<![CDATA[[RHEL kernel bug] XCP vm fails to boot after newest kernel applied.]]>We have a ticket from some users who were unable to boot their Xen vms after updating to the newest Red Hat kernel (4.18.0-553.50.1.el8_10.x86_64) That same kernel seems to work ok on VMware. We've seen references to it in the wild https://forums.almalinux.org/t/kernel-panic-4-18-0-553-50-1-el8-10-x86-64-on-xenserver-8-4/5754
We're telling our users to hold off on that patch until we know more.
The xen security advisory is from back in December but looks like the fix implementation has broken something. https://xenbits.xen.org/xsa/advisory-466.html
Any workarounds known?

]]>https://xcp-ng.org/forum/topic/10752/rhel-kernel-bug-xcp-vm-fails-to-boot-after-newest-kernel-applied.RSS for NodeTue, 09 Jun 2026 17:30:18 GMTThu, 17 Apr 2025 14:48:06 GMT60<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Sat, 03 May 2025 17:52:49 GMT]]>Great news πŸ™‚ Closing this as fixed. Thanks everyone for your feedback!

]]>https://xcp-ng.org/forum/post/92581https://xcp-ng.org/forum/post/92581Sat, 03 May 2025 17:52:49 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Fri, 02 May 2025 18:12:11 GMT]]>.51 for Rocky showed up today. Running my first test. and from .22.

Seems successful!

]]>https://xcp-ng.org/forum/post/92569https://xcp-ng.org/forum/post/92569Fri, 02 May 2025 18:12:11 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Fri, 02 May 2025 12:29:10 GMT]]>I updated my Redhat 8 instances to the .51 kernel and it's back to working.

The kernel version 4.18.0-553.51.1.el8_10.x86_64 for Red Hat Enterprise Linux 8 was released on April 30, 2025, as part of the bug fix advisory RHBA-2025:4337. ​

This update addresses various issues and includes enhancements to improve system stability and performance. For detailed information about the fixes and improvements in this release, you can refer to the official Red Hat advisory.

]]>https://xcp-ng.org/forum/post/92564https://xcp-ng.org/forum/post/92564Fri, 02 May 2025 12:29:10 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Thu, 01 May 2025 18:24:15 GMT]]>@bberndt

Alma must have dropped everything to push this out. I wonder what Oracle is doing, guessing they were hit by this too. I'd guess Rocky has this out pretty fast, they know it is important.

]]>https://xcp-ng.org/forum/post/92542https://xcp-ng.org/forum/post/92542Thu, 01 May 2025 18:24:15 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Thu, 01 May 2025 18:12:32 GMT]]>@Greg_E said in XCP vm fails to boot after newest kernel applied.:

@bberndt

This may sound stupid, but here goes...

Does Rocky need to update to .50 before it can update to .51?

I'd guess no, but I've been away from RHEL based stuff since the IBM rug pull. Only coming back because I may need it in the future as I jockey around trying to improve my paycheck.

https://bugs.rockylinux.org/view.php?id=9307
so, prolly soon-ish.

]]>https://xcp-ng.org/forum/post/92540https://xcp-ng.org/forum/post/92540Thu, 01 May 2025 18:12:32 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Thu, 01 May 2025 18:03:41 GMT]]>@bberndt

This may sound stupid, but here goes...

Does Rocky need to update to .50 before it can update to .51?

I'd guess no, but I've been away from RHEL based stuff since the IBM rug pull. Only coming back because I may need it in the future as I jockey around trying to improve my paycheck.

]]>https://xcp-ng.org/forum/post/92539https://xcp-ng.org/forum/post/92539Thu, 01 May 2025 18:03:41 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Thu, 01 May 2025 17:59:54 GMT]]>@Greg_E said in XCP vm fails to boot after newest kernel applied.:

@olivierlambert

I just updated an Alma 8 and it has the .51 kernel now.

Tried one of my Rocky's and still .50. I wonder where we can see the status of downstream fixes like that? anyone know? thanks.

