[PATCH 4.16 151/272] ACPICA: Events: add a return on failure from acpi_hw_register_read

Greg Kroah-Hartman
2018-05-28T11:11:47Z

From: Erik Schmauss <erik.schmauss@intel.com>

[ Upstream commit b4c0de312613ca676db5bd7e696a44b56795612a ]

This ensures that acpi_ev_fixed_event_detect() does not use fixed_status
and and fixed_enable as uninitialized variables.

Signed-off-by: Erik Schmauss <erik.schmauss@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/acpi/acpica/evevent.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

--- a/drivers/acpi/acpica/evevent.c
+++ b/drivers/acpi/acpica/evevent.c
@@ -204,6 +204,7 @@ u32 acpi_ev_fixed_event_detect(void)
u32 fixed_status;
u32 fixed_enable;
u32 i;
+ acpi_status status;

ACPI_FUNCTION_NAME(ev_fixed_event_detect);

@@ -211,8 +212,12 @@ u32 acpi_ev_fixed_event_detect(void)
* Read the fixed feature status and enable registers, as all the cases
* depend on their values. Ignore errors here.
*/
- (void)acpi_hw_register_read(ACPI_REGISTER_PM1_STATUS, &fixed_status);
- (void)acpi_hw_register_read(ACPI_REGISTER_PM1_ENABLE, &fixed_enable);
+ status = acpi_hw_register_read(ACPI_REGISTER_PM1_STATUS, &fixed_status);
+ status |=
+ acpi_hw_register_read(ACPI_REGISTER_PM1_ENABLE, &fixed_enable);
+ if (ACPI_FAILURE(status)) {
+ return (int_status);
+ }

ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
"Fixed Event Block: Enable %08X Status %08X\n",