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Date:   Thu, 26 Mar 2020 21:54:24 +0000
From:   Sergei Trofimovich <slyfox@gentoo.org>
To:     Borislav Petkov <bp@alien8.de>
Cc:     Jakub Jelinek <jakub@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Andy Lutomirski <luto@kernel.org>, x86@kernel.org,
        Michael Matz <matz@suse.de>
Subject: Re: [PATCH] x86: fix early boot crash on gcc-10
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On Wed, 25 Mar 2020 14:31:37 +0100
Borislav Petkov <bp@alien8.de> wrote:

> On Tue, Mar 17, 2020 at 03:49:42PM +0100, Borislav Petkov wrote:
> > On Tue, Mar 17, 2020 at 03:39:14PM +0100, Jakub Jelinek wrote:  
> > > That is because the option is called -fno-stack-protector, so one needs to
> > > use __attribute__((optimize("no-stack-protector")))  
> > 
> > Ha, that works even! :-)
> > 
> > And my guest boots.
> > 
> > I guess we can do that then. Looks like the optimal solution to me.
> > 
> > Also, I'm assuming older gccs will simply ignore unknown optimize
> > options?  
> 
> Sergei,
> 
> wanna send v2 where you add the function attribute to start_secondary()
> only instead?

Will attempt to write, test and send out the patch by tomorrow.

-- 

  Sergei