[PATCH 4.9 039/171] ACPI: sysfs: Make ACPI GPE mask kernel parameter cover all GPEs

Greg Kroah-Hartman
2018-11-08T21:50:09Z

[ Upstream commit 0f27cff8597d86f881ea8274b49b63b678c14a3c ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
Documentation/kernel-parameters.txt | 1 -
drivers/acpi/sysfs.c | 26 ++++++++------------------
2 files changed, 8 insertions(+), 19 deletions(-)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index f9f67be8d3c3..c708a50b060e 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -313,7 +313,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
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 cf05ae973381..a36d0739dbfe 100644
--- a/drivers/acpi/sysfs.c
+++ b/drivers/acpi/sysfs.c
@@ -724,14 +724,8 @@ 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)
{
@@ -739,7 +733,7 @@ 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;
}
@@ -751,15 +745,11 @@ 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);
}
}
}
--
2.17.1