Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...

Pull x86 boot updates from Ingo Molnar:
 "Early command line options parsing enhancements from Dave Hansen, plus
  minor cleanups and enhancements"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Remove unused 'is_big_kernel' variable
  x86/boot: Use proper array element type in memset() size calculation
  x86/boot: Pass in size to early cmdline parsing
  x86/boot: Simplify early command line parsing
  x86/boot: Fix early command-line parsing when partial word matches
  x86/boot: Fix early command-line parsing when matching at end
  x86/boot: Simplify kernel load address alignment check
  x86/boot: Micro-optimize reset_early_page_tables()

diff --git a/arch/x86/boot/tools/build.c b/arch/x86/boot/tools/build.c
index a7661c430cd98d28795ddee61bf5506c5ef3a1e5..0702d2531bc7f441364adca7ebc2d0e1a227f0bd 100644 (file)
--- a/arch/x86/boot/tools/build.c
+++ b/arch/x86/boot/tools/build.c
@@ -49,7 +49,6 @@ typedef unsigned int   u32;
 
 /* This must be large enough to hold the entire setup */
 u8 buf[SETUP_SECT_MAX*512];
-int is_big_kernel;
 
 #define PECOFF_RELOC_RESERVE 0x20
 

diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 2c0f3407bd1f1ae8adcf43cacdb479c91c096669..1f4422d5c8d013992d6b97a6a08734bde5bdb2b1 100644 (file)
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -40,13 +40,8 @@ pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX);
 /* Wipe all early page tables except for the kernel symbol map */
 static void __init reset_early_page_tables(void)
 {
-       unsigned long i;
-
-       for (i = 0; i < PTRS_PER_PGD-1; i++)
-               early_level4_pgt[i].pgd = 0;
-
+       memset(early_level4_pgt, 0, sizeof(pgd_t)*(PTRS_PER_PGD-1));
        next_early_pgt = 0;
-
        write_cr3(__pa_nodebug(early_level4_pgt));
 }
 
@@ -54,7 +49,6 @@ static void __init reset_early_page_tables(void)
 int __init early_make_pgtable(unsigned long address)
 {
        unsigned long physaddr = address - __PAGE_OFFSET;
-       unsigned long i;
        pgdval_t pgd, *pgd_p;
        pudval_t pud, *pud_p;
        pmdval_t pmd, *pmd_p;
@@ -81,8 +75,7 @@ again:
                }
 
                pud_p = (pudval_t *)early_dynamic_pgts[next_early_pgt++];
-               for (i = 0; i < PTRS_PER_PUD; i++)
-                       pud_p[i] = 0;
+               memset(pud_p, 0, sizeof(*pud_p) * PTRS_PER_PUD);
                *pgd_p = (pgdval_t)pud_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
        }
        pud_p += pud_index(address);
@@ -97,8 +90,7 @@ again:
                }
 
                pmd_p = (pmdval_t *)early_dynamic_pgts[next_early_pgt++];
-               for (i = 0; i < PTRS_PER_PMD; i++)
-                       pmd_p[i] = 0;
+               memset(pmd_p, 0, sizeof(*pmd_p) * PTRS_PER_PMD);
                *pud_p = (pudval_t)pmd_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
        }
        pmd = (physaddr & PMD_MASK) + early_pmd_flags;

diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 2e974680f5ad4acb514f50bc69833a5e0ecb6268..22fbf9df61bb4eecbb5ffe530562b56c1def90b8 100644 (file)
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -75,9 +75,7 @@ startup_64:
        subq    $_text - __START_KERNEL_map, %rbp
 
        /* Is the address not 2M aligned? */
-       movq    %rbp, %rax
-       andl    $~PMD_PAGE_MASK, %eax
-       testl   %eax, %eax
+       testl   $~PMD_PAGE_MASK, %ebp
        jnz     bad_address
 
        /*

diff --git a/arch/x86/lib/cmdline.c b/arch/x86/lib/cmdline.c
index 422db000d72767adf718dc75db682e5df576e877..5cc78bf572325fb1c5b5d6f854bfe878c55dfeb3 100644 (file)
--- a/arch/x86/lib/cmdline.c
+++ b/arch/x86/lib/cmdline.c
@@ -21,12 +21,16 @@ static inline int myisspace(u8 c)
  * @option: option string to look for
  *
  * Returns the position of that @option (starts counting with 1)
- * or 0 on not found.
+ * or 0 on not found.  @option will only be found if it is found
+ * as an entire word in @cmdline.  For instance, if @option="car"
+ * then a cmdline which contains "cart" will not match.
  */
-int cmdline_find_option_bool(const char *cmdline, const char *option)
+static int
+__cmdline_find_option_bool(const char *cmdline, int max_cmdline_size,
+                          const char *option)
 {
        char c;
-       int len, pos = 0, wstart = 0;
+       int pos = 0, wstart = 0;
        const char *opptr = NULL;
        enum {
                st_wordstart = 0,       /* Start of word/after whitespace */
@@ -37,11 +41,11 @@ int cmdline_find_option_bool(const char *cmdline, const char *option)
        if (!cmdline)
                return -1;      /* No command line */
 
-       len = min_t(int, strlen(cmdline), COMMAND_LINE_SIZE);
-       if (!len)
-               return 0;
-
-       while (len--) {
+       /*
+        * This 'pos' check ensures we do not overrun
+        * a non-NULL-terminated 'cmdline'
+        */
+       while (pos < max_cmdline_size) {
                c = *(char *)cmdline++;
                pos++;
 
@@ -58,18 +62,35 @@ int cmdline_find_option_bool(const char *cmdline, const char *option)
                        /* fall through */
 
                case st_wordcmp:
-                       if (!*opptr)
+                       if (!*opptr) {
+                               /*
+                                * We matched all the way to the end of the
+                                * option we were looking for.  If the
+                                * command-line has a space _or_ ends, then
+                                * we matched!
+                                */
                                if (!c || myisspace(c))
                                        return wstart;
-                               else
-                                       state = st_wordskip;
-                       else if (!c)
+                               /*
+                                * We hit the end of the option, but _not_
+                                * the end of a word on the cmdline.  Not
+                                * a match.
+                                */
+                       } else if (!c) {
+                               /*
+                                * Hit the NULL terminator on the end of
+                                * cmdline.
+                                */
                                return 0;
-                       else if (c != *opptr++)
-                               state = st_wordskip;
-                       else if (!len)          /* last word and is matching */
-                               return wstart;
-                       break;
+                       } else if (c == *opptr++) {
+                               /*
+                                * We are currently matching, so continue
+                                * to the next character on the cmdline.
+                                */
+                               break;
+                       }
+                       state = st_wordskip;
+                       /* fall through */
 
                case st_wordskip:
                        if (!c)
@@ -82,3 +103,8 @@ int cmdline_find_option_bool(const char *cmdline, const char *option)
 
        return 0;       /* Buffer overrun */
 }
+
+int cmdline_find_option_bool(const char *cmdline, const char *option)
+{
+       return __cmdline_find_option_bool(cmdline, COMMAND_LINE_SIZE, option);
+}