linux内核bug Red Hat Bugzilla BZ#1890123 分析 资料

参考

RHSA-2020:5418-01: Moderate: kernel security and bug fix update

其中有

* Scheduler: rq->tmp_alone_branch != &rq->leaf_cfs_rq_list (BZ#1890123)

直接访问

https://bugzilla.redhat.com/show_bug.cgi?id=1890123

发现未登录不允许访问

 邮件注册后，仍然无权限

bugzilla.kernel.org没有这个bug

bing搜索到的资料

Linux-Kernel Archive: [PATCH] test: rq->tmp_alone_branch != &rq->leaf_cfs_rq_list 

Signed-off-by: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>
---
kernel/sched/fair.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 3c8a379c357e..69fc30db7440 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4619,6 +4619,15 @@ void unthrottle_cfs_rq(struct cfs_rq *cfs_rq)
break;
}

+ if (rq->tmp_alone_branch != &rq->leaf_cfs_rq_list) {
+ char path[64];
+
+ sched_trace_cfs_rq_path(cfs_rq, path, 64);
+
+ printk("CPU%d path=%s on_list=%d nr_running=%d\n",
+ cpu_of(rq), path, cfs_rq->on_list, cfs_rq->nr_running);
+ }
+
assert_list_leaf_cfs_rq(rq);

if (!se)
@@ -5320,6 +5329,18 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
}
}

+ if (rq->tmp_alone_branch != &rq->leaf_cfs_rq_list) {
+ char path[64];
+
+ cfs_rq = cfs_rq_of(&p->se);
+
+ sched_trace_cfs_rq_path(cfs_rq, path, 64);
+
+ printk("CPU%d path=%s on_list=%d nr_running=%d p=[%s %d]\n",
+ cpu_of(rq), path, cfs_rq->on_list, cfs_rq->nr_running,
+ p->comm, p->pid);
+ }
+
assert_list_leaf_cfs_rq(rq);

hrtick_update(rq);
--
2.17.1