Paolo Bonzini <pbonzini@xxxxxxxxxx> writes: > Right now, svm_hv_vmcb_dirty_nested_enlightenments has an incorrect > dereference of vmcb->control.reserved_sw before the vmcb is checked > for being non-NULL. The compiler is usually sinking the dereference > after the check; instead of doing this ourselves in the source, > ensure that svm_hv_vmcb_dirty_nested_enlightenments is only called > with a non-NULL VMCB. > > Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > Cc: Vineeth Pillai <viremana@xxxxxxxxxxxxxxxxxxx> > Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> > [Untested for now due to issues with my AMD machine. - Paolo] At least this doesn't seem to break kvm-amd on bare metal, so Tested-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> > --- > arch/x86/kvm/svm/svm.c | 4 ++-- > arch/x86/kvm/svm/svm_onhyperv.h | 2 +- > 2 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c > index 9a6987549e1b..4bcb95bb8ed7 100644 > --- a/arch/x86/kvm/svm/svm.c > +++ b/arch/x86/kvm/svm/svm.c > @@ -1406,8 +1406,6 @@ static int svm_create_vcpu(struct kvm_vcpu *vcpu) > goto error_free_vmsa_page; > } > > - svm_vcpu_init_msrpm(vcpu, svm->msrpm); > - > svm->vmcb01.ptr = page_address(vmcb01_page); > svm->vmcb01.pa = __sme_set(page_to_pfn(vmcb01_page) << PAGE_SHIFT); > > @@ -1419,6 +1417,8 @@ static int svm_create_vcpu(struct kvm_vcpu *vcpu) > svm_switch_vmcb(svm, &svm->vmcb01); > init_vmcb(vcpu); > > + svm_vcpu_init_msrpm(vcpu, svm->msrpm); > + > svm_init_osvw(vcpu); > vcpu->arch.microcode_version = 0x01000065; > > diff --git a/arch/x86/kvm/svm/svm_onhyperv.h b/arch/x86/kvm/svm/svm_onhyperv.h > index 9b9a55abc29f..c53b8bf8d013 100644 > --- a/arch/x86/kvm/svm/svm_onhyperv.h > +++ b/arch/x86/kvm/svm/svm_onhyperv.h > @@ -89,7 +89,7 @@ static inline void svm_hv_vmcb_dirty_nested_enlightenments( > * as we mark it dirty unconditionally towards end of vcpu > * init phase. > */ > - if (vmcb && vmcb_is_clean(vmcb, VMCB_HV_NESTED_ENLIGHTENMENTS) && > + if (vmcb_is_clean(vmcb, VMCB_HV_NESTED_ENLIGHTENMENTS) && > hve->hv_enlightenments_control.msr_bitmap) > vmcb_mark_dirty(vmcb, VMCB_HV_NESTED_ENLIGHTENMENTS); > } -- Vitaly
