mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: "H. Peter Anvin" <hpa@zytor.com>
To: Josh Poimboeuf <jpoimboe@redhat.com>, Arnd Bergmann <arnd@arndb.de>
Cc: x86@kernel.org, Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Andy Lutomirski <luto@kernel.org>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86: avoid warning for zero-filling .bss
Date: Thu, 17 Nov 2016 16:07:47 -0800	[thread overview]
Message-ID: <adb36672-58cb-e290-9587-99e3ec6d9f0a@zytor.com> (raw)
In-Reply-To: <20161117224445.n3nerymee5jnrq75@treble>

On 11/17/16 14:44, Josh Poimboeuf wrote:
> On Thu, Nov 17, 2016 at 11:32:30PM +0100, Arnd Bergmann wrote:
>> On Thursday, November 17, 2016 3:02:48 PM CET Josh Poimboeuf wrote:
>>> On Wed, Nov 16, 2016 at 03:17:09PM +0100, Arnd Bergmann wrote:
>>>> The latest binutils are warning about a .fill directive with an explicit
>>>> value in a .bss section:
>>>>
>>>> arch/x86/kernel/head_32.S: Assembler messages:
>>>> arch/x86/kernel/head_32.S:677: Warning: ignoring fill value in section `.bss..page_aligned'
>>>> arch/x86/kernel/head_32.S:679: Warning: ignoring fill value in section `.bss..page_aligned'
>>>>
>>>> This comes from the 'ENTRY()' macro padding the space between the symbols
>>>> with 'nop'. Open-coding the .globl directive without the padding
>>>> avoids that warning.
>>>
>>> How is there space between the symbols?  Aren't they already aligned?
>>
>> My understanding is that they are aligned, it's just that gas complains
>> about the .align directive with a nonzero fill value.
> 
> Ah, I see now.  In that case your patch looks fine to me.
> 

Yes, ENTRY() is for code.

	-hpa

      reply	other threads:[~2016-11-18  0:08 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-11-16 14:17 Arnd Bergmann
2016-11-17  7:19 ` [tip:x86/urgent] x86/boot: Avoid " tip-bot for Arnd Bergmann
2016-11-17 21:02 ` [PATCH] x86: avoid " Josh Poimboeuf
2016-11-17 21:19   ` hpa
2016-11-17 22:32   ` Arnd Bergmann
2016-11-17 22:44     ` Josh Poimboeuf
2016-11-18  0:07       ` H. Peter Anvin [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=adb36672-58cb-e290-9587-99e3ec6d9f0a@zytor.com \
    --to=hpa@zytor.com \
    --cc=arnd@arndb.de \
    --cc=jpoimboe@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@kernel.org \
    --cc=mingo@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®