checkstop state does not halt the system, interrupts continue to be
serviced, and other CPUs run. Make it stop the machine with
qemu_system_guest_panicked.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 target/ppc/excp_helper.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
index 3be086d10b..b2b51537b7 100644
--- a/target/ppc/excp_helper.c
+++ b/target/ppc/excp_helper.c
@@ -19,6 +19,8 @@
 #include "qemu/osdep.h"
 #include "qemu/main-loop.h"
 #include "qemu/log.h"
+#include "sysemu/sysemu.h"
+#include "sysemu/runstate.h"
 #include "cpu.h"
 #include "exec/exec-all.h"
 #include "internal.h"
@@ -425,6 +427,8 @@ static void powerpc_set_excp_state(PowerPCCPU *cpu, target_ulong vector,
 
 static void powerpc_mcheck_checkstop(CPUPPCState *env)
 {
+    /* KVM guests always have MSR[ME] enabled */
+#ifdef CONFIG_TCG
     CPUState *cs = env_cpu(env);
 
     if (FIELD_EX64(env->msr, MSR, ME)) {
@@ -437,9 +441,15 @@ static void powerpc_mcheck_checkstop(CPUPPCState *env)
     if (qemu_log_separate()) {
         qemu_log("Machine check while not allowed. "
                  "Entering checkstop state\n");
-    }
-    cs->halted = 1;
-    cpu_interrupt_exittb(cs);
+
+    /*
+     * This stops the machine and logs CPU state without killing QEMU
+     * (like cpu_abort()) so the machine can still be debugged (because
+     * it is often a guest error).
+     */
+    qemu_system_guest_panicked(NULL);
+    cpu_loop_exit_noexc(cs);
+#endif
 }
 
 static void powerpc_excp_40x(PowerPCCPU *cpu, int excp)
-- 
2.43.0

Reviewed-by: Glenn Miles <milesg@linux.ibm.com>

Thanks,

Glenn

On Tue, 2024-05-21 at 11:30 +1000, Nicholas Piggin wrote:
> checkstop state does not halt the system, interrupts continue to be
> serviced, and other CPUs run. Make it stop the machine with
> qemu_system_guest_panicked.
> 
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>  target/ppc/excp_helper.c | 16 +++++++++++++---
>  1 file changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
> index 3be086d10b..b2b51537b7 100644
> --- a/target/ppc/excp_helper.c
> +++ b/target/ppc/excp_helper.c
> @@ -19,6 +19,8 @@
>  #include "qemu/osdep.h"
>  #include "qemu/main-loop.h"
>  #include "qemu/log.h"
> +#include "sysemu/sysemu.h"
> +#include "sysemu/runstate.h"
>  #include "cpu.h"
>  #include "exec/exec-all.h"
>  #include "internal.h"
> @@ -425,6 +427,8 @@ static void powerpc_set_excp_state(PowerPCCPU
> *cpu, target_ulong vector,
>  
>  static void powerpc_mcheck_checkstop(CPUPPCState *env)
>  {
> +    /* KVM guests always have MSR[ME] enabled */
> +#ifdef CONFIG_TCG
>      CPUState *cs = env_cpu(env);
>  
>      if (FIELD_EX64(env->msr, MSR, ME)) {
> @@ -437,9 +441,15 @@ static void powerpc_mcheck_checkstop(CPUPPCState
> *env)
>      if (qemu_log_separate()) {
>          qemu_log("Machine check while not allowed. "
>                   "Entering checkstop state\n");
> -    }
> -    cs->halted = 1;
> -    cpu_interrupt_exittb(cs);
> +
> +    /*
> +     * This stops the machine and logs CPU state without killing
> QEMU
> +     * (like cpu_abort()) so the machine can still be debugged
> (because
> +     * it is often a guest error).
> +     */
> +    qemu_system_guest_panicked(NULL);
> +    cpu_loop_exit_noexc(cs);
> +#endif
>  }
>  
>  static void powerpc_excp_40x(PowerPCCPU *cpu, int excp)