Message-ID: <1514596414.28262.22.camel@tsoy.me>
Subject: Re: 4.14.9 doesn't boot (regression)
From: Alexander Tsoy <alexander@tsoy.me>
To: Andy Lutomirski <luto@amacapital.net>,
        Linus Torvalds <torvalds@linux-foundation.org>
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>, jpoimboe@redhat.com
Date: Sat, 30 Dec 2017 04:13:34 +0300
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В Пт, 29/12/2017 в 17:10 -0700, Andy Lutomirski пишет:
> 
> Also, you wouldn't happen to be using Gentoo perchance?  I already
> have two reports of a Gentoo system miscompiling the vDSO due to
> Gentoo enabling -fstack-check and GCC generating stack check code
> that is highly suboptimal, actively incorrect, and doesn't even
> manage to check the stack in a particularly helpful way.
> 
> If this is indeed what's going on, I'm going to try to come up with a
> patch to outright fail the build on these buggy systems.  We could
> probably fudge the build options to avoid the problem, but Gentoo
> really just needs fix its toolchain.

You are right, It's due to fstack-check enabled in gentoo's gcc spec.
"-fstack-check=no" in KBUILD_CFLAGS fixed this problem for me. =/