hw/intc/arm_gicv3_its: Fix return codes in process_its_cmd()

Fix process_its_cmd() to consistently return CMD_STALL for
memory errors and CMD_CONTINUE for parameter errors, as
we claim in the comments that we do.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220111171048.3545974-7-peter.maydell@linaro.org

diff --git a/hw/intc/arm_gicv3_its.c b/hw/intc/arm_gicv3_its.c
index 10901a5e709296dd55e8d7ab1d180b8e248be858..0929116c0feabbced754419b8cd03a6fed26f1ad 100644 (file)
--- a/hw/intc/arm_gicv3_its.c
+++ b/hw/intc/arm_gicv3_its.c
@@ -248,7 +248,6 @@ static ItsCmdResult process_its_cmd(GICv3ITSState *s, uint64_t value,
     bool ite_valid = false;
     uint64_t cte = 0;
     bool cte_valid = false;
-    ItsCmdResult result = CMD_STALL;
     uint64_t rdbase;
 
     if (cmd == NONE) {
@@ -262,7 +261,7 @@ static ItsCmdResult process_its_cmd(GICv3ITSState *s, uint64_t value,
     }
 
     if (res != MEMTX_OK) {
-        return result;
+        return CMD_STALL;
     }
 
     eventid = (value & EVENTID_MASK);
@@ -270,7 +269,7 @@ static ItsCmdResult process_its_cmd(GICv3ITSState *s, uint64_t value,
     dte = get_dte(s, devid, &res);
 
     if (res != MEMTX_OK) {
-        return result;
+        return CMD_STALL;
     }
     dte_valid = FIELD_EX64(dte, DTE, VALID);
 
@@ -280,7 +279,7 @@ static ItsCmdResult process_its_cmd(GICv3ITSState *s, uint64_t value,
         ite_valid = get_ite(s, eventid, dte, &icid, &pIntid, &res);
 
         if (res != MEMTX_OK) {
-            return result;
+            return CMD_STALL;
         }
 
         if (ite_valid) {
@@ -288,14 +287,14 @@ static ItsCmdResult process_its_cmd(GICv3ITSState *s, uint64_t value,
         }
 
         if (res != MEMTX_OK) {
-            return result;
+            return CMD_STALL;
         }
     } else {
         qemu_log_mask(LOG_GUEST_ERROR,
                       "%s: invalid command attributes: "
                       "invalid dte: %"PRIx64" for %d (MEM_TX: %d)\n",
                       __func__, dte, devid, res);
-        return result;
+        return CMD_CONTINUE;
     }
 
 
@@ -307,7 +306,7 @@ static ItsCmdResult process_its_cmd(GICv3ITSState *s, uint64_t value,
         qemu_log_mask(LOG_GUEST_ERROR,
                       "%s: invalid command attributes: devid %d>=%d",
                       __func__, devid, s->dt.num_ids);
-
+        return CMD_CONTINUE;
     } else if (!dte_valid || !ite_valid || !cte_valid) {
         qemu_log_mask(LOG_GUEST_ERROR,
                       "%s: invalid command attributes: "
@@ -316,11 +315,13 @@ static ItsCmdResult process_its_cmd(GICv3ITSState *s, uint64_t value,
                       dte_valid ? "valid" : "invalid",
                       ite_valid ? "valid" : "invalid",
                       cte_valid ? "valid" : "invalid");
+        return CMD_CONTINUE;
     } else if (eventid >= num_eventids) {
         qemu_log_mask(LOG_GUEST_ERROR,
                       "%s: invalid command attributes: eventid %d >= %"
                       PRId64 "\n",
                       __func__, eventid, num_eventids);
+        return CMD_CONTINUE;
     } else {
         /*
          * Current implementation only supports rdbase == procnum
@@ -329,7 +330,7 @@ static ItsCmdResult process_its_cmd(GICv3ITSState *s, uint64_t value,
         rdbase = FIELD_EX64(cte, CTE, RDBASE);
 
         if (rdbase >= s->gicv3->num_cpu) {
-            return result;
+            return CMD_CONTINUE;
         }
 
         if ((cmd == CLEAR) || (cmd == DISCARD)) {
@@ -341,11 +342,10 @@ static ItsCmdResult process_its_cmd(GICv3ITSState *s, uint64_t value,
         if (cmd == DISCARD) {
             IteEntry ite = {};
             /* remove mapping from interrupt translation table */
-            result = update_ite(s, eventid, dte, ite) ? CMD_CONTINUE : CMD_STALL;
+            return update_ite(s, eventid, dte, ite) ? CMD_CONTINUE : CMD_STALL;
         }
+        return CMD_CONTINUE;
     }
-
-    return result;
 }
 
 static ItsCmdResult process_mapti(GICv3ITSState *s, uint64_t value,