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>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/irq.h b/include/linux/irq.h
index f5e900309d21..e32b64ccdc89 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -71,6 +71,7 @@ typedef	void (*irq_flow_handler_t)(unsigned int irq,
 #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 | \