qemu/docs
Pierrick Bouvier 132f8ec799 target/arm: change default pauth algorithm to impdef
Pointer authentication on aarch64 is pretty expensive (up to 50% of
execution time) when running a virtual machine with tcg and -cpu max
(which enables pauth=on).

The advice is always: use pauth-impdef=on.
Our documentation even mentions it "by default" in
docs/system/introduction.rst.

Thus, we change the default to use impdef by default. This does not
affect kvm or hvf acceleration, since pauth algorithm used is the one
from host cpu.

This change is retro compatible, in terms of cli, with previous
versions, as the semantic of using -cpu max,pauth-impdef=on, and -cpu
max,pauth-qarma3=on is preserved.
The new option introduced in previous patch and matching old default is
-cpu max,pauth-qarma5=on.
It is retro compatible with migration as well, by defining a backcompat
property, that will use qarma5 by default for virt machine <= 9.2.
Tested by saving and restoring a vm from qemu 9.2.0 into qemu-master
(10.0) for cpus neoverse-n2 and max.

Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241219183211.3493974-3-pierrick.bouvier@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2025-01-13 12:35:34 +00:00
..
_templates docs: Add QEMU version information to HTML footer 2021-07-18 10:59:47 +01:00
about docs/about/deprecated: Remove paragraph about initial deprecation in 2.10 2025-01-07 15:01:52 +01:00
config vl: recognize audiodev groups in configuration files 2023-09-22 17:35:11 +02:00
devel docs/devel: remove dead video link for sourcehut submit process 2024-12-28 14:42:52 +03:00
interop docs: fix vhost-user protocol doc 2024-11-04 16:01:54 -05:00
specs Accel & Exec patch queue 2024-12-21 11:07:00 -05:00
sphinx docs/sphinx: fix extra stuff in TOC after freeform QMP sections 2024-08-27 11:10:58 +02:00
sphinx-static docs/sphinx: add CSS styling for qmp-example directive 2024-07-17 10:20:53 +02:00
spin docs: create config/, devel/ and spin/ subdirectories 2017-06-07 18:22:03 +02:00
system target/arm: change default pauth algorithm to impdef 2025-01-13 12:35:34 +00:00
tools 9p: remove 'proxy' filesystem backend driver 2024-10-03 19:33:25 +02:00
user linux-user: Remove support for CRIS target 2024-09-13 20:10:50 +02:00
block-replication.txt docs/block-replication.txt: Fix replication top-id command demo 2021-12-17 11:35:00 +01:00
bypass-iommu.txt docs: Add documentation for iommu bypass 2021-07-16 11:10:45 -04:00
COLO-FT.txt chardev: finalize 'reconnect' deprecation 2024-10-28 14:37:25 +08:00
colo-proxy.txt colo: examples: remove mentions of script= and (wrong) downscript= 2024-01-30 21:20:20 +03:00
conf.py docs: update copyright date to the year 2025 2025-01-02 07:44:28 +01:00
defs.rst.inc docs: Fix typo in the default name of the qemu-system-x86_64 binary 2021-04-01 14:28:39 +02:00
igd-assign.txt vfio/pci: Add IGD documentation 2016-05-26 11:12:05 -06:00
image-fuzzer.txt docs: Render binary names as monospaced text 2021-11-22 15:02:38 +01:00
index.rst docs: standardize book titles to === with overline 2021-09-13 13:56:26 +02:00
memory-hotplug.txt docs: Grammar and spelling fixes 2018-07-13 10:16:04 +01:00
meson.build 9p: remove 'proxy' filesystem backend driver 2024-10-03 19:33:25 +02:00
multi-thread-compression.txt docs tests: Fix use of migrate_set_parameter 2023-09-08 13:08:52 +03:00
multiseat.txt docs: Spell QEMU all caps 2021-11-19 10:16:58 +01:00
nvdimm.txt docs/nvdimm: Update nvdimm option value in machine example 2021-09-27 10:57:21 +02:00
pci_expander_bridge.txt docs, tests: do not specify scsi=off 2024-06-05 11:00:56 +02:00
pcie.txt docs/pcie.txt: Replace ioh3420 with pcie-root-port 2023-01-28 06:21:30 -05:00
pcie_pci_bridge.txt docs: add slot when adding new PCIe root port 2021-07-03 03:12:35 -04:00
pcie_sriov.txt Revert "pcie_sriov: Ensure VF function number does not overflow" 2024-08-01 04:32:00 -04:00
qcow2-cache.txt qcow2: Document the Extended L2 Entries feature 2020-08-25 08:33:20 +02:00
qdev-device-use.txt util: remove support -chardev tty and -chardev parport 2023-01-06 00:51:02 +01:00
qemu-option-trace.rst.inc qemu-option-trace.rst.inc: Don't use option:: markup 2020-11-02 16:52:18 +00:00
qemupciserial.inf docs: Grammar and spelling fixes 2018-07-13 10:16:04 +01:00
rdma.txt docs tests: Fix use of migrate_set_parameter 2023-09-08 13:08:52 +03:00
requirements.txt pythondeps.toml: warn about updates needed to docs/requirements.txt 2024-04-23 17:35:26 +02:00
spice-port-fqdn.txt docs: add spice-port-fqdn.txt 2012-12-17 14:01:41 +01:00
throttle.txt docs: Drop deprecated 'props' from object-add 2021-11-22 15:02:38 +01:00
xbzrle.txt migrate: remove QMP/HMP commands for speed, downtime and cache size 2021-03-18 09:22:55 +00:00
xen-save-devices-state.txt Fix up dangling references to qmp-commands.* in comment and doc 2018-03-02 13:48:26 -06:00