patch "iio: pressure: bmp280: fix runtime suspend/resume crash" added to staging-linus

patch "iio: pressure: bmp280: fix runtime suspend/resume crash" added to staging-linus

[gregkh]

This is a note to let you know that I've just added the patch titled

    iio: pressure: bmp280: fix runtime suspend/resume crash

to my staging git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


>From 31f453eac56bdc41f434126bc2d5933b9fb720ec Mon Sep 17 00:00:00 2001
From: Linus Walleij <linus.walleij@linaro.org>
Date: Wed, 27 Jul 2016 22:32:58 +0200
Subject: iio: pressure: bmp280: fix runtime suspend/resume crash

In commit 3d838118c6aa ("iio: pressure: bmp280: add power management")

For some reason the code in the runtime suspend/resume hooks
got wrong (I suspect in the ambition to cut down boilerplate)
and it seems it was tested without CONFIG_PM and crashes like
so for me:

Unable to handle kernel NULL pointer dereference at virtual address 0000000c
pgd = c0204000
[0000000c] *pgd=00000000
Internal error: Oops: 5 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 1 PID: 89 Comm: kworker/1:2 Not tainted
  4.7.0-03348-g90dc3680458a-dirty #99
Hardware name: Generic DT based system
Workqueue: pm pm_runtime_work
task: df3c6300 ti: dec8a000 task.ti: dec8a000
PC is at regulator_disable+0x0/0x6c
LR is at bmp280_runtime_suspend+0x3c/0xa4

Dereferencing the BMP280 state container properly fixes the problem,
sorry for screwing up.

Fixes: 3d838118c6aa ("iio: pressure: bmp280: add power management")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
---
 drivers/iio/pressure/bmp280-core.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
index 94e27b2600f3..e5a533cbd53f 100644
--- a/drivers/iio/pressure/bmp280-core.c
+++ b/drivers/iio/pressure/bmp280-core.c
@@ -1079,7 +1079,8 @@ EXPORT_SYMBOL(bmp280_common_remove);
 #ifdef CONFIG_PM
 static int bmp280_runtime_suspend(struct device *dev)
 {
-	struct bmp280_data *data = dev_get_drvdata(dev);
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct bmp280_data *data = iio_priv(indio_dev);
 	int ret;
 
 	ret = regulator_disable(data->vdda);
@@ -1090,7 +1091,8 @@ static int bmp280_runtime_suspend(struct device *dev)
 
 static int bmp280_runtime_resume(struct device *dev)
 {
-	struct bmp280_data *data = dev_get_drvdata(dev);
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct bmp280_data *data = iio_priv(indio_dev);
 	int ret;
 
 	ret = regulator_enable(data->vddd);
-- 
2.9.3