commit 3778aa970f21b475ca16befcf271078602104fe6
author Matheus Ferst <matheus.ferst@eldorado.org.br> Thu Jul 14 14:23:43 2022 -0300
committer Daniel Henrique Barboza <danielhb413@gmail.com> Mon Jul 18 13:59:43 2022 -0300
tree e4fadc5313d4d2b030495b12f9b05531e2fc34ee
parent 491a25535c99b838772ff961a39762333f0e852f

target/ppc: check tb_env != 0 before printing TBU/TBL/DECR

When using "-machine none", env->tb_env is not allocated, causing the
segmentation fault reported in issue #85 (launchpad bug #811683). To
avoid this problem, check if the pointer != NULL before calling the
methods to print TBU/TBL/DECR.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/85
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220714172343.80539-1-matheus.ferst@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

target/ppc/cpu_init.c

diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c
index 4f2355e..d1493a6 100644
--- a/target/ppc/cpu_init.c
+++ b/target/ppc/cpu_init.c
@@ -7471,17 +7471,15 @@
                  "%08x iidx %d didx %d\n",
                  env->msr, env->spr[SPR_HID0], env->hflags,
                  cpu_mmu_index(env, true), cpu_mmu_index(env, false));
-#if !defined(NO_TIMER_DUMP)
-    qemu_fprintf(f, "TB %08" PRIu32 " %08" PRIu64
 #if !defined(CONFIG_USER_ONLY)
-                 " DECR " TARGET_FMT_lu
-#endif
-                 "\n",
-                 cpu_ppc_load_tbu(env), cpu_ppc_load_tbl(env)
-#if !defined(CONFIG_USER_ONLY)
-                 , cpu_ppc_load_decr(env)
-#endif
-        );
+    if (env->tb_env) {
+        qemu_fprintf(f, "TB %08" PRIu32 " %08" PRIu64
+                     " DECR " TARGET_FMT_lu "\n", cpu_ppc_load_tbu(env),
+                     cpu_ppc_load_tbl(env), cpu_ppc_load_decr(env));
+    }
+#else
+    qemu_fprintf(f, "TB %08" PRIu32 " %08" PRIu64 "\n", cpu_ppc_load_tbu(env),
+                 cpu_ppc_load_tbl(env));
 #endif
     for (i = 0; i < 32; i++) {
         if ((i & (RGPL - 1)) == 0) {

target/ppc/monitor.c

diff --git a/target/ppc/monitor.c b/target/ppc/monitor.c
index 0b805ef..8250b13 100644
--- a/target/ppc/monitor.c
+++ b/target/ppc/monitor.c
@@ -55,6 +55,9 @@
                                     int val)
 {
     CPUArchState *env = mon_get_cpu_env(mon);
+    if (!env->tb_env) {
+        return 0;
+    }
     return cpu_ppc_load_decr(env);
 }
 
@@ -62,6 +65,9 @@
                                    int val)
 {
     CPUArchState *env = mon_get_cpu_env(mon);
+    if (!env->tb_env) {
+        return 0;
+    }
     return cpu_ppc_load_tbu(env);
 }
 
@@ -69,6 +75,9 @@
                                    int val)
 {
     CPUArchState *env = mon_get_cpu_env(mon);
+    if (!env->tb_env) {
+        return 0;
+    }
     return cpu_ppc_load_tbl(env);
 }