From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f48.google.com (mail-wm1-f48.google.com [209.85.128.48]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6FD613BFE26 for ; Wed, 22 Apr 2026 08:39:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.48 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776847154; cv=none; b=HEhdmvU7EFZ8Aya+k/hwflhbaTZjdY0xPpaDeECBIAlaofXA0lGGpsK52bUCWiY/Ng8rje51M+P8wz3aJNJqMMW+vDidLJgc+xKr19TnkYvQzGKvFomfFAOQvSGpVSUPBgUzNloCgpz6GbU5JDEVAkCqMHjglEOJqQL8Shl5rM0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776847154; c=relaxed/simple; bh=aD5ZKvzwCJWOAYfguqrWQTS2cpGeKYz2zFLAh1cyFuE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Km7Z0mzr0B6ZZ9vKJgJ57OIiFmwRT9L3LcuoSSuCoSg1NVyRNspArbbYNrJmstGVectSnWlTSISwjAroEaR9nEpS3OhvixRZhFuPAjVgjfe2iy22ZC8u/88QgEmZSByV91UUhADeFXHuRQHU2jNYjBcunM/eIzNUJ7stFn3gLPA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=baylibre.com; spf=pass smtp.mailfrom=baylibre.com; dkim=pass (2048-bit key) header.d=baylibre-com.20251104.gappssmtp.com header.i=@baylibre-com.20251104.gappssmtp.com header.b=v1YTomew; arc=none smtp.client-ip=209.85.128.48 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=baylibre.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=baylibre.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=baylibre-com.20251104.gappssmtp.com header.i=@baylibre-com.20251104.gappssmtp.com header.b="v1YTomew" Received: by mail-wm1-f48.google.com with SMTP id 5b1f17b1804b1-488b0e1b870so84839645e9.2 for ; Wed, 22 Apr 2026 01:39:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20251104.gappssmtp.com; s=20251104; t=1776847152; x=1777451952; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=aD5ZKvzwCJWOAYfguqrWQTS2cpGeKYz2zFLAh1cyFuE=; b=v1YTomew26XxGa7wn6+QxxofnmzDY8MG8Q6rSlhbD8KbXbHX3swtg4/aqHuKZEt5Ml 5orPpH3A2YbkTX3LYpLEkerb58BPIUXoi+kYvqmVcgE/6QGws87PHA8mbzxqfVBLLihO GFXGG0HV2wRSCNebZG7x1mB6lZ8pamVNKzxYgwGcr5lAEQccQYtCNnwFlWrTCTU+3yOD n+2asT2SpzYDKVgGMCpnHu24R1rhDkcIqSL/6DE+q3ogCvfIPhS/gTpKhm9T9AVPIEBa KXMaWwS4onPU15IoQv4TVWG2sEILmc5unmE+wcltWJ95wMM8f/RmGQE0KlCYjxgVQHJx uQwg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776847152; x=1777451952; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=aD5ZKvzwCJWOAYfguqrWQTS2cpGeKYz2zFLAh1cyFuE=; b=Qs+hYybp7Mng75rQRDKVoVKWSZ4aAgbEm8shdK7lEVrz5uMbONxGpZ7KTcfRe8Fk8J AX1ZlojmoGUXynjrr41wPsUCCRhLnRgb0cwDXTXiR0kKgYOQNLol/azzd1r2Ref7zgK9 DzRwuDBl1ssQjB99SmOUMrKlxeMC66cBxRSWYiBxs0htDzogFfHleMqddfuk6M6Mkrzb AFEnkoN1BPUFtwfytClQT2WN06m1CE7RYn6VPgXv+jn08hHd++KzQ51VssdJWknCK5lE Hljy9udCpO5IAZUASWKJ61ME4DyAeWxe5Vp8SRUxgQZsXA3xxaqvGC28uLVYNKRCE3Wi hfQg== X-Forwarded-Encrypted: i=1; AFNElJ9IzWX+ovQH1zREHXjNUl2T3YEAfWpBtSucF/VJk+BuDh8BzzBjDelEZDJFz4XBU2DSNChqJL3a4YrkfmqSLg==@vger.kernel.org X-Gm-Message-State: AOJu0YyR6ABa7WhcHykfPes32UbMGlqjZgDvOp3e5jMUsacvUaZl+2Na cbCc48BeJ1QcKFh08xobvDSCUIqQ11cPtSIJoitStzvGmaBeIvsKHqVqsXEj9T1KjUU= X-Gm-Gg: AeBDiesoBsSPpuqUutM9M9kpuQ7Y8YIXD7MJlf3YNR5KnfJ1hR3MuE/STBX76IwQOQW ilHMEp3v7m2YbVDGv3vg+9NfSXQuupMHJL+sUe0FkJ30r8z+zv75JOG182JuYpn9Vpemrb0wL56 xF1W5NTUCaaB7gCuh6gUCyPOg8VmuKLHbieHUxD5SlkgOmdxeHOz9O8Q6BwEXImAYRSRSeTj0fU ht0iOxMryXAmrRKA296Izk8LWosOuZm51wrnZ/o1Qd3zocLxqhyH+Up65MQiYn0k+ag2aSjnYNK 95q3fM3WCZ4Da2jx15eWSKT9XfujVxNPtzggjB9OMWyzz4hJYZEJLdjdybjqA9Sl4gwM1fwqdF3 eHanWcl7ujWq+VrqsO2ksFrPdTFaGXtbokiDPtCWoJzkaCfokS9iFo91YKmfSpNbmk2ZlvKMmv5 VInHYgduUoKcoWNUmVHA0cPQVZEV7z4OdfQ2AsNFWBO1kW9E30SxQpgLmDK9C61a9GzFMhqIZM6 +TtWTKiqXPoX76GVs2dR+nDFA== X-Received: by 2002:a05:600c:890c:b0:487:1108:48af with SMTP id 5b1f17b1804b1-488fb7389a6mr245381575e9.4.1776847151437; Wed, 22 Apr 2026 01:39:11 -0700 (PDT) Received: from localhost (p200300f65f114e08a760282010012dc7.dip0.t-ipconnect.de. [2003:f6:5f11:4e08:a760:2820:1001:2dc7]) by smtp.gmail.com with UTF8SMTPSA id 5b1f17b1804b1-488fc0f8188sm455887645e9.2.2026.04.22.01.39.