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-rw-r--r--kernel/debug/gdbstub.c13
-rw-r--r--kernel/dma/direct.c2
-rw-r--r--kernel/dma/pool.c91
-rw-r--r--kernel/events/uprobes.c2
-rw-r--r--kernel/irq/manage.c37
-rw-r--r--kernel/sched/core.c74
-rw-r--r--kernel/sched/fair.c15
-rw-r--r--kernel/time/timer.c21
8 files changed, 193 insertions, 62 deletions
diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c
index 61774aec46b4..a790026e42d0 100644
--- a/kernel/debug/gdbstub.c
+++ b/kernel/debug/gdbstub.c
@@ -792,6 +792,19 @@ static void gdb_cmd_query(struct kgdb_state *ks)
}
break;
#endif
+#ifdef CONFIG_HAVE_ARCH_KGDB_QXFER_PKT
+ case 'S':
+ if (!strncmp(remcom_in_buffer, "qSupported:", 11))
+ strcpy(remcom_out_buffer, kgdb_arch_gdb_stub_feature);
+ break;
+ case 'X':
+ if (!strncmp(remcom_in_buffer, "qXfer:", 6))
+ kgdb_arch_handle_qxfer_pkt(remcom_in_buffer,
+ remcom_out_buffer);
+ break;
+#endif
+ default:
+ break;
}
}
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 95866b647581..67f060b86a73 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -70,7 +70,7 @@ gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask,
return 0;
}
-static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
+bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
{
return phys_to_dma_direct(dev, phys) + size - 1 <=
min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c
index 39ca26fa41b5..6bc74a2d5127 100644
--- a/kernel/dma/pool.c
+++ b/kernel/dma/pool.c
@@ -6,7 +6,6 @@
#include <linux/debugfs.h>
#include <linux/dma-direct.h>
#include <linux/dma-noncoherent.h>
-#include <linux/dma-contiguous.h>
#include <linux/init.h>
#include <linux/genalloc.h>
#include <linux/set_memory.h>
@@ -69,12 +68,7 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size,
do {
pool_size = 1 << (PAGE_SHIFT + order);
-
- if (dev_get_cma_area(NULL))
- page = dma_alloc_from_contiguous(NULL, 1 << order,
- order, false);
- else
- page = alloc_pages(gfp, order);
+ page = alloc_pages(gfp, order);
} while (!page && order-- > 0);
if (!page)
goto out;
@@ -118,8 +112,7 @@ remove_mapping:
dma_common_free_remap(addr, pool_size);
#endif
free_page: __maybe_unused
- if (!dma_release_from_contiguous(NULL, page, 1 << order))
- __free_pages(page, order);
+ __free_pages(page, order);
out:
return ret;
}
@@ -203,7 +196,7 @@ static int __init dma_atomic_pool_init(void)
}
postcore_initcall(dma_atomic_pool_init);
-static inline struct gen_pool *dev_to_pool(struct device *dev)
+static inline struct gen_pool *dma_guess_pool_from_device(struct device *dev)
{
u64 phys_mask;
gfp_t gfp;
@@ -217,51 +210,79 @@ static inline struct gen_pool *dev_to_pool(struct device *dev)
return atomic_pool_kernel;
}
-static bool dma_in_atomic_pool(struct device *dev, void *start, size_t size)
+static inline struct gen_pool *dma_get_safer_pool(struct gen_pool *bad_pool)
+{
+ if (bad_pool == atomic_pool_kernel)
+ return atomic_pool_dma32 ? : atomic_pool_dma;
+
+ if (bad_pool == atomic_pool_dma32)
+ return atomic_pool_dma;
+
+ return NULL;
+}
+
+static inline struct gen_pool *dma_guess_pool(struct device *dev,
+ struct gen_pool *bad_pool)
{
- struct gen_pool *pool = dev_to_pool(dev);
+ if (bad_pool)
+ return dma_get_safer_pool(bad_pool);
- if (unlikely(!pool))
- return false;
- return gen_pool_has_addr(pool, (unsigned long)start, size);
+ return dma_guess_pool_from_device(dev);
}
void *dma_alloc_from_pool(struct device *dev, size_t size,
struct page **ret_page, gfp_t flags)
{
- struct gen_pool *pool = dev_to_pool(dev);
- unsigned long val;
+ struct gen_pool *pool = NULL;
+ unsigned long val = 0;
void *ptr = NULL;
