On Thu, Jun 23, 2022 at 07:45:14PM -0700, Dan Williams wrote:
> The upcoming region provisioning implementation has a need to
> dereference port->uport during the port unregister flow. Specifically,
> endpoint decoders need to be able to lookup their corresponding memdev
> via port->uport.
>
> The existing ->dead flag was added for cases where the core was
> committed to tearing down the port, but needed to drop locks before
> calling device_unregister(). Reuse that flag to indicate to
> delete_endpoint() that it has no "release action" work to do as
> unregister_port() will handle it.
>
> Fixes: 8dd2bc0f8e02 ("cxl/mem: Add the cxl_mem driver")
> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Reviewed-by: Alison Schofield <alison.schofield@xxxxxxxxx>
> ---
> drivers/cxl/core/port.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
> index dbce99bdffab..7810d1a8369b 100644
> --- a/drivers/cxl/core/port.c
> +++ b/drivers/cxl/core/port.c
> @@ -370,7 +370,7 @@ static void unregister_port(void *_port)
> lock_dev = &parent->dev;
>
> device_lock_assert(lock_dev);
> - port->uport = NULL;
> + port->dead = true;
> device_unregister(&port->dev);
> }
>
> @@ -857,7 +857,7 @@ static void delete_endpoint(void *data)
> parent = &parent_port->dev;
>
> device_lock(parent);
> - if (parent->driver && endpoint->uport) {
> + if (parent->driver && !endpoint->dead) {
> devm_release_action(parent, cxl_unlink_uport, endpoint);
> devm_release_action(parent, unregister_port, endpoint);
> }
>
