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Date:   Wed, 25 Mar 2020 14:31:37 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Sergei Trofimovich <slyfox@gentoo.org>
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
Message-ID: <20200325133137.GC27261@zn.tnic>
References: <20200314164451.346497-1-slyfox@gentoo.org>
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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?

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette