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-rw-r--r--target-arm/op_helper.c22
1 files changed, 14 insertions, 8 deletions
diff --git a/target-arm/op_helper.c b/target-arm/op_helper.c
index fb90676bd5..b28f694d00 100644
--- a/target-arm/op_helper.c
+++ b/target-arm/op_helper.c
@@ -17,7 +17,7 @@
  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  */
 #include "cpu.h"
-#include "helper.h"
+#include "exec/helper-proto.h"
 #include "internals.h"
 
 #define SIGNBIT (uint32_t)0x80000000
@@ -386,11 +386,13 @@ void HELPER(msr_i_pstate)(CPUARMState *env, uint32_t op, uint32_t imm)
 
 void HELPER(exception_return)(CPUARMState *env)
 {
-    uint32_t spsr = env->banked_spsr[0];
+    int cur_el = arm_current_pl(env);
+    unsigned int spsr_idx = aarch64_banked_spsr_index(cur_el);
+    uint32_t spsr = env->banked_spsr[spsr_idx];
     int new_el, i;
 
     if (env->pstate & PSTATE_SP) {
-        env->sp_el[1] = env->xregs[31];
+        env->sp_el[cur_el] = env->xregs[31];
     } else {
         env->sp_el[0] = env->xregs[31];
     }
@@ -398,6 +400,7 @@ void HELPER(exception_return)(CPUARMState *env)
     env->exclusive_addr = -1;
 
     if (spsr & PSTATE_nRW) {
+        /* TODO: We currently assume EL1/2/3 are running in AArch64.  */
         env->aarch64 = 0;
         new_el = 0;
         env->uncached_cpsr = 0x10;
@@ -406,11 +409,14 @@ void HELPER(exception_return)(CPUARMState *env)
             env->regs[i] = env->xregs[i];
         }
 
-        env->regs[15] = env->elr_el1 & ~0x1;
+        env->regs[15] = env->elr_el[1] & ~0x1;
     } else {
         new_el = extract32(spsr, 2, 2);
-        if (new_el > 1) {
-            /* Return to unimplemented EL */
+        if (new_el > cur_el
+            || (new_el == 2 && !arm_feature(env, ARM_FEATURE_EL2))) {
+            /* Disallow return to an EL which is unimplemented or higher
+             * than the current one.
+             */
             goto illegal_return;
         }
         if (extract32(spsr, 1, 1)) {
@@ -424,7 +430,7 @@ void HELPER(exception_return)(CPUARMState *env)
         env->aarch64 = 1;
         pstate_write(env, spsr);
         env->xregs[31] = env->sp_el[new_el];
-        env->pc = env->elr_el1;
+        env->pc = env->elr_el[cur_el];
     }
 
     return;
@@ -438,7 +444,7 @@ illegal_return:
      * no change to exception level, execution state or stack pointer
      */
     env->pstate |= PSTATE_IL;
-    env->pc = env->elr_el1;
+    env->pc = env->elr_el[cur_el];
     spsr &= PSTATE_NZCV | PSTATE_DAIF;
     spsr |= pstate_read(env) & ~(PSTATE_NZCV | PSTATE_DAIF);
     pstate_write(env, spsr);