[PATCH v2 0/2] bus: CCN/CCI: Fix use of smp_processor_id()

From: Marc Zyngier
Date: Tue Oct 03 2017 - 13:15:00 EST


I've just noticed that both the CCI and CCN drivers have a small
buglet in that they call smp_processor_id() from preemptible context,
which is frown upon (having just booted a 4.13 kernel with
DEBUG_PREEMPT on my Seattle, I was surprised to be greeted with a nice
backtrace...).

I've tested the CCN patch on the same Seatle box, but I've only
compile-tested the equivalent CCI patch (which is obviously correct --
famous last words...).

Thanks,

M.

* From v1: Keep the current CPU refcount until we have registered the
CPU notifiers, making sure we don't race against a surprise hotplug
off.

Marc Zyngier (2):
bus: arm-ccn: Fix use of smp_processor_id() in preemptible context
bus: arm-cci: Fix use of smp_processor_id() in preemptible context

drivers/bus/arm-cci.c | 7 +++++--
drivers/bus/arm-ccn.c | 4 +++-
2 files changed, 8 insertions(+), 3 deletions(-)

--
2.11.0