Kernel 2.6.11: irq 11: nobody cared!

kernel: irq 11: nobody cared!<br></br>
kernel: Disabling IRQ #11

Three days before I tried for the very first time the new Fedora Core 4 distribution. On my new (second hand) ThinkPad T20. The collection, the installation process and the distro are perfect as much as can be. Fedora is as always state-of-the-art collection. Actually I can’t even dream about some other distribution better than Fedora – digitally signed packages, perfect security, very sexy desktop, great development environment (now with eclipse and tomcat), finally MySQL 4.1 inside and unbelievable support with updates. Fedora project team is one of the best community teams ever.

Well, everything is perfect but not with kernel 2.6.11 (actually the situation is the same with FC3 and the newest kernel update which is 2.6.11 as well). Kernel 2.6.10 works fine. There are several hardware configurations where the USB, sound, video or/and networking cannot share some IRQ. In my case this was IRQ #11.

Actually, this is not Fedora related problem. Every distribution with kernel 2.6.11 is affected but only on some specific hardware configurations such as ThinkPad T20 one. There are complains that on some motherboards you can’t even install Linux with 2.6.11. My other laptop ThinkPad T40 for example works just fine. My colleagues tested FC4 on T41 and T42 – there are no problems at all.

On T20 video is OK but USB, sound and network (PCMCIA) cannot work together. Actually USB works somehow. I have no sound and which is the biggest problem no network. The funny thing is that it is possible to install FC4 on T20 via the network, but after finishing the installation and first reboot there is no any network anymore 😉

The solution is simple (if you can install FC4 with 2.6.11 kernel on your motherboard). After sucessful FC4 installation just find the latest 2.6.10 FC3 kernel and rpm -ivh it on your FC4. After that do not update your kernel until the problem is solved. Well, there are security problems related to 2.6.10 and before but… Actually for my T20 I’ve downgraded my kernel to 2.6.10-1.770_FC3. Well, you have to disable SELinux when booting this kernel adding selinux=0 as parameter in /boot/grub/grub.conf or downgrade your selinux-policy package also.

Kernel 2.6.12 was born this night. I didn’t check yet but I hope the problem is fixed 😉