On Fri, Aug 26, 2022 at 04:12:21PM -0700,
David Matlack <dmatlack@xxxxxxxxxx> wrote:
> Handle error PFNs in kvm_faultin_pfn() rather than relying on the caller
> to invoke handle_abnormal_pfn() after kvm_faultin_pfn().
> Opportunistically rename kvm_handle_bad_page() to kvm_handle_error_pfn()
> to make it more consistent with is_error_pfn().
>
> This commit moves KVM closer to being able to drop
> handle_abnormal_pfn(), which will reduce the amount of duplicate code in
> the various page fault handlers.
>
> No functional change intended.
>
> Signed-off-by: David Matlack <dmatlack@xxxxxxxxxx>
> ---
> arch/x86/kvm/mmu/mmu.c | 18 ++++++++++++------
> 1 file changed, 12 insertions(+), 6 deletions(-)
>
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index 49dbe274c709..273e1771965c 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -3144,7 +3144,7 @@ static void kvm_send_hwpoison_signal(unsigned long address, struct task_struct *
> send_sig_mceerr(BUS_MCEERR_AR, (void __user *)address, PAGE_SHIFT, tsk);
> }
>
> -static int kvm_handle_bad_page(struct kvm_vcpu *vcpu, gfn_t gfn, kvm_pfn_t pfn)
> +static int kvm_handle_error_pfn(struct kvm_vcpu *vcpu, gfn_t gfn, kvm_pfn_t pfn)
> {
> /*
> * Do not cache the mmio info caused by writing the readonly gfn
> @@ -3165,10 +3165,6 @@ static int kvm_handle_bad_page(struct kvm_vcpu *vcpu, gfn_t gfn, kvm_pfn_t pfn)
> static int handle_abnormal_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault,
> unsigned int access)
> {
> - /* The pfn is invalid, report the error! */
> - if (unlikely(is_error_pfn(fault->pfn)))
> - return kvm_handle_bad_page(vcpu, fault->gfn, fault->pfn);
> -
> if (unlikely(!fault->slot)) {
> gva_t gva = fault->is_tdp ? 0 : fault->addr;
>
> @@ -4185,15 +4181,25 @@ static int __kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
> fault->pfn = __gfn_to_pfn_memslot(slot, fault->gfn, false, NULL,
> fault->write, &fault->map_writable,
> &fault->hva);
> +
> return RET_PF_CONTINUE;
> }
nit: unnecessary code churn.
Otherwise, code looks good to me.
--
Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
