ACPI: Fix bug when ACPI reset register is implemented in system memory
Use acpi_os_map_generic_address to pre-map the reset register if it is
memory mapped, thereby preventing the BUG_ON() in line 1319 of
mm/vmalloc.c from triggering during panic-triggered reboots.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=77131
Signed-off-by: Randy Wright <rwright@hp.com>
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
[rjw: Changelog, simplified code]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 6776c59..88cddf8 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -1798,6 +1798,16 @@
acpi_os_map_generic_address(&acpi_gbl_FADT.xpm1b_event_block);
acpi_os_map_generic_address(&acpi_gbl_FADT.xgpe0_block);
acpi_os_map_generic_address(&acpi_gbl_FADT.xgpe1_block);
+ if (acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER) {
+ /*
+ * Use acpi_os_map_generic_address to pre-map the reset
+ * register if it's in system memory.
+ */
+ int rv;
+
+ rv = acpi_os_map_generic_address(&acpi_gbl_FADT.reset_register);
+ pr_debug(PREFIX "%s: map reset_reg status %d\n", __func__, rv);
+ }
return AE_OK;
}
@@ -1826,6 +1836,8 @@
acpi_os_unmap_generic_address(&acpi_gbl_FADT.xgpe0_block);
acpi_os_unmap_generic_address(&acpi_gbl_FADT.xpm1b_event_block);
acpi_os_unmap_generic_address(&acpi_gbl_FADT.xpm1a_event_block);
+ if (acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER)
+ acpi_os_unmap_generic_address(&acpi_gbl_FADT.reset_register);
destroy_workqueue(kacpid_wq);
destroy_workqueue(kacpi_notify_wq);