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-rw-r--r--kernel/irq/manage.c118
1 files changed, 64 insertions, 54 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 89a3ea82569..ea0c6c2ae6f 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -7,6 +7,8 @@
* This file contains driver APIs to the irq subsystem.
*/
+#define pr_fmt(fmt) "genirq: " fmt
+
#include <linux/irq.h>
#include <linux/kthread.h>
#include <linux/module.h>
@@ -14,6 +16,7 @@
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/sched.h>
+#include <linux/task_work.h>
#include "internals.h"
@@ -566,7 +569,7 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
* flow-types?
*/
pr_debug("No set_type function for IRQ %d (%s)\n", irq,
- chip ? (chip->name ? : "unknown") : "unknown");
+ chip ? (chip->name ? : "unknown") : "unknown");
return 0;
}
@@ -600,7 +603,7 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
ret = 0;
break;
default:
- pr_err("setting trigger mode %lu for irq %u failed (%pF)\n",
+ pr_err("Setting trigger mode %lu for irq %u failed (%pF)\n",
flags, irq, chip->irq_set_type);
}
if (unmask)
@@ -773,11 +776,39 @@ static void wake_threads_waitq(struct irq_desc *desc)
wake_up(&desc->wait_for_threads);
}
+static void irq_thread_dtor(struct task_work *unused)
+{
+ struct task_struct *tsk = current;
+ struct irq_desc *desc;
+ struct irqaction *action;
+
+ if (WARN_ON_ONCE(!(current->flags & PF_EXITING)))
+ return;
+
+ action = kthread_data(tsk);
+
+ pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
+ tsk->comm ? tsk->comm : "", tsk->pid, action->irq);
+
+
+ desc = irq_to_desc(action->irq);
+ /*
+ * If IRQTF_RUNTHREAD is set, we need to decrement
+ * desc->threads_active and wake possible waiters.
+ */
+ if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
+ wake_threads_waitq(desc);
+
+ /* Prevent a stale desc->threads_oneshot */
+ irq_finalize_oneshot(desc, action);
+}
+
/*
* Interrupt handler thread
*/
static int irq_thread(void *data)
{
+ struct task_work on_exit_work;
static const struct sched_param param = {
.sched_priority = MAX_USER_RT_PRIO/2,
};
@@ -793,7 +824,9 @@ static int irq_thread(void *data)
handler_fn = irq_thread_fn;
sched_setscheduler(current, SCHED_FIFO, &param);
- current->irq_thread = 1;
+
+ init_task_work(&on_exit_work, irq_thread_dtor, NULL);
+ task_work_add(current, &on_exit_work, false);
while (!irq_wait_for_interrupt(action)) {
irqreturn_t action_ret;
@@ -815,45 +848,11 @@ static int irq_thread(void *data)
* cannot touch the oneshot mask at this point anymore as
* __setup_irq() might have given out currents thread_mask
* again.
- *
- * Clear irq_thread. Otherwise exit_irq_thread() would make
- * fuzz about an active irq thread going into nirvana.
*/
- current->irq_thread = 0;
+ task_work_cancel(current, irq_thread_dtor);
return 0;
}
-/*
- * Called from do_exit()
- */
-void exit_irq_thread(void)
-{
- struct task_struct *tsk = current;
- struct irq_desc *desc;
- struct irqaction *action;
-
- if (!tsk->irq_thread)
- return;
-
- action = kthread_data(tsk);
-
- printk(KERN_ERR
- "exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
- tsk->comm ? tsk->comm : "", tsk->pid, action->irq);
-
- desc = irq_to_desc(action->irq);
-
- /*
- * If IRQTF_RUNTHREAD is set, we need to decrement
- * desc->threads_active and wake possible waiters.
- */
- if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
- wake_threads_waitq(desc);
-
- /* Prevent a stale desc->threads_oneshot */
- irq_finalize_oneshot(desc, action);
-}
-
static void irq_setup_forced_threading(struct irqaction *new)
{
if (!force_irqthreads)
@@ -878,7 +877,6 @@ static int
__setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
{
struct irqaction *old, **old_ptr;
- const char *old_name = NULL;
unsigned long flags, thread_mask = 0;
int ret, nested, shared = 0;
cpumask_var_t mask;
@@ -972,10 +970,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
*/
if (!((old->flags & new->flags) & IRQF_SHARED) ||
((old->flags ^ new->flags) & IRQF_TRIGGER_MASK) ||
- ((old->flags ^ new->flags) & IRQF_ONESHOT)) {
- old_name = old->name;
+ ((old->flags ^ new->flags) & IRQF_ONESHOT))
goto mismatch;
- }
/* All handlers must agree on per-cpuness */
if ((old->flags & IRQF_PERCPU) !=
@@ -1031,6 +1027,27 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
* all existing action->thread_mask bits.
*/
new->thread_mask = 1 << ffz(thread_mask);
+
+ } else if (new->handler == irq_default_primary_handler) {
+ /*
+ * The interrupt was requested with handler = NULL, so
+ * we use the default primary handler for it. But it
+ * does not have the oneshot flag set. In combination
+ * with level interrupts this is deadly, because the
+ * default primary handler just wakes the thread, then
+ * the irq lines is reenabled, but the device still
+ * has the level irq asserted. Rinse and repeat....
+ *
+ * While this works for edge type interrupts, we play
+ * it safe and reject unconditionally because we can't
+ * say for sure which type this interrupt really
+ * has. The type flags are unreliable as the
+ * underlying chip implementation can override them.
+ */
+ pr_err("Threaded irq requested with handler=NULL and !ONESHOT for irq %d\n",
+ irq);
+ ret = -EINVAL;
+ goto out_mask;
}
if (!shared) {
@@ -1078,7 +1095,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
if (nmsk != omsk)
/* hope the handler works with current trigger mode */
- pr_warning("IRQ %d uses trigger mode %u; requested %u\n",
+ pr_warning("irq %d uses trigger mode %u; requested %u\n",
irq, nmsk, omsk);
}
@@ -1115,14 +1132,13 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
return 0;
mismatch:
-#ifdef CONFIG_DEBUG_SHIRQ
if (!(new->flags & IRQF_PROBE_SHARED)) {
- printk(KERN_ERR "IRQ handler type mismatch for IRQ %d\n", irq);
- if (old_name)
- printk(KERN_ERR "current handler: %s\n", old_name);
+ pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
+ irq, new->flags, new->name, old->flags, old->name);
+#ifdef CONFIG_DEBUG_SHIRQ
dump_stack();
- }
#endif
+ }
ret = -EBUSY;
out_mask:
@@ -1204,12 +1220,6 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
/* Found it - now remove it from the list of entries: */
*action_ptr = action->next;
- /* Currently used only by UML, might disappear one day: */
-#ifdef CONFIG_IRQ_RELEASE_METHOD
- if (desc->irq_data.chip->release)
- desc->irq_data.chip->release(irq, dev_id);
-#endif
-
/* If this was the last handler, shut down the IRQ line: */
if (!desc->action)
irq_shutdown(desc);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-05 02:12:15 +0000