Sorry, it's not convenient for me to test Ubuntu at the moment.

I abuse the above instructions to assert that this bug is confirmed,
citing the URLs provided.  (1: The patch+description linked for kernel
4.17, 2: the lack of fix evidenced in the link for kernel 4.15.0-24.26).

I appeal to authority based on me being the author of the fix, which was
merged to the Linux kernel :).

Furthermore, I do so on behalf of two Ubuntu users active on Ubuntu bug
linked above.[1]  In the first instance, I analysed the crash dump and
explained the very distinct signature which it shows, indicating this
bug.  The second user confirmed that they suffered this bug and used a
very specific workaround to avoid it.

[1] https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1760450/

(The Ubuntu bug is marked as affecting 7 people overall.  I am certain
this is an understatement.  I mentioned in my comment in the bug, how
the nature of the crashes made them hard for users to identify.  One
part is the same as the experience we had in Fedora. Automatically
reported crashes were not reliably detected as duplicates, because the
fatal SIGBUS signal can happen at a number of different points).

** Changed in: linux (Ubuntu)
       Status: Incomplete => Confirmed

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https://bugs.launchpad.net/bugs/1776887

Title:
  Critical upstream bugfix missing in Ubuntu 18.04 - frequent Xorg crash
  after suspend

Status in linux package in Ubuntu:
  Confirmed

Bug description:
  This upstream bug has been confirmed to affect Ubuntu users[1].  As
  per the fix commit (below), the most frequent symptom is a crash of
  Xorg/Xwayland, i.e. killing the entire GUI, when a laptop is woken
  from system sleep.  Frequency of the bug is described as once every
  few days[2].

  [1] E.g. this user confirms the bug & very specific workaround: 
https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1760450/comments/11
  [2] E.g. this log of crashes: 
https://bugzilla.redhat.com/show_bug.cgi?id=1553979#c23

  This is a bug in blk-core.c.  It is not specific to any one hardware
  driver.  Technically the suspend bug is triggered by the SCSI core -
  which is used by *all SATA devices*.

  The commit also includes a test which quickly and reliably proves the
  existence of a horrifying bug.

  I guess you might avoid this bug only if you have root on NVMe.  The
  other way to not hit the Xorg crash is if you don't use all your RAM,
  so there's no pressure that leads to cold pages of Xorg being swapped.
  Also, you won't reproduce the Xorg crash if you suspend+resume
  immediately.  (This frustrated my tests at one point, it only
  triggered after left the system suspended over lunch :).

  
  Fix: "block: do not use interruptible wait anywhere"

  in kernel 4.17:
  
https://github.com/torvalds/linux/commit/1dc3039bc87ae7d19a990c3ee71cfd8a9068f428

  in kernel 4.16.8:
  https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-
  stable.git/commit/?h=linux-4.16.y&id=7859056bc73dea2c3714b00c83b253d4c22bf7b6

  lack of fix in 4.15.0-24.26 (ubuntu 18.04): https://git.launchpad.net
  /~ubuntu-kernel/ubuntu/+source/linux/+git/bionic/tree/block/blk-
  core.c?id=Ubuntu-4.15.0-24.26#n856

  I.e., this bug is still present in Ubuntu source package
  linux-4.15.0-24.26 (and 4.15.0-23.25).  I attach hardware details
  (lspci-vnvn.log) of a system where this bug is known to happen.

  Regards
  Alan

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