Author: Vladimir Davydov Email: vdavy...@parallels.com Subject: arch: x86: check if cpuid level exists while reporting cpuinfo Date: Mon, 8 Dec 2014 12:40:42 +0300
For /proc/cpuinfo to reflect cpuid masking/faulting setup we use cpuid instruction to get some features. However, the cpuid levels may not exist, in which case cpuid'll return rubbish. Let's assure that the cpuid levels exist, just like we do in get_cpu_cap. Signed-off-by: Vladimir Davydov <vdavy...@parallels.com> Acked-by: Cyrill Gorcunov <gorcu...@openvz.org> ============================================================================= https://jira.sw.ru/browse/PSBM-33638 Signed-off-by: Vladimir Davydov <vdavy...@virtuozzo.com> --- arch/x86/kernel/cpu/proc.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c index e98290be927d..77c7c825f95d 100644 --- a/arch/x86/kernel/cpu/proc.c +++ b/arch/x86/kernel/cpu/proc.c @@ -75,10 +75,14 @@ static void init_cpu_flags(void *dummy) if (cpu_has(c, i)) set_bit(i, (unsigned long *)flags); - __do_cpuid_fault(0x00000001, 0, &tmp1, &tmp2, - &flags->val[4], &flags->val[0]); - __do_cpuid_fault(0x80000001, 0, &tmp1, &tmp2, - &flags->val[6], &flags->val[1]); + if (c->cpuid_level >= 0x00000001) + __do_cpuid_fault(0x00000001, 0, &tmp1, &tmp2, + &flags->val[4], &flags->val[0]); + + if ((c->extended_cpuid_level & 0xffff0000) == 0x80000000 && + c->extended_cpuid_level >= 0x80000001) + __do_cpuid_fault(0x80000001, 0, &tmp1, &tmp2, + &flags->val[6], &flags->val[1]); } static int show_cpuinfo(struct seq_file *m, void *v) -- 2.1.4 _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
