Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 9dbdcca..1753486 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -13,6 +13,7 @@
#include <linux/module.h>
#include <linux/random.h>
#include <linux/interrupt.h>
+#include <linux/irqdomain.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/sched/rt.h>
@@ -22,7 +23,7 @@
#include "internals.h"
-#ifdef CONFIG_IRQ_FORCED_THREADING
+#if defined(CONFIG_IRQ_FORCED_THREADING) && !defined(CONFIG_PREEMPT_RT)
__read_mostly bool force_irqthreads;
EXPORT_SYMBOL_GPL(force_irqthreads);
@@ -34,8 +35,9 @@
early_param("threadirqs", setup_forced_irqthreads);
#endif
-static void __synchronize_hardirq(struct irq_desc *desc)
+static void __synchronize_hardirq(struct irq_desc *desc, bool sync_chip)
{
+ struct irq_data *irqd = irq_desc_get_irq_data(desc);
bool inprogress;
do {
@@ -51,6 +53,20 @@
/* Ok, that indicated we're done: double-check carefully. */
raw_spin_lock_irqsave(&desc->lock, flags);
inprogress = irqd_irq_inprogress(&desc->irq_data);
+
+ /*
+ * If requested and supported, check at the chip whether it
+ * is in flight at the hardware level, i.e. already pending
+ * in a CPU and waiting for service and acknowledge.
+ */
+ if (!inprogress && sync_chip) {
+ /*
+ * Ignore the return code. inprogress is only updated
+ * when the chip supports it.
+ */
+ __irq_get_irqchip_state(irqd, IRQCHIP_STATE_ACTIVE,
+ &inprogress);
+ }
raw_spin_unlock_irqrestore(&desc->lock, flags);
/* Oops, that failed? */
@@ -73,13 +89,18 @@
* Returns: false if a threaded handler is active.
*
* This function may be called - with care - from IRQ context.
+ *
+ * It does not check whether there is an interrupt in flight at the
+ * hardware level, but not serviced yet, as this might deadlock when
+ * called with interrupts disabled and the target CPU of the interrupt
+ * is the current CPU.
*/
bool synchronize_hardirq(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
if (desc) {
- __synchronize_hardirq(desc);
+ __synchronize_hardirq(desc, false);
return !atomic_read(&desc->threads_active);
}
@@ -95,14 +116,19 @@
* to complete before returning. If you use this function while
* holding a resource the IRQ handler may need you will deadlock.
*
- * This function may be called - with care - from IRQ context.
+ * Can only be called from preemptible code as it might sleep when
+ * an interrupt thread is associated to @irq.
+ *
+ * It optionally makes sure (when the irq chip supports that method)
+ * that the interrupt is not pending in any CPU and waiting for
+ * service.
*/
void synchronize_irq(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
if (desc) {
- __synchronize_hardirq(desc);
+ __synchronize_hardirq(desc, true);
/*
* We made sure that no hardirq handler is
* running. Now verify that no threaded handlers are
@@ -196,6 +222,7 @@
case IRQ_SET_MASK_OK:
case IRQ_SET_MASK_OK_DONE:
cpumask_copy(desc->irq_common_data.affinity, mask);
+ /* fall through */
case IRQ_SET_MASK_OK_NOCOPY:
irq_validate_effective_affinity(data);
irq_set_thread_affinity(desc);
@@ -341,7 +368,7 @@
/* The release function is promised process context */
might_sleep();
- if (!desc)
+ if (!desc || desc->istate & IRQS_NMI)
return -EINVAL;
/* Complete initialisation of *notify */
@@ -356,8 +383,10 @@
desc->affinity_notify = notify;
raw_spin_unlock_irqrestore(&desc->lock, flags);
- if (old_notify)
+ if (old_notify) {
+ cancel_work_sync(&old_notify->work);
kref_put(&old_notify->kref, old_notify->release);
+ }
return 0;
}
@@ -393,6 +422,9 @@
}
cpumask_and(&mask, cpu_online_mask, set);
+ if (cpumask_empty(&mask))
+ cpumask_copy(&mask, cpu_online_mask);
+
if (node != NUMA_NO_NODE) {
const struct cpumask *nodemask = cpumask_of_node(node);
@@ -550,6 +582,21 @@
}
EXPORT_SYMBOL_GPL(disable_hardirq);
+/**
+ * disable_nmi_nosync - disable an nmi without waiting
+ * @irq: Interrupt to disable
+ *
+ * Disable the selected interrupt line. Disables and enables are
+ * nested.
+ * The interrupt to disable must have been requested through request_nmi.
