Merge branch 'for-linus' of git://git.infradead.org/users/eparis/notify

[pandora-kernel.git] / arch / x86 / kernel / alternative.c

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index a36bb90..5079f24 100644 (file)
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -638,71 +638,32 @@ void *__kprobes text_poke_smp(void *addr, const void *opcode, size_t len)
        atomic_set(&stop_machine_first, 1);
        wrote_text = 0;
        /* Use __stop_machine() because the caller already got online_cpus. */
-       __stop_machine(stop_machine_text_poke, (void *)&tpp, NULL);
+       __stop_machine(stop_machine_text_poke, (void *)&tpp, cpu_online_mask);
        return addr;
 }
 
 #if defined(CONFIG_DYNAMIC_FTRACE) || defined(HAVE_JUMP_LABEL)
 
-unsigned char ideal_nop5[IDEAL_NOP_SIZE_5];
+#ifdef CONFIG_X86_64
+unsigned char ideal_nop5[5] = { 0x66, 0x66, 0x66, 0x66, 0x90 };
+#else
+unsigned char ideal_nop5[5] = { 0x3e, 0x8d, 0x74, 0x26, 0x00 };
+#endif
 
 void __init arch_init_ideal_nop5(void)
 {
-       extern const unsigned char ftrace_test_p6nop[];
-       extern const unsigned char ftrace_test_nop5[];
-       extern const unsigned char ftrace_test_jmp[];
-       int faulted = 0;
-
        /*
-        * There is no good nop for all x86 archs.
-        * We will default to using the P6_NOP5, but first we
-        * will test to make sure that the nop will actually
-        * work on this CPU. If it faults, we will then
-        * go to a lesser efficient 5 byte nop. If that fails
-        * we then just use a jmp as our nop. This isn't the most
-        * efficient nop, but we can not use a multi part nop
-        * since we would then risk being preempted in the middle
-        * of that nop, and if we enabled tracing then, it might
-        * cause a system crash.
+        * There is no good nop for all x86 archs.  This selection
+        * algorithm should be unified with the one in find_nop_table(),
+        * but this should be good enough for now.
         *
-        * TODO: check the cpuid to determine the best nop.
+        * For cases other than the ones below, use the safe (as in
+        * always functional) defaults above.
         */
-       asm volatile (
-               "ftrace_test_jmp:"
-               "jmp ftrace_test_p6nop\n"
-               "nop\n"
-               "nop\n"
-               "nop\n"  /* 2 byte jmp + 3 bytes */
-               "ftrace_test_p6nop:"
-               P6_NOP5
-               "jmp 1f\n"
-               "ftrace_test_nop5:"
-               ".byte 0x66,0x66,0x66,0x66,0x90\n"
-               "1:"
-               ".section .fixup, \"ax\"\n"
-               "2:     movl $1, %0\n"
-               "       jmp ftrace_test_nop5\n"
-               "3:     movl $2, %0\n"
-               "       jmp 1b\n"
-               ".previous\n"
-               _ASM_EXTABLE(ftrace_test_p6nop, 2b)
-               _ASM_EXTABLE(ftrace_test_nop5, 3b)
-               : "=r"(faulted) : "0" (faulted));
-
-       switch (faulted) {
-       case 0:
-               pr_info("converting mcount calls to 0f 1f 44 00 00\n");
-               memcpy(ideal_nop5, ftrace_test_p6nop, IDEAL_NOP_SIZE_5);
-               break;
-       case 1:
-               pr_info("converting mcount calls to 66 66 66 66 90\n");
-               memcpy(ideal_nop5, ftrace_test_nop5, IDEAL_NOP_SIZE_5);
-               break;
-       case 2:
-               pr_info("converting mcount calls to jmp . + 5\n");
-               memcpy(ideal_nop5, ftrace_test_jmp, IDEAL_NOP_SIZE_5);
-               break;
-       }
-
+#ifdef CONFIG_X86_64
+       /* Don't use these on 32 bits due to broken virtualizers */
+       if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
+               memcpy(ideal_nop5, p6_nops[5], 5);
+#endif
 }
 #endif