forked from luck/tmp_suning_uos_patched
x86: Introduce hypervisor_cpuid_base()
This patch introduce hypervisor_cpuid_base() which loop test the hypervisor existence function until the signature match and check the number of leaves if required. This could be used by Xen/KVM guest to detect the existence of hypervisor. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Link: http://lkml.kernel.org/r/1374742475-2485-1-git-send-email-jasowang@redhat.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This commit is contained in:
parent
c095ba7224
commit
96e39ac0e9
|
@ -971,6 +971,21 @@ unsigned long calc_aperfmperf_ratio(struct aperfmperf *old,
|
|||
return ratio;
|
||||
}
|
||||
|
||||
static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
|
||||
{
|
||||
uint32_t base, eax, signature[3];
|
||||
|
||||
for (base = 0x40000000; base < 0x40010000; base += 0x100) {
|
||||
cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
|
||||
|
||||
if (!memcmp(sig, signature, 12) &&
|
||||
(leaves == 0 || ((eax - base) >= leaves)))
|
||||
return base;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
extern unsigned long arch_align_stack(unsigned long sp);
|
||||
extern void free_init_pages(char *what, unsigned long begin, unsigned long end);
|
||||
|
||||
|
|
Loading…
Reference in New Issue
Block a user