diff options
| author | Schspa Shi <schspa@gmail.com> | 2022-04-19 09:28:10 +0800 |
|---|---|---|
| committer | Bartosz Golaszewski <brgl@bgdev.pl> | 2022-04-25 12:10:02 +0200 |
| commit | 3c938cc5cebcbd2291fe97f523c0705a2c24c77d (patch) | |
| tree | 52e5e975be7a8a43275a4c7d897b4994c564ea55 /include/linux/gpio/driver.h | |
| parent | 4f3e79b36d7fdbc3315efe5612a01800931fa25d (diff) | |
| download | linux-next-3c938cc5cebcbd2291fe97f523c0705a2c24c77d.tar.gz | |
gpio: use raw spinlock for gpio chip shadowed data
In case of PREEMPT_RT, there is a raw_spinlock -> spinlock dependency
as the lockdep report shows.
__irq_set_handler
irq_get_desc_buslock
__irq_get_desc_lock
raw_spin_lock_irqsave(&desc->lock, *flags); // raw spinlock get here
__irq_do_set_handler
mask_ack_irq
dwapb_irq_ack
spin_lock_irqsave(&gc->bgpio_lock, flags); // sleep able spinlock
irq_put_desc_busunlock
Replace with a raw lock to avoid BUGs. This lock is only used to access
registers, and It's safe to replace with the raw lock without bad
influence.
[ 15.090359][ T1] =============================
[ 15.090365][ T1] [ BUG: Invalid wait context ]
[ 15.090373][ T1] 5.10.59-rt52-00983-g186a6841c682-dirty #3 Not tainted
[ 15.090386][ T1] -----------------------------
[ 15.090392][ T1] swapper/0/1 is trying to lock:
[ 15.090402][ T1] 70ff00018507c188 (&gc->bgpio_lock){....}-{3:3}, at: _raw_spin_lock_irqsave+0x1c/0x28
[ 15.090470][ T1] other info that might help us debug this:
[ 15.090477][ T1] context-{5:5}
[ 15.090485][ T1] 3 locks held by swapper/0/1:
[ 15.090497][ T1] #0: c2ff0001816de1a0 (&dev->mutex){....}-{4:4}, at: __device_driver_lock+0x98/0x104
[ 15.090553][ T1] #1: ffff90001485b4b8 (irq_domain_mutex){+.+.}-{4:4}, at: irq_domain_associate+0xbc/0x6d4
[ 15.090606][ T1] #2: 4bff000185d7a8e0 (lock_class){....}-{2:2}, at: _raw_spin_lock_irqsave+0x1c/0x28
[ 15.090654][ T1] stack backtrace:
[ 15.090661][ T1] CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.10.59-rt52-00983-g186a6841c682-dirty #3
[ 15.090682][ T1] Hardware name: Horizon Robotics Journey 5 DVB (DT)
[ 15.090692][ T1] Call trace:
......
[ 15.090811][ T1] _raw_spin_lock_irqsave+0x1c/0x28
[ 15.090828][ T1] dwapb_irq_ack+0xb4/0x300
[ 15.090846][ T1] __irq_do_set_handler+0x494/0xb2c
[ 15.090864][ T1] __irq_set_handler+0x74/0x114
[ 15.090881][ T1] irq_set_chip_and_handler_name+0x44/0x58
[ 15.090900][ T1] gpiochip_irq_map+0x210/0x644
Signed-off-by: Schspa Shi <schspa@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Doug Berger <opendmb@gmail.com>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Diffstat (limited to 'include/linux/gpio/driver.h')
| -rw-r--r-- | include/linux/gpio/driver.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index 98c93510640e..991d374dcf71 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -436,7 +436,7 @@ struct gpio_chip { void __iomem *reg_dir_in; bool bgpio_dir_unreadable; int bgpio_bits; - spinlock_t bgpio_lock; + raw_spinlock_t bgpio_lock; unsigned long bgpio_data; unsigned long bgpio_dir; #endif /* CONFIG_GPIO_GENERIC */ |