This commit appeared now in v5.15.46, which will be handled in the next weeks by the kernel team.
But I change the title to 22.04, since 21.10 is EOL as of today, and this patch is not in jammy. It got upstream accepted with v5.19-rc1 hence no need to patch kinetic, since kinetic's target kernel is 5.19. ** Changed in: ubuntu-z-systems Status: New => Triaged ** Changed in: linux (Ubuntu) Status: New => Triaged ** Also affects: linux (Ubuntu Jammy) Importance: Undecided Status: New ** Changed in: linux (Ubuntu Jammy) Status: New => Triaged ** Changed in: linux (Ubuntu) Status: Triaged => Invalid ** Changed in: linux (Ubuntu Jammy) Assignee: (unassigned) => Skipper Bug Screeners (skipper-screen-team) ** Changed in: linux (Ubuntu) Assignee: Skipper Bug Screeners (skipper-screen-team) => (unassigned) -- 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/1977962 Title: [UBUNTU 21.10] s390/perf: obtain sie_block from the right address Status in Ubuntu on IBM z Systems: Triaged Status in linux package in Ubuntu: Invalid Status in linux source package in Jammy: Triaged Bug description: Description: s390/perf: obtain sie_block from the right address Symptom: Read from unitialized stack memory, incorrect guest perf data reported, possibly system crash. Problem: When perf is instructed to record a software-based event and to trace the guest, i.e. using the following command: perf kvm --guest --guestvmlinux=endless.elf top -e cpu-clock The reported guest instruction pointer is inaccurate or the system may crash. This is caused by the sie_block being taken from empty1[0] in sie_block() in arch/s390/kernel/perf_event.c, but since 1179f170b6f0 ("s390: fix fpu restore in entry.S") it resides at empty1[1]. Solution: Obtain sie_block from the right address in sie_block(). Reproduction: 1. Start a KVM guest executing an endless loop. 2. Determine the instruction address of the loop. 3. Start perf recording for any software event and trace the guest, for example using this command: perf kvm --guest --guestvmlinux=endless.elf top -e cpu-clock 4. The reported guest instruction addresses don't match the loop's instruction address or the system crashes. Upstream-ID: c9bfb460c3e4da2462e16b0f0b200990b36b1dd2 BBPF Probl.ID: 198450 Preventive: yes Reported: - SupportTicket: - Reference: - Date: 2022-06-02 Author: n...@linux.ibm.com Component: kernel Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c9bfb460c3e4da2462e16b0f0b200990b36b1dd2 Problem occurs / affects impish and jammy To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1977962/+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