-
- if (!pool) {
- WARN(1, "%pGg atomic pool not initialised!\n", &flags);
- return NULL;
+ phys_addr_t phys;
+
+ while (1) {
+ pool = dma_guess_pool(dev, pool);
+ if (!pool) {
+ WARN(1, "Failed to get suitable pool for %s\n",
+ dev_name(dev));
+ break;
+ }
+
+ val = gen_pool_alloc(pool, size);
+ if (!val)
+ continue;
+
+ phys = gen_pool_virt_to_phys(pool, val);
+ if (dma_coherent_ok(dev, phys, size))
+ break;
+
+ gen_pool_free(pool, val, size);
+ val = 0;
}
- val = gen_pool_alloc(pool, size);
- if (likely(val)) {
- phys_addr_t phys = gen_pool_virt_to_phys(pool, val);
+ if (val) {
*ret_page = pfn_to_page(__phys_to_pfn(phys));
ptr = (void *)val;
memset(ptr, 0, size);
- } else {
- WARN_ONCE(1, "DMA coherent pool depleted, increase size "
- "(recommended min coherent_pool=%zuK)\n",
- gen_pool_size(pool) >> 9);
+
+ if (gen_pool_avail(pool) < atomic_pool_size)
+ schedule_work(&atomic_pool_work);
}
- if (gen_pool_avail(pool) < atomic_pool_size)
- schedule_work(&atomic_pool_work);
return ptr;
}
bool dma_free_from_pool(struct device *dev, void *start, size_t size)
{
- struct gen_pool *pool = dev_to_pool(dev);
+ struct gen_pool *pool = NULL;
+
+ while (1) {
+ pool = dma_guess_pool(dev, pool);
+ if (!pool)
+ return false;
- if (!dma_in_atomic_pool(dev, start, size))
- return false;
- gen_pool_free(pool, (unsigned long)start, size);
- return true;
+ if (gen_pool_has_addr(pool, (unsigned long)start, size)) {
+ gen_pool_free(pool, (unsigned long)start, size);
+ return true;
+ }
+ }
}
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index bb0862873dba..5f8b0c52fd2e 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -2199,7 +2199,7 @@ static void handle_swbp(struct pt_regs *regs)
if (!uprobe) {
if (is_swbp > 0) {
/* No matching uprobe; signal SIGTRAP. */
- send_sig(SIGTRAP, current, 0);
+ force_sig(SIGTRAP);
} else {
/*
* Either we raced with uprobe_unregister() or we can't
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 761911168438..2a9fec53e159 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -195,9 +195,9 @@ void irq_set_thread_affinity(struct irq_desc *desc)
set_bit(IRQTF_AFFINITY, &action->thread_flags);
}
+#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
static void irq_validate_effective_affinity(struct irq_data *data)
{
-#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
const struct cpumask *m = irq_data_get_effective_affinity_mask(data);
struct irq_chip *chip = irq_data_get_irq_chip(data);
@@ -205,9 +205,19 @@ static void irq_validate_effective_affinity(struct irq_data *data)
return;
pr_warn_once("irq_chip %s did not update eff. affinity mask of irq %u\n",
chip->name, data->irq);
-#endif
}
+static inline void irq_init_effective_affinity(struct irq_data *data,
+ const struct cpumask *mask)
+{
+ cpumask_copy(irq_data_get_effective_affinity_mask(data), mask);
+}
+#else
+static inline void irq_validate_effective_affinity(struct irq_data *data) { }
+static inline void irq_init_effective_affinity(struct irq_data *data,
+ const struct cpumask *mask) { }
+#endif
+
int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
bool force)
{
@@ -304,6 +314,26 @@ static int irq_try_set_affinity(struct irq_data *data,
return ret;
}
+static bool irq_set_affinity_deactivated(struct irq_data *data,
+ const struct cpumask *mask, bool force)
+{
+ struct irq_desc *desc = irq_data_to_desc(data);
+
+ /*
+ * If the interrupt is not yet activated, just store the affinity
+ * mask and do not call the chip driver at all. On activation the
+ * driver has to make sure anyway that the interrupt is in a
+ * useable state so startup works.
