On Wed, 2009-03-18 at 23:01 +0100, Philippe Gerum wrote: > Philippe Gerum wrote: > > Andreas Glatz wrote: > >> Hi, > >> > >> I got a kernel crash because inside xnheap_test_and_free a > >> invalid pointer contained in variable 'nextpage' is dereferenced: > >> > > > > <snip> > > > > This turned out to be caused by an out-of-bound write triggered by the > > streaming > > output service. > > > > The patch below fixes the issue; it has been committed to both the > > maintenance > > (v2.4.x) and development branches.
Great! This fixes the bug! Many thanks! > > > > Sidenote: your test scenario involves echoing some data to /dev/rtp0 for > > triggering the issue; this will now work, but you won't get that input > > available > > to rt_pipe_read(). In case you wonder why, the reason is that 'echo' will > > exit > > immediately after sending the bytes, which will cause the user-space side > > of the > > channel to be closed, and the input queue (the one that goes user -> > > kernel) to > > be flushed from any pending data. > > > > ...unless your polling RT read loop wakes up at the right time and manages to > preempt the Linux kernel shortly after the echo sent the bytes, in which case > you will receive the data, but that is obviously not the most frequent > situation. > Actually we don't use echo or cat to write to/read from the pipe. I just used it to describe the failure. We are using a patched version of minicom to read from/write to the pipe. Probably you know that you can use minicom to connect to a unix-socket, I just went ahead and patched it so that you can connect to a named pipe. Anyways, Thanks a lot! Andreas _______________________________________________ Xenomai-core mailing list Xenomai-core@gna.org https://mail.gna.org/listinfo/xenomai-core
