x86/bugs: Add attack vector controls for MDS
authorDavid Kaplan <david.kaplan@amd.com>
Mon, 7 Jul 2025 18:33:00 +0000 (13:33 -0500)
committerBorislav Petkov (AMD) <bp@alien8.de>
Fri, 11 Jul 2025 15:56:40 +0000 (17:56 +0200)
commite3a88d4c068242c00a1d6ddfd3c711fc22983f75
tree06c0c8264d2fa57073f2100662207ffb834933b3
parent2d31d2874663cde2cab8c18bfb52ed8be6dfa958
x86/bugs: Add attack vector controls for MDS

Use attack vector controls to determine if MDS mitigation is required.
The global mitigations=off command now simply disables all attack vectors
so explicit checking of mitigations=off is no longer needed.

If cross-thread attack mitigations are required, disable SMT.

Signed-off-by: David Kaplan <david.kaplan@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/20250707183316.1349127-6-david.kaplan@amd.com
arch/x86/kernel/cpu/bugs.c