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* [PATCH 1/9] irq: add irq_set_chained_handler_and_data()
@ 2015-06-16 22:06 Russell King
  2015-06-16 22:29 ` [PATCH] GPU: ipu: fix lockup caused by pending chained interrupts Russell King
  2015-06-17 14:10 ` [PATCH 1/9] irq: add irq_set_chained_handler_and_data() Thomas Gleixner
  0 siblings, 2 replies; 5+ messages in thread
From: Russell King @ 2015-06-16 22:06 UTC (permalink / raw
  To: linux-arm-kernel

Driver authors seem to get the ordering of irq_set_chained_handler()
and irq_set_handler_data() wrong - ordering the former before the
latter.  This opens a race window where, if there is an interrupt
pending, the handler will be called between these two calls,
potentially resulting in an oops.

Provide a single interface to set both of these together, especially
as that's commonly what is required.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
It probably makes sense to convert everything over to this new
registration function, and kill all users of irq_set_chained_handler()
to prevent this problem recurring.  Thoughts?

 include/linux/irq.h |  9 +++++++++
 kernel/irq/chip.c   | 45 ++++++++++++++++++++++++++++++++++-----------
 2 files changed, 43 insertions(+), 11 deletions(-)

diff --git a/include/linux/irq.h b/include/linux/irq.h
index 62c6901cab55..4942cbc379bb 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -517,6 +517,15 @@ irq_set_chained_handler(unsigned int irq, irq_flow_handler_t handle)
 	__irq_set_handler(irq, handle, 1, NULL);
 }
 
+/*
+ * Set a highlevel chained flow handler and its data for a given IRQ.
+ * (a chained handler is automatically enabled and set to
+ *  IRQ_NOREQUEST, IRQ_NOPROBE, and IRQ_NOTHREAD)
+ */
+void
+irq_set_chained_handler_and_data(unsigned int irq, irq_flow_handler_t handle,
+				 void *data);
+
 void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set);
 
 static inline void irq_set_status_flags(unsigned int irq, unsigned long set)
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index eb9a4ea394ab..92bed9010bc6 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -719,15 +719,9 @@ void handle_percpu_devid_irq(unsigned int irq, struct irq_desc *desc)
 }
 
 void
-__irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
-		  const char *name)
+__irq_do_set_handler(struct irq_desc *desc, irq_flow_handler_t handle,
+		     int is_chained, const char *name)
 {
-	unsigned long flags;
-	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
-
-	if (!desc)
-		return;
-
 	if (!handle) {
 		handle = handle_bad_irq;
 	} else {
@@ -749,13 +743,13 @@ __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 			 * right away.
 			 */
 			if (WARN_ON(is_chained))
-				goto out;
+				return;
 			/* Try the parent */
 			irq_data = irq_data->parent_data;
 		}
 #endif
 		if (WARN_ON(!irq_data || irq_data->chip == &no_irq_chip))
-			goto out;
+			return;
 	}
 
 	/* Uninstall? */
@@ -774,12 +768,41 @@ __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 		irq_settings_set_nothread(desc);
 		irq_startup(desc, true);
 	}
-out:
+}
+
+void
+__irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
+		  const char *name)
+{
+	unsigned long flags;
+	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
+
+	if (!desc)
+		return;
+
+	__irq_do_set_handler(desc, handle, is_chained, name);
 	irq_put_desc_busunlock(desc, flags);
 }
 EXPORT_SYMBOL_GPL(__irq_set_handler);
 
 void
+irq_set_chained_handler_and_data(unsigned int irq, irq_flow_handler_t handle,
+				 void *data)
+{
+	unsigned long flags;
+	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
+
+	if (!desc)
+		return;
+
+	__irq_do_set_handler(desc, handle, 1, NULL);
+	desc->irq_data.handler_data = data;
+	
+	irq_put_desc_busunlock(desc, flags);
+}
+EXPORT_SYMBOL_GPL(irq_set_chained_handler_and_data);
+
+void
 irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
 			      irq_flow_handler_t handle, const char *name)
 {
-- 
2.1.0

