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	Tue, 29 Aug 2023 19:17:14 +0700 (WIB)
Date: Tue, 29 Aug 2023 19:17:10 +0700
From: Ammar Faizi <ammarfaizi2@gnuweeb.org>
To: Willy Tarreau <w@1wt.eu>
Cc: Thomas =?iso-8859-1?Q?Wei=DFschuh?= <linux@weissschuh.net>,
	Zhangjin Wu <falcon@tinylab.org>,
	Nicholas Rosenberg <inori@vnlx.org>,
	Michael William Jonathan <moe@gnuweeb.org>,
	GNU/Weeb Mailing List <gwml@vger.gnuweeb.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 1/1] tools/nolibc: i386: Fix a stack misalign bug on
 _start
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On Tue, Aug 29, 2023 at 08:21:47AM +0200, Willy Tarreau wrote:
> Indeed, good catch! However if we want to do it cleany (i.e not punch a
> 16 to 28 byes hole in the stack), we should do this instead:
> 
> 		add  $12, %esp   /* the stack must be aligned to 16 ... */
> 		and  $-16, %esp  /* ... bytes after eax is pushed and ... */
> 		sub  $12, %esp   /* ... before the call. */
> 
> This will only add 0 to 12 bytes depending on the existing alignment.
> 
> What do you think ?

Good point. I'll send a v3 revision tomorrow.

I just saw that Linus has pulled the PR from Shuah that contains this
bug. IOW, I missed this fix for the 6.6 merge window. Let's see if it
can go to 6.6-rc2. Or maybe sooner than that.

-- 
Ammar Faizi