Le Tue, 28 Feb 2023 17:14:18 -0600, Rob Herring <robh+dt@xxxxxxxxxx> a écrit : > +Saravana, Jean > > On Tue, Jan 17, 2023 at 8:47 AM Clément Léger <clement.leger@xxxxxxxxxxx> wrote: > > > > After calling of_irq_parse_one(), the node provided in the of_phandle_args > > has a refcount increment by one. Add missing of_node_put in of_irq_get() > > to decrement the refcount once used. > > > > Signed-off-by: Clément Léger <clement.leger@xxxxxxxxxxx> > > --- > > > > While debugging a refcount problem with OF_DYNAMIC enabled (which is > > actually the only case were node refcount are really used), I noticed that > > platform_get_irq() was actually incrementing the refcount of an interrupt > > controller node. Digging into that function shows that it calls > > of_irq_get() which calls of_irq_parse_one() and finally of_irq_parse_raw(). > > Since it seems sane that the node returned in the of_phandle_args has a > > refcount incremented, I thought it is better to put the of_node_put() in > > the user even though it was hard to find any user doing so. > > While investigating [1], I stumbled back on this. Was the failing case > you had using interrupts-extended? It looks to me like that path has a > get, but the 'interrupts' path does not. If so, this change is wrong. In my case, it was with a classic "interrupts" property. I can take another look at the internal code to be sure this fix is correct. Clément > > Rob > > [1] https://lore.kernel.org/all/20230228174019.4004581-1-jjhiblot@xxxxxxxxxxxxxxx/ > > > > > > drivers/of/irq.c | 12 +++++++++--- > > 1 file changed, 9 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/of/irq.c b/drivers/of/irq.c > > index e9bf5236ed89..174900072c18 100644 > > --- a/drivers/of/irq.c > > +++ b/drivers/of/irq.c > > @@ -438,10 +438,16 @@ int of_irq_get(struct device_node *dev, int index) > > return rc; > > > > domain = irq_find_host(oirq.np); > > - if (!domain) > > - return -EPROBE_DEFER; > > + if (!domain) { > > + rc = -EPROBE_DEFER; > > + goto out; > > + } > > > > - return irq_create_of_mapping(&oirq); > > + rc = irq_create_of_mapping(&oirq); > > +out: > > + of_node_put(oirq.np); > > + > > + return rc; > > } > > EXPORT_SYMBOL_GPL(of_irq_get); > > > > -- > > 2.39.0 > > -- Clément Léger, Embedded Linux and Kernel engineer at Bootlin https://bootlin.com
