genirq: Mark polled irqs and defer the real handler
With the chip.end() function gone we might run into a situation where
a poll call runs and the real interrupt comes in, sees IRQ_INPROGRESS
and disables the line. That might be a perfect working one, which will
then be masked forever.
So mark them polled while the poll runs. When the real handler sees
IRQ_INPROGRESS it checks the poll flag and waits for the polling to
complete. Add the necessary amount of sanity checks to it to avoid
deadlocks.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/irq.h b/include/linux/irq.h
index f5e9003..e32b64c 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -71,6 +71,7 @@
#define IRQ_SUSPENDED 0x04000000 /* IRQ has gone through suspend sequence */
#define IRQ_ONESHOT 0x08000000 /* IRQ is not unmasked after hardirq */
#define IRQ_NESTED_THREAD 0x10000000 /* IRQ is nested into another, no own handler thread */
+#define IRQ_POLL_INPROGRESS 0x20000000 /* IRQ poll is in progress */
#define IRQF_MODIFY_MASK \
(IRQ_TYPE_SENSE_MASK | IRQ_NOPROBE | IRQ_NOREQUEST | \