On Fri, Jul 18, 2025 at 11:37:36PM -0500, Jeremy Linton wrote:
> +/*
> + * Unlike put_user_gcs() above, the use of copy_from_user() may provide
> + * an opening for non GCS pages to be used to source data. Therefore this
> + * should only be used in contexts where that is acceptable.
> + */
Even in user space, the GCS pages can be read with normal loads, so
already usable as a data source if one wants to (not that it's of much
use). So not sure the comment here is needed.
> +static inline u64 load_user_gcs(unsigned long __user *addr, int *err)
Nitpick: name this get_user_gcs() for symmetry with put_user_gcs().
> +{
> + unsigned long ret;
> + u64 load = 0;
> +
> + gcsb_dsync();
Might be worth a comment here, see the one in gcs_restore_signal().
> + ret = copy_from_user(&load, addr, sizeof(load));
> + if (ret != 0)
> + *err = ret;
> + return load;
> +}
Otherwise the patch looks fine:
Reviewed-by: Catalin Marinas <catalin.mari...@arm.com>
