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gpiolib: cdev: Set lineevent_state::irq after IRQ register successfully

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When running gpio test on nxp-ls1028 platform with below command
gpiomon --num-events=3 --rising-edge gpiochip1 25
There will be a warning trace as below:
Call trace:
free_irq+0x204/0x360
lineevent_free+0x64/0x70
gpio_ioctl+0x598/0x6a0
__arm64_sys_ioctl+0xb4/0x100
invoke_syscall+0x5c/0x130
......
el0t_64_sync+0x1a0/0x1a4
The reason of this issue is that calling request_threaded_irq()
function failed, and then lineevent_free() is invoked to release
the resource. Since the lineevent_state::irq was already set, so
the subsequent invocation of free_irq() would trigger the above
warning call trace. To fix this issue, set the lineevent_state::irq
after the IRQ register successfully.

Fixes: 4682427241 ("gpiolib: cdev: refactor lineevent cleanup into lineevent_free")
Cc: stable@vger.kernel.org
Signed-off-by: Meng Li <Meng.Li@windriver.com>
Reviewed-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
This commit is contained in:
Meng Li 2022-09-21 11:20:20 +08:00 committed by Bartosz Golaszewski
parent 21a9acc162
commit 69bef19d6b
1 changed files with 3 additions and 2 deletions
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5
drivers/gpio/gpiolib-cdev.c
View file

@ -1986,7 +1986,6 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
ret = -ENODEV;
goto out_free_le;
}
le->irq = irq;
if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
@ -2000,7 +1999,7 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
init_waitqueue_head(&le->wait);
/* Request a thread to read the events */
ret = request_threaded_irq(le->irq,
ret = request_threaded_irq(irq,
lineevent_irq_handler,
lineevent_irq_thread,
irqflags,
@ -2009,6 +2008,8 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
if (ret)
goto out_free_le;
le->irq = irq;
fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
if (fd < 0) {
ret = fd;