^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH] GPU: ipu: fix lockup caused by pending chained interrupts
  2015-06-16 22:06 [PATCH 1/9] irq: add irq_set_chained_handler_and_data() Russell King
@ 2015-06-16 22:29 ` Russell King
  2015-06-19 14:36   ` Philipp Zabel
  2015-06-17 14:10 ` [PATCH 1/9] irq: add irq_set_chained_handler_and_data() Thomas Gleixner
  1 sibling, 1 reply; 5+ messages in thread
From: Russell King @ 2015-06-16 22:29 UTC (permalink / raw
  To: linux-arm-kernel

Even with the oops fixed by a previous patch, the system still fails to
kexec, due to a stuck chained interrupt locking the system.  We must
disable the child interrupts prior to setting up the irq chip to ensure
we don't get stuck here.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
Maybe this is all that's really needed... would also be nice if this
path had an etry in MAINTAINERS...

 drivers/gpu/ipu-v3/ipu-common.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/ipu-v3/ipu-common.c b/drivers/gpu/ipu-v3/ipu-common.c
index 6d2f39d36e44..00f2058944e5 100644
--- a/drivers/gpu/ipu-v3/ipu-common.c
+++ b/drivers/gpu/ipu-v3/ipu-common.c
@@ -1107,6 +1107,9 @@ static int ipu_irq_init(struct ipu_soc *ipu)
 		return ret;
 	}
 
+	for (i = 0; i < IPU_NUM_IRQS; i += 32)
+		ipu_cm_write(ipu, 0, IPU_INT_CTRL(i / 32));
+
 	for (i = 0; i < IPU_NUM_IRQS; i += 32) {
 		gc = irq_get_domain_generic_chip(ipu->domain, i);
 		gc->reg_base = ipu->cm_reg;
-- 
2.1.0

^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 1/9] irq: add irq_set_chained_handler_and_data()
  2015-06-16 22:06 [PATCH 1/9] irq: add irq_set_chained_handler_and_data() Russell King
  2015-06-16 22:29 ` [PATCH] GPU: ipu: fix lockup caused by pending chained interrupts Russell King
@ 2015-06-17 14:10 ` Thomas Gleixner
  2015-06-17 19:38   ` Russell King - ARM Linux
  1 sibling, 1 reply; 5+ messages in thread
From: Thomas Gleixner @ 2015-06-17 14:10 UTC (permalink / raw
  To: linux-arm-kernel

On Tue, 16 Jun 2015, Russell King wrote:

> Driver authors seem to get the ordering of irq_set_chained_handler()
> and irq_set_handler_data() wrong - ordering the former before the
> latter.  This opens a race window where, if there is an interrupt
> pending, the handler will be called between these two calls,
> potentially resulting in an oops.
> 
> Provide a single interface to set both of these together, especially
> as that's commonly what is required.
> 
> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
> ---
> It probably makes sense to convert everything over to this new
> registration function, and kill all users of irq_set_chained_handler()
> to prevent this problem recurring.  Thoughts?

Yes. Classic coccinelle problem. Here is the semantic patch:

@@
expression E1, E2, E3;
@@
-irq_set_chained_handler(E1, E3);
...
-irq_set_handler_data(E1, E2);
+irq_set_chained_handler_and_data(E1, E3, E2);

This finds and corrects all instances which get it wrong:

arch:
 arm/common/locomo.c                   |    3 +--
 arm/common/sa1111.c                   |    3 +--
 arm/mach-gemini/gpio.c                |    4 ++--
 avr32/mach-at32ap/extint.c            |    3 +--
 m68k/mac/psc.c                        |   12 ++++--------
 mips/ath25/ar2315.c                   |    4 ++--
 mips/ath25/ar5312.c                   |    4 ++--
 mips/pci/pci-ar2315.c                 |    4 ++--
 mips/ralink/irq.c                     |    3 +--
 sh/intc/core.c                        |    5 +++--

