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INFO: rcu detected stall in kvm_mmu_unprotect_page

Status: closed as dup on 2018/09/11 07:36
Subsystems: kvm
[Documentation on labels]
Reported-by: syzbot+3656615bd54615add56a@syzkaller.appspotmail.com
First crash: 2061d, last: 2061d
▶ ▼ Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
INFO: rcu detected stall in kvm_vcpu_ioctl mm C error unreliable 251 882d 2059d
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
INFO: rcu detected stall in kvm_mmu_unprotect_page 1 (2) 2018/09/11 07:36

Sample crash report:
8021q: adding VLAN 0 to HW filter on device team0
8021q: adding VLAN 0 to HW filter on device team0
8021q: adding VLAN 0 to HW filter on device team0
hrtimer: interrupt took 30378 ns
L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/l1tf.html for details.
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=7113, q=509)
rcu: All QSes seen, last rcu_preempt kthread activity 10498 (4295042895-4295032397), jiffies_till_next_fqs=1, root ->qsmask 0x0
syz-executor0   R  running task    22808  7363   5346 0x00000000
Call Trace:
 <IRQ>
 sched_show_task.cold.83+0x2b6/0x30a kernel/sched/core.c:5296
 print_other_cpu_stall.cold.79+0xa83/0xba5 kernel/rcu/tree.c:1430
 check_cpu_stall kernel/rcu/tree.c:1557 [inline]
 __rcu_pending kernel/rcu/tree.c:3276 [inline]
 rcu_pending kernel/rcu/tree.c:3319 [inline]
 rcu_check_callbacks+0xafc/0x1990 kernel/rcu/tree.c:2665
 update_process_times+0x2d/0x70 kernel/time/timer.c:1636
 tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164
 tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0x41c/0x10d0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x313/0x780 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1029 [inline]
 smp_apic_timer_interrupt+0x1a1/0x760 arch/x86/kernel/apic/apic.c:1054
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:864
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:788 [inline]
RIP: 0010:lock_acquire+0x268/0x520 kernel/locking/lockdep.c:3904
Code: 00 00 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 44 02 00 00 48 83 3d af 39 f1 07 00 0f 84 c3 01 00 00 48 8b bd 20 ff ff ff 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00
RSP: 0018:ffff8801c664eb20 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: 1ffff10038cc9d69 RCX: 0000000000000000
RDX: 1ffffffff12a4535 RSI: 0000000000000000 RDI: 0000000000000282
RBP: ffff8801c664ec10 R08: ffff8801c10e6e70 R09: 0000000000000002
R10: ffff8801c10e6e50 R11: f333abdc872bc457 R12: ffff8801c10e6580
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2d/0x40 kernel/locking/spinlock.c:144
 spin_lock include/linux/spinlock.h:329 [inline]
 kvm_mmu_unprotect_page+0xf9/0x450 arch/x86/kvm/mmu.c:2720
 retry_instruction arch/x86/kvm/x86.c:5982 [inline]
 x86_emulate_instruction+0x635/0x1fc0 arch/x86/kvm/x86.c:6210
 kvm_mmu_page_fault+0x396/0x1b30 arch/x86/kvm/mmu.c:5280
 handle_ept_violation+0x29e/0x6a0 arch/x86/kvm/vmx.c:7679
 vmx_handle_exit+0x2f7/0x17e0 arch/x86/kvm/vmx.c:10115
 vcpu_enter_guest+0x14a9/0x62e0 arch/x86/kvm/x86.c:7648
 vcpu_run arch/x86/kvm/x86.c:7711 [inline]
 kvm_arch_vcpu_ioctl_run+0x375/0x16e0 arch/x86/kvm/x86.c:7888
 kvm_vcpu_ioctl+0x72b/0x1150 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2590
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702
 __do_sys_ioctl fs/ioctl.c:709 [inline]
 __se_sys_ioctl fs/ioctl.c:707 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457099
Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff8bfb2748 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000212b914 RCX: 0000000000457099
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004cf730 R14: 00000000004c59b9 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 10498 jiffies! g7113 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    22872    10      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2825 [inline]
