The driver currently sets the handler data and the chained handler in two separate steps. This creates a theoretical race window where an interrupt could fire after the handler is set but before the data is assigned, leading to a NULL pointer dereference.
Replace the two calls with irq_set_chained_handler_and_data() to set both the handler and its data atomically under the irq_desc->lock. Signed-off-by: Chen Ni <[email protected]> --- arch/powerpc/platforms/44x/uic.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/platforms/44x/uic.c b/arch/powerpc/platforms/44x/uic.c index 85daf841fd3f..50ce4a77ca94 100644 --- a/arch/powerpc/platforms/44x/uic.c +++ b/arch/powerpc/platforms/44x/uic.c @@ -309,8 +309,8 @@ void __init uic_init_tree(void) cascade_virq = irq_of_parse_and_map(np, 0); - irq_set_handler_data(cascade_virq, uic); - irq_set_chained_handler(cascade_virq, uic_irq_cascade); + irq_set_chained_handler_and_data(cascade_virq, + uic_irq_cascade, uic); /* FIXME: setup critical cascade?? */ } -- 2.25.1
