RE: Odd hang on suspend and shutdown

On my Sony VAIO Pro 11 laptop, commit c93b76b34b4d ("mei: bus: report
also uuid in module alias") seems to cause problems at suspend and
shutdown.

In particular, reverting just the oneliner to drivers/nfc/pn544/mei.c
seems to fix things for me. The bisection was a pain, because it took
me forever to realize that it was that one-liner that caused it: I had
initially undone that one line simply because it didn't compile with
it in place (complaints about MEI_NFC_UUID not being constant). So I
continued to bisect with the fix unintentionally in place.

So just removing the MEI_NFC_UUID entry from the pn544_mei_tbl[] array
initialization makes things work for me again.

The symptoms are just a hard hang at suspend or shutdown.

This is a pretty regular Intel-only laptop, running Fedora 22.

Any ideas?

                    Linus

I'm looking into this (not sure I get the exact platform to test with)

There was a miss order in how patches were applied, which may confuse bisection even more 
The fix for that was provided in this patch

In commit b144ce2d37619e05afdb0a15676500d76a64b1be
Author: Greg Kroah-Hartman [off-list ref]
Date:   Wed May 27 17:17:27 2015 -0700

    mei: fix up uuid matching


We had  suspend issue that was resolved by a patch bellow, but it's not related to the NFC at all. 
The NFC under Haswell should not be actually operational, I'm not sure if Samuel is planning to support it at all.
Still need to figure out what caused that regression. 
 
commit 3dc196eae1db548f05e53e5875ff87b8ff79f249
Author: Alexander Usyskin [off-list ref]
Date:   Sat Jun 13 08:51:17 2015 +0300

    mei: me: wait for power gating exit confirmation

    Fix the hbm power gating state machine so it will wait till it receives
    confirmation interrupt for the PG_ISOLATION_EXIT message.

Thanks
Tomas