drivers/pinctrl/bcm/pinctrl-bcm2835.c:413:14: warning: variable 'group' is used uninitialized whenever 'for' loop exits because its condition is false
From: kernel test robot
Date: Thu Dec 09 2021 - 00:32:27 EST
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 2a987e65025e2b79c6d453b78cb5985ac6e5eb26
commit: 4434f4c50345c84373b7117b5c827a88870f9d36 pinctrl: bcm2835: Allow building driver as a module
date: 6 weeks ago
config: mips-randconfig-r001-20211209 (https://download.01.org/0day-ci/archive/20211209/202112091309.HCSKbMQS-lkp@xxxxxxxxx/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 097a1cb1d5ebb3a0ec4bcaed8ba3ff6a8e33c00a)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install mips cross compiling tool for clang build
# apt-get install binutils-mips-linux-gnu
# https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=4434f4c50345c84373b7117b5c827a88870f9d36
git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout 4434f4c50345c84373b7117b5c827a88870f9d36
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash drivers/pinctrl/bcm/
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>
All warnings (new ones prefixed by >>):
>> drivers/pinctrl/bcm/pinctrl-bcm2835.c:413:14: warning: variable 'group' is used uninitialized whenever 'for' loop exits because its condition is false [-Wsometimes-uninitialized]
for (i = 0; i < BCM2835_NUM_IRQS; i++) {
^~~~~~~~~~~~~~~~~~~~
drivers/pinctrl/bcm/pinctrl-bcm2835.c:424:10: note: uninitialized use occurs here
switch (group) {
^~~~~
drivers/pinctrl/bcm/pinctrl-bcm2835.c:413:14: note: remove the condition if it is always true
for (i = 0; i < BCM2835_NUM_IRQS; i++) {
^~~~~~~~~~~~~~~~~~~~
drivers/pinctrl/bcm/pinctrl-bcm2835.c:410:11: note: initialize the variable 'group' to silence this warning
int group;
^
= 0
1 warning generated.
vim +413 drivers/pinctrl/bcm/pinctrl-bcm2835.c
00445b5d5866c7 drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 403
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 404 static void bcm2835_gpio_irq_handler(struct irq_desc *desc)
00445b5d5866c7 drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 405 {
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 406 struct gpio_chip *chip = irq_desc_get_handler_data(desc);
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 407 struct bcm2835_pinctrl *pc = gpiochip_get_data(chip);
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 408 struct irq_chip *host_chip = irq_desc_get_chip(desc);
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 409 int irq = irq_desc_get_irq(desc);
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 410 int group;
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 411 int i;
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 412
73345a18d464b1 drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2019-08-12 @413 for (i = 0; i < BCM2835_NUM_IRQS; i++) {
73345a18d464b1 drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2019-08-12 414 if (chip->irq.parents[i] == irq) {
0d885e9da176ad drivers/pinctrl/bcm/pinctrl-bcm2835.c Thierry Reding 2017-07-20 415 group = i;
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 416 break;
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 417 }
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 418 }
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 419 /* This should not happen, every IRQ has a bank */
29d45a642d4ea8 drivers/pinctrl/bcm/pinctrl-bcm2835.c Jason Wang 2021-06-24 420 BUG_ON(i == BCM2835_NUM_IRQS);
00445b5d5866c7 drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 421
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 422 chained_irq_enter(host_chip, desc);
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 423
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 424 switch (group) {
00445b5d5866c7 drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 425 case 0: /* IRQ0 covers GPIOs 0-27 */
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 426 bcm2835_gpio_irq_handle_bank(pc, 0, 0x0fffffff);
00445b5d5866c7 drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 427 break;
00445b5d5866c7 drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 428 case 1: /* IRQ1 covers GPIOs 28-45 */
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 429 bcm2835_gpio_irq_handle_bank(pc, 0, 0xf0000000);
00445b5d5866c7 drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 430 bcm2835_gpio_irq_handle_bank(pc, 1, 0x00003fff);
00445b5d5866c7 drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 431 break;
b1d84a3d0a26c5 drivers/pinctrl/bcm/pinctrl-bcm2835.c Stefan Wahren 2020-02-08 432 case 2: /* IRQ2 covers GPIOs 46-57 */
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 433 bcm2835_gpio_irq_handle_bank(pc, 1, 0x003fc000);
00445b5d5866c7 drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 434 break;
00445b5d5866c7 drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 435 }
00445b5d5866c7 drivers/pinctrl/bcm/pinctrl-bcm2835.c Phil Elwell 2015-02-24 436
85ae9e512f437c drivers/pinctrl/bcm/pinctrl-bcm2835.c Linus Walleij 2016-11-14 437 chained_irq_exit(host_chip, desc);
e1b2dc70cd5b00 drivers/pinctrl/pinctrl-bcm2835.c Simon Arlott 2012-09-27 438 }
e1b2dc70cd5b00 drivers/pinctrl/pinctrl-bcm2835.c Simon Arlott 2012-09-27 439
:::::: The code at line 413 was first introduced by commit
:::::: 73345a18d464b1b945b29f54f630ace6873344e2 pinctrl: bcm2835: Pass irqchip when adding gpiochip
:::::: TO: Linus Walleij <linus.walleij@xxxxxxxxxx>
:::::: CC: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
0-DAY CI Kernel Test Service, Intel Corporation
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