This is a note to let you know that I've just added the patch titled
cxl/region: Fix cxl_region leak, cleanup targets at region delete
to the 6.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
cxl-region-fix-cxl_region-leak-cleanup-targets-at-region-delete.patch
and it can be found in the queue-6.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 0d9e734018d70cecf79e2e4c6082167160a0f13f Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams@xxxxxxxxx>
Date: Thu, 3 Nov 2022 17:30:30 -0700
Subject: cxl/region: Fix cxl_region leak, cleanup targets at region delete
From: Dan Williams <dan.j.williams@xxxxxxxxx>
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@xxxxxxxxxxxxxxx>
Fixes: b9686e8c8e39 ("cxl/region: Enable the assignment of endpoint decoders to regions")
Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Reviewed-by: Vishal Verma <vishal.l.verma@xxxxxxxxx>
Link: https://lore.kernel.org/r/166752183055.947915.17681995648556534844.stgit@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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);
}
Patches currently in stable-queue which might be from dan.j.williams@xxxxxxxxx are
queue-6.0/cxl-region-fix-distance-calculation-with-passthrough-ports.patch
queue-6.0/acpi-numa-add-cxl-cfmws-nodes-to-the-possible-nodes-set.patch
queue-6.0/cxl-region-fix-decoder-allocation-crash.patch
queue-6.0/cxl-pmem-fix-cxl_pmem_region-and-cxl_memdev-leak.patch
queue-6.0/cxl-region-fix-region-hpa-ordering-validation.patch
queue-6.0/cxl-region-fix-cxl_region-leak-cleanup-targets-at-region-delete.patch
