KVM: MMU: Track page fault data in struct vcpu

This patch introduces a struct with two new fields in
vcpu_arch for x86:

	* fault.address
	* fault.error_code

This will be used to correctly propagate page faults back
into the guest when we could have either an ordinary page
fault or a nested page fault. In the case of a nested page
fault the fault-address is different from the original
address that should be walked. So we need to keep track
about the real fault-address.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

2 files changed, 12 insertions, 6 deletions

diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h
index 1bf11400ae99..5187dd88019b 100644
--- a/arch/x86/include/asm/kvm_emulate.h
+++ b/arch/x86/include/asm/kvm_emulate.h
@@ -229,7 +229,6 @@ struct x86_emulate_ctxt {
         int exception; /* exception that happens during emulation or -1 */
         u32 error_code; /* error code for exception */
         bool error_code_valid;
-        unsigned long cr2; /* faulted address in case of #PF */
 
         /* decode cache */
         struct decode_cache decode;
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 009a4a1b370e..3fde5b322534 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -239,9 +239,7 @@ struct kvm_mmu {
         void (*set_cr3)(struct kvm_vcpu *vcpu, unsigned long root);
         unsigned long (*get_cr3)(struct kvm_vcpu *vcpu);
         int (*page_fault)(struct kvm_vcpu *vcpu, gva_t gva, u32 err);
-        void (*inject_page_fault)(struct kvm_vcpu *vcpu,
-                                  unsigned long addr,
-                                  u32 error_code);
+        void (*inject_page_fault)(struct kvm_vcpu *vcpu);
         void (*free)(struct kvm_vcpu *vcpu);
         gpa_t (*gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t gva, u32 access,
                             u32 *error);
@@ -288,6 +286,16 @@ struct kvm_vcpu_arch {
         bool tpr_access_reporting;
 
         struct kvm_mmu mmu;
+
+        /*
+         * This struct is filled with the necessary information to propagate a
+         * page fault into the guest
+         */
+        struct {
+                u64      address;
+                unsigned error_code;
+        } fault;
+
         /* only needed in kvm_pv_mmu_op() path, but it's hot so
          * put it here to avoid allocation */
         struct kvm_pv_mmu_op_buffer mmu_op_buffer;
@@ -624,8 +632,7 @@ void kvm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr);
 void kvm_queue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code);
 void kvm_requeue_exception(struct kvm_vcpu *vcpu, unsigned nr);
 void kvm_requeue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code);
-void kvm_inject_page_fault(struct kvm_vcpu *vcpu, unsigned long cr2,
-                           u32 error_code);
+void kvm_inject_page_fault(struct kvm_vcpu *vcpu);
 bool kvm_require_cpl(struct kvm_vcpu *vcpu, int required_cpl);
 
 int kvm_pic_set_irq(void *opaque, int irq, int level);