[PATCH v2 3/4] target/ppc: Make checkstop actually stop the system

[Nicholas Piggin <npiggin@gmail.com>]

checkstop state does not halt the system, interrupts continue to be
serviced, and other CPUs run.

Stop the machine with vm_stop(), and print a register dump too.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
Since v1:
- Fix loop exit so it stops on the attn instruction, rather than
  after it.

 target/ppc/excp_helper.c | 34 ++++++++++++++++++++--------------
 1 file changed, 20 insertions(+), 14 deletions(-)

diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
index 5beda973ce..28d8a9b212 100644
--- a/target/ppc/excp_helper.c
+++ b/target/ppc/excp_helper.c
@@ -19,6 +19,7 @@
 #include "qemu/osdep.h"
 #include "qemu/main-loop.h"
 #include "qemu/log.h"
+#include "sysemu/runstate.h"
 #include "cpu.h"
 #include "exec/exec-all.h"
 #include "internal.h"
@@ -186,19 +187,24 @@ static void ppc_excp_debug_sw_tlb(CPUPPCState *env, int excp)
              env->error_code);
 }
 
-static void powerpc_checkstop(CPUPPCState *env)
+static void powerpc_checkstop(CPUPPCState *env, const char *reason)
 {
     CPUState *cs = env_cpu(env);
 
-    /* Machine check exception is not enabled. Enter checkstop state. */
-    fprintf(stderr, "Machine check while not allowed. "
-            "Entering checkstop state\n");
+    vm_stop(RUN_STATE_GUEST_PANICKED);
+
+    fprintf(stderr, "Entering checkstop state: %s\n", reason);
+    cpu_dump_state(cs, stderr, CPU_DUMP_FPU | CPU_DUMP_CCOP);
     if (qemu_log_separate()) {
-        qemu_log("Machine check while not allowed. "
-                 "Entering checkstop state\n");
+        FILE *logfile = qemu_log_trylock();
+        if (logfile) {
+            fprintf(logfile, "Entering checkstop state: %s\n", reason);
+            cpu_dump_state(cs, logfile, CPU_DUMP_FPU | CPU_DUMP_CCOP);
+            qemu_log_unlock(logfile);
+        }
     }
-    cs->halted = 1;
-    cpu_interrupt_exittb(cs);
+
+    cpu_loop_exit_noexc(cs);
 }
 
 #if defined(TARGET_PPC64)
@@ -483,7 +489,7 @@ static void powerpc_excp_40x(PowerPCCPU *cpu, int excp)
         break;
     case POWERPC_EXCP_MCHECK:    /* Machine check exception                  */
         if (!FIELD_EX64(env->msr, MSR, ME)) {
-            powerpc_checkstop(env);
+            powerpc_checkstop(env, "machine check with MSR[ME]=0");
         }
         /* machine check exceptions don't have ME set */
         new_msr &= ~((target_ulong)1 << MSR_ME);
@@ -602,7 +608,7 @@ static void powerpc_excp_6xx(PowerPCCPU *cpu, int excp)
         break;
     case POWERPC_EXCP_MCHECK:    /* Machine check exception                  */
         if (!FIELD_EX64(env->msr, MSR, ME)) {
-            powerpc_checkstop(env);
+            powerpc_checkstop(env, "machine check with MSR[ME]=0");
         }
         /* machine check exceptions don't have ME set */
         new_msr &= ~((target_ulong)1 << MSR_ME);
@@ -763,7 +769,7 @@ static void powerpc_excp_7xx(PowerPCCPU *cpu, int excp)
     switch (excp) {
     case POWERPC_EXCP_MCHECK:    /* Machine check exception                  */
         if (!FIELD_EX64(env->msr, MSR, ME)) {
-            powerpc_checkstop(env);
+            powerpc_checkstop(env, "machine check with MSR[ME]=0");
         }
         /* machine check exceptions don't have ME set */
         new_msr &= ~((target_ulong)1 << MSR_ME);
@@ -936,7 +942,7 @@ static void powerpc_excp_74xx(PowerPCCPU *cpu, int excp)
     switch (excp) {
     case POWERPC_EXCP_MCHECK:    /* Machine check exception                  */
         if (!FIELD_EX64(env->msr, MSR, ME)) {
-            powerpc_checkstop(env);
+            powerpc_checkstop(env, "machine check with MSR[ME]=0");
         }
         /* machine check exceptions don't have ME set */
         new_msr &= ~((target_ulong)1 << MSR_ME);
@@ -1119,7 +1125,7 @@ static void powerpc_excp_booke(PowerPCCPU *cpu, int excp)
         break;
     case POWERPC_EXCP_MCHECK:    /* Machine check exception                  */
         if (!FIELD_EX64(env->msr, MSR, ME)) {
-            powerpc_checkstop(env);
+            powerpc_checkstop(env, "machine check with MSR[ME]=0");
         }
         /* machine check exceptions don't have ME set */
         new_msr &= ~((target_ulong)1 << MSR_ME);
@@ -1424,7 +1430,7 @@ static void powerpc_excp_books(PowerPCCPU *cpu, int excp)
     switch (excp) {
     case POWERPC_EXCP_MCHECK:    /* Machine check exception                  */
         if (!FIELD_EX64(env->msr, MSR, ME)) {
-            powerpc_checkstop(env);
+            powerpc_checkstop(env, "machine check with MSR[ME]=0");
         }
         if (env->msr_mask & MSR_HVB) {
             /*
-- 
2.40.1