Commit 14364656 authored by Avi Kivity's avatar Avi Kivity Committed by Linus Torvalds
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[PATCH] KVM: MMU: Treat user-mode faults as a hint that a page is no longer a page table 



Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
Acked-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 32b35627

drivers/kvm/paging_tmpl.h

+12 −1
Original line number Diff line number Diff line
@@ -271,6 +271,7 @@ static int FNAME(fix_write_pf)(struct kvm_vcpu *vcpu, 
	pt_element_t *guest_ent;

	int writable_shadow;

	gfn_t gfn;

	struct kvm_mmu_page *page;



	if (is_writeble_pte(*shadow_ent))

		return 0;
@@ -303,7 +304,17 @@ static int FNAME(fix_write_pf)(struct kvm_vcpu *vcpu, 
	}



	gfn = walker->gfn;

	if (kvm_mmu_lookup_page(vcpu, gfn)) {



	if (user) {

		/*

		 * Usermode page faults won't be for page table updates.

		 */

		while ((page = kvm_mmu_lookup_page(vcpu, gfn)) != NULL) {

			pgprintk("%s: zap %lx %x\n",

				 __FUNCTION__, gfn, page->role.word);

			kvm_mmu_zap_page(vcpu, page);

		}

	} else if (kvm_mmu_lookup_page(vcpu, gfn)) {

		pgprintk("%s: found shadow page for %lx, marking ro\n",

			 __FUNCTION__, gfn);

		*write_pt = 1;