linux-kernel - [PATCH 4.9 16/31] KVM: x86: simplify ept

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20191115062016.837160389@linuxfoundation.org>
Date:   Fri, 15 Nov 2019 14:20:45 +0800
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Paolo Bonzini <pbonzini@...hat.com>,
        David Hildenbrand <david@...hat.com>,
        Radim Krčmář <rkrcmar@...hat.com>,
        Ben Hutchings <ben@...adent.org.uk>
Subject: [PATCH 4.9 16/31] KVM: x86: simplify ept_misconfig

From: Paolo Bonzini <pbonzini@...hat.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@...hat.com>
Reviewed-by: David Hildenbrand <david@...hat.com>
Signed-off-by: Radim Krčmář <rkrcmar@...hat.com>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.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);