** Description changed:

+ == SRU Justification BIONIC HWE ==
+ 
  Installed Bionic 18.04.2 i386 Desktop (using xubuntu) on a Lenovo x220i
  and upgraded to proposed. The 5.0.0.22 kernel crashes in various ways
  with video corruption being a main visible featured.
  
  The CPU is a  i3-2350M CPU, a 64 bit capable CPU, being booted with EUFI
  firmware disabled, so using traditional BIOS.
  
  1. Crashes can be just complete hangs, no ability to switch virtual console
  2. Crashes may just result in screen turning off, no video and hang and/or 
reboot
  3. Crashes sometimes allow virtual console. Can see watchdog hang checks 
appearing on 1 or more CPUs.
  
  Tried the i386 https://kernel.ubuntu.com/~kernel-ppa/mainline/?C=N;O=D
  kernels:
  
  https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.0.21/ - same issue
  https://kernel.ubuntu.com/~kernel-ppa/mainline/v4.20.17/ - same issue
  https://kernel.ubuntu.com/~kernel-ppa/mainline/v4.19.61/ - OK
  
  We therefore can conclude:
  
  1. Issue appears between 4.19.61 and 4.20.17
  2. Issue is in upstream kernel
  3. Issue not a kernel patch per-se (e.g. security fix, ubuntu sauce patch, 
etc)
  
  I repeated this with a VM installation and I don't see the issue, so
  this probably is a hardware (or firmware?) specific issue.
+ 
+ == Fix ==
+ 
+ Backport wiggle of upstream fix
+ 
+ 3f8fd02b1bf1d7ba964485a56f2f4b53ae88c167 ("mm/vmalloc: Sync unmappings
+ in __purge_vmap_area_lazy()")
+ 
+ == Test ==
+ 
+ Without the fix, i386 xubuntu on various Lenovo platforms crash during
+ early boot with random video corruption, hangs,lockups or even reboots.
+ 
+ With the fix, it boots fine.
+ 
+ == Regression Potential ==
+ 
+ Higher than normal as this touches the mm sync and the fix has only just
+ hit upstream so it has not much of a soak test.  Testing with this shows
+ it fixes a kitten killer breakage, so I think the risk vs benefit is
+ worth considering

** Description changed:

- == SRU Justification BIONIC HWE ==
+ == SRU Justification BIONIC HWE, DISCO ==
  
  Installed Bionic 18.04.2 i386 Desktop (using xubuntu) on a Lenovo x220i
  and upgraded to proposed. The 5.0.0.22 kernel crashes in various ways
  with video corruption being a main visible featured.
  
  The CPU is a  i3-2350M CPU, a 64 bit capable CPU, being booted with EUFI
  firmware disabled, so using traditional BIOS.
  
  1. Crashes can be just complete hangs, no ability to switch virtual console
  2. Crashes may just result in screen turning off, no video and hang and/or 
reboot
  3. Crashes sometimes allow virtual console. Can see watchdog hang checks 
appearing on 1 or more CPUs.
  
  Tried the i386 https://kernel.ubuntu.com/~kernel-ppa/mainline/?C=N;O=D
  kernels:
  
  https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.0.21/ - same issue
  https://kernel.ubuntu.com/~kernel-ppa/mainline/v4.20.17/ - same issue
  https://kernel.ubuntu.com/~kernel-ppa/mainline/v4.19.61/ - OK
  
  We therefore can conclude:
  
  1. Issue appears between 4.19.61 and 4.20.17
  2. Issue is in upstream kernel
  3. Issue not a kernel patch per-se (e.g. security fix, ubuntu sauce patch, 
etc)
  
  I repeated this with a VM installation and I don't see the issue, so
  this probably is a hardware (or firmware?) specific issue.
  
  == Fix ==
  
  Backport wiggle of upstream fix
  
  3f8fd02b1bf1d7ba964485a56f2f4b53ae88c167 ("mm/vmalloc: Sync unmappings
  in __purge_vmap_area_lazy()")
  
  == Test ==
  
  Without the fix, i386 xubuntu on various Lenovo platforms crash during
  early boot with random video corruption, hangs,lockups or even reboots.
  
  With the fix, it boots fine.
  
  == Regression Potential ==
  
  Higher than normal as this touches the mm sync and the fix has only just
  hit upstream so it has not much of a soak test.  Testing with this shows
  it fixes a kitten killer breakage, so I think the risk vs benefit is
  worth considering

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1838115

Title:
  linux hwe i386 kernel 5.0.0-21.22~18.04.1 crashes on Lenovo x220

Status in linux package in Ubuntu:
  In Progress

Bug description:
  == SRU Justification BIONIC HWE, DISCO ==

  Installed Bionic 18.04.2 i386 Desktop (using xubuntu) on a Lenovo
  x220i and upgraded to proposed. The 5.0.0.22 kernel crashes in various
  ways with video corruption being a main visible featured.

  The CPU is a  i3-2350M CPU, a 64 bit capable CPU, being booted with
  EUFI firmware disabled, so using traditional BIOS.

  1. Crashes can be just complete hangs, no ability to switch virtual console
  2. Crashes may just result in screen turning off, no video and hang and/or 
reboot
  3. Crashes sometimes allow virtual console. Can see watchdog hang checks 
appearing on 1 or more CPUs.

  Tried the i386 https://kernel.ubuntu.com/~kernel-ppa/mainline/?C=N;O=D
  kernels:

  https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.0.21/ - same issue
  https://kernel.ubuntu.com/~kernel-ppa/mainline/v4.20.17/ - same issue
  https://kernel.ubuntu.com/~kernel-ppa/mainline/v4.19.61/ - OK

  We therefore can conclude:

  1. Issue appears between 4.19.61 and 4.20.17
  2. Issue is in upstream kernel
  3. Issue not a kernel patch per-se (e.g. security fix, ubuntu sauce patch, 
etc)

  I repeated this with a VM installation and I don't see the issue, so
  this probably is a hardware (or firmware?) specific issue.

  == Fix ==

  Backport wiggle of upstream fix

  3f8fd02b1bf1d7ba964485a56f2f4b53ae88c167 ("mm/vmalloc: Sync unmappings
  in __purge_vmap_area_lazy()")

  == Test ==

  Without the fix, i386 xubuntu on various Lenovo platforms crash during
  early boot with random video corruption, hangs,lockups or even
  reboots.

  With the fix, it boots fine.

  == Regression Potential ==

  Higher than normal as this touches the mm sync and the fix has only
  just hit upstream so it has not much of a soak test.  Testing with
  this shows it fixes a kitten killer breakage, so I think the risk vs
  benefit is worth considering

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1838115/+subscriptions

-- 
Mailing list: https://launchpad.net/~kernel-packages
Post to     : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help   : https://help.launchpad.net/ListHelp

Reply via email to