> Could http://bugs.debian.org/511334 be related to your problem? There's a > link to patch in one of the last messages.
> See especially messages #57 and #65. It's possible that they may be related. The difference, though, is that the user in problem number 511334 was running in a virtual machine under z/VM 5.2.0, which in turn was running on Flex-ES or Hercules machines, both of which are mainframe emulators. I am running on a real IBM mainframe. It is an Integrated Facility for Linux (IFL) processor on a z/890 (2086) machine, dedicated to an IFL-only LPAR. z/VM 5.4.0 runs under that, and my Linux virtual machine runs under that. His boots were hanging much earlier in the boot process until he applied the patch. After applying the patch, he was able to get up to the point where the DASD drivers are supposed to load, but was not able to get further than that. The user was optimistic that his problem from that point on was simply a matter of a faulty RAM disk, but I see no evidence that he was able to get the permanent root file system mounted under any scenario. I predict that he is still stuck at that point. My problem, on the other hand, has always been that the kernel hangs right before the permanent root file system gets mounted. I've always been able to get that far but no farther. For me, the key is that the s390x kernel works flawlessly, but the s390 kernel hangs. I suspect that the problem is that an instruction which is only valid in z/Architecture mode is being issued in ESA mode, and that is what is causing the problem. That's just a hunch.