Commit bf70030d authored by Linus Torvalds's avatar Linus Torvalds
Browse files

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

* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, cpu: Fix X86_FEATURE_NOPL
  x86, cpu: Re-run get_cpu_cap() after adjusting the CPUID level
parents d60a2793 366d4a43

arch/x86/kernel/cpu/common.c

+10 −5
Original line number Diff line number Diff line
@@ -704,16 +704,21 @@ void __init early_cpu_init(void) 
}



/*

 * The NOPL instruction is supposed to exist on all CPUs with

 * 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.  In the latter case it doesn't even *fail*

 * reliably, so probing for it doesn't even work.  Disable it completely

 * The NOPL instruction is supposed to exist on all CPUs of 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. In the latter case it doesn't even *fail* reliably, so

 * probing for it doesn't even work. Disable it completely on 32-bit

 * unless we can find a reliable way to detect all the broken cases.

 * Enable it explicitly on 64-bit for non-constant inputs of cpu_has().

 */

static void __cpuinit detect_nopl(struct cpuinfo_x86 *c)

{

#ifdef CONFIG_X86_32

	clear_cpu_cap(c, X86_FEATURE_NOPL);

#else

	set_cpu_cap(c, X86_FEATURE_NOPL);

#endif

}



static void __cpuinit generic_identify(struct cpuinfo_x86 *c)

arch/x86/kernel/cpu/cpu.h

+1 −0
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ struct cpu_dev { 
extern const struct cpu_dev *const __x86_cpu_dev_start[],

			    *const __x86_cpu_dev_end[];



extern void get_cpu_cap(struct cpuinfo_x86 *c);

extern void cpu_detect_cache_sizes(struct cpuinfo_x86 *c);

extern void get_cpu_cap(struct cpuinfo_x86 *c);