ACPI: pdc init related memory leak with physical CPU hotplug

arch_acpi_processor_cleanup_pdc() in x86 and ia64 results in memory allocated
for _PDC objects that is never freed and will cause memory leak in case of
physical CPU remove and add. Patch fixes the memory leak by freeing the
objects soon after _PDC is evaluated.

Reported-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

4 files changed, 28 insertions, 0 deletions

diff --git a/arch/ia64/kernel/acpi-processor.c b/arch/ia64/kernel/acpi-processor.c
index cbe6cee5a550..dbda7bde6112 100644
--- a/arch/ia64/kernel/acpi-processor.c
+++ b/arch/ia64/kernel/acpi-processor.c
@@ -71,3 +71,15 @@ void arch_acpi_processor_init_pdc(struct acpi_processor *pr)
 }
 
 EXPORT_SYMBOL(arch_acpi_processor_init_pdc);
+
+void arch_acpi_processor_cleanup_pdc(struct acpi_processor *pr)
+{
+        if (pr->pdc) {
+                kfree(pr->pdc->pointer->buffer.pointer);
+                kfree(pr->pdc->pointer);
+                kfree(pr->pdc);
+                pr->pdc = NULL;
+        }
+}
+
+EXPORT_SYMBOL(arch_acpi_processor_cleanup_pdc);
diff --git a/arch/x86/kernel/acpi/processor.c b/arch/x86/kernel/acpi/processor.c
index 7c074eec39fb..d296f4a195c9 100644
--- a/arch/x86/kernel/acpi/processor.c
+++ b/arch/x86/kernel/acpi/processor.c
@@ -72,6 +72,7 @@ static void init_intel_pdc(struct acpi_processor *pr, struct cpuinfo_x86 *c)
         return;
 }
 
+
 /* Initialize _PDC data based on the CPU vendor */
 void arch_acpi_processor_init_pdc(struct acpi_processor *pr)
 {
@@ -85,3 +86,15 @@ void arch_acpi_processor_init_pdc(struct acpi_processor *pr)
 }
 
 EXPORT_SYMBOL(arch_acpi_processor_init_pdc);
+
+void arch_acpi_processor_cleanup_pdc(struct acpi_processor *pr)
+{
+        if (pr->pdc) {
+                kfree(pr->pdc->pointer->buffer.pointer);
+                kfree(pr->pdc->pointer);
+                kfree(pr->pdc);
+                pr->pdc = NULL;
+        }
+}
+
+EXPORT_SYMBOL(arch_acpi_processor_cleanup_pdc);
diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index 23f0fb84f1c1..d40d45e904a5 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -731,6 +731,8 @@ static int __cpuinit acpi_processor_start(struct acpi_device *device)
         /* _PDC call should be done before doing anything else (if reqd.). */
         arch_acpi_processor_init_pdc(pr);
         acpi_processor_set_pdc(pr);
+        arch_acpi_processor_cleanup_pdc(pr);
+
 #ifdef CONFIG_CPU_FREQ
         acpi_processor_ppc_has_changed(pr);
 #endif
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index 4927c063347c..baf1e0a9a7ee 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -258,6 +258,7 @@ DECLARE_PER_CPU(struct acpi_processor *, processors);
 extern struct acpi_processor_errata errata;
 
 void arch_acpi_processor_init_pdc(struct acpi_processor *pr);
+void arch_acpi_processor_cleanup_pdc(struct acpi_processor *pr);
 
 #ifdef ARCH_HAS_POWER_INIT
 void acpi_processor_power_init_bm_check(struct acpi_processor_flags *flags,