+ * Unlike disable_nmi(), this function does not ensure existing
+ * instances of the IRQ handler have completed before returning.
+ */
+void disable_nmi_nosync(unsigned int irq)
+{
+ disable_irq_nosync(irq);
+}
+
void __enable_irq(struct irq_desc *desc)
{
switch (desc->depth) {
@@ -606,6 +653,20 @@
}
EXPORT_SYMBOL(enable_irq);
+/**
+ * enable_nmi - enable handling of an nmi
+ * @irq: Interrupt to enable
+ *
+ * The interrupt to enable must have been requested through request_nmi.
+ * Undoes the effect of one call to disable_nmi(). If this
+ * matches the last disable, processing of interrupts on this
+ * IRQ line is re-enabled.
+ */
+void enable_nmi(unsigned int irq)
+{
+ enable_irq(irq);
+}
+
static int set_irq_wake_real(unsigned int irq, unsigned int on)
{
struct irq_desc *desc = irq_to_desc(irq);
@@ -641,6 +702,12 @@
if (!desc)
return -EINVAL;
+ /* Don't use NMIs as wake up interrupts please */
+ if (desc->istate & IRQS_NMI) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
/* wakeup-capable irqs can be shared between drivers that
* don't need to have the same sleep mode behaviors.
*/
@@ -663,6 +730,8 @@
irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
}
}
+
+out_unlock:
irq_put_desc_busunlock(desc, flags);
return ret;
}
@@ -723,6 +792,7 @@
case IRQ_SET_MASK_OK_DONE:
irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK);
irqd_set(&desc->irq_data, flags);
+ /* fall through */
case IRQ_SET_MASK_OK_NOCOPY:
flags = irqd_get_trigger_type(&desc->irq_data);
@@ -737,7 +807,7 @@
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 (%pS)\n",
flags, irq_desc_get_irq(desc), chip->irq_set_type);
}
if (unmask)
@@ -915,7 +985,7 @@
#endif
/*
- * Interrupts which are not explicitely requested as threaded
+ * Interrupts which are not explicitly requested as threaded
* interrupts rely on the implicit bh/preempt disable of the hard irq
* context. So we need to disable bh here to avoid deadlocks and other
* side effects.
@@ -1125,6 +1195,39 @@
c->irq_release_resources(d);
}
+static bool irq_supports_nmi(struct irq_desc *desc)
+{
+ struct irq_data *d = irq_desc_get_irq_data(desc);
+
+#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
+ /* Only IRQs directly managed by the root irqchip can be set as NMI */
+ if (d->parent_data)
+ return false;
+#endif
+ /* Don't support NMIs for chips behind a slow bus */
+ if (d->chip->irq_bus_lock || d->chip->irq_bus_sync_unlock)
+ return false;
+
+ return d->chip->flags & IRQCHIP_SUPPORTS_NMI;
+}
+
+static int irq_nmi_setup(struct irq_desc *desc)
+{
+ struct irq_data *d = irq_desc_get_irq_data(desc);
+ struct irq_chip *c = d->chip;
+
+ return c->irq_nmi_setup ? c->irq_nmi_setup(d) : -EINVAL;
+}
+
+static void irq_nmi_teardown(struct irq_desc *desc)
+{
+ struct irq_data *d = irq_desc_get_irq_data(desc);
+ struct irq_chip *c = d->chip;
+
+ if (c->irq_nmi_teardown)
+ c->irq_nmi_teardown(d);
+}
+
static int
setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
{
@@ -1152,8 +1255,7 @@
* the thread dies to avoid that the interrupt code
* references an already freed task_struct.
*/
- get_task_struct(t);
- new->thread = t;
+ new->thread = get_task_struct(t);
/*
* Tell the thread to set its affinity. This is
* important for shared interrupt handlers as we do
@@ -1299,9 +1401,17 @@
* fields must have IRQF_SHARED set and the bits which
* set the trigger type must match. Also all must
* agree on ONESHOT.
+ * Interrupt lines used for NMIs cannot be shared.
*/
unsigned int oldtype;
+ if (desc->istate & IRQS_NMI) {
+ pr_err("Invalid attempt to share NMI for %s (irq %d) on irqchip %s.\n",
+ new->name, irq, desc->irq_data.chip->name);
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
/*
* If nobody did set the configuration before, inherit
* the one provided by the requester.
