x86/fault: Skip the AMD erratum #91 workaround on unaffected CPUs
authorAndy Lutomirski <luto@kernel.org>
Wed, 10 Feb 2021 02:33:34 +0000 (18:33 -0800)
committerBorislav Petkov <bp@suse.de>
Wed, 10 Feb 2021 12:38:12 +0000 (13:38 +0100)
commitd24df8ecf9b6f81029f520ae7158a8670a28d70b
treed549abad0786bd19079ac1685770c65f7e0e4c7f
parent35f1c89b0cce247bf0213df243ed902989b1dcda
x86/fault: Skip the AMD erratum #91 workaround on unaffected CPUs

According to the Revision Guide for AMD Athlon™ 64 and AMD Opteron™
Processors, only early revisions of family 0xF are affected. This will
avoid unnecessarily fetching instruction bytes before sending SIGSEGV to
user programs.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/477173b7784bc28afb3e53d76ae5ef143917e8dd.1612924255.git.luto@kernel.org
arch/x86/mm/fault.c