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From:   Thomas Gleixner <tglx@linutronix.de>
To:     peterz@infradead.org, axboe@kernel.dk
Cc:     linux-kernel@vger.kernel.org, peterz@infradead.org,
        mingo@redhat.com, dvhart@infradead.org, dave@stgolabs.net,
        andrealmeid@igalia.com, Andrew Morton <akpm@linux-foundation.org>,
        urezki@gmail.com, hch@infradead.org, lstoakes@gmail.com,
        Arnd Bergmann <arnd@arndb.de>, linux-api@vger.kernel.org,
        linux-mm@kvack.org, linux-arch@vger.kernel.org,
        malteskarupke@web.de
Subject: Re: [PATCH v3 06/15] futex: FLAGS_STRICT
In-Reply-To: <20230921105248.048643656@noisy.programming.kicks-ass.net>
References: <20230921104505.717750284@noisy.programming.kicks-ass.net>
 <20230921105248.048643656@noisy.programming.kicks-ass.net>
Date:   Thu, 21 Sep 2023 17:14:34 +0200
Message-ID: <87y1gzh82t.ffs@tglx>
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On Thu, Sep 21 2023 at 12:45, peterz@infradead.org wrote:
> The current semantics for futex_wake() are a bit loose, specifically
> asking for 0 futexes to be woken actually gets you 1.
>
> Adding a !nr check to sys_futex_wake() makes that it would return 0
> for unaligned futex words, because that check comes in the shared
> futex_wake() function. Adding the !nr check there, would affect the
> legacy sys_futex() semantics.
>
> Hence frob a flag :-(
>
> Suggested-by: Andr=C3=A9 Almeida <andrealmeid@igalia.com>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>