On Thu, Apr 18, 2019 at 12:16 PM Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > > On Wed, Apr 17, 2019 at 02:05:29PM -0400, tedheadster wrote: > > > Christoph, > > > your patch fixed it nicely. No more error messages when I boot with > > > 16GiB enabled on a 32-bit PAE-enabled system. > > > > Christoph, > > can you please submit this patch to be backported to the long-term > > kernels (4.14, 4.9, 4.4, 3.18, and 3.16)? > > My patch that triggered the issue for SCSI was only merges in 4.18. > Do you have other reason why you need swiotlb on the older kernels? Christoph, yes, I test all the long term kernels on a PAE-enabled machine with 16GiB. Performance is horrible without the patch. I get 800-1000 kilobytes/second (not a misspelling) with my locally attached SCSI disk without the patch. With the patch, I get about 25 megabytes/second. - Matthew
