Re: [PATCH] mm: kfence: Fix false positives on big endian
From: Alexander Potapenko <glider@google.com>
Date: 2023-05-05 07:15:08
Also in:
linux-mm
On Fri, May 5, 2023 at 5:51 AM Michael Ellerman [off-list ref] wrote:
Since commit 1ba3cbf3ec3b ("mm: kfence: improve the performance of
__kfence_alloc() and __kfence_free()"), kfence reports failures in
random places at boot on big endian machines.
The problem is that the new KFENCE_CANARY_PATTERN_U64 encodes the
address of each byte in its value, so it needs to be byte swapped on big
endian machines.
The compiler is smart enough to do the le64_to_cpu() at compile time, so
there is no runtime overhead.
Fixes: 1ba3cbf3ec3b ("mm: kfence: improve the performance of
__kfence_alloc() and __kfence_free()")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>Reviewed-by: Alexander Potapenko <glider@google.com>