lkml.org 
[lkml]   [2015]   [Feb]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/2] cpuidle / sleep: Do sanity checks in cpuidle_enter_freeze() too
Date
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Modify cpuidle_enter_freeze() to do the sanity checks done by
cpuidle_select() to avoid crashing the suspend-to-idle code
path in case something is missing.

Original-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/cpuidle/cpuidle.c | 23 ++++++++++++++++-------
1 file changed, 16 insertions(+), 7 deletions(-)

Index: linux-pm/drivers/cpuidle/cpuidle.c
===================================================================
--- linux-pm.orig/drivers/cpuidle/cpuidle.c
+++ linux-pm/drivers/cpuidle/cpuidle.c
@@ -44,6 +44,12 @@ void disable_cpuidle(void)
off = 1;
}

+static bool cpuidle_not_available(struct cpuidle_driver *drv,
+ struct cpuidle_device *dev)
+{
+ return off || !initialized || !drv || !dev || !dev->enabled;
+}
+
/**
* cpuidle_play_dead - cpu off-lining
*
@@ -126,6 +132,9 @@ void cpuidle_enter_freeze(void)
struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);
int index;

+ if (cpuidle_not_available(drv, dev))
+ goto fallback;
+
/*
* Find the deepest state with ->enter_freeze present, which guarantees
* that interrupts won't be enabled when it exits and allows the tick to
@@ -143,10 +152,13 @@ void cpuidle_enter_freeze(void)
* at all and try to enter it normally.
*/
index = cpuidle_find_deepest_state(drv, dev, false);
- if (index >= 0)
+ if (index >= 0) {
cpuidle_enter(drv, dev, index);
- else
- arch_cpu_idle();
+ return;
+ }
+
+ fallback:
+ arch_cpu_idle();
}

/**
@@ -205,12 +217,9 @@ int cpuidle_enter_state(struct cpuidle_d
*/
int cpuidle_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
{
- if (off || !initialized)
+ if (cpuidle_not_available(drv, dev))
return -ENODEV;

- if (!drv || !dev || !dev->enabled)
- return -EBUSY;
-
return cpuidle_curr_governor->select(drv, dev);
}



\
 
 \ /
  Last update: 2015-02-27 00:41    [W:0.184 / U:0.036 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site