]]>https://xcp-ng.org/forum/post/92538https://xcp-ng.org/forum/post/92538Thu, 01 May 2025 17:59:54 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Thu, 01 May 2025 17:53:02 GMT]]>@olivierlambert

I just updated an Alma 8 and it has the .51 kernel now.

]]>https://xcp-ng.org/forum/post/92537https://xcp-ng.org/forum/post/92537Thu, 01 May 2025 17:53:02 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Wed, 30 Apr 2025 19:43:52 GMT]]>It's now available, yes πŸ™‚ After update, reboot will work

edit: ha answered for RH, Alma and Rocky will follow soon I suppose

]]>https://xcp-ng.org/forum/post/92496https://xcp-ng.org/forum/post/92496Wed, 30 Apr 2025 19:43:52 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Wed, 30 Apr 2025 17:56:58 GMT]]>@Greg_E
I made a free account.
Resolution
The issue has been resolved with the errata: RHBA-2025:4337. Hence, update the kernel to kernel-4.18.0-553.51.1.el8_10 to fix the issue.

id assume it arrives soon? I as well, haven't seen it yet.

]]>https://xcp-ng.org/forum/post/92490https://xcp-ng.org/forum/post/92490Wed, 30 Apr 2025 17:56:58 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Wed, 30 Apr 2025 14:48:00 GMT]]>@phil

Sad that even this documentation is locked behind a Redhat account, I can only read part of the problem description. Not going to make an account because it really doesn't affect me right now.

]]>https://xcp-ng.org/forum/post/92475https://xcp-ng.org/forum/post/92475Wed, 30 Apr 2025 14:48:00 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Wed, 30 Apr 2025 14:42:36 GMT]]>According to https://access.redhat.com/solutions/7116307 the bug is solved, but I don't get newer Kernels on Rocky yet.

]]>https://xcp-ng.org/forum/post/92474https://xcp-ng.org/forum/post/92474Wed, 30 Apr 2025 14:42:36 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Mon, 28 Apr 2025 08:15:33 GMT]]>@Greg_E according to the Knowledge base of Redhawks it is den Witz Intel CPUs. So you AMD isnβ€˜t affected

]]>https://xcp-ng.org/forum/post/92375https://xcp-ng.org/forum/post/92375Mon, 28 Apr 2025 08:15:33 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Mon, 28 Apr 2025 00:28:28 GMT]]>@Greg_E Maybe it only affects Intel? That would be a new wrinkle. Perhaps other AMD users can confirm if the latest AlmaLinux 8 kernel runs fine on their AMD XCP-ng 8.3 hosts? Just read the above referenced RedHat bug report here: https://access.redhat.com/solutions/7116307 Sure enough, it says Xen + Intel in problem description. Check it out.

]]>https://xcp-ng.org/forum/post/92366https://xcp-ng.org/forum/post/92366Mon, 28 Apr 2025 00:28:28 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Sun, 27 Apr 2025 22:15:29 GMT]]>@XCP-ng-JustGreat

I'm running the same guest tools.

Could it be a processor related issue? I'm running AMD v1756b in my lab, haven't had time to try in production that is Intel Silver.

]]>https://xcp-ng.org/forum/post/92364https://xcp-ng.org/forum/post/92364Sun, 27 Apr 2025 22:15:29 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Sun, 27 Apr 2025 13:25:28 GMT]]>@Greg_E Wondering what might be the difference? I am using the XenServer Linux tools version 8.4.0-1 and BIOS boot firmware.

]]>https://xcp-ng.org/forum/post/92360https://xcp-ng.org/forum/post/92360Sun, 27 Apr 2025 13:25:28 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Sun, 27 Apr 2025 03:11:58 GMT]]>@XCP-ng-JustGreat

Strange that my fresh Alma 8.10 is still working after updates, makes me think k there is more to this than just the kernel.