drivers:
 dma/ipu/ipu_irq.c                     |    6 ++----
 gpio/gpio-bcm-kona.c                  |    5 +++--
 gpio/gpio-davinci.c                   |   10 ++--------
 gpio/gpio-dwapb.c                     |    4 ++--
 gpio/gpio-msic.c                      |    3 +--
 gpio/gpio-mxc.c                       |   10 +++++-----
 gpio/gpio-mxs.c                       |    4 ++--
 gpio/gpio-tegra.c                     |    4 ++--
 gpu/ipu-v3/ipu-common.c               |   13 +++++--------
 irqchip/irq-keystone.c                |    4 ++--
 irqchip/spear-shirq.c                 |    3 +--
 mfd/pm8921-core.c                     |    6 ++----
 mfd/t7l66xb.c                         |    3 +--
 mfd/tc6393xb.c                        |    3 +--
 pci/host/pci-keystone.c               |    7 +++----
 pinctrl/mediatek/pinctrl-mtk-common.c |    3 +--
 pinctrl/pinctrl-adi2.c                |    4 ++--
 pinctrl/pinctrl-st.c                  |    4 ++--
 pinctrl/samsung/pinctrl-exynos.c      |    4 ++--
 pinctrl/samsung/pinctrl-s3c24xx.c     |    3 +--
 pinctrl/samsung/pinctrl-s3c64xx.c     |    8 ++++----
 pinctrl/sunxi/pinctrl-sunxi.c         |    6 +++---
 spmi/spmi-pmic-arb.c                  |    6 ++----
 33 files changed, 70 insertions(+), 98 deletions(-)

If we revert the search pattern we get the ones which got it right:

@@
expression E1, E2, E3;
@@
-irq_set_handler_data(E1, E2);
...
-irq_set_chained_handler(E1, E3);
+irq_set_chained_handler_and_data(E1, E3, E2);

That handles another bunch and leaves us with 135 instances of
irq_set_chained_handler() which do not set handler data. So its
trivial to change them to

 irq_set_chained_handler_and_data(irq, handler, NULL);

and then remove irq_set_chained_handler()

If thats ok for you, then i apply the lot you sent and run the cocci
scripts right at rc1. I have another set of transformations in that
area pending.

Thanks,

	tglx

^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH 1/9] irq: add irq_set_chained_handler_and_data()
  2015-06-17 14:10 ` [PATCH 1/9] irq: add irq_set_chained_handler_and_data() Thomas Gleixner
@ 2015-06-17 19:38   ` Russell King - ARM Linux
  0 siblings, 0 replies; 5+ messages in thread
From: Russell King - ARM Linux @ 2015-06-17 19:38 UTC (permalink / raw
  To: linux-arm-kernel

