We just hit this bug again, so it is clearly not fixed yet. Attaching
another syslog. It seems to be triggered by a combination of echo 3 >
/proc/sys/vm/drop_caches and destroying cgroups, but I have yet to find
a reliable way of reproducing it.
** Attachment added: "syslog.txt"
I have tested with v4.9-rc2, and been unable to reproduce the bug there.
However, I haven't found any reliable way to reproduce the bug on the
current kernel, so I am not completely certain that the bug is not
present in v4.9-rc2.
For now, I have tagged the bug `kernel-fixed-upstream`, if this is
Would it be possible for you to test the latest upstream kernel? Refer
to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest
v4.9 kernel[0].
If this bug is fixed in the mainline kernel, please add the following
tag 'kernel-fixed-upstream'.
If the mainline kernel does not fix