+ */
+ if (!IS_ENABLED(CONFIG_IRQ_DOMAIN_HIERARCHY) || irqd_is_activated(data))
+ return false;
+
+ cpumask_copy(desc->irq_common_data.affinity, mask);
+ irq_init_effective_affinity(data, mask);
+ irqd_set(data, IRQD_AFFINITY_SET);
+ return true;
+}
+
int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
bool force)
{
@@ -314,6 +344,9 @@ int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
if (!chip || !chip->irq_set_affinity)
return -EINVAL;
+ if (irq_set_affinity_deactivated(data, mask, force))
+ return 0;
+
if (irq_can_move_pcntxt(data) && !irqd_is_setaffinity_pending(data)) {
ret = irq_try_set_affinity(data, mask, force);
} else {
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index ca5db40392d4..2142c6767682 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1311,9 +1311,6 @@ static inline void dequeue_task(struct rq *rq, struct task_struct *p, int flags)
void activate_task(struct rq *rq, struct task_struct *p, int flags)
{
- if (task_contributes_to_load(p))
- rq->nr_uninterruptible--;
-
enqueue_task(rq, p, flags);
p->on_rq = TASK_ON_RQ_QUEUED;
@@ -1323,9 +1320,6 @@ void deactivate_task(struct rq *rq, struct task_struct *p, int flags)
{
p->on_rq = (flags & DEQUEUE_SLEEP) ? 0 : TASK_ON_RQ_MIGRATING;
- if (task_contributes_to_load(p))
- rq->nr_uninterruptible++;
-
dequeue_task(rq, p, flags);
}
@@ -2236,10 +2230,10 @@ ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags,
lockdep_assert_held(&rq->lock);
-#ifdef CONFIG_SMP
if (p->sched_contributes_to_load)
rq->nr_uninterruptible--;
+#ifdef CONFIG_SMP
if (wake_flags & WF_MIGRATED)
en_flags |= ENQUEUE_MIGRATED;
#endif
@@ -2583,7 +2577,7 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
* A similar smb_rmb() lives in try_invoke_on_locked_down_task().
*/
smp_rmb();
- if (p->on_rq && ttwu_remote(p, wake_flags))
+ if (READ_ONCE(p->on_rq) && ttwu_remote(p, wake_flags))
goto unlock;
if (p->in_iowait) {
@@ -2592,9 +2586,6 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
}
#ifdef CONFIG_SMP
- p->sched_contributes_to_load = !!task_contributes_to_load(p);
- p->state = TASK_WAKING;
-
/*
* Ensure we load p->on_cpu _after_ p->on_rq, otherwise it would be
* possible to, falsely, observe p->on_cpu == 0.
@@ -2613,8 +2604,20 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
*
* Pairs with the LOCK+smp_mb__after_spinlock() on rq->lock in
* __schedule(). See the comment for smp_mb__after_spinlock().
+ *
+ * Form a control-dep-acquire with p->on_rq == 0 above, to ensure
+ * schedule()'s deactivate_task() has 'happened' and p will no longer
+ * care about it's own p->state. See the comment in __schedule().
*/
- smp_rmb();
+ smp_acquire__after_ctrl_dep();
+
+ /*
+ * We're doing the wakeup (@success == 1), they did a dequeue (p->on_rq
+ * == 0), which means we need to do an enqueue, change p->state to
+ * TASK_WAKING such that we can unlock p->pi_lock before doing the
+ * enqueue, such as ttwu_queue_wakelist().
+ */
+ p->state = TASK_WAKING;
/*
* If the owning (remote) CPU is still in the middle of schedule() with
@@ -2962,6 +2965,7 @@ int sched_fork(unsigned long clone_flags, struct task_struct *p)
* Silence PROVE_RCU.
*/
raw_spin_lock_irqsave(&p->pi_lock, flags);
+ rseq_migrate(p);
/*
* We're setting the CPU for the first time, we don't migrate,
* so use __set_task_cpu().
@@ -3026,6 +3030,7 @@ void wake_up_new_task(struct task_struct *p)
* as we're not fully set-up yet.
*/
p->recent_used_cpu = task_cpu(p);
+ rseq_migrate(p);
__set_task_cpu(p, select_task_rq(p, task_cpu(p), SD_BALANCE_FORK, 0));
#endif
rq = __task_rq_lock(p, &rf);
@@ -4097,6 +4102,7 @@ static void __sched notrace __schedule(bool preempt)
{
struct task_struct *prev, *next;
unsigned long *switch_count;
+ unsigned long prev_state;
struct rq_flags rf;
struct rq *rq;
int cpu;
@@ -4116,9 +4122,16 @@ static void __sched notrace __schedule(bool preempt)
/*
* Make sure that signal_pending_state()->signal_pending() below
* can't be reordered with __set_current_state(TASK_INTERRUPTIBLE)
- * done by the caller to avoid the race with signal_wake_up().
+ * done by the caller to avoid the race with signal_wake_up():
+ *
+ * __set_current_state(@state) signal_wake_up()
+ * schedule() set_tsk_thread_flag(p, TIF_SIGPENDING)
+ * wake_up_state(p, state)
+ * LOCK rq->lock LOCK p->pi_state
+ * smp_mb__after_spinlock() smp_mb__after_spinlock()
+ * if (signal_pending_state()) if (p->state & @state)
*
- * The membarrier system call requires a full memory barrier
+ * Also, the membarrier system call requires a full memory barrier
* after coming from user-space, before storing to rq->curr.