On Wed, Jun 17, 2015 at 04:10:02PM +0200, Thomas Gleixner wrote:
> On Tue, 16 Jun 2015, Russell King wrote:
> 
> > Driver authors seem to get the ordering of irq_set_chained_handler()
> > and irq_set_handler_data() wrong - ordering the former before the
> > latter.  This opens a race window where, if there is an interrupt
> > pending, the handler will be called between these two calls,
> > potentially resulting in an oops.
> > 
> > Provide a single interface to set both of these together, especially
> > as that's commonly what is required.
> > 
> > Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
> > ---
> > It probably makes sense to convert everything over to this new
> > registration function, and kill all users of irq_set_chained_handler()
> > to prevent this problem recurring.  Thoughts?
> 
> Yes. Classic coccinelle problem. Here is the semantic patch:
> 
> @@
> expression E1, E2, E3;
> @@
> -irq_set_chained_handler(E1, E3);
> ...
> -irq_set_handler_data(E1, E2);
> +irq_set_chained_handler_and_data(E1, E3, E2);
> 
> This finds and corrects all instances which get it wrong:
> 
> arch:
>  arm/common/locomo.c                   |    3 +--
>  arm/common/sa1111.c                   |    3 +--
>  arm/mach-gemini/gpio.c                |    4 ++--
>  avr32/mach-at32ap/extint.c            |    3 +--
>  m68k/mac/psc.c                        |   12 ++++--------
>  mips/ath25/ar2315.c                   |    4 ++--
>  mips/ath25/ar5312.c                   |    4 ++--
>  mips/pci/pci-ar2315.c                 |    4 ++--
>  mips/ralink/irq.c                     |    3 +--
>  sh/intc/core.c                        |    5 +++--
> 
> drivers:
>  dma/ipu/ipu_irq.c                     |    6 ++----
>  gpio/gpio-bcm-kona.c                  |    5 +++--
>  gpio/gpio-davinci.c                   |   10 ++--------
>  gpio/gpio-dwapb.c                     |    4 ++--
>  gpio/gpio-msic.c                      |    3 +--
>  gpio/gpio-mxc.c                       |   10 +++++-----
>  gpio/gpio-mxs.c                       |    4 ++--
>  gpio/gpio-tegra.c                     |    4 ++--
>  gpu/ipu-v3/ipu-common.c               |   13 +++++--------
>  irqchip/irq-keystone.c                |    4 ++--
>  irqchip/spear-shirq.c                 |    3 +--
>  mfd/pm8921-core.c                     |    6 ++----
>  mfd/t7l66xb.c                         |    3 +--
>  mfd/tc6393xb.c                        |    3 +--
>  pci/host/pci-keystone.c               |    7 +++----
>  pinctrl/mediatek/pinctrl-mtk-common.c |    3 +--
>  pinctrl/pinctrl-adi2.c                |    4 ++--
>  pinctrl/pinctrl-st.c                  |    4 ++--
>  pinctrl/samsung/pinctrl-exynos.c      |    4 ++--
>  pinctrl/samsung/pinctrl-s3c24xx.c     |    3 +--
>  pinctrl/samsung/pinctrl-s3c64xx.c     |    8 ++++----
>  pinctrl/sunxi/pinctrl-sunxi.c         |    6 +++---
>  spmi/spmi-pmic-arb.c                  |    6 ++----
>  33 files changed, 70 insertions(+), 98 deletions(-)
> 
> If we revert the search pattern we get the ones which got it right:
> 
> @@
> expression E1, E2, E3;
> @@
> -irq_set_handler_data(E1, E2);
> ...
> -irq_set_chained_handler(E1, E3);
> +irq_set_chained_handler_and_data(E1, E3, E2);
> 
> That handles another bunch and leaves us with 135 instances of
> irq_set_chained_handler() which do not set handler data. So its
> trivial to change them to
> 
>  irq_set_chained_handler_and_data(irq, handler, NULL);
> 
> and then remove irq_set_chained_handler()
> 
> If thats ok for you, then i apply the lot you sent and run the cocci
> scripts right at rc1. I have another set of transformations in that
> area pending.

Totally fine with that.

-- 
FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up
according to speedtest.net.

^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH] GPU: ipu: fix lockup caused by pending chained interrupts
  2015-06-16 22:29 ` [PATCH] GPU: ipu: fix lockup caused by pending chained interrupts Russell King
@ 2015-06-19 14:36   ` Philipp Zabel
  0 siblings, 0 replies; 5+ messages in thread
From: Philipp Zabel @ 2015-06-19 14:36 UTC (permalink / raw
  To: linux-arm-kernel

Am Dienstag, den 16.06.2015, 23:29 +0100 schrieb Russell King:
> Even with the oops fixed by a previous patch, the system still fails to
> kexec, due to a stuck chained interrupt locking the system.  We must
> disable the child interrupts prior to setting up the irq chip to ensure
> we don't get stuck here.
> 
> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Applied, thank you.

> Maybe this is all that's really needed... would also be nice if this
> path had an etry in MAINTAINERS...

I'll send a patch to add it to the imx-drm driver section.

regards
Philipp

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2015-06-19 14:36 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
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2015-06-16 22:06 [PATCH 1/9] irq: add irq_set_chained_handler_and_data() Russell King
2015-06-16 22:29 ` [PATCH] GPU: ipu: fix lockup caused by pending chained interrupts Russell King
2015-06-19 14:36   ` Philipp Zabel
2015-06-17 14:10 ` [PATCH 1/9] irq: add irq_set_chained_handler_and_data() Thomas Gleixner
2015-06-17 19:38   ` Russell King - ARM Linux

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