diff options
| author | Marc Zyngier <marc.zyngier@arm.com> | 2018-07-20 10:56:25 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-07-22 14:27:41 +0200 |
| commit | 3a64e6a9989e0748ff17b6deeec659cb1a3e1938 (patch) | |
| tree | 5a03eb58d15d7b452cb65251b0a85e7adada68f0 /Documentation | |
| parent | e7037bd9fc07329f8a2e6383c65876a35ba33a12 (diff) | |
arm64: Add 'ssbd' command-line option
commit a43ae4dfe56a01f5b98ba0cb2f784b6a43bafcc6 upstream.
On a system where the firmware implements ARCH_WORKAROUND_2,
it may be useful to either permanently enable or disable the
workaround for cases where the user decides that they'd rather
not get a trap overhead, and keep the mitigation permanently
on or off instead of switching it on exception entry/exit.
In any case, default to the mitigation being enabled.
Reviewed-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/kernel-parameters.txt | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 52240a63132e..a16f87e4dd10 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -4023,6 +4023,23 @@ bytes respectively. Such letter suffixes can also be entirely omitted. spia_pedr= spia_peddr= + ssbd= [ARM64,HW] + Speculative Store Bypass Disable control + + On CPUs that are vulnerable to the Speculative + Store Bypass vulnerability and offer a + firmware based mitigation, this parameter + indicates how the mitigation should be used: + + force-on: Unconditionally enable mitigation for + for both kernel and userspace + force-off: Unconditionally disable mitigation for + for both kernel and userspace + kernel: Always enable mitigation in the + kernel, and offer a prctl interface + to allow userspace to register its + interest in being mitigated too. + stack_guard_gap= [MM] override the default stack gap protection. The value is in page units and it defines how many pages prior |