From: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> kvmppc_alloc_host_rm_ops() holds get_online_cpus() while invoking cpuhp_setup_state_nocalls(). cpuhp_setup_state_nocalls() invokes get_online_cpus() as well. This is correct, but prevents the conversion of the hotplug locking to a percpu rwsem. Use cpuhp_setup_state_nocalls_locked() to avoid the nested call. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Alexander Graf <agraf@xxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: kvm@xxxxxxxxxxxxxxx Cc: kvm-ppc@xxxxxxxxxxxxxxx Cc: linuxppc-dev@xxxxxxxxxxxxxxxx --- arch/powerpc/kvm/book3s_hv.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -3336,10 +3336,10 @@ void kvmppc_alloc_host_rm_ops(void) return; } - cpuhp_setup_state_nocalls(CPUHP_KVM_PPC_BOOK3S_PREPARE, - "ppc/kvm_book3s:prepare", - kvmppc_set_host_core, - kvmppc_clear_host_core); + cpuhp_setup_state_nocalls_locked(CPUHP_KVM_PPC_BOOK3S_PREPARE, + "ppc/kvm_book3s:prepare", + kvmppc_set_host_core, + kvmppc_clear_host_core); put_online_cpus(); }