Commit 7d945312 authored by Ben Gardon's avatar Ben Gardon Committed by Paolo Bonzini
Browse files

kvm: x86/mmu: Remove disallowed_hugepage_adjust shadow_walk_iterator arg 

In order to avoid creating executable hugepages in the TDP MMU PF
handler, remove the dependency between disallowed_hugepage_adjust and
the shadow_walk_iterator. This will open the function up to being used
by the TDP MMU PF handler in a future patch.

Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell
machine. This series introduced no new failures.

This series can be viewed in Gerrit at:
	https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538



Signed-off-by: default avatarBen Gardon <bgardon@google.com>
Message-Id: <20201014182700.2888246-10-bgardon@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent faaf05b0

arch/x86/kvm/mmu/mmu.c

+7 −6
Original line number Diff line number Diff line
@@ -2818,13 +2818,12 @@ static int kvm_mmu_hugepage_adjust(struct kvm_vcpu *vcpu, gfn_t gfn, 
	return level;

}



static void disallowed_hugepage_adjust(struct kvm_shadow_walk_iterator it,

				       gfn_t gfn, kvm_pfn_t *pfnp, int *levelp)

static void disallowed_hugepage_adjust(u64 spte, gfn_t gfn, int cur_level,

				       kvm_pfn_t *pfnp, int *levelp)

{

	int level = *levelp;

	u64 spte = *it.sptep;



	if (it.level == level && level > PG_LEVEL_4K &&

	if (cur_level == level && level > PG_LEVEL_4K &&

	    is_shadow_present_pte(spte) &&

	    !is_large_pte(spte)) {

		/*
@@ -2834,7 +2833,8 @@ static void disallowed_hugepage_adjust(struct kvm_shadow_walk_iterator it, 
		 * patching back for them into pfn the next 9 bits of

		 * the address.

		 */

		u64 page_mask = KVM_PAGES_PER_HPAGE(level) - KVM_PAGES_PER_HPAGE(level - 1);

		u64 page_mask = KVM_PAGES_PER_HPAGE(level) -

				KVM_PAGES_PER_HPAGE(level - 1);

		*pfnp |= gfn & page_mask;

		(*levelp)--;

	}
@@ -2867,7 +2867,8 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, 
		 * large page, as the leaf could be executable.

		 */

		if (nx_huge_page_workaround_enabled)

			disallowed_hugepage_adjust(it, gfn, &pfn, &level);

			disallowed_hugepage_adjust(*it.sptep, gfn, it.level,

						   &pfn, &level);



		base_gfn = gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1);

		if (it.level == level)

arch/x86/kvm/mmu/paging_tmpl.h

+2 −1
Original line number Diff line number Diff line
@@ -695,7 +695,8 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, gpa_t addr, 
		 * large page, as the leaf could be executable.

		 */

		if (nx_huge_page_workaround_enabled)

			disallowed_hugepage_adjust(it, gw->gfn, &pfn, &level);

			disallowed_hugepage_adjust(*it.sptep, gw->gfn, it.level,

						   &pfn, &level);



		base_gfn = gw->gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1);

		if (it.level == level)

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