From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH v3] 3c59x: avoid panic in boomerang_start_xmit when
 finding page address:
Date: Fri, 05 Sep 2014 17:24:26 -0700 (PDT)
Message-ID: <20140905.172426.1277528296784403545.davem@davemloft.net>
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From: Neil Horman <nhorman@tuxdriver.com>
Date: Thu,  4 Sep 2014 06:13:38 -0400

> This bug was reported on a very old kernel (RHEL6, 2.6.32-491.el6):
 ...
> But the problem seems to still exist upstream.  It seems on 32 bit kernels
> page_address() can reutrn a NULL value in some circumstances, and the
> pci_map_single api isn't prepared to handle that (on this system it results in a
> bogus pointer deference in nommu_map_page.
> 
> The fix is pretty easy, if we convert the 3c59x driver to use the more
> convieient skb_frag_dma_map api we don't need to find the virtual address of the
> page at all, and page gets mapped to the hardware properly.  Verified to fix the
> problem as described by the reporter.
> 
> Applies to the net tree
> 
> Change Notes:
> 
> v2) Converted PCI_DMA_TODEVICE to DMA_TO_DEVICE.  Thanks Dave!
> 
> v3) Actually Run git commit after making changes to v2 :)
> 
> Signed-off-by: Neil Horman <nhorman@tuxdriver.com>

Applied, thanks Neil.