For F-13 (and RHEL-6, I'll clone this bug), mdraid set activation has moved from rc.sysinit to udev rules. This includes the activation of isw / imsm BIOS RAID sets.
In order for the udev rules to be able to honor the noiswmd kernel cmdline option a udev property should be set when this option is present so that the udev rules can check for this.
The rules already check for rd_NO_MDIMSM, this was my idea / suggestion as
I assumed this property would be propagated from the initrd udev to the normal one, but it is not.
Still it would be the easiest to use rd_NO_MDIMSM as property name.
udev-153-2.fc13 has been submitted as an update for Fedora 13.
udev-153-2.fc13 has been pushed to the Fedora 13 testing repository. If problems still persist, please make note of it in this bug report.
If you want to test the update, you can install it with
su -c 'yum --enablerepo=updates-testing update udev'. You can provide feedback for this update here: http://admin.fedoraproject.org/updates/udev-153-2.fc13
udev-153-3.fc13 has been submitted as an update for Fedora 13.
udev-153-3.fc13 has been pushed to the Fedora 13 stable repository. If problems still persist, please make note of it in this bug report.