Description of problem: We are looking at the RT kernel on an Intel Nehalem whitebox and running into problems. The box boots fine with RHEL5.3RC2 (2.6.18-128.el5) but fails to boot with the MRG1.1 kernel (2.6.24.7-95.el5rt) Version-Release number of selected component (if applicable): 2.6.24.7-95.el5rt How reproducible: always Steps to Reproduce: 1.Install RHEL5.3RC2 and MRG 1.1 kernel 2. 3. Actual results: Booting into the RHEL5.3RC2 kernel works fine. Working either into the rt kernel, or the rtvanilla kernel results in disabled interrupts and the OS does not boot (cannot find root volume). Please see attached screenshots. Expected results: Additional info: Under the RT kernel, IRQ 16 is disabled. Under the RTvanilla kernel, IRQ 11 is disabled. Both result in not booting. The suggested use of irqpoll and ioapic_level_quirk=1 do not make any difference.
Created attachment 328984 [details] Screenshot of boot panic
Created attachment 328985 [details] sosreport of affected system
Created attachment 329027 [details] Updated sosreport In this sosreport, the latest boot is into the RHEL5.3 kernel with no kernel options specified (other than crashkernel). Previous boots specified 'noht notsc noapic nolapic' which are in our standard build. Nick
Have you tried booting the kernel with ioapic_level_quirk=1 on the command line?