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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Fri, 15 Sep 2023 10:04:10 -0700
Message-ID: <CAHk-=whO1+-4ALjFWSE0kzytz1kEbWPvy3xWvcUP1dJ4t-QqkA@mail.gmail.com>
Subject: Re: Buggy __free(kfree) usage pattern already in tree
To:     Alexey Dobriyan <adobriyan@gmail.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        linux-kernel@vger.kernel.org,
        Bartosz Golaszewski <bartosz.golaszewski@linaro.org>,
        Linus Walleij <linus.walleij@linaro.org>,
        akpm@linux-foundation.org
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On Fri, 15 Sept 2023 at 02:56, Alexey Dobriyan <adobriyan@gmail.com> wrote:
>
> __free() got some usage and some of the usage is buggy:

Yeah, that's sad.

I think the '__free(kfree)' thing should *only* be used in the form

        struct obj *p __free(kfree) = kmalloc(...);

which is what our docs mention. Anything else is simply buggy.

But how do we *notice* this?

I do want to stress how I was unhappy about this conversion to begin with

    https://lore.kernel.org/lkml/CAHk-=wigZt6kVkY0HU1j_LJ5H1KzwPiYnwwk6CbqXqT=sGenjg@mail.gmail.com/

but I reacted to the wrong issue.

This stuff needs to be done *way* more carefully.

              Linus