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Re: [PATCH] stmmac: explicitly zero des0 & des1 on init

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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().
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[PATCH] stmmac: explicitly zero des0 & des1 on init Alexey Brodkin <Alexey.Brodkin@synopsys.com> - 2015-06-16 19:50 +0200
  Re: [PATCH] stmmac: explicitly zero des0 & des1 on init David Miller <davem@davemloft.net> - 2015-06-21 18:20 +0200
    Re: [PATCH] stmmac: explicitly zero des0 & des1 on init Alexey Brodkin <Alexey.Brodkin@synopsys.com> - 2015-06-22 08:50 +0200

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