From mboxrd@z Thu Jan  1 00:00:00 1970
From: dingtianhong@huawei.com (Ding Tianhong)
Date: Thu, 15 Jan 2015 20:56:21 +0800
Subject: [PATCH net-next v13 0/3] add hisilicon hip04 ethernet driver
In-Reply-To: <54B7B4E7.8030108@suse.de>
References: <1421217254-12008-1-git-send-email-dingtianhong@huawei.com>
 <54B642B4.8010807@suse.de> <54B77C43.6010200@huawei.com>
 <14674609.dERhba4yMV@wuerfel> <54B7B4E7.8030108@suse.de>
Message-ID: <54B7B8F5.6060808@huawei.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On 2015/1/15 20:39, Alexander Graf wrote:
> 
> 
> On 15.01.15 10:42, Arnd Bergmann wrote:
>> On Thursday 15 January 2015 16:37:23 Ding Tianhong wrote:
>>> On 2015/1/14 18:19, Alexander Graf wrote:
>>>>
>>>> >From a 10000 feet perspective it looks like two problems to me
>>>>
>>>>   1) Allocation failure doesn't get handled properly somewhere
>>
>> This is the bug that Eric pointed out as well.
>>
>>>>   2) We fail to allocate with order=0 - I don't see why
>>
>> GFP_ATOMIC. When allocating from a the napi poll function in softirq
>> context, you have to use nonblocking allocations, which occasionally
>> fail. This should not cause any harm other than dropped packets.
>>
>>> is it easy to repetition this bug? how big is your memory on your board,
>>> is it happened in your previous hip04 driver?
>>
>> It should be independent of memory size, but may be more likely if you
>> don't have swap space configured.
> 
> With the previous driver I was unable to get this far - I ended up in
> random memory corruption and had a ~90% packet loss after about an hour
> of uptime.
> 
> I'm not sure whether it's easy to reproduce, I merely started up a few
> VMs, did some disk I/O and started to compile QEMU in the background ;).
> 
> I'll happily give your follow up patch that's going to fix the memory
> allocation problems a try though.
> 
Thanks for your work, I am sure we could make it much more better:)

Ding

> 
> Alex
> 
> .
>