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a=rsa-sha256; c=relaxed/relaxed; d=stgolabs.net; s=dreamhost; t=1777665913; bh=NwEsWWCqng3IvHj5K+nEOfwX+NUNjkzO+PnUqVJ5j5w=; h=Date:From:To:Cc:Subject:Content-Type; b=JKXbDsglwhwnir/WnCyj1sf9Euh1TC5V/5MksIh6LjBU0h+hpTo1Cdw4z9QjvelM1 Y3amEX8P/873OJRQcsimhFYGy72pwJLBgQQA5KEtPxQvCfnixgeE7nODfhY5zd3ADz CItSM6MA27WFOK1CHvV786EAvKQVllavlSrRWBRwPZh7O1pxpL2CAmZnqE988GwHjw 6+oTUL1Yfyvv7qSaqXz8nCgFocjslEuGwD8vonRQmA7TesnO3/HfMZoL+GciYW3MW6 FlBDmSuvNMQzaS+iPsgDSeKC/6Jnfopt/1RUpZvbuq/w0SxTie/BD2nK3qMNvbJYOL MvTbZMv5fvlvQ== Date: Fri, 1 May 2026 13:05:10 -0700 From: Davidlohr Bueso To: Linus Torvalds Cc: tglx@kernel.org, mingo@redhat.com, peterz@infradead.org, bigeasy@linutronix.de, yimingqian591@gmail.com, dvhart@infradead.org, andrealmeid@igalia.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] futex: Drop CLONE_THREAD requirement for private default hash alloc Message-ID: <20260501200510.5drtcxg4clvb6vsw@offworld> References: <20260501194123.948643-1-dave@stgolabs.net> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20220429 On Fri, 01 May 2026, Linus Torvalds wrote: >On Fri, 1 May 2026 at 12:41, Davidlohr Bueso wrote: >> >> Loosen the check to cover any CLONE_VM clone, except vfork(). Excluding >> vfork keeps the existing paths untouched (no overhead), and we can't >> race in the first place: either the parent is suspended and the child runs >> alone, or mm->futex_ref is already allocated from an earlier CLONE_THREAD. > >That "earlier CLONE_THREAD" should presumably be "earlier CLONE_VM", no? yes :)