Re: [PATCH v11 06/35] KVM: x86/mmu: Pass around full 64-bit error code for KVM page faults

From: Paolo Bonzini
Date: Mon Feb 12 2024 - 05:01:17 EST


On Tue, Feb 6, 2024 at 9:52 PM Sean Christopherson <seanjc@xxxxxxxxxx> wrote:
>
> On Sat, Dec 30, 2023, Michael Roth wrote:
> > In some cases the full 64-bit error code for the KVM page fault will be
> > needed to determine things like whether or not a fault was for a private
> > or shared guest page, so update related code to accept the full 64-bit
> > value so it can be plumbed all the way through to where it is needed.
> >
> > The accessors of fault->error_code are changed as follows:
> >
> > - FNAME(page_fault): change to explicitly use lower_32_bits() since that
> > is no longer done in kvm_mmu_page_fault()
> > - kvm_mmu_page_fault(): explicit mask with PFERR_RSVD_MASK,
> > PFERR_NESTED_GUEST_PAGE
> > - mmutrace: changed u32 -> u64
> >
> > Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
> > Link: https://lore.kernel.org/kvm/20230612042559.375660-1-michael.roth@xxxxxxx/T/#mbd0b20c9a2cf50319d5d2a27b63f73c772112076
> > [mdr: drop references/changes to code not in current gmem tree, update
> > commit message]
> > Signed-off-by: Michael Roth <michael.roth@xxxxxxx>
>
> I assume Isaku is the original author? If so, that's missing from this patch.

The root of this patch seem to be in a reply to "KVM: x86: Add
'fault_is_private' x86 op"
(https://patchew.org/linux/20230220183847.59159-1-michael.roth@xxxxxxx/20230220183847.59159-2-michael.roth@xxxxxxx/),
so yes.

Paolo