Hi, You also mentioned qemu in the description, I think what is related (by title and it has your name) is the following series + one fixup:
77280d33b s390x: fix build for --without-default-devices 37fa32de70 s390x/pci: Honor DMA limits set by vfio cd7498d07f s390x/pci: Add routine to get the vfio dma available count 7486a62845 vfio: Find DMA available capability 3ab7a0b40d vfio: Create shared routine for scanning info capabilities 408b55db8b s390x/pci: Move header files to include/hw/s390x 53ba2eee52 linux-headers: update against 5.10-rc1 84567ea763 update-linux-headers: Add vfio_zdev.h That is in qemu 5.2 - and if that "is it" then in Hirsute things are already fixed by now. But that is quite a list and for backports we will need to reduce that to the minimum that is needed. Did you check if you can (or have even a branch somewhere) backport these on top of 4.2 and/or 5.0 ? Also if this shall be an SRU we would need a testcase, is there anything that can be isolated as test instructions? -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1907421 Title: [UBUNTU 21.04] vfio: pass DMA availability information to userspace Status in Ubuntu on IBM z Systems: Confirmed Status in linux package in Ubuntu: Fix Committed Status in linux source package in Focal: Confirmed Status in linux source package in Groovy: Incomplete Status in linux source package in Hirsute: Fix Committed Bug description: Description: vfio: pass DMA availability information to userspace Symptom: vfio-pci device on s390 enters error state Problem: Commit 492855939bdb added a limit to the number of concurrent DMA requests for a vfio container. However, lazy unmapping in s390 can in fact cause quite a large number of outstanding DMA requests to build up prior to being purged, potentially the entire guest DMA space. This results in unexpected errors seen in qemu such as 'VFIO_MAP_DMA failed: No space left on device' Solution: The solution requires a change to both kernel and qemu - For the kernel, add the ability to provide the number of allowable DMA requests via the VFIO_IOMMU_GET_INFO ioctl. Reproduction: Put a vfio-pci device on s390 under I/O load Upstream-ID: a717072007e8aedd3f951726d8cf55454860b30d 7d6e1329652ed971d1b6e0e7bea66fba5044e271 Need also to be integrated into 20.10 and 20.04. OK, just to clarify we don't need to fix bionic for this one, but rather focal (20.04) and groovy (20.10). Furthermore, for 20.04, 20.10 and 21.04 ONLY commit 7d6e1329652ed971d1b6e0e7bea66fba5044e271 is needed, the other was a pre-req that is already present. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1907421/+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
