Hello Nico, thanks for raising this. The fix/patch c3f0e5fd2d33 "KVM: s390: pv: don't present the ecall interrupt twice" got upstream accepted with kernel v6.0, so I assume that it not only needs to be applied to 20.04/5.4, but also to 22.04/5.15 and 22.10/5.19. And I've noticed that it got nice and properly tagged for upstream stable: Cc: <sta...@vger.kernel.org> # 5.7 Fixes: da24a0cc58ed ("KVM: s390: protvirt: Instruction emulation")
And with that it got already picked up and is included in: 22.04 with Ubuntu-5.15.0-53.59 (currently in jammy-proposed) 22.10 with Ubuntu-5.19.0-16.16 means already incl. in the release kernel. So the only Ubuntu release that is affected is 20.04/focal, so I've set that as affected target series... ** Also affects: linux (Ubuntu Focal) Importance: Undecided Status: New ** Changed in: linux (Ubuntu) Status: New => Invalid ** Changed in: linux (Ubuntu Focal) Status: New => Triaged ** Also affects: ubuntu-z-systems Importance: Undecided Status: New ** Changed in: ubuntu-z-systems Status: New => Triaged ** Changed in: linux (Ubuntu Focal) Assignee: (unassigned) => Skipper Bug Screeners (skipper-screen-team) ** Changed in: linux (Ubuntu) Assignee: Skipper Bug Screeners (skipper-screen-team) => (unassigned) ** Changed in: ubuntu-z-systems Assignee: (unassigned) => Skipper Bug Screeners (skipper-screen-team) -- 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/1995941 Title: [UBUNTU 20.04] KVM: PV: ext call delivered twice when receiver in PSW wait Status in Ubuntu on IBM z Systems: Triaged Status in linux package in Ubuntu: Invalid Status in linux source package in Focal: Triaged Bug description: Description: KVM: PV: ext call delivered twice when receiver in PSW wait Symptom: In a secure execution guest, the external interrupt for the SIGP external call order is delivered twice to a VCPU even though it was only sent once. Problem: Under PV, external call interrupts are delivered by the SIGP interpretation facility, without KVM's involvement. But, if the receiving CPU is in enabled wait, KVM needs to wake the receiving CPU such that the interrupt can be delivered. Hence, in this case, the SIGP external call order causes an interception. In response, KVM only needs to wake the receiving VCPU. Interrupt delivery is then handled by the SIGP interpretation facility. KVM wrongfuly assumed it also needs to request injection for the external call interrupt after the respective intercept, causing the interrupt to be delivered twice: once through the SIGP interpretation facility and once through the interrupt injection control by KVM. Solution: Add appropriate special handling for 108 external call intercepts. Reproduction: 0. Apply kvm-unit-test submitted upstream ("[kvm-unit-tests PATCH v1 0/4] s390x: add tests for SIGP call orders in enabled wait"). 1. Run the smp_PV kvm-unit-test: ./run_tests.sh smp_PV 2. Check logs/smp_PV.log. If system is affected, the following line can be found: ABORT: smp: psw wait: ecall: Unexpected external call \ interrupt (code 0x1202): on cpu 1 at 0x11958 If the system is not affected, the line should look like this: PASS: smp: psw wait: ecall: received Preventive: yes Author: Nico Boehr <n...@linux.ibm.com> Component: kernel To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1995941/+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