Merge tag 'acpi-5.5-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull additional ACPI updates from Rafael Wysocki:
 "These close a nasty race condition in the ACPI memory mappings
  management code and an invalid parameter check in a library routing,
  allow GPE 0xFF to be masked via kernel command line, add a new lid
  switch blacklist entry and clean up Kconfig.

  Specifics:

   - Fix locking issue in acpi_os_map_cleanup() leading to a race
     condition that can be harnessed for provoking a kernel panic from
     user space (Francesco Ruggeri)

   - Fix parameter check in acpi_bus_get_private_data() (Vamshi K
     Sthambamkadi)

   - Allow GPE 0xFF to be masked via kernel command line (Yunfeng Ye)

   - Add a new lid switch blacklist entry for Acer Switch 10 SW5-032 to
     the ACPI button driver (Hans de Goede)

   - Clean up Kconfig (Krzysztof Kozlowski)"

* tag 'acpi-5.5-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: bus: Fix NULL pointer check in acpi_bus_get_private_data()
  ACPI: Fix Kconfig indentation
  ACPI: OSL: only free map once in osl.c
  ACPI: button: Add DMI quirk for Acer Switch 10 SW5-032 lid-switch
  ACPI: sysfs: Change ACPI_MASKABLE_GPE_MAX to 0x100

Documentation/admin-guide/kernel-parameters.txt

@@ -113,7 +113,7 @@
 			the GPE dispatcher.
 			This facility can be used to prevent such uncontrolled
 			GPE floodings.
-			Format: <int>
+			Format: <byte>
 
 	acpi_no_auto_serialize	[HW,ACPI]
 			Disable auto-serialization of AML methods

drivers/acpi/bus.c

@@ -153,7 +153,7 @@ int acpi_bus_get_private_data(acpi_handle handle, void **data)
 {
 	acpi_status status;
 
-	if (!*data)
+	if (!data)
 		return -EINVAL;
 
 	status = acpi_get_data(handle, acpi_bus_private_data_handler, data);

drivers/acpi/button.c

@@ -77,6 +77,19 @@ MODULE_DEVICE_TABLE(acpi, button_device_ids);
 
 /* Please keep this list sorted alphabetically by vendor and model */
 static const struct dmi_system_id dmi_lid_quirks[] = {
+	{
+		/*
+		 * Acer Switch 10 SW5-012. _LID method messes with home and
+		 * power button GPIO IRQ settings causing an interrupt storm on
+		 * both GPIOs. This is unfixable without a DSDT override, so we
+		 * have to disable the lid-switch functionality altogether :|
+		 */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Aspire SW5-012"),
+		},
+		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_DISABLED,
+	},
 	{
 		/*
 		 * Asus T200TA, _LID keeps reporting closed after every second

drivers/acpi/osl.c

@@ -374,19 +374,21 @@ void *__ref acpi_os_map_memory(acpi_physical_address phys, acpi_size size)
 }
 EXPORT_SYMBOL_GPL(acpi_os_map_memory);
 
-static void acpi_os_drop_map_ref(struct acpi_ioremap *map)
+/* Must be called with mutex_lock(&acpi_ioremap_lock) */
+static unsigned long acpi_os_drop_map_ref(struct acpi_ioremap *map)
 {
-	if (!--map->refcount)
+	unsigned long refcount = --map->refcount;
+
+	if (!refcount)
 		list_del_rcu(&map->list);
+	return refcount;
 }
 
 static void acpi_os_map_cleanup(struct acpi_ioremap *map)
 {
-	if (!map->refcount) {
 	synchronize_rcu_expedited();
 	acpi_unmap(map->phys, map->virt);
 	kfree(map);
-	}
 }
 
 /**
@@ -406,6 +408,7 @@ static void acpi_os_map_cleanup(struct acpi_ioremap *map)
 void __ref acpi_os_unmap_iomem(void __iomem *virt, acpi_size size)
 {
 	struct acpi_ioremap *map;
+	unsigned long refcount;
 
 	if (!acpi_permanent_mmap) {
 		__acpi_unmap_table(virt, size);
@@ -419,9 +422,10 @@ void __ref acpi_os_unmap_iomem(void __iomem *virt, acpi_size size)
 		WARN(true, PREFIX "%s: bad address %p\n", __func__, virt);
 		return;
 	}
-	acpi_os_drop_map_ref(map);
+	refcount = acpi_os_drop_map_ref(map);
 	mutex_unlock(&acpi_ioremap_lock);
 
+	if (!refcount)
 		acpi_os_map_cleanup(map);
 }
 EXPORT_SYMBOL_GPL(acpi_os_unmap_iomem);
@@ -457,6 +461,7 @@ void acpi_os_unmap_generic_address(struct acpi_generic_address *gas)
 {
 	u64 addr;
 	struct acpi_ioremap *map;
+	unsigned long refcount;
 
 	if (gas->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY)
 		return;
@@ -472,9 +477,10 @@ void acpi_os_unmap_generic_address(struct acpi_generic_address *gas)
 		mutex_unlock(&acpi_ioremap_lock);
 		return;
 	}
-	acpi_os_drop_map_ref(map);
+	refcount = acpi_os_drop_map_ref(map);
 	mutex_unlock(&acpi_ioremap_lock);
 
+	if (!refcount)
 		acpi_os_map_cleanup(map);
 }
 EXPORT_SYMBOL(acpi_os_unmap_generic_address);

drivers/acpi/sysfs.c

@@ -819,14 +819,14 @@ static ssize_t counter_set(struct kobject *kobj,
  * interface:
  *   echo unmask > /sys/firmware/acpi/interrupts/gpe00
  */
-#define ACPI_MASKABLE_GPE_MAX	0xFF
+#define ACPI_MASKABLE_GPE_MAX	0x100
 static DECLARE_BITMAP(acpi_masked_gpes_map, ACPI_MASKABLE_GPE_MAX) __initdata;
 
 static int __init acpi_gpe_set_masked_gpes(char *val)
 {
 	u8 gpe;
 
-	if (kstrtou8(val, 0, &gpe) || gpe > ACPI_MASKABLE_GPE_MAX)
+	if (kstrtou8(val, 0, &gpe))
 		return -EINVAL;
 	set_bit(gpe, acpi_masked_gpes_map);
 
@@ -838,7 +838,7 @@ void __init acpi_gpe_apply_masked_gpes(void)
 {
 	acpi_handle handle;
 	acpi_status status;
-	u8 gpe;
+	u16 gpe;
 
 	for_each_set_bit(gpe, acpi_masked_gpes_map, ACPI_MASKABLE_GPE_MAX) {
 		status = acpi_get_gpe_device(gpe, &handle);