[PATCH] x86_64: Proper null pointer check in powernow_k8_get
This prevents crashes on dual core system when enough ticks are lost.
Replaces earlier patch by me.
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/i386/kernel/cpu/cpufreq/powernow-k8.c b/arch/i386/kernel/cpu/cpufreq/powernow-k8.c
index 6ba497c..7c0e160 100644
--- a/arch/i386/kernel/cpu/cpufreq/powernow-k8.c
+++ b/arch/i386/kernel/cpu/cpufreq/powernow-k8.c
@@ -46,7 +46,7 @@
#define PFX "powernow-k8: "
#define BFX PFX "BIOS error: "
-#define VERSION "version 1.60.1"
+#define VERSION "version 1.60.2"
#include "powernow-k8.h"
/* serialize freq changes */
@@ -910,6 +910,9 @@
unsigned int newstate;
int ret = -EIO;
+ if (!data)
+ return -EINVAL;
+
/* only run on specific CPU from here on */
oldmask = current->cpus_allowed;
set_cpus_allowed(current, cpumask_of_cpu(pol->cpu));
@@ -969,6 +972,9 @@
{
struct powernow_k8_data *data = powernow_data[pol->cpu];
+ if (!data)
+ return -EINVAL;
+
return cpufreq_frequency_table_verify(pol, data->powernow_table);
}
@@ -1103,6 +1109,9 @@
if (!data)
return -EINVAL;
+ if (!data)
+ return -EINVAL;
+
set_cpus_allowed(current, cpumask_of_cpu(cpu));
if (smp_processor_id() != cpu) {
printk(KERN_ERR PFX "limiting to CPU %d failed in powernowk8_get\n", cpu);