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-rw-r--r--kernel/cpu.c6
-rw-r--r--kernel/futex.c52
-rw-r--r--kernel/kexec.c8
-rw-r--r--kernel/locking/rtmutex.c32
-rw-r--r--kernel/sched/core.c55
-rw-r--r--kernel/sched/cpudeadline.c33
-rw-r--r--kernel/sched/cpudeadline.h6
-rw-r--r--kernel/sched/cpupri.c7
-rw-r--r--kernel/sched/cpupri.h2
9 files changed, 153 insertions, 48 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c
index a9e710eef0e..247979a1b81 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -726,10 +726,12 @@ void set_cpu_present(unsigned int cpu, bool present)
void set_cpu_online(unsigned int cpu, bool online)
{
- if (online)
+ if (online) {
cpumask_set_cpu(cpu, to_cpumask(cpu_online_bits));
- else
+ cpumask_set_cpu(cpu, to_cpumask(cpu_active_bits));
+ } else {
cpumask_clear_cpu(cpu, to_cpumask(cpu_online_bits));
+ }
}
void set_cpu_active(unsigned int cpu, bool active)
diff --git a/kernel/futex.c b/kernel/futex.c
index 5f589279e46..81dbe773ce4 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -745,7 +745,8 @@ void exit_pi_state_list(struct task_struct *curr)
static int
lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
- union futex_key *key, struct futex_pi_state **ps)
+ union futex_key *key, struct futex_pi_state **ps,
+ struct task_struct *task)
{
struct futex_pi_state *pi_state = NULL;
struct futex_q *this, *next;
@@ -786,6 +787,16 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
return -EINVAL;
}
+ /*
+ * Protect against a corrupted uval. If uval
+ * is 0x80000000 then pid is 0 and the waiter
+ * bit is set. So the deadlock check in the
+ * calling code has failed and we did not fall
+ * into the check above due to !pid.
+ */
+ if (task && pi_state->owner == task)
+ return -EDEADLK;
+
atomic_inc(&pi_state->refcount);
*ps = pi_state;
@@ -803,6 +814,11 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
if (!p)
return -ESRCH;
+ if (!p->mm) {
+ put_task_struct(p);
+ return -EPERM;
+ }
+
/*
* We need to look at the task state flags to figure out,
* whether the task is exiting. To protect against the do_exit
@@ -935,7 +951,7 @@ retry:
* We dont have the lock. Look up the PI state (or create it if
* we are the first waiter):
*/
- ret = lookup_pi_state(uval, hb, key, ps);
+ ret = lookup_pi_state(uval, hb, key, ps, task);
if (unlikely(ret)) {
switch (ret) {
@@ -1347,7 +1363,7 @@ void requeue_pi_wake_futex(struct futex_q *q, union futex_key *key,
*
* Return:
* 0 - failed to acquire the lock atomically;
- * 1 - acquired the lock;
+ * >0 - acquired the lock, return value is vpid of the top_waiter
* <0 - error
*/
static int futex_proxy_trylock_atomic(u32 __user *pifutex,
@@ -1358,7 +1374,7 @@ static int futex_proxy_trylock_atomic(u32 __user *pifutex,
{
struct futex_q *top_waiter = NULL;
u32 curval;
- int ret;
+ int ret, vpid;
if (get_futex_value_locked(&curval, pifutex))
return -EFAULT;
@@ -1386,11 +1402,13 @@ static int futex_proxy_trylock_atomic(u32 __user *pifutex,
* the contended case or if set_waiters is 1. The pi_state is returned
* in ps in contended cases.
*/
+ vpid = task_pid_vnr(top_waiter->task);
ret = futex_lock_pi_atomic(pifutex, hb2, key2, ps, top_waiter->task,
set_waiters);
- if (ret == 1)
+ if (ret == 1) {
requeue_pi_wake_futex(top_waiter, key2, hb2);
-
+ return vpid;
+ }
return ret;
}
@@ -1421,7 +1439,6 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
struct futex_pi_state *pi_state = NULL;
struct futex_hash_bucket *hb1, *hb2;
struct futex_q *this, *next;
- u32 curval2;
if (requeue_pi) {
/*
@@ -1509,16 +1526,25 @@ retry_private:
* At this point the top_waiter has either taken uaddr2 or is
* waiting on it. If the former, then the pi_state will not
* exist yet, look it up one more time to ensure we have a
- * reference to it.
