docs: add guidance on configuring CPU models for x86
PATCH v2 1/1 docs: add guidance on configuring CPU models for x86
With the recent set of CPU hardware vulnerabilities on x86, it is increasingly difficult to understand which CPU configurations are good to use and what flaws they might be vulnerable to.
This doc attempts to help management applications and administrators in picking sensible CPU configuration on x86 hosts. It outlines which of the named CPU models are good choices, and describes which extra CPU flags should be enabled to allow the guest to mitigate hardware flaws.
---
Changed in v2:
- Use texinfo so it can be pulled into main qemu-doc.texi
- Build as a standalone qemu-cpu-models(7) man page too
MAINTAINERS | 1 + Makefile | 7 +- docs/qemu-cpu-models.texi | 465 ++++++++++++++++++++++++++++++++++++++ qemu-doc.texi | 5 + 4 files changed, 477 insertions(+), 1 deletion(-) create mode 100644 docs/qemu-cpu-models.texi
MAINTAINERS +1 -0
@@ -285,6 +285,7 @@ S: Maintained F: target/i386/ F: hw/i386/ F: disas/i386.c +F: docs/qemu-cpu-models.texi T: git git://github.com/ehabkost/qemu.git x86-next Xtensa
Makefile +6 -1
@@ -359,6 +359,7 @@ DOCS=qemu-doc.html qemu-doc.txt qemu.1 qemu-img.1 qemu-nbd.8 qemu-ga.8 DOCS+=docs/interop/qemu-qmp-ref.html docs/interop/qemu-qmp-ref.txt docs/interop/qemu-qmp-ref.7 DOCS+=docs/interop/qemu-ga-ref.html docs/interop/qemu-ga-ref.txt docs/interop/qemu-ga-ref.7 DOCS+=docs/qemu-block-drivers.7 +DOCS+=docs/qemu-cpu-models.7 ifdef CONFIG_VIRTFS DOCS+=fsdev/virtfs-proxy-helper.1 endif
@@ -772,6 +773,7 @@ distclean: clean rm -f docs/interop/qemu-qmp-ref.pdf docs/interop/qemu-ga-ref.pdf rm -f docs/interop/qemu-qmp-ref.html docs/interop/qemu-ga-ref.html rm -f docs/qemu-block-drivers.7 + rm -f docs/qemu-cpu-models.7 for d in $(TARGET_LIST); do \ rm -rf $$d || exit 1 ; \ done
@@ -817,6 +819,7 @@ ifdef CONFIG_POSIX $(INSTALL_DIR) "$(DESTDIR)$(mandir)/man7" $(INSTALL_DATA) docs/interop/qemu-qmp-ref.7 "$(DESTDIR)$(mandir)/man7" $(INSTALL_DATA) docs/qemu-block-drivers.7 "$(DESTDIR)$(mandir)/man7" + $(INSTALL_DATA) docs/qemu-cpu-models.7 "$(DESTDIR)$(mandir)/man7" ifneq ($(TOOLS),) $(INSTALL_DATA) qemu-img.1 "$(DESTDIR)$(mandir)/man1" $(INSTALL_DIR) "$(DESTDIR)$(mandir)/man8"
@@ -959,6 +962,7 @@ fsdev/virtfs-proxy-helper.1: fsdev/virtfs-proxy-helper.texi qemu-nbd.8: qemu-nbd.texi qemu-option-trace.texi qemu-ga.8: qemu-ga.texi docs/qemu-block-drivers.7: docs/qemu-block-drivers.texi +docs/qemu-cpu-models.7: docs/qemu-cpu-models.texi html: qemu-doc.html docs/interop/qemu-qmp-ref.html docs/interop/qemu-ga-ref.html info: qemu-doc.info docs/interop/qemu-qmp-ref.info docs/interop/qemu-ga-ref.info
@@ -968,7 +972,8 @@ txt: qemu-doc.txt docs/interop/qemu-qmp-ref.txt docs/interop/qemu-ga-ref.txt qemu-doc.html qemu-doc.info qemu-doc.pdf qemu-doc.txt: \ qemu-img.texi qemu-nbd.texi qemu-options.texi qemu-option-trace.texi \ qemu-monitor.texi qemu-img-cmds.texi qemu-ga.texi \ - qemu-monitor-info.texi docs/qemu-block-drivers.texi + qemu-monitor-info.texi docs/qemu-block-drivers.texi \ + docs/qemu-cpu-models.texi docs/interop/qemu-ga-ref.dvi docs/interop/qemu-ga-ref.html \ docs/interop/qemu-ga-ref.info docs/interop/qemu-ga-ref.pdf \
docs/qemu-cpu-models.texi new file +465 -0
465 lines not on this page · raw message
qemu-doc.texi +5 -0
@@ -602,6 +602,11 @@ The monitor understands integers expressions for every integer argument. You can use register names to get the value of specifics CPU registers by prefixing them with @emph{$}. +@node cpu_models +@section CPU models + +@include docs/qemu-cpu-models.texi + @node disk_images @section Disk Images
Signature · 1 line
2.17.0
Quoted 10 lines · Daniel P. Berrangé
With the recent set of CPU hardware vulnerabilities on x86, it is increasingly difficult to understand which CPU configurations are good to use and what flaws they might be vulnerable to.
This doc attempts to help management applications and administrators in picking sensible CPU configuration on x86 hosts. It outlines which of the named CPU models are good choices, and describes which extra CPU flags should be enabled to allow the guest to mitigate hardware flaws.
Signed-off-by Daniel P. Berrangé <[email protected]>
This fails to build on a RHEL7 host:
# make qemu-doc.html V=1 LC_ALL=C makeinfo --no-split --number-sections -I docs -I . -I . --no-headers --html qemu-doc.texi -o qemu-doc.html qemu-doc.texi:127: node `QEMU PC System emulator' lacks menu item for `cpu_models' despite being its Up target qemu-doc.texi:605: node `cpu_models' lacks menu item for `recommendations_cpu_models_x86' despite being its Up target docs/qemu-cpu-models.texi:40: node `recommendations_cpu_models_x86' lacks menu item for `preferred_cpu_models_intel_x86' despite being its Up target docs/qemu-cpu-models.texi:40: node `recommendations_cpu_models_x86' lacks menu item for `important_cpu_features_intel_x86' despite being its Up target docs/qemu-cpu-models.texi:40: node `recommendations_cpu_models_x86' lacks menu item for `preferred_cpu_models_amd_x86' despite being its Up target docs/qemu-cpu-models.texi:40: node `recommendations_cpu_models_x86' lacks menu item for `important_cpu_features_amd_x86' despite being its Up target docs/qemu-cpu-models.texi:40: node `recommendations_cpu_models_x86' lacks menu item for `default_cpu_models_x86' despite being its Up target docs/qemu-cpu-models.texi:40: node `recommendations_cpu_models_x86' lacks menu item for `other_non_recommended_cpu_models_x86' despite being its Up target qemu-doc.texi:605: node `cpu_models' lacks menu item for `cpu_model_syntax_apps' despite being its Up target docs/qemu-cpu-models.texi:357: node `cpu_model_syntax_apps' lacks menu item for `cpu_model_syntax_qemu' despite being its Up target docs/qemu-cpu-models.texi:357: node `cpu_model_syntax_apps' lacks menu item for `cpu_model_syntax_libvirt' despite being its Up target make: *** [qemu-doc.html] Error 1 # rpm -qf /usr/bin/makeinfo texinfo-5.1-5.el7.x86_64
Signature · 1 line
Eduardo