[PATCH 4.9 16/31] KVM: x86: simplify ept_misconfig

Greg Kroah-Hartman
2019-11-15T06:23:54Z

From: Paolo Bonzini <pbonzini@redhat.com>

commit e08d26f0712532c79b5ba6200862eaf2036f8df6 upstream.

Calling handle_mmio_page_fault() has been unnecessary since commit
e9ee956e311d ("KVM: x86: MMU: Move handle_mmio_page_fault() call to
kvm_mmu_page_fault()", 2016-02-22).

handle_mmio_page_fault() can now be made static.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/kvm/mmu.c | 19 ++++++++++++++++++-
arch/x86/kvm/mmu.h | 17 -----------------
arch/x86/kvm/vmx.c | 13 +++----------
3 files changed, 21 insertions(+), 28 deletions(-)

--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -3383,7 +3383,23 @@ exit:
return reserved;
}

-int handle_mmio_page_fault(struct kvm_vcpu *vcpu, u64 addr, bool direct)
+/*
+ * Return values of handle_mmio_page_fault:
+ * RET_MMIO_PF_EMULATE: it is a real mmio page fault, emulate the instruction
+ * directly.
+ * RET_MMIO_PF_INVALID: invalid spte is detected then let the real page
+ * fault path update the mmio spte.
+ * RET_MMIO_PF_RETRY: let CPU fault again on the address.
+ * RET_MMIO_PF_BUG: a bug was detected (and a WARN was printed).
+ */
+enum {
+ RET_MMIO_PF_EMULATE = 1,
+ RET_MMIO_PF_INVALID = 2,
+ RET_MMIO_PF_RETRY = 0,
+ RET_MMIO_PF_BUG = -1
+};
+
+static int handle_mmio_page_fault(struct kvm_vcpu *vcpu, u64 addr, bool direct)
{
u64 spte;
bool reserved;
@@ -4520,6 +4536,7 @@ int kvm_mmu_page_fault(struct kvm_vcpu *
return 1;
if (r < 0)
return r;
+ /* Must be RET_MMIO_PF_INVALID. */
}

r = vcpu->arch.mmu.page_fault(vcpu, cr2, error_code, false);
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -56,23 +56,6 @@ void kvm_mmu_set_mmio_spte_mask(u64 mmio
void
reset_shadow_zero_bits_mask(struct kvm_vcpu *vcpu, struct kvm_mmu *context);

-/*
- * Return values of handle_mmio_page_fault:
- * RET_MMIO_PF_EMULATE: it is a real mmio page fault, emulate the instruction
- * directly.
- * RET_MMIO_PF_INVALID: invalid spte is detected then let the real page
- * fault path update the mmio spte.
- * RET_MMIO_PF_RETRY: let CPU fault again on the address.
- * RET_MMIO_PF_BUG: a bug was detected (and a WARN was printed).
- */
-enum {
- RET_MMIO_PF_EMULATE = 1,
- RET_MMIO_PF_INVALID = 2,
- RET_MMIO_PF_RETRY = 0,
- RET_MMIO_PF_BUG = -1
-};
-
-int handle_mmio_page_fault(struct kvm_vcpu *vcpu, u64 addr, bool direct);
void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu);
void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly);
bool kvm_can_do_async_pf(struct kvm_vcpu *vcpu);
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6556,16 +6556,9 @@ static int handle_ept_misconfig(struct k
NULL, 0) == EMULATE_DONE;
}

- ret = handle_mmio_page_fault(vcpu, gpa, true);
- if (likely(ret == RET_MMIO_PF_EMULATE))
- return x86_emulate_instruction(vcpu, gpa, 0, NULL, 0) ==
- EMULATE_DONE;
-
- if (unlikely(ret == RET_MMIO_PF_INVALID))
- return kvm_mmu_page_fault(vcpu, gpa, 0, NULL, 0);
-
- if (unlikely(ret == RET_MMIO_PF_RETRY))
- return 1;
+ ret = kvm_mmu_page_fault(vcpu, gpa, PFERR_RSVD_MASK, NULL, 0);
+ if (ret >= 0)
+ return ret;

/* It is the real ept misconfig */
WARN_ON(1);