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| author | Pawan Gupta <pawan.kumar.gupta@linux.intel.com> | 2025-08-14 10:20:42 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-09-11 17:17:17 +0200 |
| commit | 2f4f2f8f860cb4c3336a7435ebe8dcfded0c9c6e (patch) | |
| tree | d6c435f2b3368c5f1dd459006ebc1c5c92675267 /Documentation | |
| parent | d5490dfa35427a2967e00a4c7a1b95fdbc8ede34 (diff) | |
| download | linux-2f4f2f8f860cb4c3336a7435ebe8dcfded0c9c6e.tar.gz linux-2f4f2f8f860cb4c3336a7435ebe8dcfded0c9c6e.tar.bz2 linux-2f4f2f8f860cb4c3336a7435ebe8dcfded0c9c6e.zip | |
x86/vmscape: Enable the mitigation
commit 556c1ad666ad90c50ec8fccb930dd5046cfbecfb upstream.
Enable the previously added mitigation for VMscape. Add the cmdline
vmscape={off|ibpb|force} and sysfs reporting.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Amit Shah <amit.shah@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-devices-system-cpu | 1 | ||||
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 11 |
2 files changed, 12 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index 0301ac606cdd..2c78f932a956 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -526,6 +526,7 @@ What: /sys/devices/system/cpu/vulnerabilities /sys/devices/system/cpu/vulnerabilities/srbds /sys/devices/system/cpu/vulnerabilities/tsa /sys/devices/system/cpu/vulnerabilities/tsx_async_abort + /sys/devices/system/cpu/vulnerabilities/vmscape Date: January 2018 Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> Description: Information about CPU vulnerabilities diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index f12ba5c12b91..25e07ac5c1ca 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3107,6 +3107,7 @@ ssbd=force-off [ARM64] nospectre_bhb [ARM64] tsx_async_abort=off [X86] + vmscape=off [X86] Exceptions: This does not have any effect on @@ -6399,6 +6400,16 @@ vmpoff= [KNL,S390] Perform z/VM CP command after power off. Format: <command> + vmscape= [X86] Controls mitigation for VMscape attacks. + VMscape attacks can leak information from a userspace + hypervisor to a guest via speculative side-channels. + + off - disable the mitigation + ibpb - use Indirect Branch Prediction Barrier + (IBPB) mitigation (default) + force - force vulnerability detection even on + unaffected processors + vsyscall= [X86-64] Controls the behavior of vsyscalls (i.e. calls to fixed addresses of 0xffffffffff600x00 from legacy |