+ * reference to it. If the lock was taken, ret contains the
+ * vpid of the top waiter task.
*/
- if (ret == 1) {
+ if (ret > 0) {
WARN_ON(pi_state);
drop_count++;
task_count++;
- ret = get_futex_value_locked(&curval2, uaddr2);
- if (!ret)
- ret = lookup_pi_state(curval2, hb2, &key2,
- &pi_state);
+ /*
+ * If we acquired the lock, then the user
+ * space value of uaddr2 should be vpid. It
+ * cannot be changed by the top waiter as it
+ * is blocked on hb2 lock if it tries to do
+ * so. If something fiddled with it behind our
+ * back the pi state lookup might unearth
+ * it. So we rather use the known value than
+ * rereading and handing potential crap to
+ * lookup_pi_state.
+ */
+ ret = lookup_pi_state(ret, hb2, &key2, &pi_state, NULL);
}
switch (ret) {
diff --git a/kernel/kexec.c b/kernel/kexec.c
index c8380ad203b..28c57069ef6 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -1683,6 +1683,14 @@ int kernel_kexec(void)
kexec_in_progress = true;
kernel_restart_prepare(NULL);
migrate_to_reboot_cpu();
+
+ /*
+ * migrate_to_reboot_cpu() disables CPU hotplug assuming that
+ * no further code needs to use CPU hotplug (which is true in
+ * the reboot case). However, the kexec path depends on using
+ * CPU hotplug again; so re-enable it here.
+ */
+ cpu_hotplug_enable();
printk(KERN_EMERG "Starting new kernel\n");
machine_shutdown();
}
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index aa4dff04b59..a620d4d08ca 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -343,9 +343,16 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
* top_waiter can be NULL, when we are in the deboosting
* mode!
*/
- if (top_waiter && (!task_has_pi_waiters(task) ||
- top_waiter != task_top_pi_waiter(task)))
- goto out_unlock_pi;
+ if (top_waiter) {
+ if (!task_has_pi_waiters(task))
+ goto out_unlock_pi;
+ /*
+ * If deadlock detection is off, we stop here if we
+ * are not the top pi waiter of the task.
+ */
+ if (!detect_deadlock && top_waiter != task_top_pi_waiter(task))
+ goto out_unlock_pi;
+ }
/*
* When deadlock detection is off then we check, if further
@@ -361,7 +368,12 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
goto retry;
}
- /* Deadlock detection */
+ /*
+ * Deadlock detection. If the lock is the same as the original
+ * lock which caused us to walk the lock chain or if the
+ * current lock is owned by the task which initiated the chain
+ * walk, we detected a deadlock.
+ */
if (lock == orig_lock || rt_mutex_owner(lock) == top_task) {
debug_rt_mutex_deadlock(deadlock_detect, orig_waiter, lock);
raw_spin_unlock(&lock->wait_lock);
@@ -527,6 +539,18 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
unsigned long flags;
int chain_walk = 0, res;
+ /*
+ * Early deadlock detection. We really don't want the task to
+ * enqueue on itself just to untangle the mess later. It's not
+ * only an optimization. We drop the locks, so another waiter
+ * can come in before the chain walk detects the deadlock. So
+ * the other will detect the deadlock and return -EDEADLOCK,
+ * which is wrong, as the other waiter is not in a deadlock
+ * situation.
+ */
+ if (detect_deadlock && owner == task)
+ return -EDEADLK;
+
raw_spin_lock_irqsave(&task->pi_lock, flags);
__rt_mutex_adjust_prio(task);
waiter->task = task;
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 204d3d28180..0a725167898 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3195,17 +3195,40 @@ __getparam_dl(struct task_struct *p, struct sched_attr *attr)
* We ask for the deadline not being zero, and greater or equal
* than the runtime, as well as the period of being zero or
* greater than deadline. Furthermore, we have to be sure that
- * user parameters are above the internal resolution (1us); we
- * check sched_runtime only since it is always the smaller one.
+ * user parameters are above the internal resolution of 1us (we
+ * check sched_runtime only since it is always the smaller one) and
+ * below 2^63 ns (we have to check both sched_deadline and
+ * sched_period, as the latter can be zero).
