KVM: x86: Push potential exception error code on task switches

When a fault triggers a task switch, the error code, if existent, has to
be pushed on the new task's stack. Implement the missing bits.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

3 files changed, 5 insertions, 2 deletions

diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h
index a1319c82050e..0b2729bf2070 100644
--- a/arch/x86/include/asm/kvm_emulate.h
+++ b/arch/x86/include/asm/kvm_emulate.h
@@ -230,6 +230,7 @@ int x86_emulate_insn(struct x86_emulate_ctxt *ctxt,
                      struct x86_emulate_ops *ops);
 int emulator_task_switch(struct x86_emulate_ctxt *ctxt,
                          struct x86_emulate_ops *ops,
-                         u16 tss_selector, int reason);
+                         u16 tss_selector, int reason,
+                         bool has_error_code, u32 error_code);
 
 #endif /* _ASM_X86_KVM_X86_EMULATE_H */
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 5d5e0a9afcf2..3602728d54de 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -595,7 +595,8 @@ int emulator_set_dr(struct x86_emulate_ctxt *ctxt, int dr,
 void kvm_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg);
 int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector, int seg);
 
-int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason);
+int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason,
+                    bool has_error_code, u32 error_code);
 
 void kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0);
 void kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3);
diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 1d91d05f9368..0e831059ac5a 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -244,6 +244,7 @@ struct __attribute__ ((__packed__)) vmcb {
 
 #define SVM_EXITINFOSHIFT_TS_REASON_IRET 36
 #define SVM_EXITINFOSHIFT_TS_REASON_JMP 38
+#define SVM_EXITINFOSHIFT_TS_HAS_ERROR_CODE 44
 
 #define SVM_EXIT_READ_CR0       0x000
 #define SVM_EXIT_READ_CR3       0x003