[libvirt] [PATCH 13/14] cpu: Avoid adding <vendor> to custom CPUs

Guest CPU definitions with mode='custom' and missing <vendor> are expected to run on a host CPU from any vendor as long as the required CPU model can be used as a guest CPU on the host. But even though no CPU vendor was explicitly requested we would sometimes force it due to a bug in virCPUUpdate and virCPUTranslate. The bug would effectively forbid cross vendor migrations even if they were previously working just fine. Signed-off-by: Jiri Denemark <jdenemar(a)redhat.com&gt; --- src/conf/cpu_conf.c | 28 +++++++++++++++++++--- src/conf/cpu_conf.h | 3 ++- src/cpu/cpu_arm.c | 2 +- src/cpu/cpu_x86.c | 5 ++-- .../cputestdata/x86-host+guest,model486-result.xml | 1 - tests/cputestdata/x86-host+guest,models-result.xml | 1 - tests/cputestdata/x86-host+min.xml | 1 - tests/cputestdata/x86-host+pentium3.xml | 1 - ...-Haswell-noTSX+Haswell-noTSX,haswell-result.xml | 1 - .../x86-host-better+pentium3-result.xml | 1 - 10 files changed, 31 insertions(+), 13 deletions(-) diff --git a/src/conf/cpu_conf.c b/src/conf/cpu_conf.c index f174529..9eb69c9 100644 --- a/src/conf/cpu_conf.c +++ b/src/conf/cpu_conf.c @@ -132,20 +132,42 @@ virCPUDefCopyModelFilter(virCPUDefPtr dst, } +/** + * virCPUDefStealModel: + * + * Move CPU model related parts virCPUDef from @src to @dst. If @keepVendor + * is true, the function keeps the original vendor/vendor_id in @dst rather + * than overwriting it with the values from @src. + */ void virCPUDefStealModel(virCPUDefPtr dst, - virCPUDefPtr src) + virCPUDefPtr src, + bool keepVendor) { + char *vendor; + char *vendor_id; + + if (keepVendor) { + VIR_STEAL_PTR(vendor, dst->vendor); + VIR_STEAL_PTR(vendor_id, dst->vendor_id); + } + virCPUDefFreeModel(dst); VIR_STEAL_PTR(dst->model, src->model); - VIR_STEAL_PTR(dst->vendor, src->vendor); - VIR_STEAL_PTR(dst->vendor_id, src->vendor_id); VIR_STEAL_PTR(dst->features, src->features); dst->nfeatures_max = src->nfeatures_max; src->nfeatures_max = 0; dst->nfeatures = src->nfeatures; src->nfeatures = 0; + + if (keepVendor) { + dst->vendor = vendor; + dst->vendor_id = vendor_id; + } else { + VIR_STEAL_PTR(dst->vendor, src->vendor); + VIR_STEAL_PTR(dst->vendor_id, src->vendor_id); + } } diff --git a/src/conf/cpu_conf.h b/src/conf/cpu_conf.h index e084392..cc3fbf0 100644 --- a/src/conf/cpu_conf.h +++ b/src/conf/cpu_conf.h @@ -139,7 +139,8 @@ virCPUDefCopyModelFilter(virCPUDefPtr dst, void virCPUDefStealModel(virCPUDefPtr dst, - virCPUDefPtr src); + virCPUDefPtr src, + bool keepVendor); virCPUDefPtr virCPUDefCopy(const virCPUDef *cpu); diff --git a/src/cpu/cpu_arm.c b/src/cpu/cpu_arm.c index db603a6..b5002c3 100644 --- a/src/cpu/cpu_arm.c +++ b/src/cpu/cpu_arm.c @@ -67,7 +67,7 @@ virCPUarmUpdate(virCPUDefPtr guest, if (virCPUDefCopyModel(updated, host, true) < 0) goto cleanup; - virCPUDefStealModel(guest, updated); + virCPUDefStealModel(guest, updated, false); guest->mode = VIR_CPU_MODE_CUSTOM; guest->match = VIR_CPU_MATCH_EXACT; ret = 0; diff --git a/src/cpu/cpu_x86.c b/src/cpu/cpu_x86.c index 4f2a111..851ec5d 100644 --- a/src/cpu/cpu_x86.c +++ b/src/cpu/cpu_x86.c @@ -2576,7 +2576,8 @@ x86UpdateHostModel(virCPUDefPtr guest, goto cleanup; } - virCPUDefStealModel(guest, updated); + virCPUDefStealModel(guest, updated, + guest->mode == VIR_CPU_MODE_CUSTOM); guest->mode = VIR_CPU_MODE_CUSTOM; guest->match = VIR_CPU_MATCH_EXACT; ret = 0; @@ -2737,7 +2738,7 @@ virCPUx86Translate(virCPUDefPtr cpu, goto cleanup; } - virCPUDefStealModel(cpu, translated); + virCPUDefStealModel(cpu, translated, true); ret = 0; cleanup: diff --git a/tests/cputestdata/x86-host+guest,model486-result.xml b/tests/cputestdata/x86-host+guest,model486-result.xml index 88df467..85564ff 100644 --- a/tests/cputestdata/x86-host+guest,model486-result.xml +++ b/tests/cputestdata/x86-host+guest,model486-result.xml @@ -1,6 +1,5 @@ <cpu mode='custom' match='exact'> <model fallback='allow'>486</model> - <vendor>Intel</vendor> <topology sockets='2' cores='4' threads='1'/> <feature policy='require' name='de'/> <feature policy='require' name='tsc'/> diff --git a/tests/cputestdata/x86-host+guest,models-result.xml b/tests/cputestdata/x86-host+guest,models-result.xml index e7a77c2..f79ed32 100644 --- a/tests/cputestdata/x86-host+guest,models-result.xml +++ b/tests/cputestdata/x86-host+guest,models-result.xml @@ -1,6 +1,5 @@ <cpu mode='custom' match='exact'> <model fallback='allow'>Nehalem</model> - <vendor>Intel</vendor> <topology sockets='2' cores='4' threads='1'/> <feature policy='force' name='pbe'/> <feature policy='force' name='monitor'/> diff --git a/tests/cputestdata/x86-host+min.xml b/tests/cputestdata/x86-host+min.xml index a284767..8101151 100644 --- a/tests/cputestdata/x86-host+min.xml +++ b/tests/cputestdata/x86-host+min.xml @@ -1,6 +1,5 @@ <cpu mode='custom' match='exact'> <model fallback='allow'>Penryn</model> - <vendor>Intel</vendor> <feature policy='require' name='dca'/> <feature policy='require' name='xtpr'/> <feature policy='require' name='tm2'/> diff --git a/tests/cputestdata/x86-host+pentium3.xml b/tests/cputestdata/x86-host+pentium3.xml index a284767..8101151 100644 --- a/tests/cputestdata/x86-host+pentium3.xml +++ b/tests/cputestdata/x86-host+pentium3.xml @@ -1,6 +1,5 @@ <cpu mode='custom' match='exact'> <model fallback='allow'>Penryn</model> - <vendor>Intel</vendor> <feature policy='require' name='dca'/> <feature policy='require' name='xtpr'/> <feature policy='require' name='tm2'/> diff --git a/tests/cputestdata/x86-host-Haswell-noTSX+Haswell-noTSX,haswell-result.xml b/tests/cputestdata/x86-host-Haswell-noTSX+Haswell-noTSX,haswell-result.xml index 5902f6c..5d149bb 100644 --- a/tests/cputestdata/x86-host-Haswell-noTSX+Haswell-noTSX,haswell-result.xml +++ b/tests/cputestdata/x86-host-Haswell-noTSX+Haswell-noTSX,haswell-result.xml @@ -1,6 +1,5 @@ <cpu mode='custom' match='exact'> <model fallback='allow'>Haswell</model> - <vendor>Intel</vendor> <topology sockets='1' cores='2' threads='2'/> <feature policy='disable' name='hle'/> <feature policy='disable' name='rtm'/> diff --git a/tests/cputestdata/x86-host-better+pentium3-result.xml b/tests/cputestdata/x86-host-better+pentium3-result.xml index 12336da..9d4f98f 100644 --- a/tests/cputestdata/x86-host-better+pentium3-result.xml +++ b/tests/cputestdata/x86-host-better+pentium3-result.xml @@ -1,6 +1,5 @@ <cpu mode='custom' match='exact'> <model fallback='allow'>Nehalem</model> - <vendor>Intel</vendor> <feature policy='require' name='dca'/> <feature policy='require' name='xtpr'/> <feature policy='require' name='tm2'/> -- 2.10.2