Messages in this thread | | | From | Arnd Bergmann <> | Date | Wed, 13 Oct 2021 09:55:14 +0200 | Subject | Re: [PATCH 1/3] arm64: vdso32: drop the test for dmb ishld |
| |
On Wed, Oct 13, 2021 at 1:46 AM Nick Desaulniers <ndesaulniers@google.com> wrote: > > Binutils added support for this instruction in commit > e797f7e0b2bedc9328d4a9a0ebc63ca7a2dbbebc which shipped in 2.34 (just > missing the 2.33 release) but was cherry-picked into 2.33 in commit > 27a50d6755bae906bc73b4ec1a8b448467f0bea1. Thanks to Christian and Simon > for helping me with the patch archaeology. > > According to Documentation/process/changes.rst, the minimum supported > version of binutils is 2.33. Since all supported versions of GAS support > this instruction, drop the assembler invocation, preprocessor > flags/guards, and the cross assembler macro that's now unused. > > This also avoids a recursive self reference in a follow up cleanup > patch. > > Cc: Christian Biesinger <cbiesinger@google.com> > Cc: Simon Marchi <simon.marchi@polymtl.ca> > Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
This change looks good, but I think we should do the same for the gcc version check:
> -#if __LINUX_ARM_ARCH__ >= 8 && defined(CONFIG_AS_DMB_ISHLD) > +#if __LINUX_ARM_ARCH__ >= 8 > #define aarch32_smp_mb() dmb(ish) > #define aarch32_smp_rmb() dmb(ishld) > #define aarch32_smp_wmb() dmb(ishst)
gcc-4.8 already supported -march=armv8, and we require gcc-5.1 now, so both this #if/#else construct and the corresponding "cc32-option,-march=armv8-a" check should be obsolete now.
Arnd
| |