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 93B0A25A2CD for ; Sun, 21 Sep 2025 17:17:20 +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=1758475040; cv=none; b=Yu05PQr41nD9arOvXY8ytTIwWagQL2DwFl+Ltc6qcyO6PAn0DVxBzci+iEqM5d0TUiFhh+en6kXDLq3+fd+aj86zJRSr3QG2aMQbjuYi/9BnClgJpZNfNutORRqDG5vj5623S9+s3cvurcO6X+LfLLhntNot86jq7F9M7tIIDcY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758475040; c=relaxed/simple; bh=ouv6InRrp8mYfYW1mXwTk0wu2UATkrefzpWzVxqJ/IU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=dA4jdkuPSu1ECkHqvDJ5EaoVxhlRwv+LZDVRKwr9lLJmLdieO79Wjmo+PK+/5JV/oJXnZ10CTbjotiZQgKGM3u92gTdAA/o5vibCEtmmaiea5tgMQYOTurKoTPomPEINLZv/pwB0coIyTUCqCtOR0hUYXoXNLj+g3CToqFKjqIU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=CtmBmtt1; 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="CtmBmtt1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CE2CDC4CEE7; Sun, 21 Sep 2025 17:17:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1758475040; bh=ouv6InRrp8mYfYW1mXwTk0wu2UATkrefzpWzVxqJ/IU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=CtmBmtt11KtG8TSDlSTK1mw9LQn1yGkKby+1Xgd5w6GQ6AHAtwUkwGJ507KZ8tDF5 dfzUShivQZQAd3q4XFMd9WshOjXUxl6swvisUxEPGaCjl4+3sA+J3yM79/ukTbJ4Pr 2E1hd3lzglNJASMrOi3T4vsU/awcrBDgqAlYTu0c= Date: Sun, 21 Sep 2025 19:17:17 +0200 From: Greg KH To: Jan Kara Cc: Eric Hagberg , stable@vger.kernel.org Subject: Re: "loop: Avoid updating block size under exclusive owner" breaks on 6.6.103 Message-ID: <2025092102-passing-saxophone-d397@gregkh> References: Precedence: bulk X-Mailing-List: stable@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 Wed, Sep 17, 2025 at 05:47:16PM +0200, Jan Kara wrote: > On Wed 17-09-25 11:18:50, Eric Hagberg wrote: > > I stumbled across a problem where the 6.6.103 kernel will fail when > > running the ioctl_loop06 test from the LTP test suite... and worse > > than failing the test, it leaves the system in a state where you can't > > run "losetup -a" again because the /dev/loopN device that the test > > created and failed the test on... hangs in a LOOP_GET_STATUS64 ioctl. > > > > It also leaves the system in a state where you can't re-kexec into a > > copy of the kernel as it gets completely hung at the point where it > > says "starting Reboot via kexec"... > > Thanks for the report! Please report issues with stable kernels to > stable@vger.kernel.org (CCed now) because they can act on them. > > > If I revert just that patch from 6.6.103 (or newer) kernels, then the > > test succeeds and doesn't leave the host in a bad state. The patch > > applied to 6.12 doesn't cause this problem, but I also see that there > > are quite a few other changes to the loop subsystem in 6.12 that never > > made it to 6.6. > > > > For now, I'll probably just revert your patch in my 6.6 kernel builds, > > but I wouldn't be surprised if others stumble across this issue as > > well, so maybe it should be reverted or fixed some other way. > > Yes, I think revert from 6.6 stable kernel is warranted (unless somebody > has time to figure out what else is missing to make the patch work with > that stable branch). Great, can someone send me the revert? thanks, greg k-h