4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Marc Zyngier <[email protected]> commit e8f241893dfbbebe2813c01eac54f263e6a5e59c upstream. irq_modify_status starts by clearing the trigger settings from irq_data before applying the new settings, but doesn't restore them, leaving them to IRQ_TYPE_NONE. That's pretty confusing to the potential request_irq() that could follow. Instead, snapshot the settings before clearing them, and restore them if the irq_modify_status() invocation was not changing the trigger. Fixes: 1e2a7d78499e ("irqdomain: Don't set type when mapping an IRQ") Reported-and-tested-by: jeffy <[email protected]> Signed-off-by: Marc Zyngier <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: Jon Hunter <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]> --- kernel/irq/chip.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -895,13 +895,15 @@ EXPORT_SYMBOL_GPL(irq_set_chip_and_handl void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set) { - unsigned long flags; + unsigned long flags, trigger, tmp; struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0); if (!desc) return; irq_settings_clr_and_set(desc, clr, set); + trigger = irqd_get_trigger_type(&desc->irq_data); + irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU | IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT); if (irq_settings_has_no_balance_set(desc)) @@ -913,7 +915,11 @@ void irq_modify_status(unsigned int irq, if (irq_settings_is_level(desc)) irqd_set(&desc->irq_data, IRQD_LEVEL); - irqd_set(&desc->irq_data, irq_settings_get_trigger_mask(desc)); + tmp = irq_settings_get_trigger_mask(desc); + if (tmp != IRQ_TYPE_NONE) + trigger = tmp; + + irqd_set(&desc->irq_data, trigger); irq_put_desc_unlock(desc, flags); }
