On Wed, Feb 21, 2018 at 06:43:00PM +0100, Andrew Jones wrote:
> On Thu, Feb 15, 2018 at 10:03:05PM +0100, Christoffer Dall wrote:
> > So far this is mostly (see below) a copy of the legacy non-VHE switch
> > function, but we will start reworking these functions in separate
> > directions to work on VHE and non-VHE in the most optimal way in later
> > patches.
> >
> > The only difference after this patch between the VHE and non-VHE run
> > functions is that we omit the branch-predictor variant-2 hardening for
> > QC Falkor CPUs, because this workaround is specific to a series of
> > non-VHE ARMv8.0 CPUs.
> >
> > Reviewed-by: Marc Zyngier <marc.zyngier@xxxxxxx>
> > Signed-off-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx>
> > ---
> >
> > Notes:
> > Changes since v3:
> > - Added BUG() to 32-bit ARM VHE run function
> > - Omitted QC Falkor BP Hardening functionality from VHE-specific
> > function
> >
> > Changes since v2:
> > - Reworded commit message
> >
> > Changes since v1:
> > - Rename kvm_vcpu_run to kvm_vcpu_run_vhe and rename __kvm_vcpu_run to
> > __kvm_vcpu_run_nvhe
> > - Removed stray whitespace line
> >
> > arch/arm/include/asm/kvm_asm.h | 5 ++-
> > arch/arm/kvm/hyp/switch.c | 2 +-
> > arch/arm64/include/asm/kvm_asm.h | 4 ++-
> > arch/arm64/kvm/hyp/switch.c | 66 +++++++++++++++++++++++++++++++++++++++-
> > virt/kvm/arm/arm.c | 5 ++-
> > 5 files changed, 77 insertions(+), 5 deletions(-)
> >
>
> ...
>
> > diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
> > index 2062d9357971..5bd879c78951 100644
> > --- a/virt/kvm/arm/arm.c
> > +++ b/virt/kvm/arm/arm.c
> > @@ -736,7 +736,10 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
> > if (has_vhe())
> > kvm_arm_vhe_guest_enter();
> >
> > - ret = kvm_call_hyp(__kvm_vcpu_run, vcpu);
> > + if (has_vhe())
> > + ret = kvm_vcpu_run_vhe(vcpu);
> > + else
> > + ret = kvm_call_hyp(__kvm_vcpu_run_nvhe, vcpu);
> >
> > if (has_vhe())
> > kvm_arm_vhe_guest_exit();
>
> We can combine these has_vhe()'s
>
> if (has_vhe()) {
> kvm_arm_vhe_guest_enter();
> ret = kvm_vcpu_run_vhe(vcpu);
> kvm_arm_vhe_guest_exit();
> } else
> ret = kvm_call_hyp(__kvm_vcpu_run_nvhe, vcpu);
Maybe even do a cleanup patch that removes
kvm_arm_vhe_guest_enter/exit by putting the daif
masking/restoring directly into kvm_vcpu_run_vhe()?
Thanks,
drew
