linux-kernel - Re: Regression: sched/preempt: Add static_key() to preempt

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

Date:	Tue, 30 Jun 2015 09:47:44 -0400
From:	Josh Boyer <jwboyer@...oraproject.org>
To:	Pontus Fuchs <pontus.fuchs@...il.com>
Cc:	Peter Zijlstra <peterz@...radead.org>,
	Ingo Molnar <mingo@...hat.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Gleb Natapov <gleb@...nel.org>
Subject: Re: Regression: sched/preempt: Add static_key() to preempt_notifiers
 breaks my KVM

On Thu, Jun 25, 2015 at 8:15 AM, Pontus Fuchs <pontus.fuchs@...il.com> wrote:
> On 2015-06-25 14:09, Peter Zijlstra wrote:
>>
>> On Thu, Jun 25, 2015 at 02:00:02PM +0200, Pontus Fuchs wrote:
>>>
>>> Hi,
>>>
>>
>> That seems pointless..
>>
>> ---
>>   virt/kvm/kvm_main.c | 5 +++--
>>   1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
>> index 90977418aeb6..d7aafa0458a0 100644
>> --- a/virt/kvm/kvm_main.c
>> +++ b/virt/kvm/kvm_main.c
>> @@ -128,8 +128,9 @@ int vcpu_load(struct kvm_vcpu *vcpu)
>>
>>         if (mutex_lock_killable(&vcpu->mutex))
>>                 return -EINTR;
>> -       cpu = get_cpu();
>>         preempt_notifier_register(&vcpu->preempt_notifier);
>> +
>> +       cpu = get_cpu();
>>         kvm_arch_vcpu_load(vcpu, cpu);
>>         put_cpu();
>>         return 0;
>> @@ -139,8 +140,8 @@ void vcpu_put(struct kvm_vcpu *vcpu)
>>   {
>>         preempt_disable();
>>         kvm_arch_vcpu_put(vcpu);
>> -       preempt_notifier_unregister(&vcpu->preempt_notifier);
>>         preempt_enable();
>> +       preempt_notifier_unregister(&vcpu->preempt_notifier);
>>         mutex_unlock(&vcpu->mutex);
>>   }
>
>
> Tested ok. Thanks.

We've had a report of this in Fedora now.  Is the above patch queued anywhere?

https://bugzilla.redhat.com/show_bug.cgi?id=1237143

josh
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/