[PATCH v2] wifi: mt76: fix potential memory leakage

[Felix Fietkau]

Hi Sujuan,

> Yes, it is so expensive, but if no memcopy, it will casue memory
> fragmentation (we hit this issue in internal SQC).
> 
> as we know, wed needs to exchange rx pkt(belongs to wed rx buffer
> manager) with wifi driver(dma rx data queue) by exchanging wfdma dmad
> to ensure the free wed rx buffer.
> 
> it is possiable that a large number of buffer has been exchanged to wed
> and can not come back to wlan driver. So, the memory from the same 32K
> page cache is unable to be released, and it will be failed at
> page_frag_alloc in mt76_dma_rx_fill.
> 
> Any ideas but memcopy?
A simple solution would be to simply allocate single pages, or half-page fragments.

- Felix