2015-02-20 21:58:55

by Joel Schopp

Subject: [PATCH v2] x86: svm: use kvm_register_write()/read()

From: David Kaplan <[email protected]>

KVM has nice wrappers to access the register values, clean up a few places
that should use them but currently do not.

Signed-off-by: David Kaplan <[email protected]>
[forward port and testing]
Signed-off-by: Joel Schopp <[email protected]>
---
arch/x86/kvm/svm.c | 19 +++++++++----------
1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index d319e0c..a7d88e4 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -2757,11 +2757,11 @@ static int invlpga_interception(struct vcpu_svm *svm)
{
struct kvm_vcpu *vcpu = &svm->vcpu;

- trace_kvm_invlpga(svm->vmcb->save.rip, vcpu->arch.regs[VCPU_REGS_RCX],
- vcpu->arch.regs[VCPU_REGS_RAX]);
+ trace_kvm_invlpga(svm->vmcb->save.rip, kvm_register_read(&svm->vcpu, VCPU_REGS_RCX),
+ kvm_register_read(&svm->vcpu, VCPU_REGS_RAX));

/* Let's treat INVLPGA the same as INVLPG (can be optimized!) */
- kvm_mmu_invlpg(vcpu, vcpu->arch.regs[VCPU_REGS_RAX]);
+ kvm_mmu_invlpg(vcpu, kvm_register_read(&svm->vcpu, VCPU_REGS_RAX));

svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
skip_emulated_instruction(&svm->vcpu);
@@ -2770,7 +2770,7 @@ static int invlpga_interception(struct vcpu_svm *svm)

static int skinit_interception(struct vcpu_svm *svm)
{
- trace_kvm_skinit(svm->vmcb->save.rip, svm->vcpu.arch.regs[VCPU_REGS_RAX]);
+ trace_kvm_skinit(svm->vmcb->save.rip, kvm_register_read(&svm->vcpu, VCPU_REGS_RAX));

kvm_queue_exception(&svm->vcpu, UD_VECTOR);
return 1;
@@ -3133,7 +3133,7 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, unsigned ecx, u64 *data)

static int rdmsr_interception(struct vcpu_svm *svm)
{
- u32 ecx = svm->vcpu.arch.regs[VCPU_REGS_RCX];
+ u32 ecx = kvm_register_read(&svm->vcpu, VCPU_REGS_RCX);
u64 data;

if (svm_get_msr(&svm->vcpu, ecx, &data)) {
@@ -3142,8 +3142,8 @@ static int rdmsr_interception(struct vcpu_svm *svm)
} else {
trace_kvm_msr_read(ecx, data);

- svm->vcpu.arch.regs[VCPU_REGS_RAX] = data & 0xffffffff;
- svm->vcpu.arch.regs[VCPU_REGS_RDX] = data >> 32;
+ kvm_register_write(&svm->vcpu, VCPU_REGS_RAX, data & 0xffffffff);
+ kvm_register_write(&svm->vcpu, VCPU_REGS_RDX, data >> 32);
svm->next_rip = kvm_rip_read(&svm->vcpu) + 2;
skip_emulated_instruction(&svm->vcpu);
}
@@ -3246,9 +3246,8 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
static int wrmsr_interception(struct vcpu_svm *svm)
{
struct msr_data msr;
- u32 ecx = svm->vcpu.arch.regs[VCPU_REGS_RCX];
- u64 data = (svm->vcpu.arch.regs[VCPU_REGS_RAX] & -1u)
- | ((u64)(svm->vcpu.arch.regs[VCPU_REGS_RDX] & -1u) << 32);
+ u32 ecx = kvm_register_read(&svm->vcpu, VCPU_REGS_RCX);
+ u64 data = kvm_read_edx_eax(&svm->vcpu);

msr.data = data;
msr.index = ecx;

2015-02-20 23:22:15

by Borislav Petkov

Subject: Re: [PATCH v2] x86: svm: use kvm_register_write()/read()

On Fri, Feb 20, 2015 at 04:02:10PM -0600, Joel Schopp wrote:
> From: David Kaplan <[email protected]>
>
> KVM has nice wrappers to access the register values, clean up a few places
> that should use them but currently do not.
>
> Signed-off-by: David Kaplan <[email protected]>
> [forward port and testing]
> Signed-off-by: Joel Schopp <[email protected]>

Looks good.

Acked-by: Borislav Petkov <[email protected]>

> ---
> arch/x86/kvm/svm.c | 19 +++++++++----------
> 1 file changed, 9 insertions(+), 10 deletions(-)
>
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index d319e0c..a7d88e4 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c

...

> @@ -3142,8 +3142,8 @@ static int rdmsr_interception(struct vcpu_svm *svm)
> } else {
> trace_kvm_msr_read(ecx, data);
>
> - svm->vcpu.arch.regs[VCPU_REGS_RAX] = data & 0xffffffff;
> - svm->vcpu.arch.regs[VCPU_REGS_RDX] = data >> 32;
> + kvm_register_write(&svm->vcpu, VCPU_REGS_RAX, data & 0xffffffff);
> + kvm_register_write(&svm->vcpu, VCPU_REGS_RDX, data >> 32);

Right, kvm is missing kvm_write_edx_eax() in addition to the read
variant. Someone might want to do a patch and such, ^^hint hint^^...

:-)

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.
--

2015-02-25 22:27:17

by Marcelo Tosatti

Subject: Re: [PATCH v2] x86: svm: use kvm_register_write()/read()

On Sat, Feb 21, 2015 at 12:21:16AM +0100, Borislav Petkov wrote:
> On Fri, Feb 20, 2015 at 04:02:10PM -0600, Joel Schopp wrote:
> > From: David Kaplan <[email protected]>
> >
> > KVM has nice wrappers to access the register values, clean up a few places
> > that should use them but currently do not.
> >
> > Signed-off-by: David Kaplan <[email protected]>
> > [forward port and testing]
> > Signed-off-by: Joel Schopp <[email protected]>
>
> Looks good.
>
> Acked-by: Borislav Petkov <[email protected]>

Applied, thanks.