On Wed, Sep 20, 2017 at 07:58:34PM +0900, Masahiro Yamada wrote:

2017-09-08 1:46 GMT+09:00 Catalin Marinas [off-list ref]:

quoted

On Thu, Aug 31, 2017 at 06:56:23PM +0900, Masahiro Yamada wrote:

quoted

Aarch64 instructions must be word aligned.  The current 16 byte
alignment is more than enough.  Relax it into 4 byte alignment.

Signed-off-by: Masahiro Yamada <redacted>
---

I do not know why arm64 Linux requires 16 byte alignment.

I dug git-history of arch/arm64/include/asm/linkage.h
and the only commit I see is:

  commit aeed41a9371ee02257b608eb06a9058507a7d0f4
  Author: Marc Zyngier [off-list ref]
  Date:   Fri Oct 19 17:33:27 2012 +0100

      arm64: fix alignment padding in assembly code

It just opt out of the asm-generic variant to remove 0x90.
So, the amount of alignment might not be not optimized yet.

Please correct me if I am missing something.

Not sure why we ended up with 4. Possibly because we forgot the power of
2 difference for arm/arm64.

Queued for 4.14. Thanks.

I still do not see this patch in linux-next.

It won't make it into linux-next now, I'll push it as a fix for -rc2
(sorry, I've been away at Plumbers and didn't get the chance to send any
pull request). I'll push the patch out on fixes/core once I investigate
some unrelated failures.

-- 
Catalin