Re: [PATCH V3] x86: call smp vmxoff in smp stop

[Paolo Bonzini]

On 18/01/2017 03:19, Xishi Qiu wrote:
> On 2017/1/17 23:18, Paolo Bonzini wrote:
> 
>>
>>
>> On 14/01/2017 02:42, Xishi Qiu wrote:
>>> From: Tiantian Feng <fengtiantian@xxxxxxxxxx>
>>>
>>> We need to disable VMX on all CPUs before stop cpu when OS panic,
>>> otherwisewe risk hanging up the machine, because the CPU ignore INIT
>>> signals when VMX is enabled. In kernel mainline this issue existence.
>>>
>>> Signed-off-by: Tiantian Feng <fengtiantian@xxxxxxxxxx>
>>
>> Xishi,
>>
>> it's still missing your Signed-off-by.
>>
> 
> Hi Paolo,
> 
> This patch is from fengtiantian, and I just send it for him,
> so still should add my SOB?

Yes, both of them should be there.  The "signed-off-by" is a sequence of
all people that managed the patch---so that would be Tiantian first,
then you, then an x86 maintainer.

Paolo

> Thanks,
> Xishi Qiu
> 
>> Paolo
>>
>>> ---
>>>  arch/x86/kernel/smp.c | 3 +++
>>>  1 file changed, 3 insertions(+)
>>>
>>> diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c
>>> index 68f8cc2..b574d55 100644
>>> --- a/arch/x86/kernel/smp.c
>>> +++ b/arch/x86/kernel/smp.c
>>> @@ -33,6 +33,7 @@
>>>  #include <asm/mce.h>
>>>  #include <asm/trace/irq_vectors.h>
>>>  #include <asm/kexec.h>
>>> +#include <asm/virtext.h>
>>>  
>>>  /*
>>>   *	Some notes on x86 processor bugs affecting SMP operation:
>>> @@ -162,6 +163,7 @@ static int smp_stop_nmi_callback(unsigned int val, struct pt_regs *regs)
>>>  	if (raw_smp_processor_id() == atomic_read(&stopping_cpu))
>>>  		return NMI_HANDLED;
>>>  
>>> +	cpu_emergency_vmxoff();
>>>  	stop_this_cpu(NULL);
>>>  
>>>  	return NMI_HANDLED;
>>> @@ -174,6 +176,7 @@ static int smp_stop_nmi_callback(unsigned int val, struct pt_regs *regs)
>>>  asmlinkage __visible void smp_reboot_interrupt(void)
>>>  {
>>>  	ipi_entering_ack_irq();
>>> +	cpu_emergency_vmxoff();
>>>  	stop_this_cpu(NULL);
>>>  	irq_exit();
>>>  }
>>>
>>
>> .
>>
> 
> 
>