On Wed, May 8, 2019 at 2:18 PM Aaron Lewis <aaronlewis@xxxxxxxxxx> wrote: > > From: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> > Date: Wed, May 8, 2019 at 12:55 PM > To: Aaron Lewis > Cc: Peter Shier, Paolo Bonzini, <rkrcmar@xxxxxxxxxx>, Jim Mattson, > Marc Orr, <kvm@xxxxxxxxxxxxxxx> > > > Aaron Lewis <aaronlewis@xxxxxxxxxx> writes: > > > > > From: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> > > > Date: Fri, May 3, 2019 at 3:25 AM > > > To: Aaron Lewis > > > Cc: Peter Shier, <pbonzini@xxxxxxxxxx>, <rkrcmar@xxxxxxxxxx>, > > > <jmattson@xxxxxxxxxx>, <marcorr@xxxxxxxxxx>, <kvm@xxxxxxxxxxxxxxx> > > > > > >> Aaron Lewis <aaronlewis@xxxxxxxxxx> writes: > > >> > > >> > Move call to nested_enable_evmcs until after free_nested() is complete. > > >> > > > >> > Signed-off-by: Aaron Lewis <aaronlewis@xxxxxxxxxx> > > >> > Reviewed-by: Marc Orr <marcorr@xxxxxxxxxx> > > >> > Reviewed-by: Peter Shier <pshier@xxxxxxxxxx> > > >> > --- > > >> > arch/x86/kvm/vmx/nested.c | 6 +++--- > > >> > 1 file changed, 3 insertions(+), 3 deletions(-) > > >> > > > >> > diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c > > >> > index 081dea6e211a..3b39c60951ac 100644 > > >> > --- a/arch/x86/kvm/vmx/nested.c > > >> > +++ b/arch/x86/kvm/vmx/nested.c > > >> > @@ -5373,9 +5373,6 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu, > > >> > if (kvm_state->format != 0) > > >> > return -EINVAL; > > >> > > > >> > - if (kvm_state->flags & KVM_STATE_NESTED_EVMCS) > > >> > - nested_enable_evmcs(vcpu, NULL); > > >> > - > > >> > if (!nested_vmx_allowed(vcpu)) > > >> > return kvm_state->vmx.vmxon_pa == -1ull ? 0 : -EINVAL; > > >> > > > >> > @@ -5417,6 +5414,9 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu, > > >> > if (kvm_state->vmx.vmxon_pa == -1ull) > > >> > return 0; > > >> > > > >> > + if (kvm_state->flags & KVM_STATE_NESTED_EVMCS) > > >> > + nested_enable_evmcs(vcpu, NULL); > > >> > + > > >> > vmx->nested.vmxon_ptr = kvm_state->vmx.vmxon_pa; > > >> > ret = enter_vmx_operation(vcpu); > > >> > if (ret) > > >> > > >> nested_enable_evmcs() doesn't do much, actually, in case it was > > >> previously enabled it doesn't do anything and in case it wasn't ordering > > >> with free_nested() (where you're aiming at nested_release_evmcs() I > > >> would guess) shouldn't matter. So could you please elaborate (better in > > >> the commit message) why do we need this re-ordered? My guess is that > > >> you'd like to perform checks for e.g. 'vmx.vmxon_pa == -1ull' before > > >> we actually start doing any changes but let's clarify that. > > >> > > >> Thanks! > > >> > > >> -- > > >> Vitaly > > > > > > There are two reasons for doing this: > > > 1. We don't want to set new state if we are going to leave nesting and > > > exit the function (ie: vmx.vmxon_pa = -1), like you pointed out. > > > 2. To be more future proof, we don't want to set new state before > > > tearing down state. This could cause conflicts down the road. > > > > > > I can add this to the commit message if there are no objections to > > > these points. > > > > Sounds good to me, please do. Thanks! > > > > -- > > Vitaly > > Here is the updated patch: > > > Move call to nested_enable_evmcs until after free_nested() is > complete. There are two reasons for doing this: > 1. We don't want to set new state if we are going to leave nesting and > exit the function (ie: vmx.vmxon_pa = -1). > 2. To be more future proof, we don't want to set new state before > tearing down state. This could cause conflicts down the road. > > Signed-off-by: Aaron Lewis <aaronlewis@xxxxxxxxxx> > Reviewed-by: Marc Orr <marcorr@xxxxxxxxxx> > Reviewed-by: Peter Shier <pshier@xxxxxxxxxx> > --- > arch/x86/kvm/vmx/nested.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c > index fe5814df5149..6ecc301df874 100644 > --- a/arch/x86/kvm/vmx/nested.c > +++ b/arch/x86/kvm/vmx/nested.c > @@ -5373,9 +5373,6 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu, > if (kvm_state->format != 0) > return -EINVAL; > > - if (kvm_state->flags & KVM_STATE_NESTED_EVMCS) > - nested_enable_evmcs(vcpu, NULL); > - > if (!nested_vmx_allowed(vcpu)) > return kvm_state->vmx.vmxon_pa == -1ull ? 0 : -EINVAL; > > @@ -5417,6 +5414,9 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu, > if (kvm_state->vmx.vmxon_pa == -1ull) > return 0; > > + if (kvm_state->flags & KVM_STATE_NESTED_EVMCS) > + nested_enable_evmcs(vcpu, NULL); > + > vmx->nested.vmxon_ptr = kvm_state->vmx.vmxon_pa; > ret = enter_vmx_operation(vcpu); > if (ret) Hi Vitaly, Does this update look good or are any other changes needed? Thanks, Aaron
