lkml.org 
[lkml]   [2015]   [Jun]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH] stmmac: explicitly zero des0 & des1 on init
From
From: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Date: Tue, 16 Jun 2015 20:40:41 +0300

> Current implementtion of descriptor init procedure only takes care about
> ownership flag. While it is perfectly possible to have underlying memory
> filled with garbage on boot or driver installation.
>
> And randomly set flags in non-zeroed des0 and des1 fields may lead to
> unpredictable behavior of the GMAC DMA block.
>
> Solution to this problem is as simple as explicit zeroing of both des0
> and des1 fields of all buffer descriptors.
>
> Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>

If you need the memory zero initialized, use dma_zalloc_coherent().
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2015-06-21 18:41    [W:0.068 / U:0.048 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site