1 files changed, 36 insertions, 0 deletions

diff --git a/arch/mips/kvm/emulate.c b/arch/mips/kvm/emulate.c
index 838d3a6a5b7d..33e132dc7de8 100644
--- a/arch/mips/kvm/emulate.c
+++ b/arch/mips/kvm/emulate.c
@@ -1970,6 +1970,41 @@ enum emulation_result kvm_mips_emulate_bp_exc(unsigned long cause,
         return er;
 }
 
+enum emulation_result kvm_mips_emulate_trap_exc(unsigned long cause,
+                                                uint32_t *opc,
+                                                struct kvm_run *run,
+                                                struct kvm_vcpu *vcpu)
+{
+        struct mips_coproc *cop0 = vcpu->arch.cop0;
+        struct kvm_vcpu_arch *arch = &vcpu->arch;
+        enum emulation_result er = EMULATE_DONE;
+
+        if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
+                /* save old pc */
+                kvm_write_c0_guest_epc(cop0, arch->pc);
+                kvm_set_c0_guest_status(cop0, ST0_EXL);
+
+                if (cause & CAUSEF_BD)
+                        kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
+                else
+                        kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
+
+                kvm_debug("Delivering TRAP @ pc %#lx\n", arch->pc);
+
+                kvm_change_c0_guest_cause(cop0, (0xff),
+                                          (T_TRAP << CAUSEB_EXCCODE));
+
+                /* Set PC to the exception entry point */
+                arch->pc = KVM_GUEST_KSEG0 + 0x180;
+
+        } else {
+                kvm_err("Trying to deliver TRAP when EXL is already set\n");
+                er = EMULATE_FAIL;
+        }
+
+        return er;
+}
+
 /* ll/sc, rdhwr, sync emulation */
 
 #define OPCODE 0xfc000000
@@ -2176,6 +2211,7 @@ enum emulation_result kvm_mips_check_privilege(unsigned long cause,
                 case T_SYSCALL:
                 case T_BREAK:
                 case T_RES_INST:
+                case T_TRAP:
                 case T_MSADIS:
                         break;