Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit e5a4c8ca authored by Avi Kivity's avatar Avi Kivity
Browse files

KVM: MMU: Implement guest page fault bypass for nonpae 



I spent an hour worrying why I see so many guest page faults on FC6 i386.
Turns out bypass wasn't implemented for nonpae.  Implement it so it doesn't
happen again.

Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent 26e5215f

drivers/kvm/paging_tmpl.h

+6 −3
Original line number Diff line number Diff line
@@ -486,19 +486,22 @@ static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr) 
static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu,

				 struct kvm_mmu_page *sp)

{

	int i;

	int i, offset = 0;

	pt_element_t *gpt;

	struct page *page;



	if (sp->role.metaphysical || PTTYPE == 32) {

	if (sp->role.metaphysical

	    || (PTTYPE == 32 && sp->role.level > PT_PAGE_TABLE_LEVEL)) {

		nonpaging_prefetch_page(vcpu, sp);

		return;

	}



	if (PTTYPE == 32)

		offset = sp->role.quadrant << PT64_LEVEL_BITS;

	page = gfn_to_page(vcpu->kvm, sp->gfn);

	gpt = kmap_atomic(page, KM_USER0);

	for (i = 0; i < PT64_ENT_PER_PAGE; ++i)

		if (is_present_pte(gpt[i]))

		if (is_present_pte(gpt[offset + i]))

			sp->spt[i] = shadow_trap_nonpresent_pte;

		else

			sp->spt[i] = shadow_notrap_nonpresent_pte;