On Mon, 11 Sep 2017 17:21:40 +0200
David Hildenbrand <da...@redhat.com> wrote:
> Specifying more than 1 CPU (e.g. -smp 5) leads to SIGP errors (the
> guest tries to bring these CPUs up but fails), because we don't support
> multiple CPUs on s390x under TCG.
>
> Let's bail out if more than 1 is specified, so we don't raise people's
> hope. Make it a define, so we can easily bump it up later.
>
> Tested-by: Matthew Rosato <mjros...@linux.vnet.ibm.com>
> Signed-off-by: David Hildenbrand <da...@redhat.com>
> ---
> hw/s390x/s390-virtio-ccw.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
> index f67b4b5d58..f1198b2745 100644
> --- a/hw/s390x/s390-virtio-ccw.c
> +++ b/hw/s390x/s390-virtio-ccw.c
> @@ -23,6 +23,7 @@
> #include "hw/s390x/css.h"
> #include "virtio-ccw.h"
> #include "qemu/config-file.h"
> +#include "qemu/error-report.h"
> #include "s390-pci-bus.h"
> #include "hw/s390x/storage-keys.h"
> #include "hw/s390x/storage-attributes.h"
> @@ -47,6 +48,8 @@ S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
> return cpu_states[cpu_addr];
> }
>
> +/* #define S390_TCG_SMP_SUPPORT */
I'd drop define and ifdef for something that doesn't exists
> static void s390_init_cpus(MachineState *machine)
> {
> int i;
> @@ -55,6 +58,13 @@ static void s390_init_cpus(MachineState *machine)
> if (machine->cpu_model == NULL) {
> machine->cpu_model = s390_default_cpu_model_name();
> }
> +#ifndef S390_TCG_SMP_SUPPORT
> + if (tcg_enabled() && max_cpus > 1) {
> + error_report("Number of SMP CPUs requested (%d) exceeds max CPUs "
> + "supported by TCG (1) on s390x", max_cpus);
> + exit(1);
> + }
> +#endif
>
> cpu_states = g_new0(S390CPU *, max_cpus);
>
