Patch "radix tree test suite: Register the main thread with the RCU library" has been added to the 5.11-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    radix tree test suite: Register the main thread with the RCU library

to the 5.11-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:
     radix-tree-test-suite-register-the-main-thread-with-.patch
and it can be found in the queue-5.11 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 0827641265f5e304ca1683d563e9bc208d6fb3a9
Author: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Date:   Wed Mar 31 14:59:19 2021 -0400

    radix tree test suite: Register the main thread with the RCU library
    
    [ Upstream commit 1bb4bd266cf39fd2fa711f2d265c558b92df1119 ]
    
    Several test runners register individual worker threads with the
    RCU library, but neglect to register the main thread, which can lead
    to objects being freed while the main thread is in what appears to be
    an RCU critical section.
    
    Reported-by: Chris von Recklinghausen <crecklin@xxxxxxxxxx>
    Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/tools/testing/radix-tree/idr-test.c b/tools/testing/radix-tree/idr-test.c
index 3b796dd5e577..44ceff95a9b3 100644
--- a/tools/testing/radix-tree/idr-test.c
+++ b/tools/testing/radix-tree/idr-test.c
@@ -577,6 +577,7 @@ void ida_tests(void)
 
 int __weak main(void)
 {
+	rcu_register_thread();
 	radix_tree_init();
 	idr_checks();
 	ida_tests();
@@ -584,5 +585,6 @@ int __weak main(void)
 	rcu_barrier();
 	if (nr_allocated)
 		printf("nr_allocated = %d\n", nr_allocated);
+	rcu_unregister_thread();
 	return 0;
 }
diff --git a/tools/testing/radix-tree/multiorder.c b/tools/testing/radix-tree/multiorder.c
index 9eae0fb5a67d..e00520cc6349 100644
--- a/tools/testing/radix-tree/multiorder.c
+++ b/tools/testing/radix-tree/multiorder.c
@@ -224,7 +224,9 @@ void multiorder_checks(void)
 
 int __weak main(void)
 {
+	rcu_register_thread();
 	radix_tree_init();
 	multiorder_checks();
+	rcu_unregister_thread();
 	return 0;
 }
diff --git a/tools/testing/radix-tree/xarray.c b/tools/testing/radix-tree/xarray.c
index e61e43efe463..f20e12cbbfd4 100644
--- a/tools/testing/radix-tree/xarray.c
+++ b/tools/testing/radix-tree/xarray.c
@@ -25,11 +25,13 @@ void xarray_tests(void)
 
 int __weak main(void)
 {
+	rcu_register_thread();
 	radix_tree_init();
 	xarray_tests();
 	radix_tree_cpu_dead(1);
 	rcu_barrier();
 	if (nr_allocated)
 		printf("nr_allocated = %d\n", nr_allocated);
+	rcu_unregister_thread();
 	return 0;
 }