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Date:   Tue, 21 Jul 2020 11:09:01 +0200
From:   Joerg Roedel <joro@8bytes.org>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     Arvind Sankar <nivedita@alum.mit.edu>, hpa@zytor.com,
        Andy Lutomirski <luto@amacapital.net>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        x86@kernel.org, Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Joerg Roedel <jroedel@suse.de>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86/idt: Make sure idt_table takes a whole page
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On Mon, Jul 20, 2020 at 06:48:03PM +0200, Thomas Gleixner wrote:
> But with explicit sections which store only page aligned objects there
> is an implicit guarantee that the object is alone in the page in which
> it is placed. That works for all objects except the last one. That's
> inconsistent.
> 
> By enforcing page sized objects for this section you might also wreckage
> memory sanitizers, because your object is artificially larger than it
> should be and out of bound access becomes legit.

Okay, valid points about the consistency and the memory sanitizers. I'll
submit a patch for the linker scripts soon.

Regards,

	Joerg