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Date: Wed, 8 Mar 2017 18:17:50 +0800
From: Baoquan He <bhe@redhat.com>
To: Borislav Petkov <bp@alien8.de>
Cc: Bhupesh Sharma <bhsharma@redhat.com>, Dave Young <dyoung@redhat.com>,
        linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org,
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        Thomas Gleixner <tglx@linutronix.de>, mingo@redhat.com, hpa@zytor.com,
        x86@kernel.org, akpm@linux-foundation.org
Subject: Re: [PATCH 1/2] x86/efi: Correct a tiny mistake in code comment
Message-ID: <20170308101750.GD6570@x1>
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On 03/08/17 at 10:35am, Borislav Petkov wrote:
> On Wed, Mar 08, 2017 at 05:09:55PM +0800, Baoquan He wrote:
> > Yes, it looks better. I can repost with this change. Thanks.
> 
> No it doesn't:

All right, I will just update the code comment. Just back ported kaslr
to our OS product, people reviewed and found the upper boundary of kaslr
mm region is EFI_VA_START, that's not correct, it has to be corrected
firstly in upstream. Then found the confusion in code comment.

Change or keep it, both is fine to me.

Thanks!

> 
> #define EFI_VA_START     ( -4 * (_AC(1, UL) << 30))
> #define EFI_VA_END       (-68 * (_AC(1, UL) << 30))
> 
> That's -4G (the shift by 30) and -68G, respectively.
> 
> > > #define EFI_VA_START    _AC(0xfffffffeffffffff, UL)
> > > #define EFI_VA_END    _AC(0xffffffef00000000, UL)
> 
> That is something which I need to type into a calculator first.
> 
> Can you guys point your attention to something which is really broken
> and stop wasting your time? And there's enough really broken crap left
> and right...
> 
> -- 
> Regards/Gruss,
>     Boris.
> 
> Good mailing practices for 400: avoid top-posting and trim the reply.