diff options
| author | Marc Zyngier <maz@kernel.org> | 2020-10-05 17:02:17 +0300 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2020-10-07 12:47:41 +0300 |
| commit | 8b81edd80baf12d64420daff1759380aa9a14998 (patch) | |
| tree | 9d168af1a0db163e24a5f79afd4c88f172dc1831 /drivers/gpio/gpio-pca953x.c | |
| parent | 47e538d86d5776ac8152146c3ed3d22326243190 (diff) | |
| download | linux-8b81edd80baf12d64420daff1759380aa9a14998.tar.xz | |
gpio: pca953x: Survive spurious interrupts
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 <maz@kernel.org>
Link: https://lore.kernel.org/r/20201005140217.1390851-1-maz@kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/gpio/gpio-pca953x.c')
| -rw-r--r-- | drivers/gpio/gpio-pca953x.c | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c index fb61f2fc6ed7..c2d6121c48c9 100644 --- a/drivers/gpio/gpio-pca953x.c +++ b/drivers/gpio/gpio-pca953x.c @@ -824,8 +824,21 @@ 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); } |