Linus,

Please pull the latest irq-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
irq-urgent-for-linus

   HEAD: dc9b229a58dc0dfed34272ff26c6d5fd17c674e0 genirq: Allow irq chips to 
mark themself oneshot safe

 Thanks,

        Ingo

------------------>
Thomas Gleixner (1):
      genirq: Allow irq chips to mark themself oneshot safe


 include/linux/irq.h |    1 +
 kernel/irq/manage.c |   15 ++++++++++++++-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/include/linux/irq.h b/include/linux/irq.h
index 553fb66..216b0ba 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -349,6 +349,7 @@ enum {
        IRQCHIP_MASK_ON_SUSPEND         = (1 <<  2),
        IRQCHIP_ONOFFLINE_ENABLED       = (1 <<  3),
        IRQCHIP_SKIP_SET_WAKE           = (1 <<  4),
+       IRQCHIP_ONESHOT_SAFE            = (1 <<  5),
 };
 
 /* This include will go away once we isolated irq_desc usage to core code */
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 8c54823..2e326d1 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -960,6 +960,18 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, 
struct irqaction *new)
        }
 
        /*
+        * Drivers are often written to work w/o knowledge about the
+        * underlying irq chip implementation, so a request for a
+        * threaded irq without a primary hard irq context handler
+        * requires the ONESHOT flag to be set. Some irq chips like
+        * MSI based interrupts are per se one shot safe. Check the
+        * chip flags, so we can avoid the unmask dance at the end of
+        * the threaded handler for those.
+        */
+       if (desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)
+               new->flags &= ~IRQF_ONESHOT;
+
+       /*
         * The following block of code has to be executed atomically
         */
        raw_spin_lock_irqsave(&desc->lock, flags);
@@ -1033,7 +1045,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, 
struct irqaction *new)
                 */
                new->thread_mask = 1 << ffz(thread_mask);
 
-       } else if (new->handler == irq_default_primary_handler) {
+       } else if (new->handler == irq_default_primary_handler &&
+                  !(desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)) {
                /*
                 * The interrupt was requested with handler = NULL, so
                 * we use the default primary handler for it. But it
--
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