On Thu, 3 Jul 2025 at 15:29, Keith Busch kbusch@kernel.org wrote:
On Thu, Jul 03, 2025 at 11:30:42AM +0200, Christoph Hellwig wrote:
I think the idea to reconstruct the dma addresses from PRPs should be considered a failure by now. It works fine for SGLs, but for PRPs we're better off just stashing them away. Bob, can you try
s/Bob/Ben
something like the patch below? To be fully safe it needs a mempool, and it could use some cleanups, but it does pass testing on my setup here, so I'd love to see if if fixes your issue.
I have tested it on my system and can no longer see the regression.
Happy to retest when the patch goes through.
Tested-by: Ben Copeland ben.copeland@linaro.org
Thank you!
Ben
Thanks for confirming.
While this is starting to look a bit messy, I believe it's still an overall win: you've cut down the vector walking in the setup path from 3 to 1, which reduces a non-trivial amount of overhead for even moderately sized IO.