Commit-ID: 42eb088ed246a5a817bb45a8b32fe234cf1c0f8b Gitweb: http://git.kernel.org/tip/42eb088ed246a5a817bb45a8b32fe234cf1c0f8b Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx> AuthorDate: Tue, 19 Nov 2013 16:41:49 +0100 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Tue, 19 Nov 2013 17:01:16 +0100 sched: Avoid NULL dereference on sd_busy Commit 37dc6b50cee9 ("sched: Remove unnecessary iteration over sched domains to update nr_busy_cpus") forgot to clear 'sd_busy' under some conditions leading to a possible NULL deref in set_cpu_sd_state_idle(). Reported-by: Anton Blanchard <anton@xxxxxxxxx> Cc: Preeti U Murthy <preeti@xxxxxxxxxxxxxxxxxx> Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/20131118113701.GF3866@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- kernel/sched/core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index c180860..a1591ca 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -4910,8 +4910,9 @@ static void update_top_cache_domain(int cpu) if (sd) { id = cpumask_first(sched_domain_span(sd)); size = cpumask_weight(sched_domain_span(sd)); - rcu_assign_pointer(per_cpu(sd_busy, cpu), sd->parent); + sd = sd->parent; /* sd_busy */ } + rcu_assign_pointer(per_cpu(sd_busy, cpu), sd); rcu_assign_pointer(per_cpu(sd_llc, cpu), sd); per_cpu(sd_llc_size, cpu) = size; -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html