4 files changed, 65 insertions, 16 deletions

diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c
index aa1f743152a2..8714f8c271ba 100644
--- a/drivers/firmware/efi/arm-init.c
+++ b/drivers/firmware/efi/arm-init.c
@@ -203,7 +203,19 @@ void __init efi_init(void)
 
 	reserve_regions();
 	early_memunmap(memmap.map, params.mmap_size);
-	memblock_mark_nomap(params.mmap & PAGE_MASK,
-			    PAGE_ALIGN(params.mmap_size +
-				       (params.mmap & ~PAGE_MASK)));
+
+	if (IS_ENABLED(CONFIG_ARM)) {
+		/*
+		 * ARM currently does not allow ioremap_cache() to be called on
+		 * memory regions that are covered by struct page. So remove the
+		 * UEFI memory map from the linear mapping.
+		 */
+		memblock_mark_nomap(params.mmap & PAGE_MASK,
+				    PAGE_ALIGN(params.mmap_size +
+					       (params.mmap & ~PAGE_MASK)));
+	} else {
+		memblock_reserve(params.mmap & PAGE_MASK,
+				 PAGE_ALIGN(params.mmap_size +
+					    (params.mmap & ~PAGE_MASK)));
+	}
 }
diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c
index 0ac594c0a234..34b741940494 100644
--- a/drivers/firmware/efi/vars.c
+++ b/drivers/firmware/efi/vars.c
@@ -202,29 +202,44 @@ static const struct variable_validate variable_validate[] = {
 	{ NULL_GUID, "", NULL },
 };
 
+/*
+ * Check if @var_name matches the pattern given in @match_name.
+ *
+ * @var_name: an array of @len non-NUL characters.
+ * @match_name: a NUL-terminated pattern string, optionally ending in "*". A
+ *              final "*" character matches any trailing characters @var_name,
+ *              including the case when there are none left in @var_name.
+ * @match: on output, the number of non-wildcard characters in @match_name
+ *         that @var_name matches, regardless of the return value.
+ * @return: whether @var_name fully matches @match_name.
+ */
 static bool
 variable_matches(const char *var_name, size_t len, const char *match_name,
 		 int *match)
 {
 	for (*match = 0; ; (*match)++) {
 		char c = match_name[*match];
-		char u = var_name[*match];
 
-		/* Wildcard in the matching name means we've matched */
-		if (c == '*')
+		switch (c) {
+		case '*':
+			/* Wildcard in @match_name means we've matched. */
 			return true;
 
-		/* Case sensitive match */
-		if (!c && *match == len)
-			return true;
+		case '\0':
+			/* @match_name has ended. Has @var_name too? */
+			return (*match == len);
 
-		if (c != u)
+		default:
+			/*
+			 * We've reached a non-wildcard char in @match_name.
+			 * Continue only if there's an identical character in
+			 * @var_name.
+			 */
+			if (*match < len && c == var_name[*match])
+				continue;
 			return false;
-
-		if (!c)
-			return true;
+		}
 	}
-	return true;
 }
 
 bool
diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c
index 11bfee8b79a9..b5d05807e6ec 100644
--- a/drivers/firmware/psci.c
+++ b/drivers/firmware/psci.c
@@ -360,7 +360,7 @@ static struct cpuidle_ops psci_cpuidle_ops __initdata = {
 	.init = psci_dt_cpu_init_idle,
 };
 
-CPUIDLE_METHOD_OF_DECLARE(psci, "arm,psci", &psci_cpuidle_ops);
+CPUIDLE_METHOD_OF_DECLARE(psci, "psci", &psci_cpuidle_ops);
 #endif
 #endif
 
diff --git a/drivers/firmware/qemu_fw_cfg.c b/drivers/firmware/qemu_fw_cfg.c
index fedbff55a7f3..1b95475b6aef 100644
--- a/drivers/firmware/qemu_fw_cfg.c
+++ b/drivers/firmware/qemu_fw_cfg.c
@@ -77,12 +77,28 @@ static inline u16 fw_cfg_sel_endianness(u16 key)
 static inline void fw_cfg_read_blob(u16 key,
 				    void *buf, loff_t pos, size_t count)
 {
+	u32 glk = -1U;
+	acpi_status status;
+
+	/* If we have ACPI, ensure mutual exclusion against any potential
+	 * device access by the firmware, e.g. via AML methods:
+	 */
+	status = acpi_acquire_global_lock(ACPI_WAIT_FOREVER, &glk);
+	if (ACPI_FAILURE(status) && status != AE_NOT_CONFIGURED) {
+		/* Should never get here */
+		WARN(1, "fw_cfg_read_blob: Failed to lock ACPI!\n");
+		memset(buf, 0, count);
+		return;
+	}
+
 	mutex_lock(&fw_cfg_dev_lock);
 	iowrite16(fw_cfg_sel_endianness(key), fw_cfg_reg_ctrl);
 	while (pos-- > 0)
 		ioread8(fw_cfg_reg_data);
 	ioread8_rep(fw_cfg_reg_data, buf, count);
 	mutex_unlock(&fw_cfg_dev_lock);
+
+	acpi_release_global_lock(glk);
 }
 
 /* clean up fw_cfg device i/o */
@@ -727,12 +743,18 @@ device_param_cb(mmio, &fw_cfg_cmdline_param_ops, NULL, S_IRUSR);
 
 static int __init fw_cfg_sysfs_init(void)
 {
+	int ret;
+
 	/* create /sys/firmware/qemu_fw_cfg/ top level directory */
 	fw_cfg_top_ko = kobject_create_and_add("qemu_fw_cfg", firmware_kobj);
 	if (!fw_cfg_top_ko)
 		return -ENOMEM;
 
-	return platform_driver_register(&fw_cfg_sysfs_driver);
+	ret = platform_driver_register(&fw_cfg_sysfs_driver);
+	if (ret)
+		fw_cfg_kobj_cleanup(fw_cfg_top_ko);
+
+	return ret;
 }
 
 static void __exit fw_cfg_sysfs_exit(void)