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Date:   Fri, 17 Apr 2020 12:41:26 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Borislav Petkov <bp@alien8.de>
Cc:     Sergei Trofimovich <slyfox@gentoo.org>,
        Michael Matz <matz@suse.de>, Jakub Jelinek <jakub@redhat.com>,
        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
Subject: Re: [PATCH v2] x86: fix early boot crash on gcc-10
Message-ID: <20200417104126.GX20730@hirez.programming.kicks-ass.net>
References: <20200326223501.GK11398@zn.tnic>
 <20200328084858.421444-1-slyfox@gentoo.org>
 <20200413163540.GD3772@zn.tnic>
 <alpine.LSU.2.21.2004141343370.11688@wotan.suse.de>
 <20200415074842.GA31016@zn.tnic>
 <alpine.LSU.2.21.2004151445520.11688@wotan.suse.de>
 <20200415231930.19755bc7@sf>
 <20200417075739.GA7322@zn.tnic>
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On Fri, Apr 17, 2020 at 09:57:39AM +0200, Borislav Petkov wrote:

> Yeah, Peter and I have been discussing something like the below
> yesterday. I don't like the additional exports too much but would
> disable stack protector only for the one function...

I did do promise you bike-shedding... so here goes :-)

> -obj-$(CONFIG_SMP)		+= smpboot.o
> +
> +nostackprot := $(call cc-option, -fno-stack-protector)
> +CFLAGS_smpboot_aux.o := $(nostackprot)
> +
> +smpboot_all-y			:= smpboot.o smpboot_aux.o

So how about we call that file: smpboot_nostack.c or, since it only has
the one function in: start_secondary.c ?