Hi, On Thu, Jul 19, 2012 at 11:11:50AM -0400, Alan Stern wrote: > On Thu, 19 Jul 2012, Andreas Mohr wrote: > > > Hi, > > > > Yesterday I was surprised to see that with *another* external USB disk > > happening to be connected before boot, > > the system booted with root partition device sdb1 assigned rather than sda1. > > Not thinking much, I then proceeded putting the system into suspend, > > Do you mean "suspend" or "hibernate"? Doh - S2R. I don't do persistent hibernate here (writing some 1GB of data to flash-based storage each time possibly isn't all too healthy anyway). > Can you reproduce the problem? Will retry soonish. > > http://lists.linux-foundation.org/pipermail/linux-pm/2009-November/023101.html > > Netbook Acer Aspire One A110L. > > Running 3.5.0-rc7+ here (yes ma'am, bleeding edge tester :). > > Was the first time to attempt resume with an additional device remaining > > connected, IIRC - that -rc7 thing likely doesn't play much of a role here. > > A bit hesitant to (dis-)prove the bug's "regression flag" with another version > > since random possibly succeeding I/O accesses to incompatible devices > > are not necessarily my thing (or is this safe to attempt again? Any more > > specific session info one would need?). > > Well, the dmesg log would help. If you still think the USB layer is at > fault then you should enable CONFIG_USB_DEBUG. Maybe I can get this successfully off the machine next time, by pre-caching required binaries prior to initiating a non-working resume. > > So, again, possibly USB persistence is bug-broken? > > You don't have any good evidence to suggest that. None of the > information you provided indicates that any USB device nodes (such as > /dev/bus/usb/001/002) got mixed up. All you know is that the > block-layer device nodes (such as /dev/sda2) got changed. OK - so you're trying in vain to tell dense me that I'm supposed to take note of the *non-changing* (i.e., correctly "persistent") USB device ID scheme rather than the roguely changing device nodes. To which I say that unfortunately I don't have a pre/post comparison at this moment yet. > Furthermore, if USB persist were broken then the symptoms would be > different. Instead of starting with a root partition at sdb1 and then > finding it at sda1, you would have found it gone completely and there > would be _new_ devices labelled sdc and sdd. Ah, yeah - I tend to know *this* other effect, too... > Alan Stern Thanks a ton for your reply! Now I know that there's a tendency to better look on the other side (block device layer etc.) and analyze things there, once it's established that USB topology ID numbering in fact did persist. Andreas Mohr -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
