From: Dan Williams dan.j.williams@intel.com
commit 0d9e734018d70cecf79e2e4c6082167160a0f13f upstream.
When a region is deleted any targets that have been previously assigned to that region hold references to it. Trigger those references to drop by detaching all targets at unregister_region() time.
Otherwise that region object will leak as userspace has lost the ability to detach targets once region sysfs is torn down.
Cc: stable@vger.kernel.org Fixes: b9686e8c8e39 ("cxl/region: Enable the assignment of endpoint decoders to regions") Reviewed-by: Dave Jiang dave.jiang@intel.com Reviewed-by: Vishal Verma vishal.l.verma@intel.com Link: https://lore.kernel.org/r/166752183055.947915.17681995648556534844.stgit@dwi... Signed-off-by: Dan Williams dan.j.williams@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/cxl/core/region.c | 11 +++++++++++ 1 file changed, 11 insertions(+)
--- a/drivers/cxl/core/region.c +++ b/drivers/cxl/core/region.c @@ -1556,8 +1556,19 @@ static struct cxl_region *to_cxl_region( static void unregister_region(void *dev) { struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + int i;
device_del(dev); + + /* + * Now that region sysfs is shutdown, the parameter block is now + * read-only, so no need to hold the region rwsem to access the + * region parameters. + */ + for (i = 0; i < p->interleave_ways; i++) + detach_target(cxlr, i); + cxl_region_iomem_release(cxlr); put_device(dev); }