On Wed, Oct 19, 2022 at 10:13 AM Lorenzo Pieralisi
<lpieralisi@xxxxxxxxxx> wrote:
>
> On Tue, Oct 18, 2022 at 02:14:04PM +0100, Robin Murphy wrote:
> > Assigning the device's dma_range_map from the iterator variable after
> > the loop means it always points to the empty terminator at the end of
> > the map, which is not what we want. Similarly, freeing the iterator on
> > error when it points to somwhere in the middle of the allocated array
> > won't work either. Fix this.
> >
> > Fixes: bf2ee8d0c385 ("ACPI: scan: Support multiple DMA windows with different offsets")
> > Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
> > ---
> > drivers/acpi/scan.c | 7 ++++---
> > 1 file changed, 4 insertions(+), 3 deletions(-)
>
> A quick comment below, otherwise:
>
> Reviewed-by: Lorenzo Pieralisi <lpieralisi@xxxxxxxxxx>
Applied as is and the code may be cleaned up later.
Thanks!
> > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
> > index 558664d169fc..024cc373a197 100644
> > --- a/drivers/acpi/scan.c
> > +++ b/drivers/acpi/scan.c
> > @@ -1509,9 +1509,12 @@ int acpi_dma_get_range(struct device *dev, const struct bus_dma_region **map)
> > goto out;
> > }
> >
> > + *map = r;
>
> I wonder whether having a local variable to stash the base pointer
> would make code easier to read (so that we avoid using *map for that
> purpose and also to return the array to the caller).
>
> Thanks for fixing it so promptly.
>
> Lorenzo
>
> > +
> > list_for_each_entry(rentry, &list, node) {
> > if (rentry->res->start >= rentry->res->end) {
> > - kfree(r);
> > + kfree(*map);
> > + *map = NULL;
> > ret = -EINVAL;
> > dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
> > goto out;
> > @@ -1523,8 +1526,6 @@ int acpi_dma_get_range(struct device *dev, const struct bus_dma_region **map)
> > r->offset = rentry->offset;
> > r++;
> > }
> > -
> > - *map = r;
> > }
> > out:
> > acpi_dev_free_resource_list(&list);
> > --
> > 2.36.1.dirty
> >
