On Thu, Oct 20, 2022 at 09:27:37AM +0200, Heiko Carstens wrote: > On Thu, Oct 20, 2022 at 09:23:49AM +0200, Heiko Carstens wrote: > > On Thu, Oct 20, 2022 at 07:16:44AM +0200, Christian Borntraeger wrote: > > > Am 20.10.22 um 00:58 schrieb Paul E. McKenney: > > > > The s390 architecture uses either a cmpxchg loop (old systems) > > > > or the laa add-to-memory instruction (new systems) to implement > > > > this_cpu_add(), both of which are NMI safe. This means that the old > > > > and more-efficient srcu_read_lock() may be used in NMI context, without > > > > the need for srcu_read_lock_nmisafe(). Therefore, add the new Kconfig > > > > option ARCH_HAS_NMI_SAFE_THIS_CPU_OPS to arch/arm64/Kconfig, which will > > > s390 ? > > Ah, this typo is what Christian pointed out; missed that. > > > > > cause NEED_SRCU_NMI_SAFE to be deselected, thus preserving the current > > > > srcu_read_lock() behavior. > > > > > > > > Link: https://lore.kernel.org/all/20220910221947.171557773@xxxxxxxxxxxxx/ > > > > > > > > Suggested-by: Neeraj Upadhyay <quic_neeraju@xxxxxxxxxxx> > > > > Suggested-by: Frederic Weisbecker <frederic@xxxxxxxxxx> > > > > Suggested-by: Boqun Feng <boqun.feng@xxxxxxxxx> > > > > Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx> > > ... > > > > --- > > > > arch/s390/Kconfig | 1 + > > > > 1 file changed, 1 insertion(+) > > > > Not sure what Christian was trying to say with his empty reply :) > > In any case: > > Acked-by: Heiko Carstens <hca@xxxxxxxxxxxxx> I will apply the fix and the ack on my next rebase, thank you both! Thanx, Paul