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-rw-r--r--kernel/sched/core.c43
-rw-r--r--kernel/sched/cputime.c6
-rw-r--r--kernel/sched/fair.c36
-rw-r--r--kernel/sched/membarrier.c1
-rw-r--r--kernel/sched/topology.c11
5 files changed, 41 insertions, 56 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 7880f4f64d0e..dd05a378631a 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5106,9 +5106,6 @@ static int sched_copy_attr(struct sched_attr __user *uattr, struct sched_attr *a
u32 size;
int ret;
- if (!access_ok(uattr, SCHED_ATTR_SIZE_VER0))
- return -EFAULT;
-
/* Zero the full structure, so that a short copy will be nice: */
memset(attr, 0, sizeof(*attr));
@@ -5116,45 +5113,19 @@ static int sched_copy_attr(struct sched_attr __user *uattr, struct sched_attr *a
if (ret)
return ret;
- /* Bail out on silly large: */
- if (size > PAGE_SIZE)
- goto err_size;
-
/* ABI compatibility quirk: */
if (!size)
size = SCHED_ATTR_SIZE_VER0;
-
- if (size < SCHED_ATTR_SIZE_VER0)
+ if (size < SCHED_ATTR_SIZE_VER0 || size > PAGE_SIZE)
goto err_size;
- /*
- * If we're handed a bigger struct than we know of,
- * ensure all the unknown bits are 0 - i.e. new
- * user-space does not rely on any kernel feature
- * extensions we dont know about yet.
- */
- if (size > sizeof(*attr)) {
- unsigned char __user *addr;
- unsigned char __user *end;
- unsigned char val;
-
- addr = (void __user *)uattr + sizeof(*attr);
- end = (void __user *)uattr + size;
-
- for (; addr < end; addr++) {
- ret = get_user(val, addr);
- if (ret)
- return ret;
- if (val)
- goto err_size;
- }
- size = sizeof(*attr);
+ ret = copy_struct_from_user(attr, sizeof(*attr), uattr, size);
+ if (ret) {
+ if (ret == -E2BIG)
+ goto err_size;
+ return ret;
}
- ret = copy_from_user(attr, uattr, size);
- if (ret)
- return -EFAULT;
-
if ((attr->sched_flags & SCHED_FLAG_UTIL_CLAMP) &&
size < SCHED_ATTR_SIZE_VER1)
return -EINVAL;
@@ -5354,7 +5325,7 @@ sched_attr_copy_to_user(struct sched_attr __user *uattr,
* sys_sched_getattr - similar to sched_getparam, but with sched_attr
* @pid: the pid in question.
* @uattr: structure containing the extended parameters.
- * @usize: sizeof(attr) that user-space knows about, for forwards and backwards compatibility.
+ * @usize: sizeof(attr) for fwd/bwd comp.
* @flags: for future extension.
*/
SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr,
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 2305ce89a26c..46ed4e1383e2 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -740,7 +740,7 @@ void vtime_account_system(struct task_struct *tsk)
write_seqcount_begin(&vtime->seqcount);
/* We might have scheduled out from guest path */
- if (current->flags & PF_VCPU)
+ if (tsk->flags & PF_VCPU)
vtime_account_guest(tsk, vtime);
else
__vtime_account_system(tsk, vtime);
@@ -783,7 +783,7 @@ void vtime_guest_enter(struct task_struct *tsk)
*/
write_seqcount_begin(&vtime->seqcount);
__vtime_account_system(tsk, vtime);
- current->flags |= PF_VCPU;
+ tsk->flags |= PF_VCPU;
write_seqcount_end(&vtime->seqcount);
}
EXPORT_SYMBOL_GPL(vtime_guest_enter);
@@ -794,7 +794,7 @@ void vtime_guest_exit(struct task_struct *tsk)
write_seqcount_begin(&vtime->seqcount);
vtime_account_guest(tsk, vtime);
- current->flags &= ~PF_VCPU;
+ tsk->flags &= ~PF_VCPU;
write_seqcount_end(&vtime->seqcount);
}
EXPORT_SYMBOL_GPL(vtime_guest_exit);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 83ab35e2374f..682a754ea3e1 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4926,20 +4926,28 @@ static enum hrtimer_restart sched_cfs_period_timer(struct hrtimer *timer)
if (++count > 3) {
u64 new, old = ktime_to_ns(cfs_b->period);
- new = (old * 147) / 128; /* ~115% */
- new = min(new, max_cfs_quota_period);
-
- cfs_b->period = ns_to_ktime(new);
-
- /* since max is 1s, this is limited to 1e9^2, which fits in u64 */
- cfs_b->quota *= new;
- cfs_b->quota = div64_u64(cfs_b->quota, old);
-
- pr_warn_ratelimited(
- "cfs_period_timer[cpu%d]: period too short, scaling up (new cfs_period_us %lld, cfs_quota_us = %lld)\n",
- smp_processor_id(),
- div_u64(new, NSEC_PER_USEC),
- div_u64(cfs_b->quota, NSEC_PER_USEC));
+ /*
+ * Grow period by a factor of 2 to avoid losing precision.
