x86/speculation/mds: Add mds=full,nosmt cmdline option
commit d71eb0ce109a124b0fa714832823b9452f2762cf upstream.
Add the mds=full,nosmt cmdline option. This is like mds=full, but with
SMT disabled if the CPU is vulnerable.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
[bwh: Backported to 4.9: adjust filenames]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 7164790..4c13470 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2341,8 +2341,10 @@
This parameter controls the MDS mitigation. The
options are:
- full - Enable MDS mitigation on vulnerable CPUs
- off - Unconditionally disable MDS mitigation
+ full - Enable MDS mitigation on vulnerable CPUs
+ full,nosmt - Enable MDS mitigation and disable
+ SMT on vulnerable CPUs
+ off - Unconditionally disable MDS mitigation
Not specifying this option is equivalent to
mds=full.