Commit 9bd01506 authored by Rusty Russell's avatar Rusty Russell Committed by Avi Kivity
Browse files

KVM: fx_init() needs preemption disabled while it plays with the FPU state 



Now that kvm generally runs with preemption enabled, we need to protect
the fpu intialization sequence.

Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent 11ec2804

drivers/kvm/kvm_main.c

+3 −0
Original line number Diff line number Diff line
@@ -693,10 +693,13 @@ void fx_init(struct kvm_vcpu *vcpu) 


	} *fx_image;



	/* Initialize guest FPU by resetting ours and saving into guest's */

	preempt_disable();

	fx_save(vcpu->host_fx_image);

	fpu_init();

	fx_save(vcpu->guest_fx_image);

	fx_restore(vcpu->host_fx_image);

	preempt_enable();



	fx_image = (struct fx_image_s *)vcpu->guest_fx_image;

	fx_image->mxcsr = 0x1f80;