+ * Precision loss in the quota/period ratio can cause __cfs_schedulable
+ * to fail.
+ */
+ new = old * 2;
+ if (new < max_cfs_quota_period) {
+ cfs_b->period = ns_to_ktime(new);
+ cfs_b->quota *= 2;
+
+ pr_warn_ratelimited(
+ "cfs_period_timer[cpu%d]: period too short, scaling up (new cfs_period_us = %lld, cfs_quota_us = %lld)\n",
+ smp_processor_id(),
+ div_u64(new, NSEC_PER_USEC),
+ div_u64(cfs_b->quota, NSEC_PER_USEC));
+ } else {
+ pr_warn_ratelimited(
+ "cfs_period_timer[cpu%d]: period too short, but cannot scale up without losing precision (cfs_period_us = %lld, cfs_quota_us = %lld)\n",
+ smp_processor_id(),
+ div_u64(old, NSEC_PER_USEC),
+ div_u64(cfs_b->quota, NSEC_PER_USEC));
+ }
/* reset count so we don't come right back in here */
count = 0;
diff --git a/kernel/sched/membarrier.c b/kernel/sched/membarrier.c
index a39bed2c784f..168479a7d61b 100644
--- a/kernel/sched/membarrier.c
+++ b/kernel/sched/membarrier.c
@@ -174,7 +174,6 @@ static int membarrier_private_expedited(int flags)
*/
if (cpu == raw_smp_processor_id())
continue;
- rcu_read_lock();
p = rcu_dereference(cpu_rq(cpu)->curr);
if (p && p->mm == mm)
__cpumask_set_cpu(cpu, tmpmask);
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index b5667a273bf6..49b835f1305f 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -1948,7 +1948,7 @@ next_level:
static int
build_sched_domains(const struct cpumask *cpu_map, struct sched_domain_attr *attr)
{
- enum s_alloc alloc_state;
+ enum s_alloc alloc_state = sa_none;
struct sched_domain *sd;
struct s_data d;
struct rq *rq = NULL;
@@ -1956,6 +1956,9 @@ build_sched_domains(const struct cpumask *cpu_map, struct sched_domain_attr *att
struct sched_domain_topology_level *tl_asym;
bool has_asym = false;
+ if (WARN_ON(cpumask_empty(cpu_map)))
+ goto error;
+
alloc_state = __visit_domain_allocation_hell(&d, cpu_map);
if (alloc_state != sa_rootdomain)
goto error;
@@ -2026,7 +2029,7 @@ build_sched_domains(const struct cpumask *cpu_map, struct sched_domain_attr *att
rcu_read_unlock();
if (has_asym)
- static_branch_enable_cpuslocked(&sched_asym_cpucapacity);
+ static_branch_inc_cpuslocked(&sched_asym_cpucapacity);
if (rq && sched_debug_enabled) {
pr_info("root domain span: %*pbl (max cpu_capacity = %lu)\n",
@@ -2121,8 +2124,12 @@ int sched_init_domains(const struct cpumask *cpu_map)
*/
static void detach_destroy_domains(const struct cpumask *cpu_map)
{
+ unsigned int cpu = cpumask_any(cpu_map);
int i;
+ if (rcu_access_pointer(per_cpu(sd_asym_cpucapacity, cpu)))
+ static_branch_dec_cpuslocked(&sched_asym_cpucapacity);
+
rcu_read_lock();
for_each_cpu(i, cpu_map)
cpu_attach_domain(NULL, &def_root_domain, i);