linux-kernel - Re: KVM: BUG during OOM on host

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Wed, 26 Jul 2017 07:14:04 +0800
From:   Wanpeng Li <kernellwp@...il.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     kvm <kvm@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Radim Krcmar <rkrcmar@...hat.com>,
        Wanpeng Li <wanpeng.li@...mail.com>
Subject: Re: KVM: BUG during OOM on host

2017-06-30 1:14 GMT+08:00 Paolo Bonzini <pbonzini@...hat.com>:
>
>
> On 29/06/2017 08:21, Wanpeng Li wrote:
>> Hi all,
>>
>> When the OOM-Killer kills the guest which is running memory hog
>> processes, there is tons of splatting as below: the page count reaches
>> 0 before drop_spte. The splatting will disappear when disables THP on
>> host.
>
> Can you reproduce it in 4.10?

Sorry for the late response, it can't be reproduced in 4.10 Linus tree.

Regards,
Wanpeng Li

>
> Thanks,
>
> Paolo
>
>> ------------[ cut here ]------------
>>  WARNING: CPU: 4 PID: 28317 at arch/x86/kvm/mmu.c:682
>> mmu_spte_clear_track_bits+0x84/0x120 [kvm]
>>  CPU: 4 PID: 28317 Comm: kworker/4:2 Tainted: G    B D W       4.12.0-rc7+ #29
>>  Workqueue: events mmput_async_fn
>>  task: ffff9465283c3280 task.stack: ffffacb0083b4000
>>  RIP: 0010:mmu_spte_clear_track_bits+0x84/0x120 [kvm]
>>  Call Trace:
>>   drop_spte+0x1a/0xb0 [kvm]
>>   mmu_page_zap_pte+0xcc/0xe0 [kvm]
>>   kvm_mmu_prepare_zap_page+0x81/0x4c0 [kvm]
>>   ? _raw_spin_lock+0x65/0x70
>>   kvm_mmu_invalidate_zap_all_pages+0x171/0x240 [kvm]
>>   kvm_arch_flush_shadow_all+0xe/0x10 [kvm]
>>   kvm_mmu_notifier_release+0x54/0x90 [kvm]
>>   ? kvm_mmu_notifier_release+0x5/0x90 [kvm]
>>   __mmu_notifier_release+0x65/0x100
>>   exit_mmap+0x168/0x180
>>   ? __khugepaged_exit+0xdb/0x140
>>   ? rcu_read_lock_sched_held+0x79/0x80
>>   ? kmem_cache_free+0x2f2/0x350
>>   mmput_async_fn+0x4c/0x140
>>   process_one_work+0x203/0x690
>>   worker_thread+0x4e/0x3b0
>>   kthread+0x117/0x150
>>
>> Regards,
>> Wanpeng Li
>>