4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Christophe Leroy <christophe.leroy@xxxxxx> commit 6f553912eedafae13ff20b322a65e471fe7f5236 upstream. of_mm_gpiochip_add_data() generates an oops for NULL pointer dereference. of_mm_gpiochip_add_data() calls mm_gc->save_regs() before setting the data, therefore ->save_regs() cannot use gpiochip_get_data() Fixes: 937daafca774 ("powerpc: simple-gpio: use gpiochip data pointer") Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx> Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/sysdev/simple_gpio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/arch/powerpc/sysdev/simple_gpio.c +++ b/arch/powerpc/sysdev/simple_gpio.c @@ -75,7 +75,8 @@ static int u8_gpio_dir_out(struct gpio_c static void u8_gpio_save_regs(struct of_mm_gpio_chip *mm_gc) { - struct u8_gpio_chip *u8_gc = gpiochip_get_data(&mm_gc->gc); + struct u8_gpio_chip *u8_gc = + container_of(mm_gc, struct u8_gpio_chip, mm_gc); u8_gc->data = in_8(mm_gc->regs); }