From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.zeus03.de (zeus03.de [194.117.254.33]) (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 6DDA94657F2 for ; Thu, 26 Feb 2026 20:21:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=194.117.254.33 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772137308; cv=none; b=eZUoBCst2h5L06rG5dFywgJBMDYMz/PpG4iRUWiMsoRhzs+5qTnRtbFkTSMDyKQF05bZzOECjeRrW+vK9NZ1kkhlFO355xGru3ub/kE89jpk6sx86uBeVpubKkk9SUfQ0y0X9AoFSUjcCFxgOPFeJ16ZbPGb8p8gJx+moKBZRK0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772137308; c=relaxed/simple; bh=1rzXXS9yuR4tlmEDkuB1s97i7zkm4/SxNu7Qk8Q4eKI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=hMF0XFvwurPbjV3fTMHUnbrkOffmHuYm/xIaItiXiWlZkA0IYYNgwvLr2h1aDbHOjLnc+3BxEXgut9QU3qP0Xj48HOsfrBRWxPt1B+Uc/tw/AmNQ4pL5QSHQWcckMVsubr6vJ1+BvW9wyNL2Fw/Z8t2pZZelqT9z3j/j7M/KjEg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sang-engineering.com; spf=pass smtp.mailfrom=sang-engineering.com; dkim=pass (2048-bit key) header.d=sang-engineering.com header.i=@sang-engineering.com header.b=eeYG9FwR; arc=none smtp.client-ip=194.117.254.33 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sang-engineering.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sang-engineering.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=sang-engineering.com header.i=@sang-engineering.com header.b="eeYG9FwR" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= sang-engineering.com; h=date:from:to:cc:subject:message-id :references:mime-version:content-type:in-reply-to; s=k1; bh=Zbfz S89JWVR35E98rC5lcOrcboNxD6VC9rm/fk4PuH4=; b=eeYG9FwRG0mF2I+WxzL1 HGUVggUjRhJIyqBUgN423pjLFOP3EUNQMylCmEbSZGMmely6B7Su6xr33ZSTAz27 SHnHjRn+9CBdL1Z5essMXvI9XzDXsz+428ZavPheXWtpy/EERqut52qTJGYgLInj 1cPeVACjybOFSolGqBL66SBDtoill7iLu9mR53JzlthU1P2siXpr4UvDoiwBZK4P D+ZMgeqjfaj43lU0FiQfg2DtV2v1koFsm8uL49Ad9xjswrOn2+549Br4yoMLqJxK 9GzPFpASEH9OL6r96XiSCy8XkQ0v/gCyT3gjRNbBaPRYGavOshN70z8O6k1xV87h TA== Received: (qmail 1209289 invoked from network); 26 Feb 2026 21:21:36 +0100 Received: by mail.zeus03.de with UTF8SMTPSA (TLS_AES_256_GCM_SHA384 encrypted, authenticated); 26 Feb 2026 21:21:36 +0100 X-UD-Smtp-Session: l3s3148p1@f2ID3r9LPOkujnuU Date: Thu, 26 Feb 2026 21:21:35 +0100 From: Wolfram Sang To: Bartosz Golaszewski Cc: Andi Shyti , Chen-Yu Tsai , Jernej Skrabec , Samuel Holland , Khalil Blaiech , Asmaa Mnebhi , Jean Delvare , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , Andreas =?utf-8?Q?F=C3=A4rber?= , Manivannan Sadhasivam , Mauro Carvalho Chehab , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev, linuxppc-dev@lists.ozlabs.org, linux-actions@lists.infradead.org, Bartosz Golaszewski , linux-media@vger.kernel.org Subject: Re: [PATCH v2 00/13] i2c: add and start using i2c_adapter-specific printk helpers Message-ID: References: <20260223-i2c-printk-helpers-v2-0-13b2a97762af@oss.qualcomm.com> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260223-i2c-printk-helpers-v2-0-13b2a97762af@oss.qualcomm.com> On Mon, Feb 23, 2026 at 09:59:29AM +0100, Bartosz Golaszewski wrote: > It's been another year of discussing the object life-time problems at > conferences. I2C is one of the offenders and its problems are more > complex than those of some other subsystems. It seems the revocable[1] > API may make its way into the kernel this year but even with it in > place, I2C won't be able to use it as there's currently nothing to > *revoke*. The struct device is embedded within the i2c_adapter struct > whose lifetime is tied to the provider device being bound to its driver. > > Fixing this won't be fast and easy but nothing's going to happen if we > don't start chipping away at it. The ultimate goal in order to be able > to use an SRCU-based solution (revocable or otherwise) is to convert the > embedded struct device in struct i2c_adapter into an __rcu pointer that > can be *revoked*. To that end we need to hide all dereferences of > adap->dev in drivers. > > This series addresses the usage of adap->dev in device printk() helpers > (dev_err() et al). It introduces a set of i2c-specific helpers and > starts using them across bus drivers. For now just 12 patches but I'll > keep on doing it if these get accepted. Once these get upstream for > v6.20/7.0, we'll be able to also start converting i2c drivers outside of > drivers/i2c/. I applied the series to for-current but squashed the user conversions into patch 1. Changes are trivial enough and I don't want the pull request to look excessive, so it can go in smoothly. Hope you are fine with it.