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From: Robin Murphy <robin.murphy-5wv7dgnIgG8@public.gmane.org>
To: joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org
Cc: heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org,
	maz-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org,
	Vasily Khoruzhick
	<anarsoul-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>,
	linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
	iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org,
	linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
Subject: [PATCH] iommu/rockchip: Don't provoke WARN for harmless IRQs
Date: Mon, 11 Nov 2019 18:55:18 +0000	[thread overview]
Message-ID: <82cba203551939399d219e4cb6c602315fd0c410.1573498518.git.robin.murphy@arm.com> (raw)

Although we don't generally expect IRQs to fire for a suspended IOMMU,
there are certain situations (particularly with debug options) where
we might legitimately end up with the pm_runtime_get_if_in_use() call
from rk_iommu_irq() returning 0. Since this doesn't represent an actual
error, follow the other parts of the driver and save the WARN_ON()
condition for a genuine negative value. Even if we do have spurious
IRQs due to a wedged VOP asserting the shared line, it's not this
driver's job to try to second-guess the IRQ core to warn about that.

Reported-by: Vasily Khoruzhick <anarsoul-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Signed-off-by: Robin Murphy <robin.murphy-5wv7dgnIgG8@public.gmane.org>
---
 drivers/iommu/rockchip-iommu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index 4dcbf68dfda4..bd7e9b1e40ac 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -527,7 +527,7 @@ static irqreturn_t rk_iommu_irq(int irq, void *dev_id)
 	int i, err;
 
 	err = pm_runtime_get_if_in_use(iommu->dev);
-	if (WARN_ON_ONCE(err <= 0))
+	if (!err || WARN_ON_ONCE(err < 0))
 		return ret;
 
 	if (WARN_ON(clk_bulk_enable(iommu->num_clocks, iommu->clocks)))
-- 
2.20.1

WARNING: multiple messages have this Message-ID (diff)
From: Robin Murphy <robin.murphy@arm.com>
To: joro@8bytes.org
Cc: heiko@sntech.de, maz@kernel.org,
	Vasily Khoruzhick <anarsoul@gmail.com>,
	linux-rockchip@lists.infradead.org,
	iommu@lists.linux-foundation.org,
	linux-arm-kernel@lists.infradead.org
Subject: [PATCH] iommu/rockchip: Don't provoke WARN for harmless IRQs
Date: Mon, 11 Nov 2019 18:55:18 +0000	[thread overview]
Message-ID: <82cba203551939399d219e4cb6c602315fd0c410.1573498518.git.robin.murphy@arm.com> (raw)

Although we don't generally expect IRQs to fire for a suspended IOMMU,
there are certain situations (particularly with debug options) where
we might legitimately end up with the pm_runtime_get_if_in_use() call
from rk_iommu_irq() returning 0. Since this doesn't represent an actual
error, follow the other parts of the driver and save the WARN_ON()
condition for a genuine negative value. Even if we do have spurious
IRQs due to a wedged VOP asserting the shared line, it's not this
driver's job to try to second-guess the IRQ core to warn about that.

Reported-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
 drivers/iommu/rockchip-iommu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index 4dcbf68dfda4..bd7e9b1e40ac 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -527,7 +527,7 @@ static irqreturn_t rk_iommu_irq(int irq, void *dev_id)
 	int i, err;
 
 	err = pm_runtime_get_if_in_use(iommu->dev);
-	if (WARN_ON_ONCE(err <= 0))
+	if (!err || WARN_ON_ONCE(err < 0))
 		return ret;
 
 	if (WARN_ON(clk_bulk_enable(iommu->num_clocks, iommu->clocks)))
-- 
2.20.1

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

WARNING: multiple messages have this Message-ID (diff)
From: Robin Murphy <robin.murphy@arm.com>
To: joro@8bytes.org
Cc: heiko@sntech.de, maz@kernel.org,
	linux-rockchip@lists.infradead.org,
	iommu@lists.linux-foundation.org,
	linux-arm-kernel@lists.infradead.org
Subject: [PATCH] iommu/rockchip: Don't provoke WARN for harmless IRQs
Date: Mon, 11 Nov 2019 18:55:18 +0000	[thread overview]
Message-ID: <82cba203551939399d219e4cb6c602315fd0c410.1573498518.git.robin.murphy@arm.com> (raw)

Although we don't generally expect IRQs to fire for a suspended IOMMU,
there are certain situations (particularly with debug options) where
we might legitimately end up with the pm_runtime_get_if_in_use() call
from rk_iommu_irq() returning 0. Since this doesn't represent an actual
error, follow the other parts of the driver and save the WARN_ON()
condition for a genuine negative value. Even if we do have spurious
IRQs due to a wedged VOP asserting the shared line, it's not this
driver's job to try to second-guess the IRQ core to warn about that.

Reported-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
 drivers/iommu/rockchip-iommu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index 4dcbf68dfda4..bd7e9b1e40ac 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -527,7 +527,7 @@ static irqreturn_t rk_iommu_irq(int irq, void *dev_id)
 	int i, err;
 
 	err = pm_runtime_get_if_in_use(iommu->dev);
-	if (WARN_ON_ONCE(err <= 0))
+	if (!err || WARN_ON_ONCE(err < 0))
 		return ret;
 
 	if (WARN_ON(clk_bulk_enable(iommu->num_clocks, iommu->clocks)))
-- 
2.20.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

             reply	other threads:[~2019-11-11 18:55 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-11 18:55 Robin Murphy [this message]
2019-11-11 18:55 ` [PATCH] iommu/rockchip: Don't provoke WARN for harmless IRQs Robin Murphy
2019-11-11 18:55 ` Robin Murphy
     [not found] ` <82cba203551939399d219e4cb6c602315fd0c410.1573498518.git.robin.murphy-5wv7dgnIgG8@public.gmane.org>
2019-11-12 11:31   ` Marc Zyngier
2019-11-12 11:31     ` Marc Zyngier
2019-11-12 11:31     ` Marc Zyngier
2019-11-12 16:08   ` Joerg Roedel
2019-11-12 16:08     ` Joerg Roedel
2019-11-12 16:08     ` Joerg Roedel

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