Thanks a lot, Neil, it's a very clear explanation. We'll try more tests on this. Regards, Yu On Fri, Mar 6, 2015 at 9:41 AM, Neil Horman <nhorman@xxxxxxxxxxxxx> wrote: > On Fri, Mar 06, 2015 at 08:51:40AM -0800, Jerry Jerry wrote: >> Hi Neil, >> >> My apology that I didn't make it clear. There are actually two related >> issues, (1) ipv6 requirement, and (2) checksctp hangs. For 2nd issue, >> we are trying to recreate the problem and will get back to you once we >> have the trace. For the 1st issue, here is how we verified: >> >> using "vi /etc/modprobe.d/50-ipv6.conf" to comment out #install ipv6 >> /bin/true, and later using modprobe ipv6 to enable it. The following >> are our steps: >> >> linux165:~/sctp_test/lksctp-tools-1.0.16/src/withsctp >> # ./checksctp >> checksctp: Protocol not supported >> >> linux165:~/sctp_test/lksctp-tools-1.0.16/src/withsctp >> # vi /etc/modprobe.d/50-ipv6.conf (undo comment out ipv6) >> >> linux165:~/sctp_test/lksctp-tools-1.0.16/src/withsctp >> # modprobe ipv6 >> >> linux165:~/sctp_test/lksctp-tools-1.0.16/src/withsctp >> # ./checksctp >> SCTP supported >> > Sorry, didn't realize what you were asking. What I should say is that sctp has > no build time requriements on ipv6. That is to say you could disable ipv6 in > your kernel build and sctp should still work on ipv4 just fine. But if you do > what you suggest above, which is to say, build sctp with ipv6 support, and then > prevent the ipv6 module from loading, sctp won't just fall back to pretending it > can't talk over ipv6. It has load time symbol requirements that will prevent > the module from loading, which is why you get the EOPNOTSUPP error above. > > Neil > >> >> Regards, >> Jerry >> >> On Thu, Mar 5, 2015 at 6:04 AM, Neil Horman <nhorman@xxxxxxxxxxxxx> wrote: >> > On Wed, Mar 04, 2015 at 12:59:21PM -0800, Jerry Jerry wrote: >> >> Hello, >> >> >> >> We had a strange problem using lksctp-tool where checksctp would hang >> >> there on some of our machines and process cannot be killed anyway >> >> (with status d/d+). After some investigation, we found out that >> >> whether ipv6 is enabled could impact the behavior of the library. So, >> >> my question is that, is this a requirement by design or it just >> >> happens to occur that ipv6 is required? Any suggestion to bypass this >> >> (not to rely on ipv6) would be appreciated very much. >> >> >> >> Regards, >> >> Jerry >> > IIRC there should be no ipv6 requierment. >> > >> > Where does the checksctp tool hang? Is it in user space or the kernel? Can you >> > provide a backtrace, either ia gdb if its in userspace or sysrq in the kernel? >> > >> > Best >> > Neil >> > >> >> -- >> >> To unsubscribe from this list: send the line "unsubscribe linux-sctp" in >> >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >> >> -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
