On Mon, Apr 08, 2013 at 03:45:31PM -0700, Doug Anderson wrote: > Hi, > > On Mon, Apr 8, 2013 at 3:17 PM, Stephen Warren <swarren@xxxxxxxxxxxxx> wrote: > >> Anyway, I've just pushed a splitup of that commit (carved in 3 pieces) > >> into vfs.git#pipe-splitup; could you check which part triggers that > >> hang? Should propagate in a few... > > > > It looks like "pipe: unify ->release() and ->open()" introduces the > > problem. Note that I had to add a prototype for fifo_open() before the > > structs that reference it for that commit to compile. > > It sounds like Stephen has provided you the info you needed so not > doing any extra testing now, but I figured I'd chime in that I hit > problems this morning with linux-next and it appears to be the same > thing. I did a revert of 9984d7394618df9 and (plus a revert of a > handful of patches to the same file) and problems are resolved. The > failure case is really weird in that everything works well booting to > a simple /bin/bash but fails when you do more complex tasks. > > Anyway: If you need some extra testing feel free to CC me. Folks, see if vfs.git#experimental works for you; the PITA had apparently been caused by change of open() semantics for /proc/<pid>/fd/<some_pipe> - it started to behave like a FIFO, i.e. wait for peer to show up. Normally that's not a problem, but if you have closed e.g. the write end of a pipe and try to open /proc/<pid>/fd/<read_end_of_pipe>, you'll get open() waiting for writers to appear. Which isn't what we used to do here (open succeeded immediately) and apparently that was enough to trip drakut. Branch head should be at 574179469f7370aadb9cbac1ceca7c3723c17bee. -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html