tmakin/ack-tegra
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

x86/its: Add "vmexit" option to skip mitigation on some CPUs

Browse Source 
commit 2665281a07e19550944e8354a2024635a7b2714a upstream.

Ice Lake generation CPUs are not affected by guest/host isolation part of
ITS. If a user is only concerned about KVM guests, they can now choose a
new cmdline option "vmexit" that will not deploy the ITS mitigation when
CPU is not affected by guest/host isolation. This saves the performance
overhead of ITS mitigation on Ice Lake gen CPUs.

When "vmexit" option selected, if the CPU is affected by ITS guest/host
isolation, the default ITS mitigation is deployed.

Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Pawan Gupta
2024-11-18 09:53:12 -08:00
committed by Greg Kroah-Hartman
parent 68d59e9ba3
commit 4dc1902fde
4 changed files with 26 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files
Documentation/admin-guide/kernel-parameters.txt
+2
View File
@@ -2157,6 +2157,8 @@
off: Disable mitigation.
force: Force the ITS bug and deploy default
mitigation.
vmexit: Only deploy mitigation if CPU is affected by
guest/host isolation part of ITS.
For details see:
Documentation/admin-guide/hw-vuln/indirect-target-selection.rst