From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> stable inclusion from stable-5.10.58 commit 14673e19291c49e5d53258e98d1c2da27f468525 bugzilla: 176984 https://gitee.com/openeuler/kernel/issues/I4E2P4 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit f7ec4121256393e1d03274acdca73eb18958f27e upstream. On transition from 2->1 callees, we should be comparing .data rather than .func, because the same callback can be registered twice with different data, and what we care about here is that the data of array element 0 is unchanged to skip rcu sync. Link: https://lkml.kernel.org/r/20210805132717.23813-2-mathieu.desnoyers@efficios.... Link: https://lore.kernel.org/io-uring/4ebea8f0-58c9-e571-fd30-0ce4f6f09c70@samba.... Cc: stable@vger.kernel.org Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Stefan Metzmacher <metze@samba.org> Fixes: 547305a64632 ("tracepoint: Fix out of sync data passing by static caller") Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- kernel/tracepoint.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c index 1f490638b2dc..ceb851cb08de 100644 --- a/kernel/tracepoint.c +++ b/kernel/tracepoint.c @@ -359,7 +359,7 @@ static int tracepoint_remove_func(struct tracepoint *tp, } else { rcu_assign_pointer(tp->funcs, tp_funcs); tracepoint_update_call(tp, tp_funcs, - tp_funcs[0].func != old[0].func); + tp_funcs[0].data != old[0].data); } release_probes(old); return 0; -- 2.20.1