PM: Warn if interrupts are enabled during suspend-resume of sysdevs

Sysdevs have to be suspended and resumed with interrupts disabled and
things usually break in a way that's difficult to debug if one of
sysdev drivers enables interrupts by mistake during suspend or
resume.  Add extra checks that will generate warnings in such cases.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/base/sys.c b/drivers/base/sys.c
index 3236b434b964..9742a78c9fe4 100644
--- a/drivers/base/sys.c
+++ b/drivers/base/sys.c
@@ -343,11 +343,15 @@ static void __sysdev_resume(struct sys_device *dev)
         /* First, call the class-specific one */
         if (cls->resume)
                 cls->resume(dev);
+        WARN_ONCE(!irqs_disabled(),
+                "Interrupts enabled after %pF\n", cls->resume);
 
         /* Call auxillary drivers next. */
         list_for_each_entry(drv, &cls->drivers, entry) {
                 if (drv->resume)
                         drv->resume(dev);
+                WARN_ONCE(!irqs_disabled(),
+                        "Interrupts enabled after %pF\n", drv->resume);
         }
 }
 
@@ -377,6 +381,9 @@ int sysdev_suspend(pm_message_t state)
         if (ret)
                 return ret;
 
+        WARN_ONCE(!irqs_disabled(),
+                "Interrupts enabled while suspending system devices\n");
+
         pr_debug("Suspending System Devices\n");
 
         list_for_each_entry_reverse(cls, &system_kset->list, kset.kobj.entry) {
@@ -393,6 +400,9 @@ int sysdev_suspend(pm_message_t state)
                                         if (ret)
                                                 goto aux_driver;
                                 }
+                                WARN_ONCE(!irqs_disabled(),
+                                        "Interrupts enabled after %pF\n",
+                                        drv->suspend);
                         }
 
                         /* Now call the generic one */
@@ -400,6 +410,9 @@ int sysdev_suspend(pm_message_t state)
                                 ret = cls->suspend(sysdev, state);
                                 if (ret)
                                         goto cls_driver;
+                                WARN_ONCE(!irqs_disabled(),
+                                        "Interrupts enabled after %pF\n",
+                                        cls->suspend);
                         }
                 }
         }
@@ -452,6 +465,9 @@ int sysdev_resume(void)
 {
         struct sysdev_class *cls;
 
+        WARN_ONCE(!irqs_disabled(),
+                "Interrupts enabled while resuming system devices\n");
+
         pr_debug("Resuming System Devices\n");
 
         list_for_each_entry(cls, &system_kset->list, kset.kobj.entry) {