Hi, On 11/24/20 11:27 AM, Christoph Hellwig wrote: > On Mon, Nov 23, 2020 at 03:49:09PM +0100, Hans de Goede wrote: >> Hi, >> >> +Cc Christoph Hellwig <hch@xxxxxx> >> >> Christoph, this is still an issue, so I've been looking around a bit and think this >> might have something to do with the dma-mapping-5.10 changes. >> >> Do you have any suggestions to debug this, or is it time to do a git bisect >> on this before 5.10 ships with regression? > > Given that DMAR prefix this seems to be about using intel-iommu + bounce > buffering for external devices. I can't really think of anything specific > in 5.10 related to that, so maybe you'll need to bisect. > > I doub this means we are actually leaking swiotlb buffers, so while > I'm pretty sure we broke something in lower layers this also means > xhci doesn't handle swiotlb operation very gracefully in general. Ok, I've re-arranged my schedule a bit so that I have time to bisect this tomorrow, so with some luck I will be able to provide info on which commit introduced this issue tomorrow around the end of the day. Regards, Hans