Re: [Qemu-devel] [PATCH] e1000e: Don't zero out buffer address in rx descriptor

[Jason Wang <jasowang@redhat.com>]

On 2016年10月18日 22:27, Kevin Wolf wrote:
> Am 18.10.2016 um 16:10 hat Dmitry Fleytman geschrieben:
>> >     On 17 Oct 2016, at 01:35 AM, Kevin Wolf<mail@kevin-wolf.de>  wrote:
>> >
>> >     The e1000e emulation zeroes out any used rx descriptor and then writes a
>> >     completely newly constructed value there. By doing this, it doesn't only
>> >     update the write-back area of the descriptors (as it's supposed to do),
>> >     but it also clears the buffer address, which real hardware doesn't do.
>> >
>> >     The spec explicitly mentions in chapter 7.1.8 that it is valid for a
>> >     driver to reuse a descriptor and only update the status field while
>> >     doing so, i.e. reusing the old buffer address:
>> >
>> >        If software statically allocates buffers, and uses memory read to
>> >        check for completed descriptors, it simply has to zero the status
>> >        byte in the descriptor to make it ready for reuse by hardware.
>> >
>> >     This patch fixes the behaviour to leave the buffer address in
>> >     descriptors unchanged even after the descriptor has been used.
>> >
>> >
>> >Hi Kevin,
>> >
>> >Reviewed-by: Dmitry Fleytman<dmitry@daynix.com>
>> >
>> >Thanks for catching this!
> Thanks, Dmitry!
>
> I assume that your R-b implies that you don't send a pull request
> yourself. If so, what's the process for getting the patch merged? Is
> Jason going to pick it up normally or should I send a pull request of my
> own?
>

I've picked this in my tree.

Thanks