x86/bugs: Don't use cpu-type matching in cpu_vuln_blacklist

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Thomas Gleixner pointed out that cpu-type is a per-CPU property while hybrid
is a system property; conflating the two in the CPU matching infrastructure is
wrong. Currently, on a hybrid system x86_match_cpu() matches any cpu-type.
This works if the intent is to find the possibility of a cpu-type in a system.
But fails if matching for the cpu-type of a given CPU.

Borislav posted a cleanup here:

  https://lore.kernel.org/all/20260703193222.GFakgORjvxwnZTPRnI@fat_crate.local

To make way for the cleanup stop matching cpu-type in cpu_vuln_blacklist.
RFDS is the only user, so drop the VULNBL_INTEL_TYPE entries and fold their
RFDS bit into the base Alder Lake (0x97) and Raptor Lake (0xB7) blacklist
entries. For now open-code cpu-type check in vulnerable_to_rfds(). In the
future, if more vulnerabilities need cpu-type matching a helper can be added.

No functional change intended.

Fixes: 722fa0dba7 ("x86/rfds: Exclude P-only parts from the RFDS affected list")
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://patch.msgid.link/20260708-cpu-type-vuln-v1-1-85c1d3c704db@linux.intel.com

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This commit is contained in:

Pawan Gupta 2026-07-08 11:40:14 -07:00 • committed by Borislav Petkov (AMD)

parent 3eaa50e1e2

commit a4c714fe97

1 changed files with 17 additions and 8 deletions

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arch/x86/kernel/cpu/common.c

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