*/
static bool
__checkparam_dl(const struct sched_attr *attr)
{
- return attr && attr->sched_deadline != 0 &&
- (attr->sched_period == 0 ||
- (s64)(attr->sched_period - attr->sched_deadline) >= 0) &&
- (s64)(attr->sched_deadline - attr->sched_runtime ) >= 0 &&
- attr->sched_runtime >= (2 << (DL_SCALE - 1));
+ /* deadline != 0 */
+ if (attr->sched_deadline == 0)
+ return false;
+
+ /*
+ * Since we truncate DL_SCALE bits, make sure we're at least
+ * that big.
+ */
+ if (attr->sched_runtime < (1ULL << DL_SCALE))
+ return false;
+
+ /*
+ * Since we use the MSB for wrap-around and sign issues, make
+ * sure it's not set (mind that period can be equal to zero).
+ */
+ if (attr->sched_deadline & (1ULL << 63) ||
+ attr->sched_period & (1ULL << 63))
+ return false;
+
+ /* runtime <= deadline <= period (if period != 0) */
+ if ((attr->sched_period != 0 &&
+ attr->sched_period < attr->sched_deadline) ||
+ attr->sched_deadline < attr->sched_runtime)
+ return false;
+
+ return true;
}
/*
@@ -3658,8 +3681,12 @@ SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr,
if (!uattr || pid < 0 || flags)
return -EINVAL;
- if (sched_copy_attr(uattr, &attr))
- return -EFAULT;
+ retval = sched_copy_attr(uattr, &attr);
+ if (retval)
+ return retval;
+
+ if (attr.sched_policy < 0)
+ return -EINVAL;
rcu_read_lock();
retval = -ESRCH;
@@ -3709,7 +3736,7 @@ SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid)
*/
SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
{
- struct sched_param lp;
+ struct sched_param lp = { .sched_priority = 0 };
struct task_struct *p;
int retval;
@@ -3726,11 +3753,8 @@ SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
if (retval)
goto out_unlock;
- if (task_has_dl_policy(p)) {
- retval = -EINVAL;
- goto out_unlock;
- }
- lp.sched_priority = p->rt_priority;
+ if (task_has_rt_policy(p))
+ lp.sched_priority = p->rt_priority;
rcu_read_unlock();
/*
@@ -5052,7 +5076,6 @@ static int sched_cpu_active(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_STARTING:
case CPU_DOWN_FAILED:
set_cpu_active((long)hcpu, true);
return NOTIFY_OK;
diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c
index ab001b5d504..bd95963dae8 100644
--- a/kernel/sched/cpudeadline.c
+++ b/kernel/sched/cpudeadline.c
@@ -13,6 +13,7 @@
#include <linux/gfp.h>
#include <linux/kernel.h>
+#include <linux/slab.h>
#include "cpudeadline.h"
static inline int parent(int i)
@@ -39,8 +40,10 @@ static void cpudl_exchange(struct cpudl *cp, int a, int b)
{
int cpu_a = cp->elements[a].cpu, cpu_b = cp->elements[b].cpu;
- swap(cp->elements[a], cp->elements[b]);
- swap(cp->cpu_to_idx[cpu_a], cp->cpu_to_idx[cpu_b]);
+ swap(cp->elements[a].cpu, cp->elements[b].cpu);
+ swap(cp->elements[a].dl , cp->elements[b].dl );
+
+ swap(cp->elements[cpu_a].idx, cp->elements[cpu_b].idx);
}
static void cpudl_heapify(struct cpudl *cp, int idx)
@@ -140,7 +143,7 @@ void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid)
WARN_ON(!cpu_present(cpu));
raw_spin_lock_irqsave(&cp->lock, flags);
- old_idx = cp->cpu_to_idx[cpu];
+ old_idx = cp->elements[cpu].idx;
if (!is_valid) {
/* remove item */
if (old_idx == IDX_INVALID) {
