diff options
| author | Toshi Kani <toshi.kani@hp.com> | 2012-03-31 21:37:02 -0600 |
|---|---|---|
| committer | Len Brown <len.brown@intel.com> | 2012-04-06 15:01:25 -0400 |
| commit | ee01e663373343c63e0e3d364d09f6155378dbcc (patch) | |
| tree | 22448567769278f9af4f8bff9bfc7653be94885c /drivers | |
| parent | 54f70077768e9aba37d9c5030b43497b6d5084fb (diff) | |
| download | linux-stable-ee01e663373343c63e0e3d364d09f6155378dbcc.tar.gz linux-stable-ee01e663373343c63e0e3d364d09f6155378dbcc.tar.bz2 linux-stable-ee01e663373343c63e0e3d364d09f6155378dbcc.zip | |
cpuidle: Fix panic in CPU off-lining with no idle driver
Fix a NULL pointer dereference panic in cpuidle_play_dead() during
CPU off-lining when no cpuidle driver is registered. A cpuidle
driver may be registered at boot-time based on CPU type. This patch
allows an off-lined CPU to enter HLT-based idle in this condition.
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: Boris Ostrovsky <boris.ostrovsky@amd.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Tested-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/cpuidle/cpuidle.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 3e146b2ada4a..a71376a45d8e 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -74,7 +74,7 @@ static cpuidle_enter_t cpuidle_enter_ops; /** * cpuidle_play_dead - cpu off-lining * - * Only returns in case of an error + * Returns in case of an error or no driver */ int cpuidle_play_dead(void) { @@ -83,6 +83,9 @@ int cpuidle_play_dead(void) int i, dead_state = -1; int power_usage = -1; + if (!drv) + return -ENODEV; + /* Find lowest-power state that supports long-term idle */ for (i = CPUIDLE_DRIVER_STATE_START; i < drv->state_count; i++) { struct cpuidle_state *s = &drv->states[i]; |