On Wed, Feb 05, 2020 at 10:45:24AM +0530, Kishon Vijay Abraham I wrote: > > Ok, this mostly like means we allocate a swiotlb buffer that isn't > > actually addressable. To verify that can you post the output with the > > first attached patch? If it shows the overflow message added there, > > please try if the second patch fixes it. > > I'm seeing some sort of busy loop after applying your 1st patch. I sent > a SysRq to see where it is stuck And that shows up just with the patch? Really strange as it doesn't change any blockig points. What also is strange is that I don't see any of the warnings that should be there. FYI, the slightly updated version of the patch that went through my testing it here: git://git.infradead.org/users/hch/misc.git swiotlb-debug Gitweb: http://git.infradead.org/users/hch/misc.git/shortlog/refs/heads/swiotlb-debug this also includes what was the second patch in the previous mail. Can you try that branch?