From: Greg Kurz <gr...@kaod.org>
Commit 5d0fb1508e2d "spapr: consolidate the VCPU id numbering logic
in a single place" introduced a helper to detect thread0 of a virtual
core based on its VCPU id. This is used to create CPU core nodes in
the DT, but it is broken in TCG.
$ qemu-system-ppc64 -nographic -accel tcg -machine dumpdtb=dtb.bin \
-smp cores=16,maxcpus=16,threads=1
$ dtc -f -O dts dtb.bin | grep POWER8
PowerPC,POWER8@0 {
PowerPC,POWER8@8 {
instead of the expected 16 cores that we get with KVM:
$ dtc -f -O dts dtb.bin | grep POWER8
PowerPC,POWER8@0 {
PowerPC,POWER8@8 {
PowerPC,POWER8@10 {
PowerPC,POWER8@18 {
PowerPC,POWER8@20 {
PowerPC,POWER8@28 {
PowerPC,POWER8@30 {
PowerPC,POWER8@38 {
PowerPC,POWER8@40 {
PowerPC,POWER8@48 {
PowerPC,POWER8@50 {
PowerPC,POWER8@58 {
PowerPC,POWER8@60 {
PowerPC,POWER8@68 {
PowerPC,POWER8@70 {
PowerPC,POWER8@78 {
This happens because spapr_get_vcpu_id() maps VCPU ids to
cs->cpu_index in TCG mode. This confuses the code in
spapr_is_thread0_in_vcore(), since it assumes thread0 VCPU
ids to have a spapr->vsmt spacing.
spapr_get_vcpu_id(cpu) % spapr->vsmt == 0
Actually, there's no real reason to expose cs->cpu_index instead
of the VCPU id, since we also generate it with TCG. Also we already
set it explicitly in spapr_set_vcpu_id(), so there's no real reason
either to call kvm_arch_vcpu_id() with KVM.
This patch unifies spapr_get_vcpu_id() to always return the computed
VCPU id both in TCG and KVM. This is one step forward towards KVM<->TCG
migration.
Fixes: 5d0fb1508e2d
Reported-by: Cédric Le Goater <c...@kaod.org>
Signed-off-by: Greg Kurz <gr...@kaod.org>
Signed-off-by: David Gibson <da...@gibson.dropbear.id.au>
(cherry picked from commit b1a568c1c2192f090536b8ac76d135ce1f46a0ee)
Signed-off-by: Greg Kurz <gr...@kaod.org>
---
hw/ppc/spapr.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index a36494b87b..d53123c127 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -3655,13 +3655,7 @@ static void spapr_pic_print_info(InterruptStatsProvider
*obj,
int spapr_get_vcpu_id(PowerPCCPU *cpu)
{
- CPUState *cs = CPU(cpu);
-
- if (kvm_enabled()) {
- return kvm_arch_vcpu_id(cs);
- } else {
- return cs->cpu_index;
- }
+ return cpu->vcpu_id;
}
void spapr_set_vcpu_id(PowerPCCPU *cpu, int cpu_index, Error **errp)
--
2.11.0
