Re: [PATCH] arm64/cpufeature: Move BUG_ON() inside get_arm64_ftr_reg()

From: Catalin Marinas
Date: Wed May 20 2020 - 07:49:53 EST


On Wed, May 20, 2020 at 06:52:54AM +0530, Anshuman Khandual wrote:
> There is no way to proceed when requested register could not be searched in
> arm64_ftr_reg[]. Requesting for a non present register would be an error as
> well. Hence lets just BUG_ON() when the search fails in get_arm64_ftr_reg()
> rather than checking for return value and doing the same in some individual
> callers.
>
> But there are some callers that dont BUG_ON() upon search failure. It adds
> an argument 'failsafe' that provides required switch between callers based
> on whether they could proceed or not.
>
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Will Deacon <will@xxxxxxxxxx>
> Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
> Cc: Mark Brown <broonie@xxxxxxxxxx>
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
>
> Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>

BTW, there should be no empty line between the Cc block and the SoB.

The patch looks fine. Just a note that the patch transforms a current
WARN_ON in a BUG_ON but that's fine by me.

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