Kernel update: Virtuozzo ReadyKernel patch 83.0 for all supported Virtuozzo 7.0 and Virtuozzo Infrastructure Platform kernels¶
Issue date: 2019-07-12
Applies to: Virtuozzo 7.0, Virtuozzo Infrastructure Platform 2.5, Virtuozzo Infrastructure Platform 3.0
Virtuozzo Advisory ID: VZA-2019-057
1. Overview¶
The cumulative Virtuozzo ReadyKernel patch was updated with stability fixes. The patch applies to all supported kernels of Virtuozzo 7.0 and Virtuozzo Infrastructure Platform.
2. Bug Fixes¶
[3.10.0-862.9.1.vz7.63.3 to 3.10.0-957.12.2.vz7.86.2] It was found that the in-kernel implementation of Virtuozzo Storage client stored latency values in milliseconds rather than in microseconds, resulting in bogus statistics data. (PSBM-94882)
[3.10.0-957.10.1.vz7.85.17 and 3.10.0-957.12.2.vz7.86.2] It was discovered that a race could happen between removal of memcg and workingset_refault() running in parallel. This could result in a kernel crash in memcg_inc_ws_activate(). (PSBM-95700)
[All but 3.10.0-957.12.2.vz7.96.17] It was discovered that a node with dozens of CPU cores, lots of RAM and many VMs running could get into a situation when almost all CPU cores were busy in mmu_shrink_scan(). This could happen because memory shrinking was done under kvm_lock spinlock and only for one VM at a time. All CPU cores but one just waited for kvm_lock in such cases, while the last one was busy with the actual memory shrinking for a VM. (PSBM-95077)
mem_cgroup_reparent_charges() could get stuck while holding cgroup_mutex and make the whole system hang. (VSTOR-24241)
3. Installing the Update¶
Download, install, and immediately apply the patch to the current kernel by running ‘readykernel update’.
4. References¶
The JSON file with the list of new and updated packages is available at https://docs.virtuozzo.com/vza/VZA-2019-057.json.