Messages in this thread |  | | Date | Tue, 29 Dec 2020 09:27:40 +0000 | From | Marc Zyngier <> | Subject | Re: [PATCH] irqchip/gic: add WARN_ON() to facilitate backtracking |
| |
Yejune,
On 2020-12-29 07:15, Yejune Deng wrote: > There is two function gic_of_init() and gic_of_init_child() called > gic_of_setup(),so add WARN_ON() to facilitate backtracking. > > Signed-off-by: Yejune Deng <yejune.deng@gmail.com> > --- > drivers/irqchip/irq-gic.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c > index b1d9c22..7c11705 100644 > --- a/drivers/irqchip/irq-gic.c > +++ b/drivers/irqchip/irq-gic.c > @@ -1380,7 +1380,7 @@ static bool gic_check_eoimode(struct device_node > *node, void __iomem **base) > > static int gic_of_setup(struct gic_chip_data *gic, struct device_node > *node) > { > - if (!gic || !node) > + if (WARN_ON(!gic || !node)) > return -EINVAL; > > gic->raw_dist_base = of_iomap(node, 0);
I don't immediately see what you gain with this. If you end-up here with NULL pointers, that either because:
- you have failed to allocate the GIC private data structure: but as it turns out, these allocations either cannot fail (gic_data[] is static), or the dynamic allocation in gic_of_init_child() is already checked.
- node is NULL: both paths already check for a NULL node, so that cannot fail either.
My conclusion is that these checks can never trigger, and we should be able to *remove* them altogether.
Am I missing something?
M. -- Jazz is not dead. It just smells funny...
|  |