*/
rq_lock(rq, &rf);
@@ -4129,10 +4142,38 @@ static void __sched notrace __schedule(bool preempt)
update_rq_clock(rq);
switch_count = &prev->nivcsw;
- if (!preempt && prev->state) {
- if (signal_pending_state(prev->state, prev)) {
+
+ /*
+ * We must load prev->state once (task_struct::state is volatile), such
+ * that:
+ *
+ * - we form a control dependency vs deactivate_task() below.
+ * - ptrace_{,un}freeze_traced() can change ->state underneath us.
+ */
+ prev_state = prev->state;
+ if (!preempt && prev_state) {
+ if (signal_pending_state(prev_state, prev)) {
prev->state = TASK_RUNNING;
} else {
+ prev->sched_contributes_to_load =
+ (prev_state & TASK_UNINTERRUPTIBLE) &&
+ !(prev_state & TASK_NOLOAD) &&
+ !(prev->flags & PF_FROZEN);
+
+ if (prev->sched_contributes_to_load)
+ rq->nr_uninterruptible++;
+
+ /*
+ * __schedule() ttwu()
+ * prev_state = prev->state; if (p->on_rq && ...)
+ * if (prev_state) goto out;
+ * p->on_rq = 0; smp_acquire__after_ctrl_dep();
+ * p->state = TASK_WAKING
+ *
+ * Where __schedule() and ttwu() have matching control dependencies.
+ *
+ * After this, schedule() must not care about p->state any more.
+ */
deactivate_task(rq, prev, DEQUEUE_SLEEP | DEQUEUE_NOCLOCK);
if (prev->in_iowait) {
@@ -4444,6 +4485,7 @@ asmlinkage __visible void __sched preempt_schedule_irq(void)
int default_wake_function(wait_queue_entry_t *curr, unsigned mode, int wake_flags,
void *key)
{
+ WARN_ON_ONCE(IS_ENABLED(CONFIG_SCHED_DEBUG) && wake_flags & ~WF_SYNC);
return try_to_wake_up(curr->private, mode, wake_flags);
}
EXPORT_SYMBOL(default_wake_function);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 658aa7a2ae6f..04fa8dbcfa4d 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4039,7 +4039,11 @@ static inline void update_misfit_status(struct task_struct *p, struct rq *rq)
return;
}
- rq->misfit_task_load = task_h_load(p);
+ /*
+ * Make sure that misfit_task_load will not be null even if
+ * task_h_load() returns 0.
+ */
+ rq->misfit_task_load = max_t(unsigned long, task_h_load(p), 1);
}
#else /* CONFIG_SMP */
@@ -7638,7 +7642,14 @@ static int detach_tasks(struct lb_env *env)
switch (env->migration_type) {
case migrate_load:
- load = task_h_load(p);
+ /*
+ * Depending of the number of CPUs and tasks and the
+ * cgroup hierarchy, task_h_load() can return a null
+ * value. Make sure that env->imbalance decreases
+ * otherwise detach_tasks() will stop only after
+ * detaching up to loop_max tasks.
+ */
+ load = max_t(unsigned long, task_h_load(p), 1);
if (sched_feat(LB_MIN) &&
load < 16 && !env->sd->nr_balance_failed)
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 398e6eadb861..df1ff803acc4 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -521,8 +521,8 @@ static int calc_wheel_index(unsigned long expires, unsigned long clk)
* Force expire obscene large timeouts to expire at the
* capacity limit of the wheel.
*/
- if (expires >= WHEEL_TIMEOUT_CUTOFF)
- expires = WHEEL_TIMEOUT_MAX;
+ if (delta >= WHEEL_TIMEOUT_CUTOFF)
+ expires = clk + WHEEL_TIMEOUT_MAX;
idx = calc_index(expires, LVL_DEPTH - 1);
}
@@ -584,7 +584,15 @@ trigger_dyntick_cpu(struct timer_base *base, struct timer_list *timer)
* Set the next expiry time and kick the CPU so it can reevaluate the
* wheel:
*/
- base->next_expiry = timer->expires;
+ if (time_before(timer->expires, base->clk)) {
+ /*
+ * Prevent from forward_timer_base() moving the base->clk
+ * backward
+ */
+ base->next_expiry = base->clk;
+ } else {
+ base->next_expiry = timer->expires;
+ }
wake_up_nohz_cpu(base->cpu);
}
@@ -896,10 +904,13 @@ static inline void forward_timer_base(struct timer_base *base)
* If the next expiry value is > jiffies, then we fast forward to
* jiffies otherwise we forward to the next expiry value.
*/
- if (time_after(base->next_expiry, jnow))
+ if (time_after(base->next_expiry, jnow)) {
base->clk = jnow;
- else
+ } else {
+ if (WARN_ON_ONCE(time_before(base->next_expiry, base->clk)))
+ return;
base->clk = base->next_expiry;
+ }
#endif
}