Re: [PATCH] powerpc/uaccess: Perform barrier_nospec() in KUAP allowance helpers
From: Michael Ellerman <hidden>
Date: 2021-02-10 13:03:16
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On Sun, 7 Feb 2021 10:08:11 +0000 (UTC), Christophe Leroy wrote:
barrier_nospec() in uaccess helpers is there to protect against speculative accesses around access_ok(). When using user_access_begin() sequences together with unsafe_get_user() like macros, barrier_nospec() is called for every single read although we know the access_ok() is done onece. [...]
Applied to powerpc/next.
[1/1] powerpc/uaccess: Perform barrier_nospec() in KUAP allowance helpers
https://git.kernel.org/powerpc/c/8524e2e76441fc615a3b5c1415823e051cc79eae
cheers