From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 57C1228C03C for ; Tue, 29 Jul 2025 11:11:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753787496; cv=none; b=LzgKAszl/ykAilVtUG2Tj+B34RFkcMLuPu61GY2Vx6GfwppKdpw6Y/EiQPjUZFFvr8iVj9/yy1voILuFTcXUuK8xTq+GDnWNVes+3DQs6GCOSMDLelwE6Wrpf9VM8t8boqr7mfZrp0z1RGiF1VsDUlKT8qevUxXHjB+Z3ISQF6k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753787496; c=relaxed/simple; bh=9GZ2Bqgl50vld93WsXGVkS36eSn4MgRHsUb561y72X8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=GBXzhmoRnso1kPFSmK2joifNX45ESdfrtA8Jp6KI9Gq1R4MyXMP4yF4bMrlL7Gaa9GvX2eVpLZELFTalBxZMeEdYtOgHinFbwUkv2faUaFG6iIkkMTtXJHx6WkhZyYryawrxfwqu1hiHEmqP3TknEboDxxQzpXK/Han8U1AoWL0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ml0q76ZB; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ml0q76ZB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 10BD4C4CEEF; Tue, 29 Jul 2025 11:11:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753787495; bh=9GZ2Bqgl50vld93WsXGVkS36eSn4MgRHsUb561y72X8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ml0q76ZBoor6h2f9Wc1L9PMra1CWCypMeyY5wEyr9CcU3JqVstiMpqjV4L6ru3ERs Nbm9Vsp3HRkNglHl8FFSsViQnrOCOG0skJw9PfIwAjO+tvcd28GU0oADvliQ/1b2h/ QTDKSSKVdUdb6NO5xzMloJaE2FRNs1hWzgrKzMXbdG6xjpySQt/qZpiIcByb6reUez sA94TxOq6HEb8bA+tToghRwzBg1l4fO23AhQ36vZgVX+ei4u0PoeWg3kAcrGNi+2pb PQQARpxSBC10Nj8v9CLHQeeEEwHhtfyPbQPaDHZoOMvXIdjn7RR5VAewmd/1JX48XZ ewhOGH8rojkhA== Date: Tue, 29 Jul 2025 14:11:30 +0300 From: Leon Romanovsky To: Danilo Krummrich Cc: Sean Anderson , Greg Kroah-Hartman , Ira Weiny , linux-kernel@vger.kernel.org, "Rafael J . Wysocki" , Dave Ertman Subject: Re: [PATCH] auxiliary: Automatically generate id Message-ID: <20250729111130.GI402218@unreal> References: <20250728211022.9165-1-sean.anderson@linux.dev> <20250729100132.GH402218@unreal> 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 Content-Disposition: inline In-Reply-To: On Tue, Jul 29, 2025 at 12:51:42PM +0200, Danilo Krummrich wrote: > On Tue Jul 29, 2025 at 12:01 PM CEST, Leon Romanovsky wrote: > > On Tue, Jul 29, 2025 at 11:36:27AM +0200, Danilo Krummrich wrote: > >> On Mon Jul 28, 2025 at 11:10 PM CEST, Sean Anderson wrote: > >> > As it turns out, ids are not allowed to have semantic meaning. Their > >> > only purpose is to prevent sysfs collisions. To simplify things, just > >> > generate a unique id for each auxiliary device. Remove all references to > >> > filling in the id member of the device. > >> > > >> > Signed-off-by: Sean Anderson > >> > --- > >> > > >> > drivers/base/auxiliary.c | 32 +++++++++++++++++++++++--------- > >> > include/linux/auxiliary_bus.h | 26 ++++++++------------------ > >> > 2 files changed, 31 insertions(+), 27 deletions(-) > >> > > >> > diff --git a/drivers/base/auxiliary.c b/drivers/base/auxiliary.c > >> > index dba7c8e13a53..f66067df03ad 100644 > >> > --- a/drivers/base/auxiliary.c > >> > +++ b/drivers/base/auxiliary.c > >> > @@ -264,6 +264,8 @@ static const struct bus_type auxiliary_bus_type = { > >> > .pm = &auxiliary_dev_pm_ops, > >> > }; > >> > > >> > +static DEFINE_IDA(auxiliary_id); > >> > >> I think this is the correct thing to do, even though the per device IDA drivers > >> typically went for so far produces IDs that are easier to handle when debugging > >> things. > >> > >> > + > >> > /** > >> > * auxiliary_device_init - check auxiliary_device and initialize > >> > * @auxdev: auxiliary device struct > >> > @@ -331,20 +333,37 @@ int __auxiliary_device_add(struct auxiliary_device *auxdev, const char *modname) > >> > return -EINVAL; > >> > } > >> > > >> > + ret = ida_alloc(&auxiliary_id, GFP_KERNEL); > >> > + if (ret < 0) { > >> > + dev_err(dev, "auxiliary device id_alloc fauiled: %d\n", ret); > >> > + return ret; > >> > + } > >> > + auxdev->id = ret; > >> > >> This overwrites the ID number set by various drivers that (still) use the > >> auxiliary_device_init() and auxiliary_device_add() pair. > >> > >> While I agree with the general intent, I think it's a very bad idea to just > >> perform this change silently leaving drivers with their IDA instances not > >> knowing that the set ID numbers do not have an effect anymore. > >> > >> I think this should be multiple steps: > >> > >> (1) Remove the id parameter and force an internal ID only for > >> auxiliary_device_create(). > >> > >> (2) Convert applicable drivers (and the Rust abstraction) to use > >> auxiliary_device_create() rather than auxiliary_device_init() and > >> auxiliary_device_add(). > >> > >> (3) Treewide change to force an internal ID for all auxiliary devices > >> considering this change in all affected drivers. > > > > I would suggest easier approach. > > 1. Add to the proposal patch, the sed generated line which removes auxdev->id > > assignment in the drivers. > > Something like this from mlx5: > > - sf_dev->adev.id = id; > > > > 2. Add standalone patches to remove not used ida_alloc/ida_free calls > > from the drivers. > > I assume you suggest this as an alternative to (3) above? If so, that's what I > meant in (3), I should have written "treewide series" instead of "treewide > change". I would say for all steps. Very important reason to use auxiliary_device_init() and not auxiliary_device_create() is to bind custom release callback, which is needed to release private data. In addition, complex devices embed struct auxiliary_device in their internal struct to rely on container_of to access the data. See mlx5_sf_dev_add() in drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c as an example. > > Technically (2) is orthogonal, yet I think it's a bit better to do the desired > change right away. Otherwise we end up converting all applicable drivers to > implement the auxiliary device release callback (which we need for a common > ida_free()) first, just to remove it later on when we convert to > auxiliary_device_create(). My expectation is to see extension of driver/base/core.c. Something like that: diff --git a/drivers/base/core.c b/drivers/base/core.c index cbc0099d8ef24..63847c84dbdc0 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -2560,8 +2560,10 @@ static void device_release(struct kobject *kobj) kfree(dev->dma_range_map); - if (dev->release) + if (dev->release) { + dev->bus_specific_cleanup(dev); dev->release(dev); + } else if (dev->type && dev->type->release) dev->type->release(dev); else if (dev->class && dev->class->dev_release) (END)