| 2018-08-14 20:13:44 |
Joseph Salisbury |
description |
I went to boot my computer today and it wouldn't boot.
I get an "Unable to handle kernel NULL pointer dereference" message during the boot process, and, a bit after that, a message from the kernel watchdog about CPU #0 being stuck. Then the boot process stops completely.
I was able to boot the system by telling Grub to load 4.15.0-22, which works perfectly fine, so there has been a regression.
I am running Ubuntu as a Xen dom0, if that matters. I haven't tried booting the offending kernel version without Xen.
I'm not sure where, if anywhere, these messages go on disk, for posting.
ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: linux-image-4.15.0-23-generic 4.15.0-23.25
ProcVersionSignature: Ubuntu 4.15.0-22.24-generic 4.15.17
Uname: Linux 4.15.0-22-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.20.9-0ubuntu7.1
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Sun Jun 17 10:12:58 2018
InstallationDate: Installed on 2017-08-06 (314 days ago)
InstallationMedia: Ubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412)
ProcEnviron:
TERM=xterm-256color
PATH=(custom, no user)
XDG_RUNTIME_DIR=<set>
LANG=en_US.UTF-8
SHELL=/bin/bash
SourcePackage: linux-signed
UpgradeStatus: Upgraded to bionic on 2018-05-29 (19 days ago) |
== SRU Justification ==
Mainline commit 1f50ddb4f418 introduced a regression. That commit added
speculative_store_bypass_ht_init() to the per-CPU initialization sequence.
However, speculative_store_bypass_ht_init() needs to be called on each CPU for
PV guests, as well.
The regresssion prevents systems from booting.
The patch to fix this regression has also been cc'd to upstream stable,
but it has not landed in Bionic as of yet.
== Fix ==
74899d92e666 ("x86/xen: Add call of speculative_store_bypass_ht_init() to PV paths")
== Regression Potential ==
Low. This patch fixes a current regressionThis patch has also been
submitted to upstream stable, so it has had additional upstream review.
== Test Case ==
A test kernel was built with this patch and tested by the original bug reporter.
The bug reporter states the test kernel resolved the bug.
I went to boot my computer today and it wouldn't boot.
I get an "Unable to handle kernel NULL pointer dereference" message during the boot process, and, a bit after that, a message from the kernel watchdog about CPU #0 being stuck. Then the boot process stops completely.
I was able to boot the system by telling Grub to load 4.15.0-22, which works perfectly fine, so there has been a regression.
I am running Ubuntu as a Xen dom0, if that matters. I haven't tried booting the offending kernel version without Xen.
I'm not sure where, if anywhere, these messages go on disk, for posting.
ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: linux-image-4.15.0-23-generic 4.15.0-23.25
ProcVersionSignature: Ubuntu 4.15.0-22.24-generic 4.15.17
Uname: Linux 4.15.0-22-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.20.9-0ubuntu7.1
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Sun Jun 17 10:12:58 2018
InstallationDate: Installed on 2017-08-06 (314 days ago)
InstallationMedia: Ubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412)
ProcEnviron:
TERM=xterm-256color
PATH=(custom, no user)
XDG_RUNTIME_DIR=<set>
LANG=en_US.UTF-8
SHELL=/bin/bash
SourcePackage: linux-signed
UpgradeStatus: Upgraded to bionic on 2018-05-29 (19 days ago) |
|
