[PATCH v3 05/41] KVM: arm64: Move HCR_INT_OVERRIDE to default HCR_EL2 guest flag

Christoffer Dall christoffer.dall at linaro.org
Tue Feb 13 13:47:54 PST 2018

On Fri, Feb 09, 2018 at 11:38:50AM +0000, Julien Grall wrote:
> Hi,
> On 01/12/2018 12:07 PM, Christoffer Dall wrote:
> >From: Shih-Wei Li <shihwei at cs.columbia.edu>
> >
> >We always set the IMO and FMO bits in the HCR_EL2 when running the
> >guest, regardless if we use the vgic or not.  By moving these flags to
> >HCR_GUEST_FLAGS we can avoid one of the extra save/restore operations of
> >HCR_EL2 in the world switch code, and we can also soon get rid of the
> >other one.
> >
> >This is safe, because even though the IMO and FMO bits control both
> >taking the interrupts to EL2 and remapping ICC_*_EL1 to ICV_*_EL1
> >executed at EL1, as long as we ensure that these bits are clear when
> >running the EL1 host, as defined in the HCR_HOST_[VHE_]FLAGS, we're OK.
> NIT: I was a bit confused by the end of the sentence because HCR_HOST_FLAGS
> define does not seem to exist.

True, that was nonsense.

I have reworded it slightly.


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