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From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Thu, 7 May 2020 12:17:05 +0300
Message-ID: <CAHp75VceSvk25rbbS-hmJKAgP4Xe+U6tFQDHBEA=9EHnzBH5+g@mail.gmail.com>
Subject: Re: [PATCH] x86: bitops: fix build regression
To:     David Laight <David.Laight@aculab.com>
Cc:     Brian Gerst <brgerst@gmail.com>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Sedat Dilek <sedat.dilek@gmail.com>,
        stable <stable@vger.kernel.org>,
        Jesse Brandeburg <jesse.brandeburg@intel.com>,
        "kernelci . org bot" <bot@kernelci.org>,
        Andy Shevchenko <andriy.shevchenko@intel.com>,
        Ilie Halip <ilie.halip@gmail.com>,
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        "H. Peter Anvin" <hpa@zytor.com>, Marco Elver <elver@google.com>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        "Peter Zijlstra (Intel)" <peterz@infradead.org>,
        Daniel Axtens <dja@axtens.net>,
        Masahiro Yamada <yamada.masahiro@socionext.com>,
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On Thu, May 7, 2020 at 10:50 AM David Laight <David.Laight@aculab.com> wrote:
> From: Brian Gerst
> > Sent: 07 May 2020 07:18

> > I think a better fix would be to make CONST_MASK() return a u8 value
> > rather than have to cast on every use.
>
> Or assign to a local variable - then it doesn't matter how
> the value is actually calculated. So:
>                         u8 mask = CONST_MASK(nr);

Another case with negation won't work like this I believe.
So, I thin kthe patch we have is good enough, no need to seek for an evil.

-- 
With Best Regards,
Andy Shevchenko