linux-kernel - Re: [PATCH v2 2/2] x86/boot/64: round memory hole size up to next PMD page.

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Message-ID: <20190924194819.GB8138@swahl-linux>
Date:   Tue, 24 Sep 2019 14:48:19 -0500
From:   Steve Wahl <steve.wahl@....com>
To:     Dave Hansen <dave.hansen@...el.com>
Cc:     Steve Wahl <steve.wahl@....com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        "H. Peter Anvin" <hpa@...or.com>, x86@...nel.org,
        Juergen Gross <jgross@...e.com>,
        "Kirill A. Shutemov" <kirill@...temov.name>,
        Brijesh Singh <brijesh.singh@....com>,
        Jordan Borgner <mail@...dan-borgner.de>,
        Feng Tang <feng.tang@...el.com>, linux-kernel@...r.kernel.org,
        Chao Fan <fanc.fnst@...fujitsu.com>,
        Zhenzhong Duan <zhenzhong.duan@...cle.com>,
        Baoquan He <bhe@...hat.com>, russ.anderson@....com,
        dimitri.sivanich@....com, mike.travis@....com
Subject: Re: [PATCH v2 2/2] x86/boot/64: round memory hole size up to next
 PMD page.

On Mon, Sep 23, 2019 at 02:20:35PM -0700, Dave Hansen wrote:
> On 9/23/19 11:15 AM, Steve Wahl wrote:
> > The kernel image map is created using PMD pages, which can include
> > some extra space beyond what's actually needed.  Round the size of the
> > memory hole we search for up to the next PMD boundary, to be certain
> > all of the space to be mapped is usable RAM and includes no reserved
> > areas.
> 
> This looks good.  It also fully closes any possibility that anyone's
> future hardware will hit issues like this as long as they mark the
> memory reserved, right?

I believe that is true.  Thanks!

> Reviewed-by: Dave Hansen <dave.hansen@...ux.intel.com>

--> Steve Wahl

-- 
Steve Wahl, Hewlett Packard Enterprise