linux-kernel - Re: [PATCH v3 1/3] x86/64: Make kernel text mapping always take one whole page table in early boot code

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Date:   Thu, 5 Jan 2017 15:01:12 +0100
From:   Borislav Petkov <bp@...e.de>
To:     Baoquan He <bhe@...hat.com>, "H. Peter Anvin" <hpa@...or.com>
Cc:     tglx@...utronix.de, mingo@...hat.com, linux-kernel@...r.kernel.org,
        x86@...nel.org, yinghai@...nel.org, thgarnie@...gle.com,
        kuleshovmail@...il.com, luto@...nel.org, mcgrof@...nel.org,
        anderson@...hat.com, dyoung@...hat.com
Subject: Re: [PATCH v3 1/3] x86/64: Make kernel text mapping always take one
 whole page table in early boot code

On Thu, Jan 05, 2017 at 11:28:00AM +0800, Baoquan He wrote:
> Possibly people worry more that no enough space left for kernel modules
> mapping whthin 1G, just a guess. I am fine with making text mapping size
> 1G by default. Kees must know more about the 1G only if kaslr enabled.

So I'm thinking practically kaslr will be enabled on the majority
of the systems anyway so we will have 1G text mapping size on most.
The question is, are there any downsides/issues with making that the
default.

hpa, do you see any problems with it?

Thanks.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
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