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

9 files changed, 19 insertions, 15 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)                               \
 )
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 70237732a6c7..f65ab8b014c4 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -214,6 +214,7 @@ void __init_or_module apply_alternatives(struct alt_instr *start,
                 u8 *instr = a->instr;
                 BUG_ON(a->replacementlen > a->instrlen);
                 BUG_ON(a->instrlen > sizeof(insnbuf));
+                BUG_ON(a->cpuid >= NCAPINTS*32);
                 if (!boot_cpu_has(a->cpuid))
                         continue;
 #ifdef CONFIG_X86_64
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index 258e93fa2630..227d00920d2f 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -913,7 +913,7 @@ ENTRY(simd_coprocessor_error)
         .balign 4
         .long 661b
         .long 663f
-        .byte X86_FEATURE_XMM
+        .word X86_FEATURE_XMM
         .byte 662b-661b
         .byte 664f-663f
 .previous
diff --git a/arch/x86/lib/clear_page_64.S b/arch/x86/lib/clear_page_64.S
index ebeafcce04a9..aa4326bfb24a 100644
--- a/arch/x86/lib/clear_page_64.S
+++ b/arch/x86/lib/clear_page_64.S
@@ -52,7 +52,7 @@ ENDPROC(clear_page)
         .align 8
         .quad clear_page
         .quad 1b
-        .byte X86_FEATURE_REP_GOOD
+        .word X86_FEATURE_REP_GOOD
         .byte .Lclear_page_end - clear_page
         .byte 2b - 1b
         .previous
diff --git a/arch/x86/lib/copy_page_64.S b/arch/x86/lib/copy_page_64.S
index 727a5d46d2fc..6fec2d1cebe1 100644
--- a/arch/x86/lib/copy_page_64.S
+++ b/arch/x86/lib/copy_page_64.S
@@ -113,7 +113,7 @@ ENDPROC(copy_page)
         .align 8
         .quad copy_page
         .quad 1b
-        .byte X86_FEATURE_REP_GOOD
+        .word X86_FEATURE_REP_GOOD
         .byte .Lcopy_page_end - copy_page
         .byte 2b - 1b
         .previous
diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S
index 71100c98e337..a460158b5ac5 100644
--- a/arch/x86/lib/copy_user_64.S
+++ b/arch/x86/lib/copy_user_64.S
@@ -29,7 +29,7 @@
         .align 8
         .quad  0b
         .quad  2b
-        .byte  \feature                 /* when feature is set */
+        .word  \feature                 /* when feature is set */
         .byte  5
         .byte  5
         .previous
diff --git a/arch/x86/lib/memcpy_64.S b/arch/x86/lib/memcpy_64.S
index f82e884928af..bcbcd1e0f7d5 100644
--- a/arch/x86/lib/memcpy_64.S
+++ b/arch/x86/lib/memcpy_64.S
@@ -131,7 +131,7 @@ ENDPROC(__memcpy)
         .align 8
         .quad memcpy
         .quad .Lmemcpy_c
-        .byte X86_FEATURE_REP_GOOD
+        .word X86_FEATURE_REP_GOOD
 
         /*
          * Replace only beginning, memcpy is used to apply alternatives,
diff --git a/arch/x86/lib/memset_64.S b/arch/x86/lib/memset_64.S
index e88d3b81644a..09d344269652 100644
--- a/arch/x86/lib/memset_64.S
+++ b/arch/x86/lib/memset_64.S
@@ -121,7 +121,7 @@ ENDPROC(__memset)
         .align 8
         .quad memset
         .quad .Lmemset_c
-        .byte X86_FEATURE_REP_GOOD
+        .word X86_FEATURE_REP_GOOD
         .byte .Lfinal - memset
         .byte .Lmemset_e - .Lmemset_c
         .previous