Re: [PATCH] media: saa7164: fix cleanup on resource allocation failure

[Guangshuo Li]

Hi Hans,

On Wed, 15 Jul 2026 at 19:40, Hans Verkuil <hverkuil+cisco@xxxxxxxxxx> wrote:
>
> On 08/07/2026 09:21, Guangshuo Li wrote:
> > saa7164_dev_setup() adds the device to the global saa7164_devlist before
> > requesting the PCI BAR memory regions.
> >
> > If get_resources() fails, saa7164_dev_setup() decrements the device count
> > and returns an error, but leaves the device on saa7164_devlist. The probe
> > error path then frees the device, leaving a dangling entry on the global
> > list.
> >
> > Remove the device from saa7164_devlist before returning from the
> > get_resources() failure path, matching the cleanup done by the ioremap
> > failure paths.
> >
> > Also release BAR0 if BAR0 was successfully requested but the BAR2
> > request fails.
> >
> > Fixes: 443c1228d505 ("V4L/DVB (12923): SAA7164: Add support for the NXP SAA7164 silicon")
> > Signed-off-by: Guangshuo Li <lgs201920130244@xxxxxxxxx>
> > ---
> >  drivers/media/pci/saa7164/saa7164-core.c | 6 ++++++
> >  1 file changed, 6 insertions(+)
> >
> > diff --git a/drivers/media/pci/saa7164/saa7164-core.c b/drivers/media/pci/saa7164/saa7164-core.c
> > index 6bcde506adf5..225dbd3650da 100644
> > --- a/drivers/media/pci/saa7164/saa7164-core.c
> > +++ b/drivers/media/pci/saa7164/saa7164-core.c
> > @@ -878,6 +878,9 @@ static int get_resources(struct saa7164_dev *dev)
> >               if (request_mem_region(pci_resource_start(dev->pci, 2),
> >                       pci_resource_len(dev->pci, 2), dev->name))
> >                       return 0;
> > +
> > +             release_mem_region(pci_resource_start(dev->pci, 0),
> > +                                pci_resource_len(dev->pci, 0));
> >       }
> >
> >       printk(KERN_ERR "%s: can't get MMIO memory @ 0x%llx or 0x%llx\n",
> > @@ -999,6 +1002,9 @@ static int saa7164_dev_setup(struct saa7164_dev *dev)
> >               printk(KERN_ERR "CORE %s No more PCIe resources for subsystem: %04x:%04x\n",
> >                      dev->name, dev->pci->subsystem_vendor,
> >                      dev->pci->subsystem_device);
> > +             scoped_guard(mutex, &devlist) {
> > +                     list_del(&dev->devlist);
> > +             }
> >
> >               saa7164_devcount--;
>
> This should just be a goto into the error handling. You just need to add a new goto label
> right after the 'release_resources' call.
>
> >               return -ENODEV;
>
> This patch looks good otherwise.
>
> Regards,
>
>         Hans

Thank you for reviewing the patch. I will follow your suggestion and send a v2.

Best regards,
Guangshuo