On Thu, 2022-11-03 at 17:30 -0700, Dan Williams wrote:
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") Signed-off-by: Dan Williams dan.j.williams@intel.com
drivers/cxl/core/region.c | 11 +++++++++++ 1 file changed, 11 insertions(+)
Looks good,
Reviewed-by: Vishal Verma vishal.l.verma@intel.com
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c index d26ca7a6beae..c52465e09f26 100644 --- a/drivers/cxl/core/region.c +++ b/drivers/cxl/core/region.c @@ -1557,8 +1557,19 @@ static struct cxl_region *to_cxl_region(struct device *dev) 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); }