From: Marc Zyngier <m...@kernel.org> [ Upstream commit 8b81edd80baf12d64420daff1759380aa9a14998 ]
The pca953x driver never checks the result of irq_find_mapping(), which returns 0 when no mapping is found. When a spurious interrupt is delivered (which can happen under obscure circumstances), the kernel explodes as it still tries to handle the error code as a real interrupt. Handle this particular case and warn on spurious interrupts. Signed-off-by: Marc Zyngier <m...@kernel.org> Link: https://lore.kernel.org/r/20201005140217.1390851-1-...@kernel.org Signed-off-by: Linus Walleij <linus.wall...@linaro.org> Signed-off-by: Sasha Levin <sas...@kernel.org> --- drivers/gpio/gpio-pca953x.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c index 11c3bbd105f11..1de182b85e4c4 100644 --- a/drivers/gpio/gpio-pca953x.c +++ b/drivers/gpio/gpio-pca953x.c @@ -821,8 +821,21 @@ static irqreturn_t pca953x_irq_handler(int irq, void *devid) ret = pca953x_irq_pending(chip, pending); mutex_unlock(&chip->i2c_lock); - for_each_set_bit(level, pending, gc->ngpio) - handle_nested_irq(irq_find_mapping(gc->irq.domain, level)); + if (ret) { + ret = 0; + + for_each_set_bit(level, pending, gc->ngpio) { + int nested_irq = irq_find_mapping(gc->irq.domain, level); + + if (unlikely(nested_irq <= 0)) { + dev_warn_ratelimited(gc->parent, "unmapped interrupt %d\n", level); + continue; + } + + handle_nested_irq(nested_irq); + ret = 1; + } + } return IRQ_RETVAL(ret); } -- 2.25.1
