diff options
| author | Bamvor Jian Zhang <bamvor.zhangjian@linaro.org> | 2016-02-20 13:13:19 +0800 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2016-02-20 12:48:34 +0100 |
| commit | bd203bd56d12401398faa7428c81c1d76c91611e (patch) | |
| tree | a93c70f35ae55e206f0d12b088bfe8d8830a7940 /drivers | |
| parent | 3e089d9f55acfe9edd8a71d19cfc3129ab3a37f8 (diff) | |
| download | linux-bd203bd56d12401398faa7428c81c1d76c91611e.tar.bz2 | |
gpiolib: fix crash when gpiochip removed
Commit cb464a88e1ed ("gpio: make the gpiochip a real device") call
gpiochip_sysfs_unregister after the gpiochip is empty. It lead to the
following crash:
[ 163.503994] Unable to handle kernel NULL pointer dereference at virtual address 0000007c
[...]
[ 163.525394] [<ffffffc0003719a0>] gpiochip_sysfs_unregister+0x44/0xa4
[ 163.525611] [<ffffffc00036f6a0>] gpiochip_remove+0x24/0x154
[ 163.525861] [<ffffffbffc00f0a4>] mockup_gpio_remove+0x38/0x64 [gpio_mockup]
[ 163.526101] [<ffffffc00042b4b4>] platform_drv_remove+0x24/0x64
[ 163.526313] [<ffffffc000429cc8>] __device_release_driver+0x7c/0xfc
[ 163.526525] [<ffffffc000429e54>] driver_detach+0xbc/0xc0
[ 163.526700] [<ffffffc000429014>] bus_remove_driver+0x58/0xac
[ 163.526883] [<ffffffc00042a4cc>] driver_unregister+0x2c/0x4c
[ 163.527067] [<ffffffc00042b5c0>] platform_driver_unregister+0x10/0x18
[ 163.527284] [<ffffffbffc00f340>] mock_device_exit+0x10/0x38 [gpio_mockup]
[ 163.527593] [<ffffffc00011cefc>] SyS_delete_module+0x1b8/0x1fc
[ 163.527799] [<ffffffc000085d8c>] __sys_trace_return+0x0/0x4
[ 163.528049] Code: 940d74b4 f9019abf aa1303e0 940d7439 (7940fac0)
[ 163.536273] ---[ end trace 3d1329be504af609 ]---
This patch fix this by changing the code back.
Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gpio/gpiolib.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 3580c0de9d5a..b81646982375 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -684,11 +684,10 @@ void gpiochip_remove(struct gpio_chip *chip) unsigned i; bool requested = false; - /* Numb the device, cancelling all outstanding operations */ - gdev->chip = NULL; - /* FIXME: should the legacy sysfs handling be moved to gpio_device? */ gpiochip_sysfs_unregister(gdev); + /* Numb the device, cancelling all outstanding operations */ + gdev->chip = NULL; gpiochip_irqchip_remove(chip); acpi_gpiochip_remove(chip); gpiochip_remove_pin_ranges(chip); |