ACPI: fix acpi_hest_firmware_first_pci() caused oops

acpi_hest_firmware_first_pci() could be called when acpi is disabled
and cause system oops.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/acpi/hest.c b/drivers/acpi/hest.c
index 4bb18c980ac6..1c527a192872 100644
--- a/drivers/acpi/hest.c
+++ b/drivers/acpi/hest.c
@@ -123,6 +123,10 @@ int acpi_hest_firmware_first_pci(struct pci_dev *pci)
 {
         acpi_status status = AE_NOT_FOUND;
         struct acpi_table_header *hest = NULL;
+
+        if (acpi_disabled)
+                return 0;
+
         status = acpi_get_table(ACPI_SIG_HEST, 1, &hest);
 
         if (ACPI_SUCCESS(status)) {