 __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473
 schedule+0xfe/0x460 kernel/sched/core.c:3517
 schedule_timeout+0x140/0x260 kernel/time/timer.c:1804
 rcu_gp_kthread+0x9d9/0x2310 kernel/rcu/tree.c:2194
 kthread+0x35a/0x420 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413
rcu: INFO: rcu_sched detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10652 jiffies, g=-1171, q=0)
rcu: All QSes seen, last rcu_sched kthread activity 10649 (4295043046-4295032397), jiffies_till_next_fqs=1, root ->qsmask 0x0
syz-executor0   R  running task    22808  7363   5346 0x80000000
Call Trace:
 <IRQ>
 sched_show_task.cold.83+0x2b6/0x30a kernel/sched/core.c:5296
 print_other_cpu_stall.cold.79+0xa83/0xba5 kernel/rcu/tree.c:1430
 check_cpu_stall kernel/rcu/tree.c:1557 [inline]
 __rcu_pending kernel/rcu/tree.c:3276 [inline]
 rcu_pending kernel/rcu/tree.c:3319 [inline]
 rcu_check_callbacks+0xafc/0x1990 kernel/rcu/tree.c:2665
 update_process_times+0x2d/0x70 kernel/time/timer.c:1636
 tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164
 tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0x41c/0x10d0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x313/0x780 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1029 [inline]
 smp_apic_timer_interrupt+0x1a1/0x760 arch/x86/kernel/apic/apic.c:1054
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:864
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:788 [inline]
RIP: 0010:lock_acquire+0x268/0x520 kernel/locking/lockdep.c:3904
Code: 00 00 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 44 02 00 00 48 83 3d af 39 f1 07 00 0f 84 c3 01 00 00 48 8b bd 20 ff ff ff 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00
RSP: 0018:ffff8801c664eb20 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: 1ffff10038cc9d69 RCX: 0000000000000000
RDX: 1ffffffff12a4535 RSI: 0000000000000000 RDI: 0000000000000282
RBP: ffff8801c664ec10 R08: ffff8801c10e6e70 R09: 0000000000000002
R10: ffff8801c10e6e50 R11: f333abdc872bc457 R12: ffff8801c10e6580
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2d/0x40 kernel/locking/spinlock.c:144
 spin_lock include/linux/spinlock.h:329 [inline]
 kvm_mmu_unprotect_page+0xf9/0x450 arch/x86/kvm/mmu.c:2720
 retry_instruction arch/x86/kvm/x86.c:5982 [inline]
 x86_emulate_instruction+0x635/0x1fc0 arch/x86/kvm/x86.c:6210
 kvm_mmu_page_fault+0x396/0x1b30 arch/x86/kvm/mmu.c:5280
 handle_ept_violation+0x29e/0x6a0 arch/x86/kvm/vmx.c:7679
 vmx_handle_exit+0x2f7/0x17e0 arch/x86/kvm/vmx.c:10115
 vcpu_enter_guest+0x14a9/0x62e0 arch/x86/kvm/x86.c:7648
 vcpu_run arch/x86/kvm/x86.c:7711 [inline]
 kvm_arch_vcpu_ioctl_run+0x375/0x16e0 arch/x86/kvm/x86.c:7888
 kvm_vcpu_ioctl+0x72b/0x1150 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2590
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702
 __do_sys_ioctl fs/ioctl.c:709 [inline]
 __se_sys_ioctl fs/ioctl.c:707 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457099
Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff8bfb2748 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000212b914 RCX: 0000000000457099
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004cf730 R14: 00000000004c59b9 R15: 0000000000000000
rcu: rcu_sched kthread starved for 10649 jiffies! g-1171 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_sched       R  running task    24600    11      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2825 [inline]
 __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473
 schedule+0xfe/0x460 kernel/sched/core.c:3517
 schedule_timeout+0x140/0x260 kernel/time/timer.c:1804
 rcu_gp_kthread+0x9d9/0x2310 kernel/rcu/tree.c:2194
 kthread+0x35a/0x420 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/09/09 13:54 upstream f8f65382c98a 6b5120a4 .config console log report syz ci-upstream-kasan-gce-root
2018/09/09 05:25 upstream f8f65382c98a 6b5120a4 .config console log report ci-upstream-kasan-gce-root
* Struck through repros no longer work on HEAD.