From: Matthew Wilcox (Oracle) willy@infradead.org
[ Upstream commit 703586410da69eb40062e64d413ca33bd735917a ]
When run on a single CPU, this test would frequently access already-freed memory. Due to timing, this bug never showed up on multi-CPU tests.
Reported-by: Chris von Recklinghausen crecklin@redhat.com Signed-off-by: Matthew Wilcox (Oracle) willy@infradead.org Signed-off-by: Sasha Levin sashal@kernel.org --- tools/testing/radix-tree/idr-test.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/tools/testing/radix-tree/idr-test.c b/tools/testing/radix-tree/idr-test.c index 44ceff95a9b3..4a9b451b7ba0 100644 --- a/tools/testing/radix-tree/idr-test.c +++ b/tools/testing/radix-tree/idr-test.c @@ -306,11 +306,15 @@ void idr_find_test_1(int anchor_id, int throbber_id) BUG_ON(idr_alloc(&find_idr, xa_mk_value(anchor_id), anchor_id, anchor_id + 1, GFP_KERNEL) != anchor_id);
+ rcu_read_lock(); do { int id = 0; void *entry = idr_get_next(&find_idr, &id); + rcu_read_unlock(); BUG_ON(entry != xa_mk_value(id)); + rcu_read_lock(); } while (time(NULL) < start + 11); + rcu_read_unlock();
pthread_join(throbber, NULL);