SUSE-SU-2020:0388-1 Security update for xen

This update for xen fixes the following issues: - CVE-2018-12207: Fixed a race condition where untrusted virtual machines could have been using the Instruction Fetch Unit of the Intel CPU to cause a Machine Exception during Page Size Change, causing the CPU core to be non-functional bsc1155945...

missing preemption in x86 PV page table unvalidation

ISSUE DESCRIPTION XSA-273 changes required, among other things, making any PTE updates restartable. The changes making PTE updates restartable assumed that L2 pagetables would always be promoted preemptibly; but this turns out not to be the case when using the 'linear pagetable' feature; the resu...