This bug is awaiting verification that the linux- aws-5.15/5.15.0-1046.51~20.04.1 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-focal-linux- aws-5.15' to 'verification-done-focal-linux-aws-5.15'. If the problem still exists, change the tag 'verification-needed-focal-linux-aws-5.15' to 'verification-failed-focal-linux-aws-5.15'.
If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you! ** Tags added: kernel-spammed-focal-linux-aws-5.15-v2 verification-needed-focal-linux-aws-5.15 -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-aws in Ubuntu. https://bugs.launchpad.net/bugs/2004807 Title: RDMA Back port DMA buffer fix Status in linux-aws package in Ubuntu: Fix Released Status in linux-aws source package in Focal: Fix Released Status in linux-aws source package in Jammy: Fix Released Status in linux-aws source package in Kinetic: Fix Released Bug description: SRU Justification [Impact] When registering a new DMA MR after selecting the best aligned page size for it, we iterate over the given sglist to split each entry to smaller, aligned to the selected page size, DMA blocks. In given circumstances where the sg entry and page size fit certain sizes and the sg entry is not aligned to the selected page size, the total size of the aligned pages we need to cover the sg entry is >= 4GB. Under this circumstances, while iterating page aligned blocks, the counter responsible for counting how much we advanced from the start of the sg entry is overflowed because its type is u32 and we pass 4GB in size. This can lead to an infinite loop inside the iterator function because the overflow prevents the counter to be larger than the size of the sg entry. Fixes: a808273 ("RDMA/verbs: Add a DMA iterator to return aligned contiguous memory blocks") [Test Plan] AWS tested [Where things could go wrong] What could possibly go wrong with Remote DMA scatter/gather list errors ? [Other Info] SF: #00353710 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-aws/+bug/2004807/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp