8/0xb50 kernel/time/hrtimer.c:1274
 hrtimer_interrupt+0x1c2/0x5e0 kernel/time/hrtimer.c:1308
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline]
 smp_apic_timer_interrupt+0xc9/0x4c0 arch/x86/kernel/apic/apic.c:1050
 apic_timer_interrupt+0xa9/0xb0 arch/x86/entry/entry_64.S:920
 </IRQ>
RIP: 0010:memcpy_erms+0x8/0x10 arch/x86/lib/memcpy_64.S:54
RSP: 0018:ffff8801c29df918 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff11
RAX: ffffc9000140cd46 RBX: 0000000000000002 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffff8801c29dfa02 RDI: ffffc9000140cd48
RBP: ffff8801c29df938 R08: fffff520002819a9 R09: fffff520002819a9
R10: 0000000000000001 R11: fffff520002819a8 R12: ffffc9000140cd46
R13: ffff8801c29dfa00 R14: ffff8801cd2d0600 R15: dffffc0000000000
 memcpy include/linux/string.h:344 [inline]
 cvt_s16_to_native sound/core/oss/mulaw.c:164 [inline]
 mulaw_decode+0x50e/0x740 sound/core/oss/mulaw.c:195
 mulaw_transfer+0x222/0x270 sound/core/oss/mulaw.c:273
 snd_pcm_plug_write_transfer+0x20b/0x390 sound/core/oss/pcm_plugin.c:611
 snd_pcm_oss_write2+0x22e/0x3c0 sound/core/oss/pcm_oss.c:1311
 snd_pcm_oss_write1 sound/core/oss/pcm_oss.c:1372 [inline]
 snd_pcm_oss_write+0x4c1/0x690 sound/core/oss/pcm_oss.c:2646
 __vfs_write+0xef/0x740 fs/read_write.c:480
 vfs_write+0x189/0x510 fs/read_write.c:544
 SYSC_write fs/read_write.c:589 [inline]
 SyS_write+0xd4/0x1a0 fs/read_write.c:581
 entry_SYSCALL_64_fastpath+0x23/0x9a
RIP: 0033:0x452ac9
RSP: 002b:00007f12c2f26c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000071bf58 RCX: 0000000000452ac9
RDX: 00000000ffffffa2 RSI: 0000000020001000 RDI: 0000000000000013
RBP: 00000000000004dd R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f5558
R13: 00000000ffffffff R14: 00007f12c2f276d4 R15: 0000000000000008
Code: 31 48 c1 e2 20 48 89 d1 48 09 c1 0f ae e8 0f 31 48 c1 e2 20 48 09 d0 48 89 c2 48 29 ca 48 39 fa 73 25 65 ff 0d d1 ef 33 7b f3 90 <65> ff 05 c8 ef 33 7b 65 8b 15 a1 83 33 7b 39 f2 74 ce 48 29 c1 
rcu_sched kthread starved for 125002 jiffies! g6666 c6665 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0
rcu_sched       R  running task    29712     8      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2800 [inline]
 __schedule+0x850/0x1e10 kernel/sched/core.c:3376
 schedule+0x7c/0x1a0 kernel/sched/core.c:3435
 schedule_timeout+0x46d/0x1150 kernel/time/timer.c:1816
 rcu_gp_kthread+0xbfd/0x19f0 kernel/rcu/tree.c:2231
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:524
	1-...!: (124999 ticks this GP) idle=eaa/1/4611686018427387906 softirq=13301/13301 fqs=0 
	 (t=125645 jiffies g=6666 c=6665 q=66)
rcu_sched kthread starved for 125650 jiffies! g6666 c6665 f0x2 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0
rcu_sched       R  running task    29712     8      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2800 [inline]
 __schedule+0x850/0x1e10 kernel/sched/core.c:3376
 schedule+0x7c/0x1a0 kernel/sched/core.c:3435
