On Tue, 13 Jul 2021 23:31:28 +0200 Pavel Machek <pavel@xxxxxxx> wrote: > Hi! > > > commit 7cd04c863f9e1655d607705455e7714f24451984 upstream. > > > > Allocating an IRQ is conditional to the IRQ existence, but freeing it > > was not. If no IRQ was allocate, the driver would still try to free > > IRQ 0. Add the missing checks. > > > > This fixes the following trace when the driver is removed: > > > > [ 100.667788] Trying to free already-free IRQ 0 > > AFAICT this will need more fixing, because IRQ == 0 is a valid > IRQ. NO_IRQ (aka -1) should be safe to use for "no irq assigned". > I thought we had long put this to bed. IRQ == 0 is not a valid irq number. If there is an error in parsing DT (e.g. no irq specified) it returns 0 not NO_IRQ. Naturally irq chips can have a 0, but that's pre translation to virtual IRQ space. Many years ago, ARM did have 0 as as valid IRQ, but that got cleaned up to make it easier to do generic code like this. Jonathan > Best regards, > Pavel > > > +++ b/drivers/iio/light/tcs3472.c > > @@ -531,7 +531,8 @@ static int tcs3472_probe(struct i2c_clie > > return 0; > > > > free_irq: > > - free_irq(client->irq, indio_dev); > > + if (client->irq) > > + free_irq(client->irq, indio_dev); > > buffer_cleanup: > > iio_triggered_buffer_cleanup(indio_dev); > > return ret; >
