Re: tipc_udp_send_msg oops in 4.4 when setting link tolerance

From: Tommi Rantala
Date: Wed Nov 15 2017 - 04:43:18 EST


On 14.11.2017 13:35, Jon Maloy wrote:
Found it, the missing patch is this one (9b3009604b8e does not help):

commit d01332f1acacc0cb43a61f4244dd2b846d4cd585
Author: Richard Alpe <richard.alpe@xxxxxxxxxxxx>
Date: Mon Feb 1 08:19:56 2016 +0100

tipc: fix link attribute propagation bug


It does not apply as-is to 4.4, so backported it, see below.
Does it look good? I can send it forward to Greg for inclusion in 4.4.

Yes. I would be very grateful if you do.

OK, sent the patch to stable@xxxxxxxxxxxxxxx

But with this patch included, I can easily reproduce the "BUG: Bad page state
in process git" issue also in 4.4 like this:

$ tipc link set tolerance 100 link $LINKNAME $ cd /tmp && git clone
/path/to/linux-stable

I can try to debug that a bit more to see if I can figure it out.

I would appreciate that. If this turns out to also be an already fixed bug (most likely) you can send that directly to GKH too.
If you find a bug that requires a new patch send it to tipc-discussion for review first.

Finally, I want to say that I very much appreciate users like you, who try solving the problems themselves and contribute to the code.
We are right now in an upgrade phase of TIPC, where we have been/are adding new features to TIPC (overlapping ring neighbor monitoring, group communication, new addressing model, performance improvements...) which inevitably entail some new bugs, but I expect the frequency of these changes/improvements to TIPC go down in a few months, and with that the number of fixes needed.

Thanks!

After more testing, I noticed that I could only reproduce the "BUG: Bad page state" in a single machine, so maybe something wrong with the machine, and not with tipc.

-Tommi