Problem with latest kernel?
Problem with latest kernel?
I have a couple of Virtual private servers, one running under Xen and the other KVM.
After installing the latest updates (including the latest kernel), neither boots. The virtual serial consoles provided by the VM services show nothing.
After installing the latest updates (including the latest kernel), neither boots. The virtual serial consoles provided by the VM services show nothing.
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- Posts: 5
- Joined: 2015/10/21 12:29:31
Re: Problem with latest kernel?
I also have a number of Centos 6.9 virtual machines (running under Xenserver 7.1) and after updating these fail to boot as well. I have reinstalled grub and they still fail. They reach the point where they would boot and then almost immediately shut down.
Listening in on chat in the CentOS-virt channel on freenode implies that the problem could be down to an incompatibility with VMs running in PV (paravirtualised) mode. Apparently, converting them to HVM (hardware assisted virtualisation) may work. I am checking this out at the moment and will post more if I find anything.
For the time being, I have re-enabled the original kernel, which is probably less than ideal given the latest vulnerabilities.
Listening in on chat in the CentOS-virt channel on freenode implies that the problem could be down to an incompatibility with VMs running in PV (paravirtualised) mode. Apparently, converting them to HVM (hardware assisted virtualisation) may work. I am checking this out at the moment and will post more if I find anything.
For the time being, I have re-enabled the original kernel, which is probably less than ideal given the latest vulnerabilities.
Re: Problem with latest kernel?
I can confirm the issue. All Centos 6.9 with latest kernel running under xenserver 7.x are affected. DO NOT UPDATE !
Let's wait for a fix, hopefully soon
Let's wait for a fix, hopefully soon
Re: Problem with latest kernel?
This issue is apparently something to do with the new code for the "meltdown" vulnerability and is currently failing on both el6 and el7 latest kernels.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke
Re: Problem with latest kernel?
This is being tracked in https://bugs.centos.org/view.php?id=14336
Re: Problem with latest kernel?
Don't these kernel updates get any testing? I realize that CentOS may have very limited resources for testing, but doesn't Red Hat test these updates?
This isn't some subtle bug. This is a catastrophic bug.
This isn't some subtle bug. This is a catastrophic bug.
Re: Problem with latest kernel?
Bug is already under investigation by Karanbir Singh. Centos Project Leader.
Let's keep finger crossed
Let's keep finger crossed
Re: Problem with latest kernel?
I don't think RH care much about xen. The initial 7.4 kernel fails to boot as a xen guest and they've not scheduled a fix until 7.5, ETA unknown.
Does the new 6.9 kernel work under xen if you append pti=off (or maybe nopti) to the kernel command line?
The problem with kvm is most likely different as I have successfully installed the new 6.9 kernel on both kvm hosts and guests without problem (other than the expected eating of cpu).
Does the new 6.9 kernel work under xen if you append pti=off (or maybe nopti) to the kernel command line?
The problem with kvm is most likely different as I have successfully installed the new 6.9 kernel on both kvm hosts and guests without problem (other than the expected eating of cpu).
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke
Re: Problem with latest kernel?
I haven't the possibility of trying the "nopti" option at boot time right now, sorry.
Re: Problem with latest kernel?
Having the same issue on AWS using standard CentOS 6.9 PV minimal image. Looks like adding pti=off OR nopti to the 18.7 (Intel patch) kernel command line does not result in successful boot after yum update.