Re: [PATCH] mm/hmm: Allow hmm_dma_map_alloc() to tolerate NULL device

Christoph Hellwig
2025-05-23T14:48:17Z

On Fri, May 23, 2025 at 02:35:37PM +0000, Daisuke Matsuda wrote:
> Some drivers (such as rxe) may legitimately call hmm_dma_map_alloc() with a
> NULL device pointer,

No, they may not. If something has no device with physical DMA
capabilities, it has not business calling into it.