On 05/01/2023 15.53, Pierre Morel wrote:
The maximum nested topology entries is used by the guest to know
how many nested topology are available on the machine.
Currently, SCLP READ SCP INFO reports MNEST = 0, which is the
equivalent of reporting the default value of 2.
Let's use the default SCLP value of 2 and increase this value in the
future patches implementing higher levels.
I'm confused ... so does a SCLP value of 2 mean a MNEST level of 4 ?
Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
---
include/hw/s390x/sclp.h | 5 +++--
hw/s390x/sclp.c | 4 ++++
2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/include/hw/s390x/sclp.h b/include/hw/s390x/sclp.h
index 712fd68123..4ce852473c 100644
--- a/include/hw/s390x/sclp.h
+++ b/include/hw/s390x/sclp.h
@@ -112,12 +112,13 @@ typedef struct CPUEntry {
} QEMU_PACKED CPUEntry;
#define SCLP_READ_SCP_INFO_FIXED_CPU_OFFSET 128
-#define SCLP_READ_SCP_INFO_MNEST 2
+#define SCLP_READ_SCP_INFO_MNEST 4
... since you update it to 4 here.
typedef struct ReadInfo {
SCCBHeader h;
uint16_t rnmax;
uint8_t rnsize;
- uint8_t _reserved1[16 - 11]; /* 11-15 */
+ uint8_t _reserved1[15 - 11]; /* 11-14 */
+ uint8_t stsi_parm; /* 15-16 */
uint16_t entries_cpu; /* 16-17 */
uint16_t offset_cpu; /* 18-19 */
uint8_t _reserved2[24 - 20]; /* 20-23 */
diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c
index eff74479f4..07e3cb4cac 100644
--- a/hw/s390x/sclp.c
+++ b/hw/s390x/sclp.c
@@ -20,6 +20,7 @@
#include "hw/s390x/event-facility.h"
#include "hw/s390x/s390-pci-bus.h"
#include "hw/s390x/ipl.h"
+#include "hw/s390x/cpu-topology.h"
static inline SCLPDevice *get_sclp_device(void)
{
@@ -125,6 +126,9 @@ static void read_SCP_info(SCLPDevice *sclp, SCCB *sccb)
/* CPU information */
prepare_cpu_entries(machine, entries_start, &cpu_count);
+ if (s390_has_topology()) {
+ read_info->stsi_parm = SCLP_READ_SCP_INFO_MNEST;
This seems to be in contradiction to what you've said in the commit
description - you set it to 4 and not to 2.
Thomas
+ }
read_info->entries_cpu = cpu_to_be16(cpu_count);
read_info->offset_cpu = cpu_to_be16(offset_cpu);
read_info->highest_cpu = cpu_to_be16(machine->smp.max_cpus - 1);
