From fddf9055a60dfcc97bda5ef03c8fa4108ed555c5 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 20 Aug 2020 09:13:30 +0200 Subject: lockdep: Use raw_cpu_*() for per-cpu variables Sven reported that commit a21ee6055c30 ("lockdep: Change hardirq{s_enabled,_context} to per-cpu variables") caused trouble on s390 because their this_cpu_*() primitives disable preemption which then lands back tracing. On the one hand, per-cpu ops should use preempt_*able_notrace() and raw_local_irq_*(), on the other hand, we can trivialy use raw_cpu_*() ops for this. Fixes: a21ee6055c30 ("lockdep: Change hardirq{s_enabled,_context} to per-cpu variables") Reported-by: Sven Schnelle Reviewed-by: Steven Rostedt (VMware) Reviewed-by: Thomas Gleixner Acked-by: Rafael J. Wysocki Tested-by: Marco Elver Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20200821085348.192346882@infradead.org --- kernel/locking/lockdep.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 2fad21d345b0..c872e95e6e4d 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -3756,7 +3756,7 @@ void noinstr lockdep_hardirqs_on(unsigned long ip) skip_checks: /* we'll do an OFF -> ON transition: */ - this_cpu_write(hardirqs_enabled, 1); + __this_cpu_write(hardirqs_enabled, 1); trace->hardirq_enable_ip = ip; trace->hardirq_enable_event = ++trace->irq_events; debug_atomic_inc(hardirqs_on_events); @@ -3795,7 +3795,7 @@ void noinstr lockdep_hardirqs_off(unsigned long ip) /* * We have done an ON -> OFF transition: */ - this_cpu_write(hardirqs_enabled, 0); + __this_cpu_write(hardirqs_enabled, 0); trace->hardirq_disable_ip = ip; trace->hardirq_disable_event = ++trace->irq_events; debug_atomic_inc(hardirqs_off_events); -- cgit v1.2.3