linux-kernel - Re: [GIT PULL] x86/mm changes for v4.4

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Message-ID: <20151105222747.GG3579@pd.tnic>
Date:	Thu, 5 Nov 2015 23:27:47 +0100
From:	Borislav Petkov <bp@...en8.de>
To:	Linus Torvalds <torvalds@...ux-foundation.org>
Cc:	Dave Jones <davej@...emonkey.org.uk>,
	Ingo Molnar <mingo@...nel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	"H. Peter Anvin" <hpa@...or.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Andy Lutomirski <luto@...nel.org>,
	Denys Vlasenko <dvlasenk@...hat.com>
Subject: Re: [GIT PULL] x86/mm changes for v4.4

On Thu, Nov 05, 2015 at 02:04:55PM -0800, Linus Torvalds wrote:
> and there's quite a few other pages there that are RW but not marked
> NX. I suspect they come from the EFI runtime services because the

Yeah, at least the EFI mappings would need a bit more fiddling until
they're NX:

https://lkml.kernel.org/r/20151012124113.GD2579@codeblueprint.co.uk

Perhaps we don't even have to make them NX - just set the PGD entry
containing them before the EFI call and unset it after its done.
I.e., something like that.

> pattern seems to match what I see in that area, but there's at least a
> PSE mapping at START_KERNEL_map too, etc.

Maybe we should default n CONFIG_DEBUG_WX until stuff has been fixed...?

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.
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