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 5DBB63D60; Wed, 3 Apr 2024 18:40:09 +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=1712169609; cv=none; b=X+5s3LUgijZ3+giboivTlkoJzVB4Axzv/wtAQHcRerD3lrUt7IPCDv/+4CaIvwBb2aV9wctigDpeNykQHlXkNEE+6DwtK7diYDwgFyD5SqRBvRL49CTnGI7IzPE7XVGK4yPKC9ExzpwEu3hC4i7sVcLjl1rtd9fQT2Z/KujfbXw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712169609; c=relaxed/simple; bh=mKkzeEBBqz/gTib0prGhwYPBjEjT54fc9L8qJ/6eNa4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=HnI9BfYzaeYnXjGeLMqgOwVtYKkyRymfFZUPA7Hl0pQ3goHEnRyIUdVGppK7UtHWFfBluCsC0aVWJjjrrcvH3SpDm2UbPtt1nNcdjg0YrtVrSCVIReMsU/34WjgQyVSN9+jqsuRpmqdKvhK2rvZVfuOvi5sbFDkNytST5z65K0g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=aHZAKSuQ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="aHZAKSuQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3D9DBC43390; Wed, 3 Apr 2024 18:40:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712169608; bh=mKkzeEBBqz/gTib0prGhwYPBjEjT54fc9L8qJ/6eNa4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=aHZAKSuQLrIMeawocgg7tTb81IdEGpoLVz2877APmYB6mWEaK/+7np/LYaTVDWZ0P 5lJVwlG/isNM3Xpc2E/EngdydGC/JakmnkqCQZMptz/L9LctvaWGyFycnQdd2IwDh+ MoDjVrNlb95usgW8HiCH/Uc8erJaxCiFzrcsyoGM= Date: Wed, 3 Apr 2024 20:40:00 +0200 From: Greg KH To: Joseph Salisbury Cc: hch@lst.de, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, axboe@kernel.dk, sashal@kernel.org, stable@vger.kernel.org, Francis Ginther Subject: Re: [v5.15 Regression] block: rename GENHD_FL_NO_PART_SCAN to GENHD_FL_NO_PART Message-ID: <2024040306-putdown-grain-daf7@gregkh> References: <924449dc-9b1f-4943-afe3-a68c03aedbb5@canonical.com> <2024040329-unstopped-spelling-64c8@gregkh> 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=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Wed, Apr 03, 2024 at 02:06:28PM -0400, Joseph Salisbury wrote: > > > On 4/3/24 13:54, Greg KH wrote: > > On Wed, Apr 03, 2024 at 01:50:09PM -0400, Joseph Salisbury wrote: > > > Hi Christoph, > > > > > > A kernel bug report was opened against Ubuntu [0].  This bug is a regression > > > introduced in mainline version v5.17-rc1 and made it's way into v5.15 stable > > > updates. > > > > > > The following commit was identified as the cause of the regression in 5.15: > > > > > > c6ce1c5dd327 ("block: rename GENHD_FL_NO_PART_SCAN to GENHD_FL_NO_PART") > > How is renaming a define a "regression"? > The "regression" is experienced after upgrading to the kernel to the version > that introduced this commit. > The v5.15.131 kernel works as expected, upgrading the kernel to v5.15.132 > breaks behavior that worked in a prior kernel version. > Reverting commit c6ce1c5dd327 in v5.15.132 allows the experience to be as > before in v5.15.131. What "experience" are you talking about here? Please be specific. What exactly "broke", what is the build error that happens? > > > I was hoping to get your feedback, since you are the patch author. Is the > > > best approach to revert this commit, since many third parties rely on the > > > name being GENHD_FL_NO_PART_SCAN in kernel headers? > > External kernel modules are never an issue. Is this a userspace thing? > > > > >  Is there a specific need that you know of that requires this commit > > > in the 5.15 and earlier stable kernels? > > Yes. And Christoph did not do the backport, so I doubt he cares :) > > > > Again, what in-kernel issue is caused by this? > > Third party code that relies on the kernel-headers will no longer compile > due to the name change.  Should we not care if we break things, even in > userspace? Is this userspace, or is it kernel drivers? If kernel drivers, you know that there s no stable kernel api, we rename and change things all the time, even in stable kernel trees, for good reasons (see the set of patches that were applied that contained this change.) Do you want to have unfixed security issues, or do you want a secure kernel that happens to rename variables at times? If userspace, please point me at this and why hasn't it broken in newer kernel releases where this change came from? thanks, greg k-h