ACPI: sysfs: Make ACPI GPE mask kernel parameter cover all GPEs

The acpi_mask_gpe= kernel parameter documentation states that the range
of mask is 128 GPEs (0x00 to 0x7F).  The acpi_masked_gpes mask is a u64 so
only 64 GPEs (0x00 to 0x3F) can really be masked.

Use a bitmap of size 0xFF instead of a u64 for the GPE mask so 256
GPEs can be masked.

Fixes: 9c4aa1eecb48 (ACPI / sysfs: Provide quirk mechanism to prevent GPE flooding)
Signed-off-by: Prarit Bharava <prarit@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

2 files changed, 8 insertions, 19 deletions

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 6571fbfdb2a1..89ba74761180 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -114,7 +114,6 @@
                         This facility can be used to prevent such uncontrolled
                         GPE floodings.
                         Format: <int>
-                        Support masking of GPEs numbered from 0x00 to 0x7f.
 
         acpi_no_auto_serialize  [HW,ACPI]
                         Disable auto-serialization of AML methods
diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c
index 06a150bb35bf..4fc59c3bc673 100644
--- a/drivers/acpi/sysfs.c
+++ b/drivers/acpi/sysfs.c
@@ -816,14 +816,8 @@ end:
  * interface:
  *   echo unmask > /sys/firmware/acpi/interrupts/gpe00
  */
-
-/*
- * Currently, the GPE flooding prevention only supports to mask the GPEs
- * numbered from 00 to 7f.
- */
-#define ACPI_MASKABLE_GPE_MAX   0x80
-
-static u64 __initdata acpi_masked_gpes;
+#define ACPI_MASKABLE_GPE_MAX   0xFF
+static DECLARE_BITMAP(acpi_masked_gpes_map, ACPI_MASKABLE_GPE_MAX) __initdata;
 
 static int __init acpi_gpe_set_masked_gpes(char *val)
 {
@@ -831,7 +825,7 @@ static int __init acpi_gpe_set_masked_gpes(char *val)
 
         if (kstrtou8(val, 0, &gpe) || gpe > ACPI_MASKABLE_GPE_MAX)
                 return -EINVAL;
-        acpi_masked_gpes |= ((u64)1<<gpe);
+        set_bit(gpe, acpi_masked_gpes_map);
 
         return 1;
 }
@@ -843,15 +837,11 @@ void __init acpi_gpe_apply_masked_gpes(void)
         acpi_status status;
         u8 gpe;
 
-        for (gpe = 0;
-             gpe < min_t(u8, ACPI_MASKABLE_GPE_MAX, acpi_current_gpe_count);
-             gpe++) {
-                if (acpi_masked_gpes & ((u64)1<<gpe)) {
-                        status = acpi_get_gpe_device(gpe, &handle);
-                        if (ACPI_SUCCESS(status)) {
-                                pr_info("Masking GPE 0x%x.\n", gpe);
-                                (void)acpi_mask_gpe(handle, gpe, TRUE);
-                        }
+        for_each_set_bit(gpe, acpi_masked_gpes_map, ACPI_MASKABLE_GPE_MAX) {
+                status = acpi_get_gpe_device(gpe, &handle);
+                if (ACPI_SUCCESS(status)) {
+                        pr_info("Masking GPE 0x%x.\n", gpe);
+                        (void)acpi_mask_gpe(handle, gpe, TRUE);
                 }
         }
 }