severity 821225 normal retitle 821225 transparent huge pages cause disk/memory corruption inside VM, VM crashes on KVM on AMD CPUs thanks
On Sat, Apr 16, 2016 at 09:45:52PM +0200, Marc Haber wrote: > I have a desktop PC running with an AMD Phenom II X6 1090T processor, > cpu family 16, model 10. This is as far as I know not subject to the > recent AMD microcode issues, but the amd64-microcode package is > installed nevertheless. > > The host is running a few KVM VMs, also Debian. As soon as the host > runs a kernel of 4.5.0 or later, VMs fail through disk-intensive > operations, such as running aide --update multiple times in a row. > This is independent of the kernel version runing in the guest. > > Failures can manifest themselves in processes in the guest > segfaulting, the guest detecting a journal abort of its ext4 > filesystems and remounting the filesystem r/o or the guest stopping > dead in its tracks. Neither the logs of the guest nor of the host show > anything more conclusive. The system can run for up to six hours > before the VM begins to show the errativ behavior, but usually the > issue surfaces in the first ten minutes of the system running. A workaround is disabling transparent huge pages at runtime. With this setting, all VMs are fine again. Greetings Marc -- ----------------------------------------------------------------------------- Marc Haber | "I don't trust Computers. They | Mailadresse im Header Leimen, Germany | lose things." Winona Ryder | Fon: *49 6224 1600402 Nordisch by Nature | How to make an American Quilt | Fax: *49 6224 1600421
