diff options
| author | Marcos Del Sol Vives <marcos@orca.pet> | 2021-10-17 11:44:10 +0200 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2021-10-21 15:49:07 +0200 |
| commit | 639475d434b88b58827e1aae601ed1853803f5be (patch) | |
| tree | cc81c93c8ec0e1e151329de036ec4f2619cd03cf /arch/x86/Kconfig.cpu | |
| parent | f3f07ae425bc09039d9e0c73c86b76f95d9d5cd6 (diff) | |
x86/CPU: Add support for Vortex CPUs
DM&P devices were not being properly identified, which resulted in
unneeded Spectre/Meltdown mitigations being applied.
The manufacturer states that these devices execute always in-order and
don't support either speculative execution or branch prediction, so
they are not vulnerable to this class of attack. [1]
This is something I've personally tested by a simple timing analysis
on my Vortex86MX CPU, and can confirm it is true.
Add identification for some devices that lack the CPUID product name
call, so they appear properly on /proc/cpuinfo.
¹https://www.ssv-embedded.de/doks/infos/DMP_Ann_180108_Meltdown.pdf
[ bp: Massage commit message. ]
Signed-off-by: Marcos Del Sol Vives <marcos@orca.pet>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211017094408.1512158-1-marcos@orca.pet
Diffstat (limited to 'arch/x86/Kconfig.cpu')
| -rw-r--r-- | arch/x86/Kconfig.cpu | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu index 814fe0d349b0..eefc434351db 100644 --- a/arch/x86/Kconfig.cpu +++ b/arch/x86/Kconfig.cpu @@ -508,3 +508,16 @@ config CPU_SUP_ZHAOXIN CPU might render the kernel unbootable. If unsure, say N. + +config CPU_SUP_VORTEX_32 + default y + bool "Support Vortex processors" if PROCESSOR_SELECT + depends on X86_32 + help + This enables detection, tunings and quirks for Vortex processors + + You need this enabled if you want your kernel to run on a + Vortex CPU. Disabling this option on other types of CPUs + makes the kernel a tiny bit smaller. + + If unsure, say N. |