From 0449fc4eead7af2523cd12f312b856dfa93731ed Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Tue, 17 Nov 2020 11:37:51 +0100 Subject: [PATCH] iio: sysfs-trigger: Mark irq_work to expire in hardirq context Mark the IIO sysfs-trigger irq_work with IRQ_WORK_HARD_IRQ to ensure that it is always executed in hard interrupt context, even with PREEMPT_RT=y. The IIO sysfs-trigger irq_work needs to run in hard interrupt context since it will end up calling generic_handle_irq() which has the requirement to run in hard interrupt context. Note that the IRQ_WORK_HARD_IRQ flag, while it exists, does not seem to do anything in the mainline kernel yet. It does have an effect in the RT patchset though and presumably this is sooner or later going to be added to mainline as well. Reported-by: Christian Eggers Signed-off-by: Lars-Peter Clausen Acked-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/20201117103751.16131-2-lars@metafoo.de Signed-off-by: Jonathan Cameron --- drivers/iio/trigger/iio-trig-sysfs.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/iio/trigger/iio-trig-sysfs.c b/drivers/iio/trigger/iio-trig-sysfs.c index e09e580..10a3fd2 100644 --- a/drivers/iio/trigger/iio-trig-sysfs.c +++ b/drivers/iio/trigger/iio-trig-sysfs.c @@ -161,6 +161,7 @@ static int iio_sysfs_trigger_probe(int id) iio_trigger_set_drvdata(t->trig, t); init_irq_work(&t->work, iio_sysfs_trigger_work); + atomic_set(&t->work.flags, IRQ_WORK_HARD_IRQ); ret = iio_trigger_register(t->trig); if (ret) -- 2.7.4