Merge branch 'x86-alternatives-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-alternatives-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, alternatives: BUG on encountering an invalid CPU feature number
  x86, alternatives: Fix one more open-coded 8-bit alternative number
  x86, alternatives: Use 16-bit numbers for cpufeature index

2 files changed, 12 insertions, 9 deletions

diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h
index 03b6bb5394a0..bc6abb7bc7ee 100644
--- a/arch/x86/include/asm/alternative.h
+++ b/arch/x86/include/asm/alternative.h
@@ -45,10 +45,9 @@
 struct alt_instr {
         u8 *instr;              /* original instruction */
         u8 *replacement;
-        u8  cpuid;              /* cpuid bit set for replacement */
+        u16 cpuid;              /* cpuid bit set for replacement */
         u8  instrlen;           /* length of original instruction */
         u8  replacementlen;     /* length of new instruction, <= instrlen */
-        u8  pad1;
 #ifdef CONFIG_X86_64
         u32 pad2;
 #endif
@@ -86,9 +85,11 @@ static inline int alternatives_text_reserved(void *start, void *end)
       _ASM_ALIGN "\n"                                                   \
       _ASM_PTR "661b\n"                         /* label           */   \
       _ASM_PTR "663f\n"                         /* new instruction */   \
-      "  .byte " __stringify(feature) "\n"      /* feature bit     */   \
+      "  .word " __stringify(feature) "\n"      /* feature bit     */   \
       "  .byte 662b-661b\n"                     /* sourcelen       */   \
       "  .byte 664f-663f\n"                     /* replacementlen  */   \
+      ".previous\n"                                                     \
+      ".section .discard,\"aw\",@progbits\n"                            \
       "  .byte 0xff + (664f-663f) - (662b-661b)\n" /* rlen <= slen */   \
       ".previous\n"                                                     \
       ".section .altinstr_replacement, \"ax\"\n"                        \
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index 0b205b8a4308..781a50b29a49 100644
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -302,7 +302,7 @@ extern const char * const x86_power_flags[32];
  * patch the target code for additional performance.
  *
  */
-static __always_inline __pure bool __static_cpu_has(u8 bit)
+static __always_inline __pure bool __static_cpu_has(u16 bit)
 {
 #if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
                 asm goto("1: jmp %l[t_no]\n"
@@ -311,11 +311,11 @@ static __always_inline __pure bool __static_cpu_has(u8 bit)
                          _ASM_ALIGN "\n"
                          _ASM_PTR "1b\n"
                          _ASM_PTR "0\n"         /* no replacement */
-                         " .byte %P0\n"         /* feature bit */
+                         " .word %P0\n"         /* feature bit */
                          " .byte 2b - 1b\n"     /* source len */
                          " .byte 0\n"           /* replacement len */
-                         " .byte 0xff + 0 - (2b-1b)\n"  /* padding */
                          ".previous\n"
+                         /* skipping size check since replacement size = 0 */
                          : : "i" (bit) : : t_no);
                 return true;
         t_no:
@@ -329,10 +329,12 @@ static __always_inline __pure bool __static_cpu_has(u8 bit)
                              _ASM_ALIGN "\n"
                              _ASM_PTR "1b\n"
                              _ASM_PTR "3f\n"
-                             " .byte %P1\n"             /* feature bit */
+                             " .word %P1\n"             /* feature bit */
                              " .byte 2b - 1b\n"         /* source len */
                              " .byte 4f - 3f\n"         /* replacement len */
-                             " .byte 0xff + (4f-3f) - (2b-1b)\n" /* padding */
+                             ".previous\n"
+                             ".section .discard,\"aw\",@progbits\n"
+                             " .byte 0xff + (4f-3f) - (2b-1b)\n" /* size check */
                              ".previous\n"
                              ".section .altinstr_replacement,\"ax\"\n"
                              "3: movb $1,%0\n"
@@ -348,7 +350,7 @@ static __always_inline __pure bool __static_cpu_has(u8 bit)
 (                                                               \
         __builtin_constant_p(boot_cpu_has(bit)) ?               \
                 boot_cpu_has(bit) :                             \
-        (__builtin_constant_p(bit) && !((bit) & ~0xff)) ?       \
+        __builtin_constant_p(bit) ?                             \
                 __static_cpu_has(bit) :                         \
                 boot_cpu_has(bit)                               \
 )