 schedule_timeout+0x46d/0x1150 kernel/time/timer.c:1816
 rcu_gp_kthread+0xbfd/0x19f0 kernel/rcu/tree.c:2231
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:524
NMI backtrace for cpu 1
CPU: 1 PID: 5965 Comm: syz-executor7 Not tainted 4.15.0-rc6-mm1+ #50
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x137/0x198 lib/dump_stack.c:53
 nmi_cpu_backtrace+0x1d2/0x210 lib/nmi_backtrace.c:103
 nmi_trigger_cpumask_backtrace+0x122/0x180 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:156 [inline]
 rcu_dump_cpu_stacks+0x186/0x1d7 kernel/rcu/tree.c:1375
 print_cpu_stall kernel/rcu/tree.c:1524 [inline]
 check_cpu_stall kernel/rcu/tree.c:1592 [inline]
 __rcu_pending kernel/rcu/tree.c:3362 [inline]
 rcu_pending kernel/rcu/tree.c:3424 [inline]
 rcu_check_callbacks+0x1a64/0x1de0 kernel/rcu/tree.c:2764
 update_process_times+0x30/0x60 kernel/time/timer.c:1628
 tick_sched_handle+0x85/0x160 kernel/time/tick-sched.c:162
 tick_sched_timer+0x42/0x120 kernel/time/tick-sched.c:1176
 __run_hrtimer kernel/time/hrtimer.c:1210 [inline]
 __hrtimer_run_queues+0x2c8/0xb50 kernel/time/hrtimer.c:1274
 hrtimer_interrupt+0x1c2/0x5e0 kernel/time/hrtimer.c:1308
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline]
 smp_apic_timer_interrupt+0xc9/0x4c0 arch/x86/kernel/apic/apic.c:1050
 apic_timer_interrupt+0xa9/0xb0 arch/x86/entry/entry_64.S:920
 </IRQ>
RIP: 0010:memcpy_erms+0x8/0x10 arch/x86/lib/memcpy_64.S:54
RSP: 0018:ffff8801c29df918 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff11
RAX: ffffc9000140cd46 RBX: 0000000000000002 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffff8801c29dfa02 RDI: ffffc9000140cd48
RBP: ffff8801c29df938 R08: fffff520002819a9 R09: fffff520002819a9
R10: 0000000000000001 R11: fffff520002819a8 R12: ffffc9000140cd46
R13: ffff8801c29dfa00 R14: ffff8801cd2d0600 R15: dffffc0000000000
 memcpy include/linux/string.h:344 [inline]
 cvt_s16_to_native sound/core/oss/mulaw.c:164 [inline]
 mulaw_decode+0x50e/0x740 sound/core/oss/mulaw.c:195
 mulaw_transfer+0x222/0x270 sound/core/oss/mulaw.c:273
 snd_pcm_plug_write_transfer+0x20b/0x390 sound/core/oss/pcm_plugin.c:611
 snd_pcm_oss_write2+0x22e/0x3c0 sound/core/oss/pcm_oss.c:1311
 snd_pcm_oss_write1 sound/core/oss/pcm_oss.c:1372 [inline]
 snd_pcm_oss_write+0x4c1/0x690 sound/core/oss/pcm_oss.c:2646
 __vfs_write+0xef/0x740 fs/read_write.c:480
 vfs_write+0x189/0x510 fs/read_write.c:544
 SYSC_write fs/read_write.c:589 [inline]
 SyS_write+0xd4/0x1a0 fs/read_write.c:581
 entry_SYSCALL_64_fastpath+0x23/0x9a
RIP: 0033:0x452ac9
RSP: 002b:00007f12c2f26c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000071bf58 RCX: 0000000000452ac9
RDX: 00000000ffffffa2 RSI: 0000000020001000 RDI: 0000000000000013
RBP: 00000000000004dd R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f5558
R13: 00000000ffffffff R14: 00007f12c2f276d4 R15: 0000000000000008