diff options
author | Kirill Tkhai <ktkhai@parallels.com> | 2014-09-22 14:36:24 -0400 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2014-09-24 08:47:09 -0400 |
commit | 66339c31bc3978d5fff9c4b4cb590a861def4db2 (patch) | |
tree | caf50db970fc626ee5c6d012fb365442c08d07ee /kernel/sched | |
parent | 7a96c231ca23f0f5622852307df4209afc502ec3 (diff) |
sched: Use dl_bw_of() under RCU read lock
dl_bw_of() dereferences rq->rd which has to have RCU read lock held.
Probability of use-after-free isn't zero here.
Also add lockdep assert into dl_bw_cpus().
Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org> # v3.14+
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140922183624.11015.71558.stgit@localhost
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/sched')
-rw-r--r-- | kernel/sched/core.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 5b0eac9f4e78..f0adb038170b 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c | |||
@@ -2021,6 +2021,8 @@ unsigned long to_ratio(u64 period, u64 runtime) | |||
2021 | #ifdef CONFIG_SMP | 2021 | #ifdef CONFIG_SMP |
2022 | inline struct dl_bw *dl_bw_of(int i) | 2022 | inline struct dl_bw *dl_bw_of(int i) |
2023 | { | 2023 | { |
2024 | rcu_lockdep_assert(rcu_read_lock_sched_held(), | ||
2025 | "sched RCU must be held"); | ||
2024 | return &cpu_rq(i)->rd->dl_bw; | 2026 | return &cpu_rq(i)->rd->dl_bw; |
2025 | } | 2027 | } |
2026 | 2028 | ||
@@ -2029,6 +2031,8 @@ static inline int dl_bw_cpus(int i) | |||
2029 | struct root_domain *rd = cpu_rq(i)->rd; | 2031 | struct root_domain *rd = cpu_rq(i)->rd; |
2030 | int cpus = 0; | 2032 | int cpus = 0; |
2031 | 2033 | ||
2034 | rcu_lockdep_assert(rcu_read_lock_sched_held(), | ||
2035 | "sched RCU must be held"); | ||
2032 | for_each_cpu_and(i, rd->span, cpu_active_mask) | 2036 | for_each_cpu_and(i, rd->span, cpu_active_mask) |
2033 | cpus++; | 2037 | cpus++; |
2034 | 2038 | ||
@@ -7645,6 +7649,8 @@ static int sched_dl_global_constraints(void) | |||
7645 | int cpu, ret = 0; | 7649 | int cpu, ret = 0; |
7646 | unsigned long flags; | 7650 | unsigned long flags; |
7647 | 7651 | ||
7652 | rcu_read_lock(); | ||
7653 | |||
7648 | /* | 7654 | /* |
7649 | * Here we want to check the bandwidth not being set to some | 7655 | * Here we want to check the bandwidth not being set to some |
7650 | * value smaller than the currently allocated bandwidth in | 7656 | * value smaller than the currently allocated bandwidth in |
@@ -7666,6 +7672,8 @@ static int sched_dl_global_constraints(void) | |||
7666 | break; | 7672 | break; |
7667 | } | 7673 | } |
7668 | 7674 | ||
7675 | rcu_read_unlock(); | ||
7676 | |||
7669 | return ret; | 7677 | return ret; |
7670 | } | 7678 | } |
7671 | 7679 | ||
@@ -7681,6 +7689,7 @@ static void sched_dl_do_global(void) | |||
7681 | if (global_rt_runtime() != RUNTIME_INF) | 7689 | if (global_rt_runtime() != RUNTIME_INF) |
7682 | new_bw = to_ratio(global_rt_period(), global_rt_runtime()); | 7690 | new_bw = to_ratio(global_rt_period(), global_rt_runtime()); |
7683 | 7691 | ||
7692 | rcu_read_lock(); | ||
7684 | /* | 7693 | /* |
7685 | * FIXME: As above... | 7694 | * FIXME: As above... |
7686 | */ | 7695 | */ |
@@ -7691,6 +7700,7 @@ static void sched_dl_do_global(void) | |||
7691 | dl_b->bw = new_bw; | 7700 | dl_b->bw = new_bw; |
7692 | raw_spin_unlock_irqrestore(&dl_b->lock, flags); | 7701 | raw_spin_unlock_irqrestore(&dl_b->lock, flags); |
7693 | } | 7702 | } |
7703 | rcu_read_unlock(); | ||
7694 | } | 7704 | } |
7695 | 7705 | ||
7696 | static int sched_rt_global_validate(void) | 7706 | static int sched_rt_global_validate(void) |