ACPI: Fix boot problem related to APEI with acpi_disabled set

Commit 415e12b23792 ("PCI/ACPI: Request _OSC control once for each root
bridge (v3)") put the acpi_hest_init() call in acpi_pci_root_init() into
a wrong place, presumably because the author confused acpi_pci_disabled
with acpi_disabled.  Bring the code ordering in acpi_pci_root_init()
back to sanity.

Additionally, make sure that hest_disable is set when acpi_disabled is
set, which is going to prevent acpi_hest_parse(), that still may be
executed for acpi_disabled=1 through aer_acpi_firmware_first(), from
crashing because of uninitialized hest_tab.

Reported-and-tested-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/drivers/acpi/apei/hest.c b/drivers/acpi/apei/hest.c
index 4ee58e72b73..abda3786a5d 100644
--- a/drivers/acpi/apei/hest.c
+++ b/drivers/acpi/apei/hest.c
@@ -201,14 +201,14 @@ void __init acpi_hest_init(void)
         int rc = -ENODEV;
         unsigned int ghes_count = 0;
 
-        if (acpi_disabled)
-                return;
-
         if (hest_disable) {
                 pr_info(HEST_PFX "Table parsing disabled.\n");
                 return;
         }
 
+        if (acpi_disabled)
+                goto err;
+
         status = acpi_get_table(ACPI_SIG_HEST, 0,
                                 (struct acpi_table_header **)&hest_tab);
         if (status == AE_NOT_FOUND) {