>>> On 2/3/2016 at 04:18 PM, Nadav Amit <nadav.a...@gmail.com> wrote: > Oops. > > Anyhow, I see my patch has done a similar change in init_vmcb() , so you may > want to revert it as well. > > Nadav > > Bruce Rogers <brog...@suse.com> wrote: > >> Commit d28bc9dd25ce reversed the order of two lines which initialize cr0, >> allowing the current (old) cr0 value to mess up vcpu initialization. >> This was observed in the checks for cr0 X86_CR0_WP bit in the context of >> kvm_mmu_reset_context(). Besides, setting vcpu->arch.cr0 after vmx_set_cr0() >> is completely redundant. Change the order back to ensure proper vcpu >> intiialization. >> >> Signed-off-by: Bruce Rogers <brog...@suse.com> >> --- >> arch/x86/kvm/vmx.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c >> index e2951b6..21507b4 100644 >> --- a/arch/x86/kvm/vmx.c >> +++ b/arch/x86/kvm/vmx.c >> @@ -4993,8 +4993,8 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool > init_event) >> vmcs_write16(VIRTUAL_PROCESSOR_ID, vmx->vpid); >> >> cr0 = X86_CR0_NW | X86_CR0_CD | X86_CR0_ET; >> - vmx_set_cr0(vcpu, cr0); /* enter rmode */ >> vmx->vcpu.arch.cr0 = cr0; >> + vmx_set_cr0(vcpu, cr0); /* enter rmode */ >> vmx_set_cr4(vcpu, 0); >> vmx_set_efer(vcpu, 0); >> vmx_fpu_activate(vcpu); >> -- >> 1.9.0 >
I had not pursued this as the initial problem I was chasing ended up including some undefined behavior. Since, I've run into another failure which this patch addresses (ovmf based booting with vcpu count >1 on older hardware), so I'll resend this one patch with updated info. Also, it seems to me that the init_vmcb() svm issue Nadav mentioned is no longer an issue in the current master branch so I won't be addressing that. Bruce
