linux-kernel - Re: Linux 5.8-rc1

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Date:   Wed, 17 Jun 2020 00:00:14 +0200
From:   Gabriel C <nix.or.die@...glemail.com>
To:     Arvind Sankar <nivedita@...m.mit.edu>
Cc:     Linus Torvalds <torvalds@...ux-foundation.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Hans de Goede <hdegoede@...hat.com>,
        Borislav Petkov <bp@...en8.de>
Subject: Re: Linux 5.8-rc1

Am Di., 16. Juni 2020 um 23:25 Uhr schrieb Arvind Sankar
<nivedita@...m.mit.edu>:
>
> On Tue, Jun 16, 2020 at 11:17:08PM +0200, Gabriel C wrote:
> > Am Di., 16. Juni 2020 um 22:33 Uhr schrieb Arvind Sankar
> > <nivedita@...m.mit.edu>:
> > >
> > > Can you attach the output of gcc -dumpspecs and gcc -v? I suspect your
> > > compiler enables stack protector by default. My distro compiler does
> > > that too, but not if -ffreestanding is enabled (which it is for the
> > > purgatory).
> > >
> >
> > Files including config uploaded to there:
> >
> > http://crazy.dev.frugalware.org/kernel/
> >
>
> Yeah, your gcc doesn't have the -ffreestanding handling. Mine (from
> gentoo) has this in the -dumpspecs output:
>
> *cc1_options:
> ... %{nostdlib|nodefaultlibs|ffreestanding:-fno-stack-protector} ...
>
> to switch off the default ssp when the standard libraries aren't available.

I wondered what they enable to do that. it turns out it is a custom patch.
While I think having that is not bad, such patches lead to bugs like this one.