------- Comment From boris.m...@de.ibm.com 2022-05-06 12:21 EDT------- Fix released to -updates with last SRU cycle on April 18, hence closing the bug.
Changing Status to: -> CLOSED. -- 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/1962578 Title: [UBUNTU 20.04] Fix SIGP processing on KVM/s390 Status in Ubuntu on IBM z Systems: Fix Released Status in linux package in Ubuntu: Fix Released Status in linux source package in Focal: Fix Released Status in linux source package in Impish: Fix Released Bug description: SRU Justification: ================== [Impact] * The SIGP processing on KVM/s390x is incorrect and not fully conform to the 'Principles of Operations', the IBM Z architecture definition and documentation. * KVM: SIGP RESTART is reporting a CPU state 'stopped' after SIGP RESTART was issued, while it should report a 'busy' condition until the CPU is really started. * The fix for this consists of three patches: 812de04661c4 "KVM: s390: Clarify SIGP orders versus STOP/RESTART" 435d17955519 "KVM: s390: Add a routine for setting userspace CPU state" 4563bcad46bf "KVM: s390: Simplify SIGP Set Arch handling" whereas 812de04661c4 already landed via upstream stable, hence only two are left and need to be cherry-picked: [Fix] * 67cf68b6a5ccac8bc7dfef0a220b59af4c83fd2c 67cf68b6a5cc "KVM: s390: Add a routine for setting userspace CPU state" * 8eeba194a32e0f50329354a696baaa2e3d9accc5 8eeba194a32e "KVM: s390: Simplify SIGP Set Arch handling" [Test Case] * Install an LPAR on IBM Z (z13+) or LinuxONE (Emperor / Rockhopper) with Ubuntu Server 20.04 using kernel standard kernel 5.4. * Setup this LPAR as QEMU/KVM host and a focal VM as guest. * The test itself is the following unit test: https://lore.kernel.org/r/20220303210425.1693486-1-far...@linux.ibm.com/ * The test and verification will be done by the IBM Z team. [Where problems could occur] * A broken patch could harm KVM ioctl on s390x or the (virtual) CPU state control in general. * The SIGP handing (on s390x) can become broken, which could lead to incorrect (virtual) CPU states. * In worst case KVM can become broken on s390x entirely. * The modified code is all s390x specific QEMU/KVM code, no common code is touched. [Other] * The two remaining patches are upstream since 5.16, the first one already landed in 5.4 via upstream stable bug LP#1959701 and in 5.13 via upstream stable bug LP#1960861. * The patches already landed in jammy (master-next) based on LP#1959735, hence only SRU to impish and focal is needed. * This patches got discussed here: https://lore.kernel.org/all/20211008203112.1979843-2-far...@linux.ibm.com/ * This not only fixes the SIGP processing, but is also important in terms of long term maintainability. __________ Description: KVM: SIGP RESTART is reporting a CPU state 'stopped' after SIGP RESTART was issued, while it should report a 'busy' condition until the CPU is really started. The patches to fix this have already been picked for jammy/master- next: 812de04661c4 "KVM: s390: Clarify SIGP orders versus STOP/RESTART" 435d17955519 "KVM: s390: Add a routine for setting userspace CPU state" 4563bcad46bf "KVM: s390: Simplify SIGP Set Arch handling" For Ubuntu 20.04 the focal/master-next already contains: d74b0d2d38d3 KVM: s390: Clarify SIGP orders versus STOP/RESTART so we additionally need the following two upstream commits in focal 67cf68b6a5cc KVM: s390: Add a routine for setting userspace CPU state 8eeba194a32e KVM: s390: Simplify SIGP Set Arch handling To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1962578/+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
