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Date: Fri, 16 Jun 2017 12:58:34 +0100
From: Russell King - ARM Linux <linux@armlinux.org.uk>
To: Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org,
        Catalin Marinas <catalin.marinas@arm.com>,
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Subject: Re: [PATCH 1/3] ARM: Generalize fncpy implementation
Message-ID: <20170616115834.GZ23750@n2100.armlinux.org.uk>
References: <20170615232117.29727-1-f.fainelli@gmail.com>
 <20170615232117.29727-2-f.fainelli@gmail.com>
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On Thu, Jun 15, 2017 at 04:21:15PM -0700, Florian Fainelli wrote:
> ARM's fncpy implementation is actually suitable for a large number of
> platforms since the only assumption it makes is just the function's
> alignment (8 bytes) which also happens to fulfil other architectures,
> including but not limited to ARM64.

NAK.  This is really not "generic" because the whole point of this is
that it encapsulates architecture specific knowledge - in the case of
ARM, the fact that bit 1 is used to indicate whether the code is to be
run in Thumb mode or ARM mode.

That clearly does not belong in an asm-generic version of this.

I'm not saying "don't provide an asm-generic" version, I'm saying don't
use the ARM version as an asm-generic implementation, because it is
nothing of the sort.

-- 
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