Re: [PATCH net 1/2] r8152: fix the sw rx checksum is unavailable

From: Mark Lord
Date: Thu Nov 24 2016 - 13:50:03 EST

On 16-11-24 01:34 PM, Mark Lord wrote:
>From tracing through the powerpc arch code, this is the buffer that
> is being directly DMA'd into. And the USB layer does an invalidate_dcache
> on that entire buffer before initiating the DMA (confirmed via printk).

Slight correction: the invalidate_dcache_range() is only done when
using kmalloc'd buffers. I have converted the driver here
to use usb_alloc_coherent() instead, so that now gets skipped
since the memory is never cached.