I'm afraid I reproduced this again using the kernel 4.17.2 where I see the
following commit:

commit 9ca5a2ae4259e7aec8efb0db0f6ec721a6854c54
Merge: bee797529d7c c62ec4610c40
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Thu May 24 08:49:56 2018 -0700

    Merge tag 'pm-4.17-rc7' of
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

    Pull power management fix from Rafael Wysocki:
     "Fix a regression from the 4.15 cycle that caused the system suspend
      and resume overhead to increase on many systems and triggered more
      serious problems on some of them (Rafael Wysocki)"

    * tag 'pm-4.17-rc7' of
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
      PM / core: Fix direct_complete handling for devices with no callbacks

I'll attach the boot process with the traceback soon.