On Tue, May 30, 2023 at 11:04 AM Bruce Richardson < bruce.richardson@intel.com> wrote: > 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 > This was using igb_uio on an AWS instance with their ena driver. Baruch -- Baruch Even Platform Technical Lead, WEKA E baruch@weka.io* ­*W www.weka.io * ­* * ­*