Re: x86 hibernate, resume with different kernel version

On Thu, Jun 16, 2016 at 02:11:48PM +0200, Rafael J. Wysocki wrote:

On Thu, Jun 16, 2016 at 12:03 PM, Johannes Stezenbach [off-list ref] wrote:

quoted

it's not important for me but I hibernated kernel v4.5.7
and inadvertantly resumed using v4.6.2, and ISTR this
should work (confirmed by looking into git where I found
commit cc456c4e7cac3837a86aaa7ca3cb9f488d44d196).

My swap is an LVM volume inside dm-crypt, on boot the kernel read
the resume image but then immediately reset and invalidated it.
I'm using Debian sid, the initrd calls /bin/resume from
klibc-utils package.

So, should this still work?  I couldn't find any
information about it.

It should in theory, but may not in fact due to bugs discovered
recently.  This patch should help:
https://patchwork.kernel.org/patch/9172981/ (it has to be applied to
both the image and boot kernels).

I applied it to both the v4.5.7 and v4.6.2 kernels, booted
v4.5.7, hibernated, booted v4.6.2 to resume: still resets.

Let me know if you have something else to test.
BTW, the machine has a serial port in case you'd
like me to capture logs, but then please be specific
about the how and what so I don't waste my time.


Thanks,
Johannes