From 3b9e2f17d091c57f1fe7cbad18b0985e0644d8c2 Mon Sep 17 00:00:00 2001
Message-Id: <3b9e2f17d091c57f1fe7cbad18b0985e0644d8c2@dist-git>
From: Jiri Denemark <jdenemar@redhat.com>
Date: Fri, 22 Nov 2019 11:19:24 +0100
Subject: [PATCH] cpu_map: Drop pconfig from Icelake-Server CPU model
MIME-Version: 1.0
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The pconfig feature was enabled in QEMU by accident in 3.1.0. All other
newer versions do not support it and it was removed from the
Icelake-Server CPU model in QEMU.
We don't normally change our CPU models even when QEMU does so to avoid
breaking migrations between different versions of libvirt. But we can
safely do so in this specific case. QEMU never supported enabling
pconfig so any domain which was able to start has pconfig disabled.
With a small compatibility hack which explicitly disables pconfig when
CPU model equals Icelake-Server in migratable domain definition, only
one migration scenario stays broken (and there's nothing we can do about
it): from any host to a host with libvirt < 5.10.0 and QEMU > 3.1.0.
https://bugzilla.redhat.com/show_bug.cgi?id=1749672
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
(cherry picked from commit 9cd03f7957e114892ae54e7ccb3758b6fb440644)
https://bugzilla.redhat.com/show_bug.cgi?id=1775133
https://bugzilla.redhat.com/show_bug.cgi?id=1775134
https://bugzilla.redhat.com/show_bug.cgi?id=1775137
Conflicts:
src/cpu_map/x86_Icelake-Server.xml
- still monolithic cpu_map.xml downstream
src/qemu/qemu_domain.h
- context
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Message-Id: <430d543cce32100e879f1a5ea125abd4428aecf0.1574417839.git.jdenemar@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
---
src/cpu/cpu_map.xml | 1 -
src/qemu/qemu_domain.c | 23 +++++++++++++++++++
src/qemu/qemu_domain.h | 3 +++
src/qemu/qemu_migration_cookie.c | 3 +++
.../x86_64-cpuid-Ice-Lake-Server-guest.xml | 1 -
.../x86_64-cpuid-Ice-Lake-Server-host.xml | 11 +--------
.../x86_64-cpuid-Ice-Lake-Server-json.xml | 1 -
7 files changed, 30 insertions(+), 13 deletions(-)
diff --git a/src/cpu/cpu_map.xml b/src/cpu/cpu_map.xml
index acd9dad7dc..7b9f8bb452 100644
--- a/src/cpu/cpu_map.xml
+++ b/src/cpu/cpu_map.xml
@@ -2176,7 +2176,6 @@
<feature name='pat'/>
<feature name='pcid'/>
<feature name='pclmuldq'/>
- <feature name='pconfig'/>
<feature name='pdpe1gb'/>
<feature name='pge'/>
<feature name='pku'/>
diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index c9899b9e6d..f45d7d427e 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -7348,6 +7348,26 @@ qemuDomainDefCopy(virQEMUDriverPtr driver,
}
+int
+qemuDomainMakeCPUMigratable(virCPUDefPtr cpu)
+{
+ if (cpu->mode == VIR_CPU_MODE_CUSTOM &&
+ STREQ_NULLABLE(cpu->model, "Icelake-Server")) {
+ /* Originally Icelake-Server CPU model contained pconfig CPU feature.
+ * It was never actually enabled and thus it was removed. To enable
+ * migration to QEMU 3.1.0 (with both new and old libvirt), we
+ * explicitly disable pconfig in migration XML (otherwise old libvirt
+ * would think it was implicitly enabled on the source). New libvirt
+ * will drop it from the XML before starting the domain on new QEMU.