@@ -1614,6 +1724,7 @@
/* If this was the last handler, shut down the IRQ line: */
if (!desc->action) {
irq_settings_clr_disable_unlazy(desc);
+ /* Only shutdown. Deactivate after synchronize_hardirq() */
irq_shutdown(desc);
}
@@ -1642,8 +1753,12 @@
unregister_handler_proc(irq, action);
- /* Make sure it's not being used on another CPU: */
- synchronize_hardirq(irq);
+ /*
+ * Make sure it's not being used on another CPU and if the chip
+ * supports it also make sure that there is no (not yet serviced)
+ * interrupt in flight at the hardware level.
+ */
+ __synchronize_hardirq(desc, true);
#ifdef CONFIG_DEBUG_SHIRQ
/*
@@ -1683,6 +1798,14 @@
* require it to deallocate resources over the slow bus.
*/
chip_bus_lock(desc);
+ /*
+ * There is no interrupt on the fly anymore. Deactivate it
+ * completely.
+ */
+ raw_spin_lock_irqsave(&desc->lock, flags);
+ irq_domain_deactivate_irq(&desc->irq_data);
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
irq_release_resources(desc);
chip_bus_sync_unlock(desc);
irq_remove_timings(desc);
@@ -1753,6 +1876,59 @@
}
EXPORT_SYMBOL(free_irq);
+/* This function must be called with desc->lock held */
+static const void *__cleanup_nmi(unsigned int irq, struct irq_desc *desc)
+{
+ const char *devname = NULL;
+
+ desc->istate &= ~IRQS_NMI;
+
+ if (!WARN_ON(desc->action == NULL)) {
+ irq_pm_remove_action(desc, desc->action);
+ devname = desc->action->name;
+ unregister_handler_proc(irq, desc->action);
+
+ kfree(desc->action);
+ desc->action = NULL;
+ }
+
+ irq_settings_clr_disable_unlazy(desc);
+ irq_shutdown_and_deactivate(desc);
+
+ irq_release_resources(desc);
+
+ irq_chip_pm_put(&desc->irq_data);
+ module_put(desc->owner);
+
+ return devname;
+}
+
+const void *free_nmi(unsigned int irq, void *dev_id)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+ unsigned long flags;
+ const void *devname;
+
+ if (!desc || WARN_ON(!(desc->istate & IRQS_NMI)))
+ return NULL;
+
+ if (WARN_ON(irq_settings_is_per_cpu_devid(desc)))
+ return NULL;
+
+ /* NMI still enabled */
+ if (WARN_ON(desc->depth == 0))
+ disable_nmi_nosync(irq);
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+
+ irq_nmi_teardown(desc);
+ devname = __cleanup_nmi(irq, desc);
+
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
+ return devname;
+}
+
/**
* request_threaded_irq - allocate an interrupt line
* @irq: Interrupt line to allocate
@@ -1922,6 +2098,101 @@
}
EXPORT_SYMBOL_GPL(request_any_context_irq);
+/**
+ * request_nmi - allocate an interrupt line for NMI delivery
+ * @irq: Interrupt line to allocate
+ * @handler: Function to be called when the IRQ occurs.
+ * Threaded handler for threaded interrupts.
+ * @irqflags: Interrupt type flags
+ * @name: An ascii name for the claiming device
+ * @dev_id: A cookie passed back to the handler function
+ *
+ * This call allocates interrupt resources and enables the
+ * interrupt line and IRQ handling. It sets up the IRQ line
+ * to be handled as an NMI.
+ *
+ * An interrupt line delivering NMIs cannot be shared and IRQ handling
+ * cannot be threaded.
+ *
+ * Interrupt lines requested for NMI delivering must produce per cpu
+ * interrupts and have auto enabling setting disabled.
+ *
+ * Dev_id must be globally unique. Normally the address of the
+ * device data structure is used as the cookie. Since the handler
+ * receives this value it makes sense to use it.
+ *
+ * If the interrupt line cannot be used to deliver NMIs, function
+ * will fail and return a negative value.
