[PATCH] KVM: Clean up AMD SVM debug registers load and unload

static void save_db_regs(unsigned long *db_regs)

{

#ifdef __x86_64__

	asm ("mov %%dr0, %%rax \n\t"

	     "mov %%rax, %[dr0] \n\t"

	     "mov %%dr1, %%rax \n\t"

	     "mov %%rax, %[dr1] \n\t"

	     "mov %%dr2, %%rax \n\t"

	     "mov %%rax, %[dr2] \n\t"

	     "mov %%dr3, %%rax \n\t"

	     "mov %%rax, %[dr3] \n\t"

	     : [dr0] "=m"(db_regs[0]),

	       [dr1] "=m"(db_regs[1]),

	       [dr2] "=m"(db_regs[2]),

	       [dr3] "=m"(db_regs[3])

	     : : "rax");

#else

	asm ("mov %%dr0, %%eax \n\t"

	     "mov %%eax, %[dr0] \n\t"

	     "mov %%dr1, %%eax \n\t"

	     "mov %%eax, %[dr1] \n\t"

	     "mov %%dr2, %%eax \n\t"

	     "mov %%eax, %[dr2] \n\t"

	     "mov %%dr3, %%eax \n\t"

	     "mov %%eax, %[dr3] \n\t"

	     : [dr0] "=m"(db_regs[0]),

	       [dr1] "=m"(db_regs[1]),

	       [dr2] "=m"(db_regs[2]),

	       [dr3] "=m"(db_regs[3])

	     : : "eax");

#endif

	asm volatile ("mov %%dr0, %0" : "=r"(db_regs[0]));

	asm volatile ("mov %%dr1, %0" : "=r"(db_regs[1]));

	asm volatile ("mov %%dr2, %0" : "=r"(db_regs[2]));

	asm volatile ("mov %%dr3, %0" : "=r"(db_regs[3]));

}

static void load_db_regs(unsigned long *db_regs)

{

	asm volatile ("mov %[dr0], %%dr0 \n\t"

	     "mov %[dr1], %%dr1 \n\t"

	     "mov %[dr2], %%dr2 \n\t"

	     "mov %[dr3], %%dr3 \n\t"

	     :

	     : [dr0] "r"(db_regs[0]),

	       [dr1] "r"(db_regs[1]),

	       [dr2] "r"(db_regs[2]),

	       [dr3] "r"(db_regs[3])

#ifdef __x86_64__

	     : "rax");

#else

	     : "eax");

#endif

	asm volatile ("mov %0, %%dr0" : : "r"(db_regs[0]));

	asm volatile ("mov %0, %%dr1" : : "r"(db_regs[1]));

	asm volatile ("mov %0, %%dr2" : : "r"(db_regs[2]));

	asm volatile ("mov %0, %%dr3" : : "r"(db_regs[3]));

}

static int svm_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)