On Tue, Mar 6, 2012 at 12:13 AM, Yinghai Lu <yinghai@xxxxxxxxxx> wrote:
> During testing pci root bus removal, found some root bus bridge is not freed.
>
> If booting with pnpacpi=off, those hostbridge could be freed without problem.
>
> It turns out that some devices reference are not released during acpi_pnp_match.
>
> that match should not hold one device ref during every calling.
>
> Add put_device calling before returning.
>
> Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
> Cc: stable@xxxxxxxxxx
> Cc: Len Brown <lenb@xxxxxxxxxx>
> Cc: Adam Belay <abelay@xxxxxxx>
> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Cc: linux-acpi@xxxxxxxxxxxxxxx
> ---
> drivers/pnp/pnpacpi/core.c | 7 ++++++-
> 1 files changed, 6 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/pnp/pnpacpi/core.c b/drivers/pnp/pnpacpi/core.c
> index b00c176..d21e8f5 100644
> --- a/drivers/pnp/pnpacpi/core.c
> +++ b/drivers/pnp/pnpacpi/core.c
> @@ -321,9 +321,14 @@ static int __init acpi_pnp_match(struct device *dev, void *_pnp)
> {
> struct acpi_device *acpi = to_acpi_device(dev);
> struct pnp_dev *pnp = _pnp;
> + struct device *physical_device;
> +
> + physical_device = acpi_get_physical_device(acpi->handle);
> + if (physical_device)
> + put_device(physical_device);
>
> /* true means it matched */
> - return !acpi_get_physical_device(acpi->handle)
> + return !physical_device
> && compare_pnp_id(pnp->id, acpi_device_hid(acpi));
> }
>
I spent about an hour convincing myself that this patch does the right
thing. I *think* it does, but it certainly is not obvious. It's
always nicer if the get/put are in the same function or in functions
that obviously correspond to each other. But you didn't create this
mess, so I don't hold you responsible for fixing it :)
Bjorn
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
