> +int cr_kwrite(struct cr_ctx *ctx, void *buf, int count)
> +{
> + mm_segment_t oldfs;
> + int ret;
> +
> + oldfs = get_fs();
> + set_fs(KERNEL_DS);
> + ret = cr_uwrite(ctx, buf, count);
> + set_fs(oldfs);
> +
> + return ret;
> +}
get_fs()/set_fs() always feels a bit ouch, and this way you have to use __force to avoid the warnings about __user pointer casts in sparse. I wonder if you can use splice_read/splice_write to get around this problem.