On Sun, May 28, 2023 at 11:07:40PM +0300, Baruch Even wrote: > Hi, > We found an issue with newer kernels (5.13+) that are found on newer > OSes (Ubuntu22, Rocky9, Ubuntu20 with kernel 5.15) where a 2M page that > was allocated for DPDK was migrated (moved into another physical page) > when a 1G page was allocated. > From our reading of the kernel commits this started with commit > ae37c7ff79f1f030e28ec76c46ee032f8fd07607 > mm: make alloc_contig_range handle in-use hugetlb pages > This caused what looked like memory corruptions to us and cases where > the rings were moved from their physical location and communication was > no longer possible. > I wanted to ask if anyone else hit this issue and what mitigations are > available? > We are currently looking at using a kernel driver to pin the pages but > I expect that this issue will affect others and that a more general > approach is needed. > Thanks, > Baruch > --
Hi, what kernel driver was being used for the device I/O part? Was it a UIO based driver or "vfio-pci"? When using vfio-pci and configuring IOMMU mappings, the pages mapped should be pinned by the kernel, I would have thought, since the kernel knows they are being used by devices. /Bruce
