The following upstream patch: >From 25fb213d873977290caf374234df496ad158ec1e Mon Sep 17 00:00:00 2001 From: Rik van Riel <[email protected]> Date: Mon, 21 Mar 2016 15:13:27 +0100 Subject: [PATCH 2/2] kvm, rt: change async pagefault code locking for PREEMPT_RT
The async pagefault wake code can run from the idle task in exception context, so everything here needs to be made non-preemptible. Conversion to a simple wait queue and raw spinlock does the trick. Signed-off-by: Rik van Riel <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]> Fixes the issue by not letting async pagefault code to be preempted due to waitqueues. Backport for Trusty needs: >From 25fb213d873977290caf374234df496ad158ec1e Mon Sep 17 00:00:00 2001 From: Rik van Riel <[email protected]> Date: Mon, 21 Mar 2016 15:13:27 +0100 Subject: [PATCH 2/2] kvm, rt: change async pagefault code locking for PREEMPT_RT >From 6b9cf536987c69825f91af9478109aa7bcbebc94 Mon Sep 17 00:00:00 2001 From: "Peter Zijlstra (Intel)" <[email protected]> Date: Fri, 19 Feb 2016 09:46:37 +0100 Subject: [PATCH 1/2] wait.[ch]: Introduce the simple waitqueue (swait) implementation If adding simple waitqueue interface to Trusty is not acceptable as SRU I'll have to come up with something else. I'm sure that problem goes away when using these 2 patches. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1596941 Title: KVM deadlock on KVM guest migration with latest QEMU (mitaka) from Xenial (or Mitaka Ubuntu Cloud Archive) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1596941/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
