@@ -, +, @@ 
    	* grub-core/loader/i386/multiboot_mbi.c: Handle space in command line.
    	* grub-core/loader/multiboot_mbi2.c: Likewise.
--- a/grub-core/Makefile.core.def	
+++ a/grub-core/Makefile.core.def	
@@ -1576,6 +1576,7 @@ module = {
   cppflags = "-DGRUB_USE_MULTIBOOT2";
 
   common = loader/multiboot.c;
+  common = lib/cmdline.c;
   common = loader/multiboot_mbi2.c;
   enable = x86;
   enable = mips;
@@ -1584,6 +1585,7 @@ module = {
 module = {
   name = multiboot;
   common = loader/multiboot.c;
+  common = lib/cmdline.c;
   x86 = loader/i386/multiboot_mbi.c;
   extra_dist = loader/multiboot_elfxx.c;
   enable = x86;
--- a/grub-core/loader/i386/multiboot_mbi.c	
+++ a/grub-core/loader/i386/multiboot_mbi.c	
@@ -35,6 +35,7 @@ 
 #include <grub/file.h>
 #include <grub/net.h>
 #include <grub/i18n.h>
+#include <grub/lib/cmdline.h>
 
 #ifdef GRUB_MACHINE_EFI
 #include <grub/efi/efi.h>
@@ -641,31 +642,18 @@ grub_err_t
 grub_multiboot_init_mbi (int argc, char *argv[])
 {
   grub_ssize_t len = 0;
-  char *p;
-  int i;
 
   grub_multiboot_free_mbi ();
 
-  for (i = 0; i < argc; i++)
-    len += grub_strlen (argv[i]) + 1;
-  if (len == 0)
-    len = 1;
+  len = grub_loader_cmdline_size (argc, argv);
 
-  cmdline = p = grub_malloc (len);
+  cmdline = grub_malloc (len);
   if (! cmdline)
     return grub_errno;
   cmdline_size = len;
 
-  for (i = 0; i < argc; i++)
-    {
-      p = grub_stpcpy (p, argv[i]);
-      *(p++) = ' ';
-    }
-
-  /* Remove the space after the last word.  */
-  if (p != cmdline)
-    p--;
-  *p = '\0';
+  grub_create_loader_cmdline (argc, argv, cmdline,
+			      cmdline_size);
 
   return GRUB_ERR_NONE;
 }
@@ -675,9 +663,7 @@ grub_multiboot_add_module (grub_addr_t start, grub_size_t size,
 			   int argc, char *argv[])
 {
   struct module *newmod;
-  char *p;
-  grub_ssize_t len = 0;
-  int i;
+  grub_size_t len = 0;
 
   newmod = grub_malloc (sizeof (*newmod));
   if (!newmod)
@@ -686,13 +672,9 @@ grub_multiboot_add_module (grub_addr_t start, grub_size_t size,
   newmod->size = size;
   newmod->next = 0;
 
-  for (i = 0; i < argc; i++)
-    len += grub_strlen (argv[i]) + 1;
-
-  if (len == 0)
-    len = 1;
+  len = grub_loader_cmdline_size (argc, argv);
 
-  newmod->cmdline = p = grub_malloc (len);
+  newmod->cmdline = grub_malloc (len);
   if (! newmod->cmdline)
     {
       grub_free (newmod);
@@ -701,24 +683,13 @@ grub_multiboot_add_module (grub_addr_t start, grub_size_t size,
   newmod->cmdline_size = len;
   total_modcmd += ALIGN_UP (len, 4);
 
-  for (i = 0; i < argc; i++)
-    {
-      p = grub_stpcpy (p, argv[i]);
-      *(p++) = ' ';
-    }
-
-  /* Remove the space after the last word.  */
-  if (p != newmod->cmdline)
-    p--;
-  *p = '\0';
+  grub_create_loader_cmdline (argc, argv, newmod->cmdline,
+			      newmod->cmdline_size);
 
   if (modules_last)
     modules_last->next = newmod;
   else
-    {
-      modules = newmod;
-      modules_last->next = NULL;
-    }
+    modules = newmod;
   modules_last = newmod;
 
   modcnt++;
--- a/grub-core/loader/multiboot_mbi2.c	
+++ a/grub-core/loader/multiboot_mbi2.c	
@@ -35,6 +35,8 @@ 
 #include <grub/video.h>
 #include <grub/acpi.h>
 #include <grub/i18n.h>
+#include <grub/net.h>
+#include <grub/lib/cmdline.h>
 
 #if defined (GRUB_MACHINE_EFI)
 #include <grub/efi/efi.h>
@@ -905,31 +906,18 @@ grub_err_t
 grub_multiboot_init_mbi (int argc, char *argv[])
 {
   grub_ssize_t len = 0;
-  char *p;
-  int i;
 
   grub_multiboot_free_mbi ();
 
-  for (i = 0; i < argc; i++)
-    len += grub_strlen (argv[i]) + 1;
-  if (len == 0)
-    len = 1;
+  len = grub_loader_cmdline_size (argc, argv);
 
-  cmdline = p = grub_malloc (len);
+  cmdline = grub_malloc (len);
   if (! cmdline)
     return grub_errno;
   cmdline_size = len;
 
-  for (i = 0; i < argc; i++)
-    {
-      p = grub_stpcpy (p, argv[i]);
-      *(p++) = ' ';
-    }
-
-  /* Remove the space after the last word.  */
-  if (p != cmdline)
-    p--;
-  *p = '\0';
+  grub_create_loader_cmdline (argc, argv, cmdline,
+			      cmdline_size);
 
   return GRUB_ERR_NONE;
 }
@@ -939,9 +927,7 @@ grub_multiboot_add_module (grub_addr_t start, grub_size_t size,
 			   int argc, char *argv[])
 {
   struct module *newmod;
-  char *p;
-  grub_ssize_t len = 0;
-  int i;
+  grub_size_t len = 0;
 
   newmod = grub_malloc (sizeof (*newmod));
   if (!newmod)
@@ -949,13 +935,9 @@ grub_multiboot_add_module (grub_addr_t start, grub_size_t size,
   newmod->start = start;
   newmod->size = size;
 
-  for (i = 0; i < argc; i++)
-    len += grub_strlen (argv[i]) + 1;
+  len = grub_loader_cmdline_size (argc, argv);
 
-  if (len == 0)
-    len = 1;
-
-  newmod->cmdline = p = grub_malloc (len);
+  newmod->cmdline = grub_malloc (len);
   if (! newmod->cmdline)
     {
       grub_free (newmod);
@@ -964,16 +946,8 @@ grub_multiboot_add_module (grub_addr_t start, grub_size_t size,
   newmod->cmdline_size = len;
   total_modcmd += ALIGN_UP (len, MULTIBOOT_TAG_ALIGN);
 
-  for (i = 0; i < argc; i++)
-    {
-      p = grub_stpcpy (p, argv[i]);
-      *(p++) = ' ';
-    }
-
-  /* Remove the space after the last word.  */
-  if (p != newmod->cmdline)
-    p--;
-  *p = '\0';
+  grub_create_loader_cmdline (argc, argv, newmod->cmdline,
+			      newmod->cmdline_size);
 
   if (modules_last)
     modules_last->next = newmod;