BUG Report: "config KVM" selects PREEMPT_NOTIFIERS, but it should also select PREEMPT (Vanilla Kernel 2.6.30)

Walther Maldonado
2009-06-29T23:09:21Z

Good day,

Today when attempting to compile and install the KVM module (kernel 2.6.30), inserting the module would error with a number of unresolved symbols such as preempt_notifier_register() not found.

Some code-browsing revealed that, even though the kvm KConfig setting "KVM" does select PREEMPT_NOTIFIERS, in include/linux/preempt.h, said define will not cause the expected functions to be defined unless CONFIG_PREEMPT is also selected.

But I don't have CONFIG_PREEMPT (Preemptible Kernel), my kernel was configured with CONFIG_PREEMPT_VOLUNTARY (Voluntary Kernel Preemption). Since the define CONFIG_PREEMPT_NOTIFIERS is used in other files other than preempt.h, the bug might be in KVM's Kconfig file (in my case, arch/x86/kConfig) not selecting/depending on the right config parameters.

Cheers,
Walther

PS: If there is a need to reply, please do so directly as I am not subscribed to the mailing list.