KVM: x86: remove vcpu's CPL check in host-invoked XCR set
authorZhanghaoyu (A) <haoyu.zhang@huawei.com>
Fri, 14 Jun 2013 07:36:13 +0000 (07:36 +0000)
committerPaolo Bonzini <pbonzini@redhat.com>
Tue, 18 Jun 2013 07:55:35 +0000 (09:55 +0200)
commit764bcbc5a6d7a2f3e75c9f0e4caa984e2926e346
tree2b9f41d110d25a5132b8127fdb9ff3a18399efd4
parent77293e215edef7871a39de4b326f777bc39278ca
KVM: x86: remove vcpu's CPL check in host-invoked XCR set

__kvm_set_xcr function does the CPL check when set xcr. __kvm_set_xcr is
called in two flows, one is invoked by guest, call stack shown as below,

  handle_xsetbv(or xsetbv_interception)
    kvm_set_xcr
      __kvm_set_xcr

the other one is invoked by host, for example during system reset:

  kvm_arch_vcpu_ioctl
    kvm_vcpu_ioctl_x86_set_xcrs
      __kvm_set_xcr

The former does need the CPL check, but the latter does not.

Cc: stable@vger.kernel.org
Signed-off-by: Zhang Haoyu <haoyu.zhang@huawei.com>
[Tweaks to commit message. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
arch/x86/kvm/x86.c