+ */
+int request_nmi(unsigned int irq, irq_handler_t handler,
+ unsigned long irqflags, const char *name, void *dev_id)
+{
+ struct irqaction *action;
+ struct irq_desc *desc;
+ unsigned long flags;
+ int retval;
+
+ if (irq == IRQ_NOTCONNECTED)
+ return -ENOTCONN;
+
+ /* NMI cannot be shared, used for Polling */
+ if (irqflags & (IRQF_SHARED | IRQF_COND_SUSPEND | IRQF_IRQPOLL))
+ return -EINVAL;
+
+ if (!(irqflags & IRQF_PERCPU))
+ return -EINVAL;
+
+ if (!handler)
+ return -EINVAL;
+
+ desc = irq_to_desc(irq);
+
+ if (!desc || irq_settings_can_autoenable(desc) ||
+ !irq_settings_can_request(desc) ||
+ WARN_ON(irq_settings_is_per_cpu_devid(desc)) ||
+ !irq_supports_nmi(desc))
+ return -EINVAL;
+
+ action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
+ if (!action)
+ return -ENOMEM;
+
+ action->handler = handler;
+ action->flags = irqflags | IRQF_NO_THREAD | IRQF_NOBALANCING;
+ action->name = name;
+ action->dev_id = dev_id;
+
+ retval = irq_chip_pm_get(&desc->irq_data);
+ if (retval < 0)
+ goto err_out;
+
+ retval = __setup_irq(irq, desc, action);
+ if (retval)
+ goto err_irq_setup;
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+
+ /* Setup NMI state */
+ desc->istate |= IRQS_NMI;
+ retval = irq_nmi_setup(desc);
+ if (retval) {
+ __cleanup_nmi(irq, desc);
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+ return -EINVAL;
+ }
+
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
+ return 0;
+
+err_irq_setup:
+ irq_chip_pm_put(&desc->irq_data);
+err_out:
+ kfree(action);
+
+ return retval;
+}
+
void enable_percpu_irq(unsigned int irq, unsigned int type)
{
unsigned int cpu = smp_processor_id();
@@ -1956,6 +2227,11 @@
}
EXPORT_SYMBOL_GPL(enable_percpu_irq);
+void enable_percpu_nmi(unsigned int irq, unsigned int type)
+{
+ enable_percpu_irq(irq, type);
+}
+
/**
* irq_percpu_is_enabled - Check whether the per cpu irq is enabled
* @irq: Linux irq number to check for
@@ -1995,6 +2271,11 @@
}
EXPORT_SYMBOL_GPL(disable_percpu_irq);
+void disable_percpu_nmi(unsigned int irq)
+{
+ disable_percpu_irq(irq);
+}
+
/*
* Internal function to unregister a percpu irqaction.
*/
@@ -2026,6 +2307,8 @@
/* Found it - now remove it from the list of entries: */
desc->action = NULL;
+ desc->istate &= ~IRQS_NMI;
+
raw_spin_unlock_irqrestore(&desc->lock, flags);
unregister_handler_proc(irq, action);
@@ -2079,6 +2362,19 @@
}
EXPORT_SYMBOL_GPL(free_percpu_irq);
+void free_percpu_nmi(unsigned int irq, void __percpu *dev_id)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ if (!desc || !irq_settings_is_per_cpu_devid(desc))
+ return;
+
+ if (WARN_ON(!(desc->istate & IRQS_NMI)))
+ return;
+
+ kfree(__free_percpu_irq(irq, dev_id));
+}
+
/**
* setup_percpu_irq - setup a per-cpu interrupt
* @irq: Interrupt line to setup
@@ -2169,6 +2465,180 @@
EXPORT_SYMBOL_GPL(__request_percpu_irq);
/**
+ * request_percpu_nmi - allocate a percpu interrupt line for NMI delivery
+ * @irq: Interrupt line to allocate
+ * @handler: Function to be called when the IRQ occurs.
+ * @name: An ascii name for the claiming device
+ * @dev_id: A percpu cookie passed back to the handler function
+ *
+ * This call allocates interrupt resources for a per CPU NMI. Per CPU NMIs
+ * have to be setup on each CPU by calling prepare_percpu_nmi() before
+ * being enabled on the same CPU by using enable_percpu_nmi().
+ *
+ * Dev_id must be globally unique. It is a per-cpu variable, and
+ * the handler gets called with the interrupted CPU's instance of
+ * that variable.
+ *
+ * Interrupt lines requested for NMI delivering should have auto enabling
+ * setting disabled.
+ *
+ * If the interrupt line cannot be used to deliver NMIs, function
+ * will fail returning a negative value.