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 22 Apr 2026 01:39:10 -0700 (PDT) Date: Wed, 22 Apr 2026 10:39:09 +0200 From: Uwe =?utf-8?Q?Kleine-K=C3=B6nig_=28The_Capable_Hub=29?= To: Andy Shevchenko Cc: Luiz Augusto von Dentz , Ulf Hansson , "Christian A. Ehrhardt" , linux-mmc@vger.kernel.org, Greg Kroah-Hartman , Wolfram Sang , linux-kernel@vger.kernel.org, Marcel Holtmann , linux-bluetooth@vger.kernel.org, Matthias Brugger , AngeloGioacchino Del Regno , linux-mediatek@lists.infradead.org, Ping-Ke Shih , linux-wireless@vger.kernel.org, Felix Fietkau , Lorenzo Bianconi , Ryder Lee , Shayne Chen , Sean Wang , Brian Norris , Francesco Dolcini Subject: Re: [PATCH v1 1/6] sdio: Add syntactic sugar to store a pointer in sdio_driver_id Message-ID: References: Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="vqsqetyrnjrxwten" Content-Disposition: inline In-Reply-To: --vqsqetyrnjrxwten Content-Type: text/plain; protected-headers=v1; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Subject: Re: [PATCH v1 1/6] sdio: Add syntactic sugar to store a pointer in sdio_driver_id MIME-Version: 1.0 On Wed, Apr 22, 2026 at 09:52:11AM +0300, Andy Shevchenko wrote: > On Tue, Apr 21, 2026 at 10:12:41AM +0200, Uwe Kleine-K=C3=B6nig (The Capa= ble Hub) wrote: > > On Mon, Apr 20, 2026 at 04:46:56PM -0400, Luiz Augusto von Dentz wrote: > > > On Mon, Apr 20, 2026 at 4:31=E2=80=AFPM Uwe Kleine-K=C3=B6nig (The Ca= pable Hub) > > > wrote: > > > > On Fri, Apr 17, 2026 at 03:10:47PM +0200, Uwe Kleine-K=C3=B6nig (Th= e Capable Hub) wrote: > > > > > On all current Linux architectures sizeof(long) =3D=3D sizeof(voi= d *) and > > > > > this is used a lot through the kernel. For example it enables the= usual > > > > > practice to store pointers in sdio_driver_id's .driver_data membe= r. > > > > > > > > > > This works fine, but involves casting and thus isn't type-safe. > >=20 > > To be honest, with the involved void* this isn't really type-safe > > either, but at least the data keeps being a pointer which is really > > helpful on CHERI. FTR: The alternative would be to use uintptr_t instead > > of unsigned long, which also has proponents in the CHERI community and > > which is used in the current vendor patch stack. >=20 > FWIW, Linus categorically told that it has to be no uintptr_t in the Linu= x kernel. Then I'm lucky that this patch set doesn't introduce uintptr_t and so we can delay the discussion with Linus about that. (And we will have to hold that discussion at some point, because on CHERI we have sizeof(unsigned long) =3D 8 < sizeof(void *) =3D 16. I didn't check, but I think also unsigned long long cannot hold a void*. Best regards Uwe --vqsqetyrnjrxwten Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEP4GsaTp6HlmJrf7Tj4D7WH0S/k4FAmnoiSsACgkQj4D7WH0S /k74eggAtKiYZRohFpdNo44fvylrlq/Mfus5ZHYrI8EWLZuC+qMr7/LiHwZ8cxVQ atxZNwrK0qRyfjUM/lFUKvVOSQwTQzqaMGF0dNjfTVALktKCe6sLNr+gOXDqofhx UZn90knvTDOO5WfcrIf1K/ojUlgsGJ/4r63JkF3ZXPn8I3zd3NFFjhgn/ZzJkx74 5CJywELP1+kmz3pLRw0rHztfMl3gmPTsxCWqHmxLNsNtSVskl2dRZH9FMfvNKCQo KwuE7hCxtAWO4py/igcaNXz/fS0nMSCqIo3IbxAzqfJAnHgPpGrvAKSOB4GLVCoc hmaPoy6M67vqAg5NjGB4uniPlgvymw== =8Fwl -----END PGP SIGNATURE----- --vqsqetyrnjrxwten--