It looks if events are preceeding me, but here is what I've found so far: 1. The earlier comments about using a custom kernel are just a red herring. I build a custom kernel using the standard lowlatency configuration and (not surprisingly) the bcmwl dkms module failed to compile.
2. A diff between the distro /boot/config-3.8.0-27-lowlatency and config-3.8.0-27-generic shows VERY few changes, mainly PREEMPT stuff and (probably) consequential LOCK variables - see attachment for full diff. 3. I built my custom kernel from the distro source package, not git. I intend to hack the patch proposed in https://bugs.launchpad.net/ubuntu/+source/linux-lowlatency/+bug/1154036 (posted in march 2013!!) and try to apply it to my kernel source. ** Patch added: "diff between lowlatency and generic configs" https://bugs.launchpad.net/ubuntu/+source/bcmwl/+bug/1156138/+attachment/3759028/+files/config-standard.diff -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to bcmwl in Ubuntu. https://bugs.launchpad.net/bugs/1156138 Title: bcmwl-kernel-source fails to build on lowlatency kernel [FATAL: modpost: GPL-incompatible module wl.ko uses GPL-only symbol '__rcu_read_unlock'] Status in “bcmwl” package in Ubuntu: Confirmed Bug description: Ubuntu 13.04 ProblemType: Package DistroRelease: Ubuntu 13.04 Package: bcmwl-kernel-source 6.20.155.1+bdcom-0ubuntu6 ProcVersionSignature: Ubuntu 3.8.0-13.22-generic 3.8.3 Uname: Linux 3.8.0-13-generic i686 NonfreeKernelModules: wl ApportVersion: 2.9.1-0ubuntu1 Architecture: i386 DKMSKernelVersion: 3.8.0-12-lowlatency Date: Sat Mar 16 23:37:03 2013 InstallationDate: Installed on 2013-01-03 (72 days ago) InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Release i386 (20121017.2) MarkForUpload: True PackageVersion: 6.20.155.1+bdcom-0ubuntu6 SourcePackage: bcmwl Title: bcmwl-kernel-source 6.20.155.1+bdcom-0ubuntu6: bcmwl kernel module failed to build UpgradeStatus: Upgraded to raring on 2013-03-12 (4 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/bcmwl/+bug/1156138/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp