On 12 July 2016 at 15:26, Joe Stringer <j...@ovn.org> wrote: > This series fixes a couple of crashes that may occur due to the backports of > the inet_fragment.c code from upstream. These are primarily related to cases > where a fragment is received and cached in the OVS fragment handling code > with a timer attached to expire it, then the OVS kernel module is removed > before the timer fires. When the timer fires, it attempts to invoke a function > residing within the memory that has been released by OVS, leading to the error > "Fatal exception in interrupt". > > These bugs are fairly easy to reproduce using the existing "system-traffic" > testsuite in conjunction with the backported OVS kernel module in the tree. > > The first patch is a simple fix for an issue of this variety on IPv6. However, > even for the IPv6 expiry test there is still another similar bug that can be > triggered even with this patch. > > In the second patch, I reviewed how much of the fragmentation backport was > strictly required for the IP/IPv6 fragmentation handling that we need to > perform in OVS. There are multiple variations on the shared fragment handling > logic upstream, primarily from kernels 3.10-3.17 and 3.17-4.2, but the > internal > kernel APIs have been consistent enough that with some minor touchups in how > inet_fragment code is invoked, we can always rely on upstream versions of > these > functions. As such, this patch ripped out the majority of inet_fragment.c, > leaving a little init/exit code remaining. This solves the remaining issues on > updated kernel versions. > > Patches 3-6 do some additional cleanup of functions I noticed are available on > supported kernels 3.10+. > > I tested this series on CentOS 3.10.0-327 and a variety of Ubuntu kernels > 3.13-4.2. Note that the kernel testsuite will still trigger some issues on > earlier Ubuntu 3.13 kernels (for example 3.13.0-24), however these are due to > upstream kernel bugs that have been fixed in subsequent kernel updates. People > using Ubuntu 14.04 should seriously consider upgrading their kernel to at > least > version 3.13.0-68 (if not newer) if they intend to use the OVS kernel module > from the tree in conjunction with conntrack features. > > These bugs likely affect the branch-2.5 kernel module, although the kernel > testsuite at that release did not include tests which would trigger the bugs > so > the issues are less obvious there. Once this has settled down I would like to > consider patches 1-3 for backport.
Thanks for the reviews, I applied this series to master. I intend to give this a couple of weeks to see if anything drops out before backporting to branch-2.5. _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
