Re: [RFC v6][PATCH 3/9] x86 support for checkpoint/restart

[Cedric Le Goater <clg@fr.ibm.com>]

> +int cr_read_cpu_fpu(struct cr_hdr_cpu *hh, struct task_struct *t)
> +{
> +	struct thread_struct *thread = &t->thread;
> +
> +	/* i387 + MMU + SSE */
> +
> +	preempt_disable();
> +
> +	__clear_fpu(t);		/* in case we used FPU in user mode */
> +
> +	if (!hh->used_math)
> +		clear_used_math();
> +	else {
> +		if (hh->has_fxsr != cpu_has_fxsr) {
> +			force_sig(SIGFPE, t);
> +			return -EINVAL;
> +		}

don't you need an init_fpu() around here ? because the task you restart might 
not have used FPU yet.

> +		memcpy(&thread->xstate, &hh->xstate, sizeof(thread->xstate));

also i'd used 'xstate_size' instead of sizeof(thread->xstate)


thanks,

C.