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| author | Josh Poimboeuf <jpoimboe@kernel.org> | 2023-09-04 22:04:46 -0700 |
|---|---|---|
| committer | Borislav Petkov (AMD) <bp@alien8.de> | 2023-09-19 10:54:07 +0200 |
| commit | 91857ae20303cc98ed36720d9868fcd604a2ee75 (patch) | |
| tree | 2fc861b55386ff6c056c2301a571d6e59b5af1a0 /mm/io-mapping.c | |
| parent | a8cf700c17d9ca6cb8ee7dc5c9330dbac3948237 (diff) | |
| download | linux-91857ae20303cc98ed36720d9868fcd604a2ee75.tar.gz linux-91857ae20303cc98ed36720d9868fcd604a2ee75.tar.bz2 linux-91857ae20303cc98ed36720d9868fcd604a2ee75.zip | |
x86/srso: Set CPUID feature bits independently of bug or mitigation status
Booting with mitigations=off incorrectly prevents the
X86_FEATURE_{IBPB_BRTYPE,SBPB} CPUID bits from getting set.
Also, future CPUs without X86_BUG_SRSO might still have IBPB with branch
type prediction flushing, in which case SBPB should be used instead of
IBPB. The current code doesn't allow for that.
Also, cpu_has_ibpb_brtype_microcode() has some surprising side effects
and the setting of these feature bits really doesn't belong in the
mitigation code anyway. Move it to earlier.
Fixes: fb3bd914b3ec ("x86/srso: Add a Speculative RAS Overflow mitigation")
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Nikolay Borisov <nik.borisov@suse.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/869a1709abfe13b673bdd10c2f4332ca253a40bc.1693889988.git.jpoimboe@kernel.org
Diffstat (limited to 'mm/io-mapping.c')
0 files changed, 0 insertions, 0 deletions