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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Fri, 4 Aug 2023 11:14:07 -0700
Message-ID: <CAHk-=whr-iSsxEZ4fYfkQzs7XQN=aQhbZQKGEMnZiGdrDgLKPQ@mail.gmail.com>
Subject: Re: [PATCH v3 5/5] minmax: Relax check to allow comparison between
 int and small unsigned constants.
To:     David Laight <David.Laight@aculab.com>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        Christoph Hellwig <hch@infradead.org>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>
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On Fri, 4 Aug 2023 at 03:56, David Laight <David.Laight@aculab.com> wrote:
>
> Convert constants between 0 and INT_MAX to 'int' prior to comparisons
> so that min(signed_var, 20u) and, more commonly, min(signed_var, sizeof())
> are both valid.

I really think this whole series is broken.

What does the "are both valid" even *MEAN*?

It's simply not valid to do a "min(int, 20u)". What is the meaning of
it? You seem to think that the meaning is to do the operation in
"int". Why?

You made up a definition of "valid" that I think is completely invalid.

                Linus