]]>https://xcp-ng.org/forum/post/92352https://xcp-ng.org/forum/post/92352Sun, 27 Apr 2025 03:11:58 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Sun, 27 Apr 2025 01:43:24 GMT]]>This is just a "me too" reply to indicate that I am also experiencing the boot failure immediately after upgrading AlmaLinux 8.10 to the latest kernel 4.18.0-553.50.1. Hopefully, the kernel fix will get integrated soon into the affected and popular RedHat 8 derivatives so that Alma and Rocky 8 et al. can continue to run on our favorite hypervisor. This is a bad one.

]]>https://xcp-ng.org/forum/post/92350https://xcp-ng.org/forum/post/92350Sun, 27 Apr 2025 01:43:24 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Fri, 25 Apr 2025 07:29:16 GMT]]>@bberndt you Rocky/Alma 9 will be fine since it's a bug in the kernel for 8 only.

]]>https://xcp-ng.org/forum/post/92286https://xcp-ng.org/forum/post/92286Fri, 25 Apr 2025 07:29:16 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Fri, 25 Apr 2025 07:30:08 GMT]]>@Greg_E They are all running for a while but none where upgrades from RHEL 7 to RHEL 8. I don't do LEAPPs that gives me more often errors than it works. What I did though on one is replacing the System VDI with a newer one, but that was Alma 8 to Alma 9 and that one has no issues.

]]>https://xcp-ng.org/forum/post/92285https://xcp-ng.org/forum/post/92285Fri, 25 Apr 2025 07:30:08 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Thu, 24 Apr 2025 16:34:01 GMT]]>@Greg_E said in XCP vm fails to boot after newest kernel applied.:

@bberndt

Ok, that might explain the difference.

Would a LEAPP from Rocky 8 up to Alma 9 be possible and solve the issue?

I did a (not LEAPP, but a migration script from Alama) from Rocky 8 to Alma 8, and it died. None of my Rocky 9's have had a problem so far, and of course end up with a completely different kernel.

]]>https://xcp-ng.org/forum/post/92254https://xcp-ng.org/forum/post/92254Thu, 24 Apr 2025 16:34:01 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Thu, 24 Apr 2025 15:49:43 GMT]]>FYI, there's a patch submitted to linux-stable (6.6 and earlier) but not yet in a stable release:
https://lore.kernel.org/stable/20250411160833.12944-1-jason.andryuk@amd.com/

I guess we'll have to wait until this is picked up by Linux, then Red Hat will have to pick that as well.

]]>https://xcp-ng.org/forum/post/92249https://xcp-ng.org/forum/post/92249Thu, 24 Apr 2025 15:49:43 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Thu, 24 Apr 2025 13:35:30 GMT]]>@bufanda

How many of these that are failing have been upgraded from a previous version? Could it be something left over from EL7 or early EL8?

My Alma 8.10 base install is still running fine, did a yum update to apply a few more things and reboot and still working with the same kernel version above. But again, this was a clean fresh install, not something that's been running for a while.

]]>https://xcp-ng.org/forum/post/92221https://xcp-ng.org/forum/post/92221Thu, 24 Apr 2025 13:35:30 GMT<![CDATA[Reply to [RHEL kernel bug] XCP vm fails to boot after newest kernel applied. on Thu, 24 Apr 2025 06:52:20 GMT]]>@Greg_E said in XCP vm fails to boot after newest kernel applied.:

@bberndt
I just installed a fresh Alma 8, did yum update to see what would happen, and it's still working. Gave out the same kernel as above.

Alma8.png

This was installed UEFI on XCP-ng 8.3 which was a fresh install a few days ago from a nightly (near release?) ISO. It was installed to an NFS share, 2 cores and 4GB with an Intel i1000 interface. Xenserver tools 8.4.0-1 installed.

There are no extra packages installed yet, could this be a package conflict.

Anything else I can check to see why mine works and others are failing?

Hmm....I did the same and that VM died just like any other with the broken kernel.
Although I used the Cloud Image so not completly new install from scratch.
Maybe I'll check building a new cloud image what will happen then.

]]>https://xcp-ng.org/forum/post/92184https://xcp-ng.org/forum/post/92184Thu, 24 Apr 2025 06:52:20 GMT