On Thu, Apr 18, 2019 at 12:22:55PM -0400, tedheadster wrote: > 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. Please just submit them with that rationale directly to the stable team. Although they will probably ask for a commit that introduce the behavior unless they weakend their criteria for stable inclusion.
