spapr: fix missing CPU core nodes in DT when running with TCG
Commit 5d0fb150 "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: 5d0fb150Reported-by: NCédric Le Goater <clg@kaod.org> Signed-off-by: NGreg Kurz <groug@kaod.org> Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Showing
想要评论请 注册 或 登录