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KVM: Fix OSXSAVE after migration

PATCH Applied Sheng Yang 2 participants 4 messages Dec 8, 2010 – Dec 9, 2010

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Sheng Yang

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#0 lore raw

PATCH 1/1 KVM: Fix OSXSAVE after migration

CPUID's OSXSAVE is a mirror of CR4.OSXSAVE bit. We need to update the CPUID after migration.

Cc [email protected]
Signed-off-by Sheng Yang <[email protected]>
---
 arch/x86/kvm/x86.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
arch/x86/kvm/x86.c +2 -0
index ed373ba..51a2bce 100644
@@ -5585,6 +5585,8 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 
 	mmu_reset_needed |= kvm_read_cr4(vcpu) != sregs->cr4;
 	kvm_x86_ops->set_cr4(vcpu, sregs->cr4);
+	if (sregs->cr4 & X86_CR4_OSXSAVE)
+		update_cpuid(vcpu);
 	if (!is_long_mode(vcpu) && is_pae(vcpu)) {
 		load_pdptrs(vcpu, vcpu->arch.walk_mmu, vcpu->arch.cr3);
 		mmu_reset_needed = 1;
Signature · 1 line
1.7.0.1
Applied
#1 lore raw
Quoted 3 lines · Sheng Yang

CPUID's OSXSAVE is a mirror of CR4.OSXSAVE bit. We need to update the CPUID after migration.

Applied, thanks.

arch/x86/kvm/x86.c int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, · line 5592

Quoted 9 lines
arch/x86/kvm/x86.c +2 -0
@@ -5585,6 +5585,8 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 
  	mmu_reset_needed |= kvm_read_cr4(vcpu) != sregs->cr4;
  	kvm_x86_ops->set_cr4(vcpu, sregs->cr4);
+	if (sregs->cr4&  X86_CR4_OSXSAVE)
+		update_cpuid(vcpu);
  	if (!is_long_mode(vcpu)&&  is_pae(vcpu)) {
  		load_pdptrs(vcpu, vcpu->arch.walk_mmu, vcpu->arch.cr3);
  		mmu_reset_needed = 1;

We really should use kvm_set_crX() here.

Signature · 1 line
error compiling committee.c: too many arguments to function
author
#2 lore raw
Quoted 15 lines · On Wednesday 08 December 2010 18:33:43 Avi Kivity wrote:
Quoted 2 lines · Sheng Yang

CPUID's OSXSAVE is a mirror of CR4.OSXSAVE bit. We need to update the CPUID after migration.

Applied, thanks.

Quoted 9 lines
arch/x86/kvm/x86.c +2 -0
@@ -5585,6 +5585,8 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu
 *vcpu,
 
  	mmu_reset_needed |= kvm_read_cr4(vcpu) != sregs->cr4;
  	kvm_x86_ops->set_cr4(vcpu, sregs->cr4);
 
+	if (sregs->cr4&  X86_CR4_OSXSAVE)
+		update_cpuid(vcpu);
Quoted 6 lines
Quoted 4 lines
  	if (!is_long_mode(vcpu)&&  is_pae(vcpu)) {
  	
  		load_pdptrs(vcpu, vcpu->arch.walk_mmu, vcpu->arch.cr3);
  		mmu_reset_needed = 1;

We really should use kvm_set_crX() here.

Yeah, I suppose we use ops->set_cr4() here because we don't need to all kinds of check and operation for the value(which should already be done by other S/R code), so I just add update_cpuid() here.

--
regards
Yang, Sheng

#3 lore raw
Quoted 11 lines · Sheng Yang
Quoted 6 lines
Quoted 4 lines
   	if (!is_long_mode(vcpu)&&   is_pae(vcpu)) {
   	
   		load_pdptrs(vcpu, vcpu->arch.walk_mmu, vcpu->arch.cr3);
   		mmu_reset_needed = 1;

We really should use kvm_set_crX() here.

Yeah, I suppose we use ops->set_cr4() here because we don't need to all kinds of check and operation for the value(which should already be done by other S/R code), so I just add update_cpuid() here.

IIRC the reason is that there are ordering constraints for kvm_set_crX (and kvm_set_efer). We should do a kvm_set_crs() which sets them all at once.

Signature · 1 line
error compiling committee.c: too many arguments to function