I have two PowerPC platforms that I'm upgrading to a 6.6 kernel, and both hang on boot right before my initramfs. I bisected the hang to this commit: https://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git/commit/?h=v6.6-rc6-rt10&id=b33022a48c797082dead4034e84f0adfbc5b1983 That commit is somewhat large, but I've narrowed it down to this part of the commit: diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c index 9f144588b33643..c4f6d3c69ba9d3 100644 --- a/arch/powerpc/kernel/interrupt.c +++ b/arch/powerpc/kernel/interrupt.c @@ -395,15 +395,11 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs) /* Returning to a kernel context with local irqs enabled. */ WARN_ON_ONCE(!(regs->msr & MSR_EE)); again: - if (IS_ENABLED(CONFIG_PREEMPTION)) { + if (IS_ENABLED(CONFIG_PREEMPT)) { ... Reverting this particular line fixes the hang. The change doesn't look quite right to me, since CONFIG_PREEMPT doesn't seem related to the other changes happening in that commit, but maybe there is something I don't see. Does this change make sense? I'm happy to send a patch reverting this particular line. Thanks, Robert
