From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D3A3521CFFD; Thu, 11 Dec 2025 08:05:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765440343; cv=none; b=fksSbzn/tt6j8HWufgkYLLpHhVZbK/WDQAy18wqjOHd63wbncsFxBHu7SSpojGtl+YrKkFjISuOXf/3M6unn3UXCeo9gIwjRuNivWFXhjhOcnLT9WqmSNJtlA/XVtNFxgBSDuhRpGVvqZMVDhTLaOKHz3NMOg9o2nBAS5Ngw+Gg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765440343; c=relaxed/simple; bh=aPKeMjxLi1HLi972Uhx0X3LDVwP8dUt8WWUBTZJ2J6A=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=W4IAzqHqE/cPve2dId6NFfvQGlIW+NDS3PH6D6+DCMpsOM6rr3NQpQCBOytR9gOfBJhyfr5xthBxJbTzJ3rlXGcXXnAUAubuMrT8tFYK9ZBDs7pao4z/V/jqvCjmRcr+hoEh8/PX5sMhQiZjzym4mSLC8ximmgZfewJx+vd4NI0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=iAUDs4oI; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="iAUDs4oI" Received: from pendragon.ideasonboard.com (fs96f9c361.tkyc007.ap.nuro.jp [150.249.195.97]) by perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id C0E251352; Thu, 11 Dec 2025 09:05:33 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1765440334; bh=aPKeMjxLi1HLi972Uhx0X3LDVwP8dUt8WWUBTZJ2J6A=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=iAUDs4oIUydn6rrPRIuVUdCNUpEL+az2VKNxP9B6OPXnKkhu3klGwfLA9C8EP8VX+ QqErQWBNtYnYeQq3edS6V1ZfeWtiniXCp6Z7bQSqXtLF+prmVu3W0qloYDDPkBbzbt HH1qOdz2qK6x1jiqNGM45RMPIHhk/p3SjgtN9mEQ= Date: Thu, 11 Dec 2025 17:05:17 +0900 From: Laurent Pinchart To: Wolfram Sang Cc: Greg Kroah-Hartman , Jason Gunthorpe , Tzung-Bi Shih , Benson Leung , "Rafael J . Wysocki" , Danilo Krummrich , Jonathan Corbet , Shuah Khan , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, chrome-platform@lists.linux.dev, linux-kselftest@vger.kernel.org, Bartosz Golaszewski , Simona Vetter , Dan Williams Subject: Re: [PATCH v5 5/7] revocable: Add fops replacement Message-ID: <20251211080517.GA28411@pendragon.ideasonboard.com> References: <20251017162116.GA316284@nvidia.com> <20251020115734.GH316284@nvidia.com> <20251021121536.GG316284@nvidia.com> <20251023145131.GI262900@nvidia.com> <2025102321-struggle-fraying-52ff@gregkh> <20251211032306.GO28860@pendragon.ideasonboard.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Thu, Dec 11, 2025 at 12:47:16PM +0900, Wolfram Sang wrote: > > > Replying late to this thread, I don't think this is right for V4L2. When > > it comes to solving the .remove() vs. userspace race, I think the right > > solution is at the cdev level. > > Isn't there even prototype code from Dan Williams? > > "[PATCH 1/3] cdev: Finish the cdev api with queued mode support" > > https://lkml.org/lkml/2021/1/20/997 I mentioned that in my LPC talk in 2022 :-) I think we should merge that (or a rebased, possibly improved version of it). I've meant to try plumbing that series in V4L2 but couldn't find the time so far. -- Regards, Laurent Pinchart