Description of problem: NetworkManager prefers to run /usr/sbin/pppoe on a pty for PPPoE connections, rather than using the rp-pppoe.so plugin. This both costs CPU time, and reduces the feature set of PPPoE on Fedora. Version-Release number of selected component (if applicable): 0.9.10.0-14.git20140704.fc21 How reproducible: Always Steps to Reproduce: 1. Set up a PPPoE connection 2. Connect 3. Note via ps that /usr/sbin/pppoe is in use, rather than the rp-pppoe.so plugin, and thus that PPPoE jumbograms are not available (1492 MTU instead of the supported 1500 MTU on the PPP connection) Actual results: PPPoE connections use /usr/sbin/pppoe to handle the PPPoE side, which consumes more CPU time, *and* doesn't permit the use of RFC 4638 jumbograms for 1500 MTU. Expected results: PPPoE connections use the rp-pppoe.so plugin, to get the kernel to handle the PPPoE side, for reduced CPU use under load and RFC 4638 jumbograms.
Attached patch against F21's NM fixes this for me. I'll be filing a version of the patch against git master for upstream's consideration, and will update this bug when I've done so.
Created attachment 980241 [details] kernel pppoe patch
https://bugzilla.gnome.org/show_bug.cgi?id=742939 is the upstream report - there's a kernel patch to cover the reason for NetworkManager regressing to userspace PPPoE, and two patches to NetworkManager to make it able to use either PPPoE implementation and to sort out PPPoE MTUs.
The kernel patch is in net-next since 2015-03-04. https://git.kernel.org/cgit/linux/kernel/git/davem/net-next.git/commit/?id=287f3a943fef58c5c73e42545169443be379222f
Might also want this additional kernel patch. Simon, does Felix's patch here look legit? https://patchwork.ozlabs.org/patch/470384/
(In reply to Dan Williams from comment #5) > Might also want this additional kernel patch. Simon, does Felix's patch > here look legit? > > https://patchwork.ozlabs.org/patch/470384/ It does, yes.
This package has changed ownership in the Fedora Package Database. Reassigning to the new owner of this component.
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