Message-ID: <1514625242.2379.4.camel@tsoy.me>
Subject: Re: 4.14.9 doesn't boot (regression)
From: Alexander Tsoy <alexander@tsoy.me>
To: Linus Torvalds <torvalds@linux-foundation.org>,
        Andy Lutomirski <luto@amacapital.net>,
        Dave Hansen <dave.hansen@intel.com>
Cc: Toralf =?ISO-8859-1?Q?F=F6rster?= <toralf.foerster@gmx.de>,
        stable <stable@vger.kernel.org>,
        Linux Kernel <linux-kernel@vger.kernel.org>,
        the arch/x86 maintainers <x86@kernel.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>
Date: Sat, 30 Dec 2017 12:14:02 +0300
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В Пт, 29/12/2017 в 17:34 -0800, Linus Torvalds пишет:
> On Fri, Dec 29, 2017 at 5:00 PM, Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
> > 
> > Good. I was not feeling so happy about this bug report, but now I
> > can
> > firmly just blame the gentoo compiler for having some shit-for-
> > brains
> > "feature".
> 
> Looks like I can generate similar bad code with the F26 version of
> gcc, it's just not enabled by default.
> 
> So all gentoo did was change the default options.

Yes, and only in hardened profile, so most users don't have -fstack-
check by default. :)

> 
> I suspect we should just add a
> 
>     KBUILD_CFLAGS  += $(call cc-option,-fno-stack-check,)
> 
> somewhere to the main Makefile, just to make sure.
> 
> Maybe like the appended?
> 
> Toralf, Alexander, does this make things JustWork(tm) for you?

I can confirm that with your patch my gcc produces working kernel.