+ */
+ if (virCPUDefUpdateFeature(cpu, "pconfig", VIR_CPU_FEATURE_DISABLE) < 0)
+ return -1;
+ }
+
+ return 0;
+}
+
+
static int
qemuDomainDefFormatBufInternal(virQEMUDriverPtr driver,
virDomainDefPtr def,
@@ -7522,6 +7542,9 @@ qemuDomainDefFormatBufInternal(virQEMUDriverPtr driver,
if (!(def->cpu = virCPUDefCopy(origCPU)))
goto cleanup;
}
+
+ if (qemuDomainMakeCPUMigratable(def->cpu) < 0)
+ goto cleanup;
}
format:
diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h
index 8463a8b706..a29a678771 100644
--- a/src/qemu/qemu_domain.h
+++ b/src/qemu/qemu_domain.h
@@ -1072,4 +1072,7 @@ char * qemuDomainGetManagedPRSocketPath(qemuDomainObjPrivatePtr priv);
virDomainEventResumedDetailType
qemuDomainRunningReasonToResumeEvent(virDomainRunningReason reason);
+int
+qemuDomainMakeCPUMigratable(virCPUDefPtr cpu);
+
#endif /* __QEMU_DOMAIN_H__ */
diff --git a/src/qemu/qemu_migration_cookie.c b/src/qemu/qemu_migration_cookie.c
index 60df449d53..c270896944 100644
--- a/src/qemu/qemu_migration_cookie.c
+++ b/src/qemu/qemu_migration_cookie.c
@@ -543,6 +543,9 @@ qemuMigrationCookieAddCPU(qemuMigrationCookiePtr mig,
if (!(mig->cpu = virCPUDefCopy(vm->def->cpu)))
return -1;
+ if (qemuDomainMakeCPUMigratable(mig->cpu) < 0)
+ return -1;
+
mig->flags |= QEMU_MIGRATION_COOKIE_CPU;
return 0;
diff --git a/tests/cputestdata/x86_64-cpuid-Ice-Lake-Server-guest.xml b/tests/cputestdata/x86_64-cpuid-Ice-Lake-Server-guest.xml
index 6ca2099b33..4676f3aa7d 100644
--- a/tests/cputestdata/x86_64-cpuid-Ice-Lake-Server-guest.xml
+++ b/tests/cputestdata/x86_64-cpuid-Ice-Lake-Server-guest.xml
@@ -32,5 +32,4 @@
<feature policy='require' name='rdctl-no'/>
<feature policy='require' name='ibrs-all'/>
<feature policy='require' name='skip-l1dfl-vmentry'/>
- <feature policy='disable' name='pconfig'/>
</cpu>
diff --git a/tests/cputestdata/x86_64-cpuid-Ice-Lake-Server-host.xml b/tests/cputestdata/x86_64-cpuid-Ice-Lake-Server-host.xml
index 31af20bc85..35b9e39629 100644
--- a/tests/cputestdata/x86_64-cpuid-Ice-Lake-Server-host.xml
+++ b/tests/cputestdata/x86_64-cpuid-Ice-Lake-Server-host.xml
@@ -1,6 +1,6 @@
<cpu>
<arch>x86_64</arch>
- <model>Icelake-Client</model>
+ <model>Icelake-Server</model>
<vendor>Intel</vendor>
<feature name='ds'/>
<feature name='acpi'/>
@@ -21,23 +21,14 @@
<feature name='osxsave'/>
<feature name='tsc_adjust'/>
<feature name='cmt'/>
- <feature name='avx512f'/>
- <feature name='avx512dq'/>
<feature name='avx512ifma'/>
- <feature name='clflushopt'/>
- <feature name='clwb'/>
- <feature name='avx512cd'/>
<feature name='sha-ni'/>
- <feature name='avx512bw'/>
- <feature name='avx512vl'/>
<feature name='ospke'/>
- <feature name='la57'/>
<feature name='stibp'/>
<feature name='arch-capabilities'/>
<feature name='xsaves'/>
<feature name='mbm_total'/>
<feature name='mbm_local'/>
- <feature name='pdpe1gb'/>
<feature name='invtsc'/>
<feature name='rdctl-no'/>
<feature name='ibrs-all'/>
diff --git a/tests/cputestdata/x86_64-cpuid-Ice-Lake-Server-json.xml b/tests/cputestdata/x86_64-cpuid-Ice-Lake-Server-json.xml
index b043db58d7..ada11d2608 100644
--- a/tests/cputestdata/x86_64-cpuid-Ice-Lake-Server-json.xml
+++ b/tests/cputestdata/x86_64-cpuid-Ice-Lake-Server-json.xml
@@ -13,5 +13,4 @@
<feature policy='require' name='ibrs-all'/>
<feature policy='require' name='skip-l1dfl-vmentry'/>
<feature policy='disable' name='intel-pt'/>
- <feature policy='disable' name='pconfig'/>
</cpu>
--
2.24.0