[PATCH] Fix SVM longmode guests

[PATCH] Fix SVM longmode guests

[Zachary Amsden]

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In recent testing, I discovered guests failed to boot on my AMD box.  
Bisecting revealed an EFER related change caused the problem; here is 
the fix.

Cheers,

Zach

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Fix 64-bit guests on SVM.

Must set VCPU register to be the guest notion of EFER even if that
setting is not valid on hardware.  This was masked by the set in
set_efer until 7657fd5ace88e8092f5f3a84117e093d7b893f26 broke that.
Fix is simply to set the VCPU register before stripping bits.

Signed-off-by: Zachary Amsden <zamsden@redhat.com>

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 100bd4b..a05b63f 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -285,11 +285,11 @@ static inline void flush_guest_tlb(struct kvm_vcpu *vcpu)
 
 static void svm_set_efer(struct kvm_vcpu *vcpu, u64 efer)
 {
+	vcpu->arch.efer = efer;
 	if (!npt_enabled && !(efer & EFER_LMA))
 		efer &= ~EFER_LME;
 
 	to_svm(vcpu)->vmcb->save.efer = efer | EFER_SVME;
-	vcpu->arch.efer = efer;
 }
 
 static int is_external_interrupt(u32 info)

Re: [PATCH] Fix SVM longmode guests

[Avi Kivity]

On 05/27/2010 04:09 AM, Zachary Amsden wrote:
> In recent testing, I discovered guests failed to boot on my AMD box.  
> Bisecting revealed an EFER related change caused the problem; here is 
> the fix.
>

Yikes, applied, thanks.

-- 
error compiling committee.c: too many arguments to function