Commit-ID: 185b42420b0948dfc00af6cc5d93aa00b7fef581 Gitweb: http://git.kernel.org/tip/185b42420b0948dfc00af6cc5d93aa00b7fef581 Author: Peter Zijlstra <pet...@infradead.org> AuthorDate: Tue, 29 Sep 2015 11:28:28 +0200 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Tue, 29 Sep 2015 12:27:40 +0200
sched/core: Robustify preemption leak checks When we warn about a preempt_count leak; reset the preempt_count to the known good value such that the problem does not ripple forward. Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Mike Galbraith <efa...@gmx.de> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: fweis...@gmail.com Cc: linux-kernel@vger.kernel.org Cc: o...@redhat.com Cc: rost...@goodmis.org Cc: umgwanakikb...@gmail.com Link: http://lkml.kernel.org/r/20150929093519.930244...@infradead.org Signed-off-by: Ingo Molnar <mi...@kernel.org> --- kernel/exit.c | 4 +++- kernel/sched/core.c | 4 +++- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/kernel/exit.c b/kernel/exit.c index ea95ee1..443677c 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -706,10 +706,12 @@ void do_exit(long code) smp_mb(); raw_spin_unlock_wait(&tsk->pi_lock); - if (unlikely(in_atomic())) + if (unlikely(in_atomic())) { pr_info("note: %s[%d] exited with preempt_count %d\n", current->comm, task_pid_nr(current), preempt_count()); + preempt_count_set(PREEMPT_ENABLED); + } /* sync mm's RSS info before statistics gathering */ if (tsk->mm) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index ecd585c..d1dec5d 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2953,8 +2953,10 @@ static inline void schedule_debug(struct task_struct *prev) * schedule() atomically, we ignore that path. Otherwise whine * if we are scheduling when we should not. */ - if (unlikely(in_atomic_preempt_off() && prev->state != TASK_DEAD)) + if (unlikely(in_atomic_preempt_off() && prev->state != TASK_DEAD)) { __schedule_bug(prev); + preempt_count_set(PREEMPT_DISABLED); + } rcu_sleep_check(); profile_hit(SCHED_PROFILING, __builtin_return_address(0)); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
