Hi, On Fri, 4 Nov 2022, Takashi Iwai wrote: > On Fri, 04 Nov 2022 16:42:29 +0100, Kai Vehmanen wrote: > > I think an explicit error would be best. The problem now is that the > > driver will think the allocation (and mapping to device) is fine and > > proceeds to program the hardware to use the address. This will then create > > an IOMMU fault down the line that is not so straighforward to recover from > > (worst case is that a full device level reset needs to be done). And given > > driver doesn't know it got a faulty mapping, it's hard to make the > > decision why the fault happened. > > OK, then what I posted in another mail (it went to nirvana) might > work. Attached below again. thanks! Let me put this through testing and get back to you next week. We'll also debug a bit more what exactly goes on that leads to dma_alloc_noncontiguous failing. Br, Kai
