+ acpi_evaluate_integer-avoid-using-kmalloc.patch added to -mm tree

[akpm@linux-foundation.org]

The patch titled
     acpi_evaluate_integer: avoid using kmalloc()
has been added to the -mm tree.  Its filename is
     acpi_evaluate_integer-avoid-using-kmalloc.patch

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------------------------------------------------------
Subject: acpi_evaluate_integer: avoid using kmalloc()
From: Pavel Machek <pavel@suse.cz>

Now I know why I had strange "scheduling in atomic" problems:
acpi_evaluate_integer() does malloc(..., irqs_disabled() ? GFP_ATOMIC
: GFP_KERNEL)... which is (of course) broken.

There's no way to reliably tell if we need GFP_ATOMIC or not from code,
this one for example fails to detect spinlocks held.

Fortunately, allocation seems small enough to be done on stack.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: "Moore, Robert" <robert.moore@intel.com>
Cc: "Brown, Len" <len.brown@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/acpi/utils.c |   16 ++++------------
 1 file changed, 4 insertions(+), 12 deletions(-)

diff -puN drivers/acpi/utils.c~acpi_evaluate_integer-avoid-using-kmalloc drivers/acpi/utils.c
--- a/drivers/acpi/utils.c~acpi_evaluate_integer-avoid-using-kmalloc
+++ a/drivers/acpi/utils.c
@@ -259,34 +259,26 @@ acpi_evaluate_integer(acpi_handle handle
 		      struct acpi_object_list *arguments, unsigned long long *data)
 {
 	acpi_status status = AE_OK;
-	union acpi_object *element;
+	union acpi_object element;
 	struct acpi_buffer buffer = { 0, NULL };
 
-
 	if (!data)
 		return AE_BAD_PARAMETER;
 
-	element = kzalloc(sizeof(union acpi_object), irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL);
-	if (!element)
-		return AE_NO_MEMORY;
-
 	buffer.length = sizeof(union acpi_object);
-	buffer.pointer = element;
+	buffer.pointer = &element;
 	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
 	if (ACPI_FAILURE(status)) {
 		acpi_util_eval_error(handle, pathname, status);
-		kfree(element);
 		return status;
 	}
 
-	if (element->type != ACPI_TYPE_INTEGER) {
+	if (element.type != ACPI_TYPE_INTEGER) {
 		acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
-		kfree(element);
 		return AE_BAD_DATA;
 	}
 
-	*data = element->integer.value;
-	kfree(element);
+	*data = element.integer.value;
 
 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
 
_

Patches currently in -mm which might be from pavel@suse.cz are

linux-next.patch
backlight-catch-invalid-input.patch
backlight-catch-invalid-input-checkpatch-fixes.patch
acpi_evaluate_integer-avoid-using-kmalloc.patch
strict_strto-is-not-strict-enough.patch
lis3lv02d-separate-the-core-from-hp-acpi-api.patch
lis3lv02d-merge-with-leds-hp-disk.patch