6.6-stable review patch. If anyone has any objections, please let me know.
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From: Fabrice Gasnier fabrice.gasnier@foss.st.com
commit f4a8f561d08e39f7833d4a278ebfb12a41eef15f upstream.
When enabling PREEMPT_RT, the gpio_keys_irq_timer() callback runs in hard irq context, but the input_event() takes a spin_lock, which isn't allowed there as it is converted to a rt_spin_lock().
[ 4054.289999] BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 [ 4054.290028] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/0 ... [ 4054.290195] __might_resched+0x13c/0x1f4 [ 4054.290209] rt_spin_lock+0x54/0x11c [ 4054.290219] input_event+0x48/0x80 [ 4054.290230] gpio_keys_irq_timer+0x4c/0x78 [ 4054.290243] __hrtimer_run_queues+0x1a4/0x438 [ 4054.290257] hrtimer_interrupt+0xe4/0x240 [ 4054.290269] arch_timer_handler_phys+0x2c/0x44 [ 4054.290283] handle_percpu_devid_irq+0x8c/0x14c [ 4054.290297] handle_irq_desc+0x40/0x58 [ 4054.290307] generic_handle_domain_irq+0x1c/0x28 [ 4054.290316] gic_handle_irq+0x44/0xcc
Considering the gpio_keys_irq_isr() can run in any context, e.g. it can be threaded, it seems there's no point in requesting the timer isr to run in hard irq context.
Relax the hrtimer not to use the hard context.
Fixes: 019002f20cb5 ("Input: gpio-keys - use hrtimer for release timer") Suggested-by: Sebastian Andrzej Siewior bigeasy@linutronix.de Signed-off-by: Fabrice Gasnier fabrice.gasnier@foss.st.com Signed-off-by: Gatien Chevallier gatien.chevallier@foss.st.com Link: https://lore.kernel.org/r/20250528-gpio_keys_preempt_rt-v2-1-3fc55a9c3619@fo... Cc: stable@vger.kernel.org Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com [ adjusted context ] Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/input/keyboard/gpio_keys.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/input/keyboard/gpio_keys.c +++ b/drivers/input/keyboard/gpio_keys.c @@ -495,7 +495,7 @@ static irqreturn_t gpio_keys_irq_isr(int if (bdata->release_delay) hrtimer_start(&bdata->release_timer, ms_to_ktime(bdata->release_delay), - HRTIMER_MODE_REL_HARD); + HRTIMER_MODE_REL); out: spin_unlock_irqrestore(&bdata->lock, flags); return IRQ_HANDLED; @@ -632,7 +632,7 @@ static int gpio_keys_setup_key(struct pl
bdata->release_delay = button->debounce_interval; hrtimer_init(&bdata->release_timer, - CLOCK_REALTIME, HRTIMER_MODE_REL_HARD); + CLOCK_REALTIME, HRTIMER_MODE_REL); bdata->release_timer.function = gpio_keys_irq_timer;
isr = gpio_keys_irq_isr;