From: "Paul E. McKenney" <paulmck@kernel.org> mainline inclusion from mainline-v5.14-rc1 commit cf868c2af244417ed276ba7f716b980841a71340 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I4U05V CVE: NA ------------------------------------------------------------------------- Heavy networking load can cause a CPU to execute continuously and indefinitely within ksoftirqd, in which case there will be no voluntary task switches and thus no RCU-tasks quiescent states. This commit therefore causes the exiting rcu_softirq_qs() to provide an RCU-tasks quiescent state. This of course means that __do_softirq() and its callers cannot be invoked from within a tracing trampoline. Reported-by: Toke Høiland-Jørgensen <toke@redhat.com> Tested-by: Toke Høiland-Jørgensen <toke@redhat.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Reviewed-by: Cheng Jian <cj.chengjian@huawei.com> Reviewed-by: Cheng Jian <cj.chengjian@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- kernel/rcu/tree.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 1f6c78aa7bfd..b9c45b2d7690 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -236,6 +236,7 @@ void rcu_softirq_qs(void) { rcu_qs(); rcu_preempt_deferred_qs(current); + rcu_tasks_qs(current, false); } /* -- 2.20.1