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i2c: core: Disable client irq on reboot/shutdown

Message ID 20210604212752.3547301-1-swboyd@chromium.org
State New
Headers show
Series i2c: core: Disable client irq on reboot/shutdown | expand

Commit Message

Stephen Boyd June 4, 2021, 9:27 p.m. UTC 
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>

If an i2c client receives an interrupt during reboot or shutdown it may
be too late to service it by making an i2c transaction on the bus
because the i2c controller has already been shutdown. This can lead to
system hangs if the i2c controller tries to make a transfer that is
doomed to fail because the access to the i2c pins is already shut down,
or an iommu translation has been torn down so i2c controller register
access doesn't work.

Let's simply disable the irq if there isn't a shutdown callback for an
i2c client when there is an irq associated with the device. This will
make sure that irqs don't come in later than the time that we can handle
it. We don't do this if the i2c client device already has a shutdown
callback because presumably they're doing the right thing and quieting
the device so irqs don't come in after the shutdown callback returns.

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
[swboyd@chromium.org: Dropped newline, added commit text]
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
---

Dmitry, please add Signed-off-by

This supersedes https://lore.kernel.org/r/20210510220012.2003285-1-swboyd@chromium.org

 drivers/i2c/i2c-core-base.c | 2 ++
 1 file changed, 2 insertions(+)


base-commit: 8124c8a6b35386f73523d27eacb71b5364a68c4c

Comments

Stephen Boyd June 4, 2021, 11:09 p.m. UTC | #1 
Quoting kernel test robot (2021-06-04 16:01:32)
> Hi Stephen,
>
> I love your patch! Yet something to improve:
>
> [auto build test ERROR on 8124c8a6b35386f73523d27eacb71b5364a68c4c]
>
> url:    https://github.com/0day-ci/linux/commits/Stephen-Boyd/i2c-core-Disable-client-irq-on-reboot-shutdown/20210605-052848
> base:   8124c8a6b35386f73523d27eacb71b5364a68c4c
> config: nios2-randconfig-s031-20210604 (attached as .config)
> compiler: nios2-linux-gcc (GCC) 9.3.0
> reproduce:
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # apt-get install sparse
>         # sparse version: v0.6.3-341-g8af24329-dirty
>         # https://github.com/0day-ci/linux/commit/2fb1417bc9d82a335db5ed8a1446be74bffae440
>         git remote add linux-review https://github.com/0day-ci/linux
>         git fetch --no-tags linux-review Stephen-Boyd/i2c-core-Disable-client-irq-on-reboot-shutdown/20210605-052848
>         git checkout 2fb1417bc9d82a335db5ed8a1446be74bffae440
>         # save the attached .config to linux build tree
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' W=1 ARCH=nios2
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
>
> All errors (new ones prefixed by >>):
>
>    drivers/i2c/i2c-core-base.c: In function 'i2c_device_shutdown':
> >> drivers/i2c/i2c-core-base.c:631:3: error: implicit declaration of function 'disable_irq'; did you mean 'disable_srat'? [-Werror=implicit-function-declaration]

Must need interrupt.h, which I must have got implicitly somehow.

>      631 |   disable_irq(client->irq);
>          |   ^~~~~~~~~~~
>          |   disable_srat
diff mbox series

Patch

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 5a97e4a02fa2..7ea5d7cc5974 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -627,6 +627,8 @@  static void i2c_device_shutdown(struct device *dev)
 	driver = to_i2c_driver(dev->driver);
 	if (driver->shutdown)
 		driver->shutdown(client);
+	else if (client->irq > 0)
+		disable_irq(client->irq);
 }
 
 static void i2c_client_dev_release(struct device *dev)