NAK: [SRU][F][PATCH 2/5] x86/kvm: Teardown PV features on boot CPU as well

[Krzysztof Kozlowski]

On 20/05/2021 13:21, Krzysztof Kozlowski wrote:
> On 20/05/2021 09:36, Andrea Righi wrote:
>> From: Vitaly Kuznetsov <vkuznets at redhat.com>
>>
>> BugLink: https://bugs.launchpad.net/bugs/1920944
>>
>> Various PV features (Async PF, PV EOI, steal time) work through memory
>> shared with hypervisor and when we restore from hibernation we must
>> properly teardown all these features to make sure hypervisor doesn't
>> write to stale locations after we jump to the previously hibernated kernel
>> (which can try to place anything there). For secondary CPUs the job is
>> already done by kvm_cpu_down_prepare(), register syscore ops to do
>> the same for boot CPU.
>>
>> Signed-off-by: Vitaly Kuznetsov <vkuznets at redhat.com>
>> Message-Id: <20210414123544.1060604-3-vkuznets at redhat.com>
>> Signed-off-by: Paolo Bonzini <pbonzini at redhat.com>
>> (backported from 8b79feffeca28c5459458fe78676b081e87c93a4)
> 
> Same as for your v3 - this differs significantly against mainline, so it
> should be mentioned what changed. The kvm_guest_cpu_offline() location
> looks now wrong.

Let it be a nack as it fails to build with !SMP because of above:

../arch/x86/kernel/kvm.c: In function 'kvm_suspend':
../arch/x86/kernel/kvm.c:619:2: error: implicit declaration of function 'kvm_guest_cpu_offline' [-Werror=implicit-function-declaration]
  kvm_guest_cpu_offline(false);
  ^
../arch/x86/kernel/kvm.c: In function 'kvm_resume':
../arch/x86/kernel/kvm.c:626:2: error: implicit declaration of function 'kvm_cpu_online' [-Werror=implicit-function-declaration]
  kvm_cpu_online(raw_smp_processor_id());
  ^


Best regards,
Krzysztof