linux-kernel - Re: [PATCH v2 04/18] x86/gdt: Put per-cpu GDT remaps in ascending order

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Message-ID: <CALCETrUWJ3ynQKG-5x6YBVkAkvk5VjRiY0Zn1xL07WgUjtbgWQ@mail.gmail.com>
Date:   Wed, 22 Nov 2017 07:26:49 -0800
From:   Andy Lutomirski <luto@...nel.org>
To:     Borislav Petkov <bp@...e.de>
Cc:     Andy Lutomirski <luto@...nel.org>, X86 ML <x86@...nel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Brian Gerst <brgerst@...il.com>,
        Dave Hansen <dave.hansen@...el.com>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        Josh Poimboeuf <jpoimboe@...hat.com>
Subject: Re: [PATCH v2 04/18] x86/gdt: Put per-cpu GDT remaps in ascending order

On Wed, Nov 22, 2017 at 3:05 AM, Borislav Petkov <bp@...e.de> wrote:
> On Tue, Nov 21, 2017 at 08:43:59PM -0800, Andy Lutomirski wrote:
>> We currently have CPU 0's GDT at the top of the GDT range and
>> higher-numbered CPUs at lower addreses.  This happens because the
>> fixmap is upside down (index 0 is the top of the fixmap).
>>
>> Flip it so that GDTs are in ascending order by virtual address.
>> This will simplify a future patch that will generalize the GDT
>> remap to contain multiple pages.
>>
>> Reviewed-by: Thomas Gleixner <tglx@...utronix.de>
>> Signed-off-by: Andy Lutomirski <luto@...nel.org>
>> ---
>>  arch/x86/include/asm/desc.h | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> Same reply as before:
>
> https://lkml.kernel.org/r/20171121171643.jtwbfuvxwi6wecj3@pd.tnic
>

Oops.  Got it this time.