2022-06-24 01:42:07

by Liu Song

Subject: [PATCH] arm64: correct the effect of mitigations off on kpti

From: Liu Song <[email protected]>

If KASLR is enabled, then kpti will be forced to be enabled even if
mitigations off, so we need to adjust the description of this parameter.

Signed-off-by: Liu Song <[email protected]>
---
Documentation/admin-guide/kernel-parameters.txt | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 8090130..5b9e7f3 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3162,7 +3162,7 @@
improves system performance, but it may also
expose users to several CPU vulnerabilities.
Equivalent to: nopti [X86,PPC]
- kpti=0 [ARM64]
+ if nokaslr then kpti=0 [ARM64]
nospectre_v1 [X86,PPC]
nobp=0 [S390]
nospectre_v2 [X86,PPC,S390,ARM64]
--
1.8.3.1

2022-06-28 17:43:15

by Will Deacon

Subject: Re: [PATCH] arm64: correct the effect of mitigations off on kpti

On Fri, 24 Jun 2022 09:20:48 +0800, Liu Song wrote:
> From: Liu Song <[email protected]>
>
> If KASLR is enabled, then kpti will be forced to be enabled even if
> mitigations off, so we need to adjust the description of this parameter.
>
>

Applied to arm64 (for-next/kpti), thanks!

[1/1] arm64: correct the effect of mitigations off on kpti
https://git.kernel.org/arm64/c/e92b25731ef6

Cheers,
--
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev