Public bug reported: Microsoft has identified a multiple-NIC-deadlock issue on Hyper-V VMs. This bug is fixed by the following commit, which is in mainline as of v4.20-rc6: 37c2578c0c40 ("Drivers: hv: vmbus: Offload the handling of channels to two workqueues")
A second commit is also needed to prevent a deadlock with single NIC VMs. This commit is in mainline as of 4.19-rc3: e04e7a7bbd4b ("hv_netvsc: Fix a deadlock by getting rtnl lock earlier in netvsc_probe()") linux-azure, Bionic, Cosmic and Disco(4.15+ kernels) require the following two dependent commits: 4.19-rc1 - 50229128727f ("Drivers: hv: vmbus: Fix the offer_in_progress in vmbus_process_offer()") 4.19-rc4 - 6712cc9c2211 ("vmbus: don't return values for uninitalized channels") Xenial(4.14 and older kernels) require the following four dependent commits: 4.15-rc1 - c2e5df616e1a ("vmbus: add per-channel sysfs info") 4.15-rc6 - 869b5567e12f ("vmbus: unregister device_obj->channels_kset") 4.19-rc1 - 50229128727f ("Drivers: hv: vmbus: Fix the offer_in_progress in vmbus_process_offer()") 4.19-rc4 - 6712cc9c2211 ("vmbus: don't return values for uninitalized channels") ** Affects: linux (Ubuntu) Importance: Medium Assignee: Joseph Salisbury (jsalisbury) Status: Triaged ** Affects: linux (Ubuntu Xenial) Importance: Medium Assignee: Joseph Salisbury (jsalisbury) Status: Triaged ** Affects: linux (Ubuntu Bionic) Importance: Medium Assignee: Joseph Salisbury (jsalisbury) Status: Triaged ** Affects: linux (Ubuntu Cosmic) Importance: Medium Assignee: Joseph Salisbury (jsalisbury) Status: Triaged ** Affects: linux (Ubuntu Disco) Importance: Medium Assignee: Joseph Salisbury (jsalisbury) Status: Triaged ** Tags: bionic cosmic disco kernel-hyper-v xenial ** Changed in: linux (Ubuntu) Importance: Undecided => Medium ** Changed in: linux (Ubuntu) Assignee: (unassigned) => Joseph Salisbury (jsalisbury) ** Changed in: linux (Ubuntu) Status: New => Triaged ** Also affects: linux (Ubuntu Cosmic) Importance: Undecided Status: New ** Also affects: linux (Ubuntu Disco) Importance: Medium Assignee: Joseph Salisbury (jsalisbury) Status: Triaged ** Also affects: linux (Ubuntu Xenial) Importance: Undecided Status: New ** Also affects: linux (Ubuntu Bionic) Importance: Undecided Status: New ** Changed in: linux (Ubuntu Cosmic) Status: New => Triaged ** Changed in: linux (Ubuntu Bionic) Status: New => Triaged ** Changed in: linux (Ubuntu Xenial) Status: New => Triaged ** Changed in: linux (Ubuntu Cosmic) Importance: Undecided => Medium ** Changed in: linux (Ubuntu Bionic) Importance: Undecided => Medium ** Changed in: linux (Ubuntu Xenial) Importance: Undecided => Medium ** Changed in: linux (Ubuntu Cosmic) Assignee: (unassigned) => Joseph Salisbury (jsalisbury) ** Changed in: linux (Ubuntu Bionic) Assignee: (unassigned) => Joseph Salisbury (jsalisbury) ** Changed in: linux (Ubuntu Xenial) Assignee: (unassigned) => Joseph Salisbury (jsalisbury) -- 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/1807757 Title: Drivers: hv: vmbus: Offload the handling of channels to two workqueues Status in linux package in Ubuntu: Triaged Status in linux source package in Xenial: Triaged Status in linux source package in Bionic: Triaged Status in linux source package in Cosmic: Triaged Status in linux source package in Disco: Triaged Bug description: Microsoft has identified a multiple-NIC-deadlock issue on Hyper-V VMs. This bug is fixed by the following commit, which is in mainline as of v4.20-rc6: 37c2578c0c40 ("Drivers: hv: vmbus: Offload the handling of channels to two workqueues") A second commit is also needed to prevent a deadlock with single NIC VMs. This commit is in mainline as of 4.19-rc3: e04e7a7bbd4b ("hv_netvsc: Fix a deadlock by getting rtnl lock earlier in netvsc_probe()") linux-azure, Bionic, Cosmic and Disco(4.15+ kernels) require the following two dependent commits: 4.19-rc1 - 50229128727f ("Drivers: hv: vmbus: Fix the offer_in_progress in vmbus_process_offer()") 4.19-rc4 - 6712cc9c2211 ("vmbus: don't return values for uninitalized channels") Xenial(4.14 and older kernels) require the following four dependent commits: 4.15-rc1 - c2e5df616e1a ("vmbus: add per-channel sysfs info") 4.15-rc6 - 869b5567e12f ("vmbus: unregister device_obj->channels_kset") 4.19-rc1 - 50229128727f ("Drivers: hv: vmbus: Fix the offer_in_progress in vmbus_process_offer()") 4.19-rc4 - 6712cc9c2211 ("vmbus: don't return values for uninitalized channels") To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1807757/+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