+ */
+int request_percpu_nmi(unsigned int irq, irq_handler_t handler,
+ const char *name, void __percpu *dev_id)
+{
+ struct irqaction *action;
+ struct irq_desc *desc;
+ unsigned long flags;
+ int retval;
+
+ if (!handler)
+ return -EINVAL;
+
+ desc = irq_to_desc(irq);
+
+ if (!desc || !irq_settings_can_request(desc) ||
+ !irq_settings_is_per_cpu_devid(desc) ||
+ irq_settings_can_autoenable(desc) ||
+ !irq_supports_nmi(desc))
+ return -EINVAL;
+
+ /* The line cannot already be NMI */
+ if (desc->istate & IRQS_NMI)
+ return -EINVAL;
+
+ action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
+ if (!action)
+ return -ENOMEM;
+
+ action->handler = handler;
+ action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND | IRQF_NO_THREAD
+ | IRQF_NOBALANCING;
+ action->name = name;
+ action->percpu_dev_id = dev_id;
+
+ retval = irq_chip_pm_get(&desc->irq_data);
+ if (retval < 0)
+ goto err_out;
+
+ retval = __setup_irq(irq, desc, action);
+ if (retval)
+ goto err_irq_setup;
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+ desc->istate |= IRQS_NMI;
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
+ return 0;
+
+err_irq_setup:
+ irq_chip_pm_put(&desc->irq_data);
+err_out:
+ kfree(action);
+
+ return retval;
+}
+
+/**
+ * prepare_percpu_nmi - performs CPU local setup for NMI delivery
+ * @irq: Interrupt line to prepare for NMI delivery
+ *
+ * This call prepares an interrupt line to deliver NMI on the current CPU,
+ * before that interrupt line gets enabled with enable_percpu_nmi().
+ *
+ * As a CPU local operation, this should be called from non-preemptible
+ * context.
+ *
+ * If the interrupt line cannot be used to deliver NMIs, function
+ * will fail returning a negative value.
+ */
+int prepare_percpu_nmi(unsigned int irq)
+{
+ unsigned long flags;
+ struct irq_desc *desc;
+ int ret = 0;
+
+ WARN_ON(preemptible());
+
+ desc = irq_get_desc_lock(irq, &flags,
+ IRQ_GET_DESC_CHECK_PERCPU);
+ if (!desc)
+ return -EINVAL;
+
+ if (WARN(!(desc->istate & IRQS_NMI),
+ KERN_ERR "prepare_percpu_nmi called for a non-NMI interrupt: irq %u\n",
+ irq)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = irq_nmi_setup(desc);
+ if (ret) {
+ pr_err("Failed to setup NMI delivery: irq %u\n", irq);
+ goto out;
+ }
+
+out:
+ irq_put_desc_unlock(desc, flags);
+ return ret;
+}
+
+/**
+ * teardown_percpu_nmi - undoes NMI setup of IRQ line
+ * @irq: Interrupt line from which CPU local NMI configuration should be
+ * removed
+ *
+ * This call undoes the setup done by prepare_percpu_nmi().
+ *
+ * IRQ line should not be enabled for the current CPU.
+ *
+ * As a CPU local operation, this should be called from non-preemptible
+ * context.
+ */
+void teardown_percpu_nmi(unsigned int irq)
+{
+ unsigned long flags;
+ struct irq_desc *desc;
+
+ WARN_ON(preemptible());
+
+ desc = irq_get_desc_lock(irq, &flags,
+ IRQ_GET_DESC_CHECK_PERCPU);
+ if (!desc)
+ return;
+
+ if (WARN_ON(!(desc->istate & IRQS_NMI)))
+ goto out;
+
+ irq_nmi_teardown(desc);
+out:
+ irq_put_desc_unlock(desc, flags);
+}
+
+int __irq_get_irqchip_state(struct irq_data *data, enum irqchip_irq_state which,
+ bool *state)
+{
+ struct irq_chip *chip;
+ int err = -EINVAL;
+
+ do {
+ chip = irq_data_get_irq_chip(data);
+ if (chip->irq_get_irqchip_state)
+ break;
+#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
+ data = data->parent_data;
+#else
+ data = NULL;
+#endif
+ } while (data);
+
+ if (data)
+ err = chip->irq_get_irqchip_state(data, which, state);
+ return err;
+}
+
+/**
* irq_get_irqchip_state - returns the irqchip state of a interrupt.
* @irq: Interrupt line that is forwarded to a VM
* @which: One of IRQCHIP_STATE_* the caller wants to know about
@@ -2186,7 +2656,6 @@
{
struct irq_desc *desc;
struct irq_data *data;
- struct irq_chip *chip;
unsigned long flags;
int err = -EINVAL;
@@ -2196,19 +2665,7 @@
data = irq_desc_get_irq_data(desc);
- do {
- chip = irq_data_get_irq_chip(data);
- if (chip->irq_get_irqchip_state)
- break;
-#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
- data = data->parent_data;
-#else
- data = NULL;
-#endif
- } while (data);
-
- if (data)
- err = chip->irq_get_irqchip_state(data, which, state);
+ err = __irq_get_irqchip_state(data, which, state);
irq_put_desc_busunlock(desc, flags);
return err;