From: "Mike Frysinger" <vapier.adi@gmail.com>
To: Denys Vlasenko <vda.linux@googlemail.com>
Cc: linux-arch@vger.kernel.org, Russell King <rmk@arm.linux.org.uk>,
David Howells <dhowells@redhat.com>,
Ralf Baechle <ralf@linux-mips.org>,
Lennert Buytenhek <kernel@wantstofly.org>,
Josh Boyer <jwboyer@linux.vnet.ibm.com>,
Paul Mackerras <paulus@samba.org>,
David Woodhouse <dwmw2@infradead.org>,
Andi Kleen <andi@firstfloor.org>,
torvalds@linux-foundation.org, akpm@linux-foundation.org,
Paul Gortmaker <paul.gortmaker@windriver.com>,
linux-embedded@vger.kernel.org, linux-kernel@vger.kernel.org,
Tim Bird <tim.bird@am.sony.com>,
Martin Schwidefsky <schwidefsky@de.ibm.com>,
Dave Miller <davem@davemloft.net>
Subject: Re: [PATCH 5/23] make section names compatible with -ffunction-sections -fdata-sections: blackfin
Date: Tue, 1 Jul 2008 22:09:20 -0400 [thread overview]
Message-ID: <8bd0f97a0807011909i53a347f5me4410a24dd27d5ab@mail.gmail.com> (raw)
In-Reply-To: <200807020208.33302.vda.linux@googlemail.com>
On Tue, Jul 1, 2008 at 8:08 PM, Denys Vlasenko wrote:
> On Wednesday 02 July 2008 00:58, Mike Frysinger wrote:
>> On Tue, Jul 1, 2008 at 8:35 PM, Denys Vlasenko wrote:
>> > The purpose of this patch is to make kernel buildable
>> > with "gcc -ffunction-sections -fdata-sections".
>> > This patch fixes blackfin architecture.
>>
>> the comment right above what you changed says it already works for
>> Blackfin. so you arent fixing it at all.
>> > /* This gets done first, so the glob doesn't suck it in */
>> > . = ALIGN(32);
>> > - *(.data.cacheline_aligned)
>> > + *(.cacheline_aligned.data)
>
> This may pull in an unrelated data object named "cacheline_aligned"
> (say, a static variable in a driver). If that variable is not
> itself aligned to the cacheline size, it will mess up alignment of all
> objects in .data.cacheline_aligned which follow. Not good.
>
> To be safe from such weird and hard to debug problems
> it's better to not use names like .data.XXXX at all.
> I just uniformly renamed al such "special sections"
> in the kernel to .XXXXX.data
you're right of course ... i obviously hadnt thought of this. please
however still abstract this stuff into the common header.
i just tested the current Blackfin kernel and it does build/link/run
fine with -ffunction-sections/-fdata-sections. however, --gc-sections
still causes crashes (but this is because all of the .init.setup
sections are flagged as unused).
-mike
prev parent reply other threads:[~2008-07-02 2:09 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-07-02 0:35 [PATCH 5/23] make section names compatible with -ffunction-sections -fdata-sections: blackfin Denys Vlasenko
2008-07-01 22:58 ` Mike Frysinger
2008-07-02 0:08 ` Denys Vlasenko
2008-07-02 2:09 ` Mike Frysinger [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=8bd0f97a0807011909i53a347f5me4410a24dd27d5ab@mail.gmail.com \
--to=vapier.adi@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=andi@firstfloor.org \
--cc=davem@davemloft.net \
--cc=dhowells@redhat.com \
--cc=dwmw2@infradead.org \
--cc=jwboyer@linux.vnet.ibm.com \
--cc=kernel@wantstofly.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-embedded@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=paul.gortmaker@windriver.com \
--cc=paulus@samba.org \
--cc=ralf@linux-mips.org \
--cc=rmk@arm.linux.org.uk \
--cc=schwidefsky@de.ibm.com \
--cc=tim.bird@am.sony.com \
--cc=torvalds@linux-foundation.org \
--cc=vda.linux@googlemail.com \
/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;
as well as URLs for NNTP newsgroup(s).