Re: [PATCH V3] arm64/cpufeature: Add get_arm64_ftr_reg_nowarn()

From: Catalin Marinas
Date: Wed May 27 2020 - 07:37:08 EST


On Wed, May 27, 2020 at 03:34:36PM +0530, Anshuman Khandual wrote:
> +/*
> + * get_arm64_ftr_reg - Looks up a feature register entry using
> + * its sys_reg() encoding. This calls get_arm64_ftr_reg_nowarn().
> + *
> + * returns - Upon success, matching ftr_reg entry for id.
> + * - NULL on failure but with an WARN_ON().
> + */
> +static struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id)
> +{
> + struct arm64_ftr_reg *reg;
> +
> + reg = get_arm64_ftr_reg_nowarn(sys_id);
> +
> + /*
> + * Can not really proceed when the search fails here.
> + * Requesting for a non existent register search will
> + * be an error. Warn but let it continue for now.
> + */
> + WARN_ON(!reg);
> + return reg;

I find the comment here slightly confusing: cannot proceed but continue.
Maybe something like:

/*
* Requesting a non-existent register search is an error. Warn
* and let the caller handle it.
*/

Otherwise it looks fine:

Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx>