Jerome Pouiller <Jerome.Pouiller@xxxxxxxxxx> writes: > +/* > + * Internal helpers. > + * > + * About CONFIG_VMAP_STACK: > + * When CONFIG_VMAP_STACK is enabled, it is not possible to run DMA on stack > + * allocated data. Functions below that work with registers (aka functions > + * ending with "32") automatically reallocate buffers with kmalloc. However, > + * functions that work with arbitrary length buffers let's caller to handle > + * memory location. In doubt, enable CONFIG_DEBUG_SG to detect badly located > + * buffer. > + */ This sounds very hacky to me, I have understood that you should never use stack with DMA. -- https://patchwork.kernel.org/project/linux-wireless/list/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
