ACPI: sanity check _PSS frequency to prevent cpufreq crash

[karo-tx-linux.git] / drivers / acpi / processor_perflib.c

diff --git a/drivers/acpi/processor_perflib.c b/drivers/acpi/processor_perflib.c
index cafb41000f6bd6b36eaaa4b4348faef59e5c0e49..60e543d3234ea8528b2e55537511690ee3be0d96 100644 (file)
--- a/drivers/acpi/processor_perflib.c
+++ b/drivers/acpi/processor_perflib.c
@@ -309,9 +309,15 @@ static int acpi_processor_get_performance_states(struct acpi_processor *pr)
                                  (u32) px->bus_master_latency,
                                  (u32) px->control, (u32) px->status));
 
-               if (!px->core_frequency) {
-                       printk(KERN_ERR PREFIX
-                                   "Invalid _PSS data: freq is zero\n");
+               /*
+                * Check that ACPI's u64 MHz will be valid as u32 KHz in cpufreq
+                */
+               if (!px->core_frequency ||
+                   ((u32)(px->core_frequency * 1000) !=
+                    (px->core_frequency * 1000))) {
+                       printk(KERN_ERR FW_BUG PREFIX
+                              "Invalid BIOS _PSS frequency: 0x%llx MHz\n",
+                              px->core_frequency);
                        result = -EFAULT;
                        kfree(pr->performance->states);
                        goto end;