From: Peter Zijlstra <peterz@infradead.org> mainline inclusion from mainline-v5.14-rc1 commit 85dd3f61203c5cfa72b308ff327b5fbf3fc1ce5e category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I5OOWG CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------------------------------------------------- Note that sched_core_fork() is called from under tasklist_lock, and not from sched_fork() earlier. This avoids a few races later. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Don Hiatt <dhiatt@digitalocean.com> Tested-by: Hongyu Ning <hongyu.ning@linux.intel.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lkml.kernel.org/r/20210422123308.980003687@infradead.org Signed-off-by: Lin Shengwang <linshengwang1@huawei.com> Reviewed-by: lihua <hucool.lihua@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- include/linux/sched.h | 2 ++ kernel/fork.c | 3 +++ kernel/sched/core_sched.c | 6 ++++++ 3 files changed, 11 insertions(+) diff --git a/include/linux/sched.h b/include/linux/sched.h index 6f8e0cb8b55b..a133a67a1b86 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2175,8 +2175,10 @@ const struct cpumask *sched_trace_rd_span(struct root_domain *rd); #ifdef CONFIG_SCHED_CORE extern void sched_core_free(struct task_struct *tsk); +extern void sched_core_fork(struct task_struct *p); #else static inline void sched_core_free(struct task_struct *tsk) { } +static inline void sched_core_fork(struct task_struct *p) { } #endif #ifdef CONFIG_QOS_SCHED diff --git a/kernel/fork.c b/kernel/fork.c index 628c2b3fafed..8a2e827815b6 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -2278,6 +2278,8 @@ static __latent_entropy struct task_struct *copy_process( klp_copy_process(p); + sched_core_fork(p); + spin_lock(¤t->sighand->siglock); /* @@ -2364,6 +2366,7 @@ static __latent_entropy struct task_struct *copy_process( return p; bad_fork_cancel_cgroup: + sched_core_free(p); spin_unlock(¤t->sighand->siglock); write_unlock_irq(&tasklist_lock); cgroup_cancel_fork(p, args); diff --git a/kernel/sched/core_sched.c b/kernel/sched/core_sched.c index 8d0869a9eb8c..dcbbeaefaaa3 100644 --- a/kernel/sched/core_sched.c +++ b/kernel/sched/core_sched.c @@ -103,6 +103,12 @@ static unsigned long sched_core_clone_cookie(struct task_struct *p) return cookie; } +void sched_core_fork(struct task_struct *p) +{ + RB_CLEAR_NODE(&p->core_node); + p->core_cookie = sched_core_clone_cookie(current); +} + void sched_core_free(struct task_struct *p) { sched_core_put_cookie(p->core_cookie); -- 2.20.1