[PATCH ath-next] wifi: ath12k: change MAC buffer ring size to 4096

[Jeff Johnson]

On 10/22/2026 8:44 PM, Shawn Guo wrote:
> + Jeff
> 
> On Fri, Oct 23, 2026 at 11:13:56AM +0800, Baochen Qiang wrote:
>>
>>
>> On 10/23/2026 10:43 AM, Shawn Guo wrote:
>>> On Fri, Oct 23, 2026 at 10:13:18AM +0800, Baochen Qiang wrote:
>>>> On 10/22/2026 9:44 PM, Shawn Guo wrote:
>>>
>>> [...]
>>>
>>>>> I bisected drivers/net/wireless/ath/ath12k between v7.3 (broken) and
>>>>> the ath tag (working). It lands on:
>>>>>
>>>>>   15f7603b69a8 ("wifi: ath12k: Increase RXDMA buffer ring size for default memory profile")
>>>>>
>>>>> The previous commit, 643f0bf93617, still has 4096 entries and is broken.
>>>>> 15f7603b69a8 changes one line, .rxdma_buf_ring_size from 4096 to 8192,
>>>>> and works.
>>>>
>>>> thanks for sharing this. I can repro it using the 481 firmware once get 15f7603b69a8 reverted.
>>>
>>> Thanks for confirming!
>>>
>>>> so the rule here seems that rxdma_buf_ring_size must be at least twice as large as
>>>> DP_RX_MAC_BUF_RING_SIZE (I also tries four times large, it works). This rule looks
>>>> reasonable to me, since WCN7850 get twos HW MACs and its firmware setups rx_mac_buf ring
>>>> for each, and each ring fills itself using the buffers all from the single RXDMA buffer ring.
>>>>
>>>> maybe I should submit a patch mandate this rule.
>>>
>>> I'm more concerned about how we would fix the regression for 7.3.x stable
>>> kernel.
>>
>> we can try to ask stable team to backport 15f7603b69a8 ?
> 
> Ok, I can do the backport after the commit lands mainline, assuming it's
> part of Jeff's PR for 7.4 merge window.
It's in Linus' tree now
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=15f7603b69a83a0acc7fcc8992ecbea6110f9424

Would obviously need to backport the entire series:
https://lore.kernel.org/all/20261007-mpp_ws-v1-0-739b1fb87d24@oss.qualcomm.com/

/jeff