lkml.org 
[lkml]   [2017]   [Nov]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH v2] KVM: VMX: Fix rflags cache during vCPU reset
2017-11-21 7:09 GMT+08:00 Paolo Bonzini <pbonzini@redhat.com>:
> On 20/11/2017 23:52, Wanpeng Li wrote:
>> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
>> index b348920..131fa1c 100644
>> --- a/arch/x86/kvm/vmx.c
>> +++ b/arch/x86/kvm/vmx.c
>> @@ -5590,6 +5590,7 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
>> vmcs_write64(GUEST_IA32_DEBUGCTL, 0);
>> }
>>
>> + kvm_set_rflags(vcpu, 2);
>> vmcs_writel(GUEST_RFLAGS, 0x02);
>
> I think the vmcs_writel can go, kvm_set_rflags ends up calling
> vmx_set_rflags.

Agreed.

>
>> kvm_rip_write(vcpu, 0xfff0);
>>
>>
>
> Beautified testcase:
>
> #include <unistd.h>
> #include <sys/syscall.h>
> #include <string.h>
> #include <stdint.h>
> #include <linux/kvm.h>
> #include <fcntl.h>
> #include <sys/ioctl.h>
>
> long r[5];
> int main()
> {
> struct kvm_debugregs dr = { 0 };
>
> r[2] = open("/dev/kvm", O_RDONLY);
> r[3] = ioctl(r[2], KVM_CREATE_VM, 0);
> r[4] = ioctl(r[3], KVM_CREATE_VCPU, 7);
> struct kvm_guest_debug debug = {
> .control = 0xf0403,
> .arch = {
> .debugreg[6] = 0x2,
> .debugreg[7] = 0x2
> }
> };
> ioctl(r[4], KVM_SET_GUEST_DEBUG, &debug);
> ioctl(r[4], KVM_RUN, 0);
> }
>
> No need to do anything, I'll handle this patch after -rc1.

Thanks for that. :)

Regards,
Wanpeng Li

\
 
 \ /
  Last update: 2017-11-21 01:35    [W:0.047 / U:1.712 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site