lkml.org 
[lkml]   [2015]   [May]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v9 3/10] x86, asm: Change is_new_memtype_allowed() for WT
On Wed, 13 May 2015, Toshi Kani wrote:

> __ioremap_caller() calls reserve_memtype() to set new_pcm
> (existing map type if any), and then calls
> is_new_memtype_allowed() to verify if converting to new_pcm
> is allowed when pcm (request type) is different from new_pcm.
>
> When WT is requested, the caller expects that writes are
> ordered and uncached. Therefore, this patch changes
> is_new_memtype_allowed() to disallow the following cases.
>
> - If the request is WT, mapping type cannot be WB
> - If the request is WT, mapping type cannot be WC
>
> Signed-off-by: Toshi Kani <toshi.kani@hp.com>

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>


\
 
 \ /
  Last update: 2015-05-22 09:21    [W:0.133 / U:1.032 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site