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| author | Ingo Molnar <mingo@elte.hu> | 2008-10-10 19:30:08 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-10-10 19:30:08 +0200 |
| commit | 3dd392a407d15250a501fa109cc1f93fee95ef85 (patch) | |
| tree | c1faca3fa8bd0f7c8790b3e0887229b4a5a90e8b /arch/x86/kernel/cpu/common.c | |
| parent | b27a43c1e90582facad44de67d02bc9e9f900289 (diff) | |
| parent | d403a6484f0341bf0624d17ece46f24f741b6a92 (diff) | |
Merge branch 'linus' into x86/pat2
Conflicts:
arch/x86/mm/init_64.c
Diffstat (limited to 'arch/x86/kernel/cpu/common.c')
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 24 |
1 files changed, 4 insertions, 20 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 8aab8517642e..4e456bd955bb 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -344,31 +344,15 @@ static void __init early_cpu_detect(void) /* * The NOPL instruction is supposed to exist on all CPUs with - * family >= 6, unfortunately, that's not true in practice because + * family >= 6; unfortunately, that's not true in practice because * of early VIA chips and (more importantly) broken virtualizers that - * are not easy to detect. Hence, probe for it based on first - * principles. + * are not easy to detect. In the latter case it doesn't even *fail* + * reliably, so probing for it doesn't even work. Disable it completely + * unless we can find a reliable way to detect all the broken cases. */ static void __cpuinit detect_nopl(struct cpuinfo_x86 *c) { - const u32 nopl_signature = 0x888c53b1; /* Random number */ - u32 has_nopl = nopl_signature; - clear_cpu_cap(c, X86_FEATURE_NOPL); - if (c->x86 >= 6) { - asm volatile("\n" - "1: .byte 0x0f,0x1f,0xc0\n" /* nopl %eax */ - "2:\n" - " .section .fixup,\"ax\"\n" - "3: xor %0,%0\n" - " jmp 2b\n" - " .previous\n" - _ASM_EXTABLE(1b,3b) - : "+a" (has_nopl)); - - if (has_nopl == nopl_signature) - set_cpu_cap(c, X86_FEATURE_NOPL); - } } static void __cpuinit generic_identify(struct cpuinfo_x86 *c) |