On Mon, 3 Jul 2023, Nicholas Piggin wrote:
checkstop state does not halt the system, interrupts continue to be
serviced, and other CPUs run. Stop the machine with
qemu_system_guest_panicked.
Change the logging not to print separately to stderr because a
checkstop is a guest error (or perhaps a simulated machine error)
rather than a QEMU error. CPU registers are dumped.
Signed-off-by: Nicholas Piggin <npig...@gmail.com>
Since v1:
- Fix loop exit so it stops on the checkstop-causing instruction, rather than
after it.
Since v2:
- Rebase on ppc-next.
Is this really based on ppc-next or on my series or another patch from
you? I think the patch from my series that introduces the checksrop
function that this patch is changing is not yet in ppc-next so this may
not apply there. I think you've posted an alternative to the patch moving
checkstop handling to a function and the sc patch which may clash with the
not yet merged parts in my series but i could not follow all these
patches. I'm not sure Daniel could so maybe you could send it as a series
to include all patches you want to add or state what it's based on.
Regards,
BALATON Zoltan
- Use qemu_system_guest_panicked rather than vm_stop (Richard)
- Move away from printing to stderr (Zoltan)
- Reduce changes to log messages.
- Split out from larger series since it's independent (will skip attn
instruction for now).
---
target/ppc/excp_helper.c | 26 ++++++++++++++++++--------
1 file changed, 18 insertions(+), 8 deletions(-)
diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
index e49e13a30d..a588285ef1 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"
@@ -427,20 +428,29 @@ static void powerpc_set_excp_state(PowerPCCPU *cpu,
target_ulong vector,
static void powerpc_mcheck_checkstop(CPUPPCState *env)
{
CPUState *cs = env_cpu(env);
+ FILE *f;
if (FIELD_EX64(env->msr, MSR, ME)) {
return;
}
- /* Machine check exception is not enabled. Enter checkstop state. */
- fprintf(stderr, "Machine check while not allowed. "
- "Entering checkstop state\n");
- if (qemu_log_separate()) {
- qemu_log("Machine check while not allowed. "
- "Entering checkstop state\n");
+ /*
+ * 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).
+ */
+
+ f = qemu_log_trylock();
+ if (f) {
+ fprintf(f, "Machine check while not allowed. "
+ "Entering checkstop state.\n");
+ cpu_dump_state(cs, f, CPU_DUMP_FPU | CPU_DUMP_CCOP);
+ qemu_log_unlock(f);
}
- cs->halted = 1;
- cpu_interrupt_exittb(cs);
+
+ qemu_system_guest_panicked(NULL);
+
+ cpu_loop_exit_noexc(cs);
}
static void powerpc_excp_40x(PowerPCCPU *cpu, int excp)