@@ -155,8 +158,8 @@ void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid)
cp->elements[old_idx].dl = cp->elements[cp->size - 1].dl;
cp->elements[old_idx].cpu = new_cpu;
cp->size--;
- cp->cpu_to_idx[new_cpu] = old_idx;
- cp->cpu_to_idx[cpu] = IDX_INVALID;
+ cp->elements[new_cpu].idx = old_idx;
+ cp->elements[cpu].idx = IDX_INVALID;
while (old_idx > 0 && dl_time_before(
cp->elements[parent(old_idx)].dl,
cp->elements[old_idx].dl)) {
@@ -173,7 +176,7 @@ void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid)
cp->size++;
cp->elements[cp->size - 1].dl = 0;
cp->elements[cp->size - 1].cpu = cpu;
- cp->cpu_to_idx[cpu] = cp->size - 1;
+ cp->elements[cpu].idx = cp->size - 1;
cpudl_change_key(cp, cp->size - 1, dl);
cpumask_clear_cpu(cpu, cp->free_cpus);
} else {
@@ -195,10 +198,21 @@ int cpudl_init(struct cpudl *cp)
memset(cp, 0, sizeof(*cp));
raw_spin_lock_init(&cp->lock);
cp->size = 0;
- for (i = 0; i < NR_CPUS; i++)
- cp->cpu_to_idx[i] = IDX_INVALID;
- if (!alloc_cpumask_var(&cp->free_cpus, GFP_KERNEL))
+
+ cp->elements = kcalloc(nr_cpu_ids,
+ sizeof(struct cpudl_item),
+ GFP_KERNEL);
+ if (!cp->elements)
+ return -ENOMEM;
+
+ if (!alloc_cpumask_var(&cp->free_cpus, GFP_KERNEL)) {
+ kfree(cp->elements);
return -ENOMEM;
+ }
+
+ for_each_possible_cpu(i)
+ cp->elements[i].idx = IDX_INVALID;
+
cpumask_setall(cp->free_cpus);
return 0;
@@ -211,4 +225,5 @@ int cpudl_init(struct cpudl *cp)
void cpudl_cleanup(struct cpudl *cp)
{
free_cpumask_var(cp->free_cpus);
+ kfree(cp->elements);
}
diff --git a/kernel/sched/cpudeadline.h b/kernel/sched/cpudeadline.h
index a202789a412..538c9796ad4 100644
--- a/kernel/sched/cpudeadline.h
+++ b/kernel/sched/cpudeadline.h
@@ -5,17 +5,17 @@
#define IDX_INVALID -1
-struct array_item {
+struct cpudl_item {
u64 dl;
int cpu;
+ int idx;
};
struct cpudl {
raw_spinlock_t lock;
int size;
- int cpu_to_idx[NR_CPUS];
- struct array_item elements[NR_CPUS];
cpumask_var_t free_cpus;
+ struct cpudl_item *elements;
};
diff --git a/kernel/sched/cpupri.c b/kernel/sched/cpupri.c
index 3031bac8aa3..8834243abee 100644
--- a/kernel/sched/cpupri.c
+++ b/kernel/sched/cpupri.c
@@ -30,6 +30,7 @@
#include <linux/gfp.h>
#include <linux/sched.h>
#include <linux/sched/rt.h>
+#include <linux/slab.h>
#include "cpupri.h"
/* Convert between a 140 based task->prio, and our 102 based cpupri */
@@ -218,8 +219,13 @@ int cpupri_init(struct cpupri *cp)
goto cleanup;
}
+ cp->cpu_to_pri = kcalloc(nr_cpu_ids, sizeof(int), GFP_KERNEL);
+ if (!cp->cpu_to_pri)
+ goto cleanup;
+
for_each_possible_cpu(i)
cp->cpu_to_pri[i] = CPUPRI_INVALID;
+
return 0;
cleanup:
@@ -236,6 +242,7 @@ void cpupri_cleanup(struct cpupri *cp)
{
int i;
+ kfree(cp->cpu_to_pri);
for (i = 0; i < CPUPRI_NR_PRIORITIES; i++)
free_cpumask_var(cp->pri_to_cpu[i].mask);
}
diff --git a/kernel/sched/cpupri.h b/kernel/sched/cpupri.h
index f6d75617349..6b033347fdf 100644
--- a/kernel/sched/cpupri.h
+++ b/kernel/sched/cpupri.h
@@ -17,7 +17,7 @@ struct cpupri_vec {
struct cpupri {
struct cpupri_vec pri_to_cpu[CPUPRI_NR_PRIORITIES];
- int cpu_to_pri[NR_CPUS];
+ int *cpu_to_pri;
};
#ifdef CONFIG_SMP
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-29 23:43:40 +0000