I suspect some kind of infinite loop or blocking in kernelspace Reproducible: Always Actual Results: Bash hangs Expected Results: Caches should flush. still going on 5 minutes with an idle system and it's still hung, with 100 percent cpu time allocated to system.
Can you try to build bash and the kernel with debugging symbols and obtain a backtrace with gdb? That way we can get to see where it hangs. There are also some other hang related options in the debugging section that might yield more details. Make sure to take a look at dmesg as well; or well, at least if that's a possibility with a hung terminal. Though on the other hand, you can look at /var/log/messages (or journalctl on systemd) as an alternative.
Update: It *eventually* finishes, and I noticed that buffers usage also goes down to near zero. Repeated invocation is quicker but still takes a second. I'll try to rebuild the kernel. Bash is already ggdb3 so I'll leave it alone. Will attempt to rebuild kernel with debug.
(In reply to shentino from comment #2) > Update: > > It *eventually* finishes, and I noticed that buffers usage also goes down to > near zero. > > Repeated invocation is quicker but still takes a second. > > I'll try to rebuild the kernel. Bash is already ggdb3 so I'll leave it > alone. > > Will attempt to rebuild kernel with debug. Were you able to reproduce with debug symbols to get more information?
I've moved on to 3.13 now so I'm closing this as obsolete. Also I do not yet know how to debug a kernel.
