SMP enabled 2.6.21 with full realtime preemtion for i686 only. works fine on my desktop and laptop - suspends to disk on the latter, but does not recover after a suspend to RAM! (the debian 2.6.18-4 does!)
kqemu and many other modules can be installed with the module assistant m-a a-i kqemu. some modules require minor patches (change SA_SHIRQ in the request_irq functions to IRQF_SHARED, and add a few missing struct when you get a warning..)
I have not yet build all the debian header packages.. drop me a line if you need 'em. most likely you want to get the souce, slightly modify the config and roll your own:
cd /usr/src/ tar xjf linux-source-2.6.21-rc3-rt0-rg2.tar.bz2 cd linux-source-2.6.21-rc3-rt0-rg2 make menuconfig make-kpkg clean CONCURRENCY_LEVEL=2 time make-kpkg kernel_image cd .. dpkg -i linux-image-2.6.21-rc3-rt0-rg2_2.6.21-rc3-rt0*-10.00.custom_i386.deb
download, install width dpkg -i <linux-…>.deb. you might need to run update-initramfs -k all -u && update-grub, but it should not be necessary.
slightly modified Rui's rtirq init script to match the debian paths (/etc/default/rtirq). - enable with sysv-rc-conf or make /etc/rc?.d/ links by hand.