diff options
| author | Josh Poimboeuf <[email protected]> | 2023-09-04 22:04:47 -0700 |
|---|---|---|
| committer | Borislav Petkov (AMD) <[email protected]> | 2023-09-19 10:54:23 +0200 |
| commit | 02428d0366a27c2f33bc4361eb10467777804f29 (patch) | |
| tree | 72563156e5fd534830a2967dc836c963e0257829 /tools/perf/scripts/python/export-to-sqlite.py | |
| parent | 91857ae20303cc98ed36720d9868fcd604a2ee75 (diff) | |
x86/srso: Don't probe microcode in a guest
To support live migration, the hypervisor sets the "lowest common
denominator" of features. Probing the microcode isn't allowed because
any detected features might go away after a migration.
As Andy Cooper states:
"Linux must not probe microcode when virtualised. What it may see
instantaneously on boot (owing to MSR_PRED_CMD being fully passed
through) is not accurate for the lifetime of the VM."
Rely on the hypervisor to set the needed IBPB_BRTYPE and SBPB bits.
Fixes: 1b5277c0ea0b ("x86/srso: Add SRSO_NO support")
Suggested-by: Andrew Cooper <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Borislav Petkov (AMD) <[email protected]>
Reviewed-by: Andrew Cooper <[email protected]>
Acked-by: Borislav Petkov (AMD) <[email protected]>
Link: https://lore.kernel.org/r/3938a7209606c045a3f50305d201d840e8c834c7.1693889988.git.jpoimboe@kernel.org
Diffstat (limited to 'tools/perf/scripts/python/export-to-sqlite.py')
0 files changed, 0 insertions, 0 deletions