+ kfence-defer-kfence_test_init-to-ensure-that-kunit-debugfs-is-created.patch added to -mm tree

+ kfence-defer-kfence_test_init-to-ensure-that-kunit-debugfs-is-created.patch added to -mm tree

[akpm]

The patch titled
     Subject: kfence: defer kfence_test_init to ensure that kunit debugfs is created
has been added to the -mm tree.  Its filename is
     kfence-defer-kfence_test_init-to-ensure-that-kunit-debugfs-is-created.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/kfence-defer-kfence_test_init-to-ensure-that-kunit-debugfs-is-created.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/kfence-defer-kfence_test_init-to-ensure-that-kunit-debugfs-is-created.patch

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------------------------------------------------------
From: Weizhao Ouyang <o451686892@gmail.com>
Subject: kfence: defer kfence_test_init to ensure that kunit debugfs is created

kfence_test_init and kunit_init both use the same level late_initcall,
which means if kfence_test_init linked ahead of kunit_init,
kfence_test_init will get a NULL debugfs_rootdir as parent dentry, then
kfence_test_init and kfence_debugfs_init both create a debugfs node named
"kfence" under debugfs_mount->mnt_root, and it will throw out "debugfs:
Directory 'kfence' with parent '/' already present!" with EEXIST.  So
kfence_test_init should be deferred.

Link: https://lkml.kernel.org/r/20210714113140.2949995-1-o451686892@gmail.com
Signed-off-by: Weizhao Ouyang <o451686892@gmail.com>
Tested-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/kfence/kfence_test.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/kfence/kfence_test.c~kfence-defer-kfence_test_init-to-ensure-that-kunit-debugfs-is-created
+++ a/mm/kfence/kfence_test.c
@@ -852,7 +852,7 @@ static void kfence_test_exit(void)
 	tracepoint_synchronize_unregister();
 }
 
-late_initcall(kfence_test_init);
+late_initcall_sync(kfence_test_init);
 module_exit(kfence_test_exit);
 
 MODULE_LICENSE("GPL v2");
_

Patches currently in -mm which might be from o451686892@gmail.com are

kfence-defer-kfence_test_init-to-ensure-that-kunit-debugfs-is-created.patch