Re: [PATCH v2 ath-next 2/2] wifi: ath11k: fix HTC rx insufficient length

[Miaoqing Pan <quic_miaoqing@quicinc.com>]

On 3/13/2025 11:57 PM, Johan Hovold wrote:
> On Thu, Mar 13, 2025 at 09:41:51AM +0800, Miaoqing Pan wrote:
>> On 3/13/2025 12:43 AM, Johan Hovold wrote:
> 
>>> I've taken a closer look at the driver and it seems like we're missing a
>>> read barrier to make sure that the updated descriptor is not read until
>>> after the head pointer.
>>>
>>> Miaoqing, could you try the below patch with your reproducer and see if
>>> it is enough to fix the corruption?
>>
>> Sure, the stress test is running.
> 
> Thanks.
> 
>>> If so I can resend with the warning removed and include a corresponding
>>> fix for ath12k (it looks like there are further places where barriers
>>> are missing too).
> 
>> If the DMA read barrier works, do you think my submitted patch series is
>> still needed? Because the error handling is incorrect.
> 
> Yeah, it would still be good to fix up the error handling even if you
> don't expect to ever see a descriptor with length 0.
> 
> But unless the device is doing something wrong here, there shouldn't be
> a need for peeking at the descriptor and retrying.
> 
> Johan

New version will be submitted based on the previous discussion.