2 files changed, 29 insertions, 37 deletions

diff --git a/drivers/firmware/dmi-sysfs.c b/drivers/firmware/dmi-sysfs.c
index d5de6ee8466d..ecf2eeb5f6f9 100644
--- a/drivers/firmware/dmi-sysfs.c
+++ b/drivers/firmware/dmi-sysfs.c
@@ -652,7 +652,7 @@ static int __init dmi_sysfs_init(void)
         int val;
 
         if (!dmi_kobj) {
-                pr_err("dmi-sysfs: dmi entry is absent.\n");
+                pr_debug("dmi-sysfs: dmi entry is absent.\n");
                 error = -ENODATA;
                 goto err;
         }
diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c
index 783041964439..e763e1484331 100644
--- a/drivers/firmware/dmi_scan.c
+++ b/drivers/firmware/dmi_scan.c
@@ -18,7 +18,7 @@ EXPORT_SYMBOL_GPL(dmi_kobj);
  * of and an antecedent to, SMBIOS, which stands for System
  * Management BIOS.  See further: http://www.dmtf.org/standards
  */
-static const char dmi_empty_string[] = "        ";
+static const char dmi_empty_string[] = "";
 
 static u32 dmi_ver __initdata;
 static u32 dmi_len;
@@ -26,11 +26,6 @@ static u16 dmi_num;
 static u8 smbios_entry_point[32];
 static int smbios_entry_point_size;
 
-/*
- * Catch too early calls to dmi_check_system():
- */
-static int dmi_initialized;
-
 /* DMI system identification string used during boot */
 static char dmi_ids_string[128] __initdata;
 
@@ -44,25 +39,21 @@ static int dmi_memdev_nr;
 static const char * __init dmi_string_nosave(const struct dmi_header *dm, u8 s)
 {
         const u8 *bp = ((u8 *) dm) + dm->length;
+        const u8 *nsp;
 
         if (s) {
-                s--;
-                while (s > 0 && *bp) {
+                while (--s > 0 && *bp)
                         bp += strlen(bp) + 1;
-                        s--;
-                }
 
-                if (*bp != 0) {
-                        size_t len = strlen(bp)+1;
-                        size_t cmp_len = len > 8 ? 8 : len;
-
-                        if (!memcmp(bp, dmi_empty_string, cmp_len))
-                                return dmi_empty_string;
+                /* Strings containing only spaces are considered empty */
+                nsp = bp;
+                while (*nsp == ' ')
+                        nsp++;
+                if (*nsp != '\0')
                         return bp;
-                }
         }
 
-        return "";
+        return dmi_empty_string;
 }
 
 static const char * __init dmi_string(const struct dmi_header *dm, u8 s)
@@ -633,7 +624,7 @@ void __init dmi_scan_machine(void)
 
                         if (!dmi_smbios3_present(buf)) {
                                 dmi_available = 1;
-                                goto out;
+                                return;
                         }
                 }
                 if (efi.smbios == EFI_INVALID_TABLE_ADDR)
@@ -651,7 +642,7 @@ void __init dmi_scan_machine(void)
 
                 if (!dmi_present(buf)) {
                         dmi_available = 1;
-                        goto out;
+                        return;
                 }
         } else if (IS_ENABLED(CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK)) {
                 p = dmi_early_remap(0xF0000, 0x10000);
@@ -668,7 +659,7 @@ void __init dmi_scan_machine(void)
                         if (!dmi_smbios3_present(buf)) {
                                 dmi_available = 1;
                                 dmi_early_unmap(p, 0x10000);
-                                goto out;
+                                return;
                         }
                         memcpy(buf, buf + 16, 16);
                 }
@@ -686,7 +677,7 @@ void __init dmi_scan_machine(void)
                         if (!dmi_present(buf)) {
                                 dmi_available = 1;
                                 dmi_early_unmap(p, 0x10000);
-                                goto out;
+                                return;
                         }
                         memcpy(buf, buf + 16, 16);
                 }
@@ -694,8 +685,6 @@ void __init dmi_scan_machine(void)
         }
  error:
         pr_info("DMI not present or invalid.\n");
- out:
-        dmi_initialized = 1;
 }
 
 static ssize_t raw_table_read(struct file *file, struct kobject *kobj,
@@ -715,10 +704,8 @@ static int __init dmi_init(void)
         u8 *dmi_table;
         int ret = -ENOMEM;
 
-        if (!dmi_available) {
-                ret = -ENODATA;
-                goto err;
-        }
+        if (!dmi_available)
+                return 0;
 
         /*
          * Set up dmi directory at /sys/firmware/dmi. This entry should stay
@@ -784,19 +771,20 @@ static bool dmi_matches(const struct dmi_system_id *dmi)
 {
         int i;
 
-        WARN(!dmi_initialized, KERN_ERR "dmi check: not initialized yet.\n");
-
         for (i = 0; i < ARRAY_SIZE(dmi->matches); i++) {
                 int s = dmi->matches[i].slot;
                 if (s == DMI_NONE)
                         break;
                 if (dmi_ident[s]) {
-                        if (!dmi->matches[i].exact_match &&
-                            strstr(dmi_ident[s], dmi->matches[i].substr))
-                                continue;
-                        else if (dmi->matches[i].exact_match &&
-                                 !strcmp(dmi_ident[s], dmi->matches[i].substr))
-                                continue;
+                        if (dmi->matches[i].exact_match) {
+                                if (!strcmp(dmi_ident[s],
+                                            dmi->matches[i].substr))
+                                        continue;
+                        } else {
+                                if (strstr(dmi_ident[s],
+                                           dmi->matches[i].substr))
+                                        continue;
+                        }
                 }
 
                 /* No match */
@@ -826,6 +814,8 @@ static bool dmi_is_end_of_table(const struct dmi_system_id *dmi)
  *      Walk the blacklist table running matching functions until someone
  *      returns non zero or we hit the end. Callback function is called for
  *      each successful match. Returns the number of matches.
+ *
+ *      dmi_scan_machine must be called before this function is called.
  */
 int dmi_check_system(const struct dmi_system_id *list)
 {
@@ -854,6 +844,8 @@ EXPORT_SYMBOL(dmi_check_system);
  *
  *      Walk the blacklist table until the first match is found.  Return the
  *      pointer to the matching entry or NULL if there's no match.
+ *
+ *      dmi_scan_machine must be called before this function is called.
  */
 const struct dmi_system_id *dmi_first_match(const struct dmi_system_id *list)
 {