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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Al Viro' <viro@zeniv.linux.org.uk>
CC:     Eric Dumazet <edumazet@google.com>,
        gus Gusenleitner Klaus <gus@keba.com>,
        Al Viro <viro@ftp.linux.org.uk>,
        Thomas Gleixner <tglx@linutronix.de>,
        lkml <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@redhat.com>, "bp@alien8.de" <bp@alien8.de>,
        "dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>,
        "x86@kernel.org" <x86@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        "dsahern@kernel.org" <dsahern@kernel.org>,
        "kuba@kernel.org" <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>
Subject: RE: AW: [PATCH] amd64: Fix csum_partial_copy_generic()
Thread-Topic: AW: [PATCH] amd64: Fix csum_partial_copy_generic()
Thread-Index: AQHaBG0ELw1zxmi7jUCMTwySbq0j57BVpWHg///yIICAAXFNkA==
Date:   Mon, 23 Oct 2023 08:16:59 +0000
Message-ID: <2a4555bf640e4bc4b76e1ae14e5cb5e1@AcuMS.aculab.com>
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From: Al Viro
> Sent: 22 October 2023 12:12
> 
> On Sun, Oct 22, 2023 at 11:03:39AM +0000, David Laight wrote:
> 
> > > +			return -1;
> >
> > If you are going to return -1 the return type should be signed.
> 
> It's a perfectly valid C to have return -1 in a function that
> returns unsigned long long (or any other unsigned type, really)...

It is also valid C to return a pointer :-)

I also suspect that sparse will complain massively and
require a lot of the horrid (__force) casts.
(They should really be a function so that they are completely
ignored by the compiler - unless the compiler needs a cast as well.)

	David

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