** Description changed:
+ SRU Justification
+
+ Impact: Since 4.15.0-15 some machines have been failing to boot due to
+ IO hangs. This is caused by patches applied for LP #1759723, which
+ assigned managed interrupt vectors and reply queues for all possible
+ CPUs, not just present CPUs. Some drivers were not prepared to cope with
+ this and end up selecting reply queues not mapped to an online CPU,
+ causing IO hangs during boot.
+
+ Fix: There are driver fixes available upstream, but there are 8-ish
+ patches in total and we're extremely close to release, so the safer bet
+ it to just revert the patches for LP #1759723. We can consider
+ reintroducing them with required fixes at a later time.
+
+ Regression Potential: This is obviously going to reintroduce the problem
+ the patches were intended to fix. These are less serious than the
+ problems which the patches introduced, and IBM has given their okay to
+ revert them as well.
+
+ Test Case: Verified to fix affected hardware on LP #1765232.
+
+ ---
+
For Ubuntu 18.04 amd64 server, I updated the kernel from 4.15.0-13 to
4.15.0-15. The system hangs at boot up now. Rolling back to the old
kernel everything works as expected. It appears to hang while trying to
enumerate an SD card device, which isn't even installed. I have tried
this on a Dell R620 and R820 and both have the exact same problem. I
even downloaded a new installer iso from the daily builds to reinstall
the OS and the installer hangs too now.
Support for Dell PowerEdge 12th gen servers appears to be broken with
kernel 4.15.0-15.
https://imgur.com/VT9zd0w
https://imgur.com/4BQPCXo
** Changed in: linux (Ubuntu Bionic)
Status: Confirmed => In Progress
** Changed in: linux (Ubuntu Bionic)
Assignee: (unassigned) => Seth Forshee (sforshee)
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/1765232
Title:
Kernel 4.15.0-15 breaks Dell PowerEdge 12th Gen servers
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1765232/+subscriptions
--
ubuntu-bugs mailing list
ubuntu-bugs@lists.ubuntu.com
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
