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

stable inclusion
from stable-v5.10.146
commit 657803b918e097e47d99d1489da83a603c36bcdd
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6D0VX

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=657803b918e097e47d99d1489da83a603c36bcdd

--------------------------------

commit 69bef19d upstream.

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: 46824272 ("gpiolib: cdev: refactor lineevent cleanup into lineevent_free")
Cc: stable@vger.kernel.org
Signed-off-by: NMeng Li <Meng.Li@windriver.com>
Reviewed-by: NKent Gibson <warthog618@gmail.com>
Signed-off-by: NBartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NJialin Zhang <zhangjialin11@huawei.com>
Reviewed-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/gpio/gpiolib-cdev.c

@@ -1769,7 +1769,6 @@ 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) ?
@@ -1783,7 +1782,7 @@ 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,
@@ -1792,6 +1791,8 @@ 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;