From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.itouring.de (mail.itouring.de [85.10.202.141]) (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 278511FBE8C; Wed, 25 Jun 2025 08:08:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=85.10.202.141 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750838905; cv=none; b=PuBFmpzyUU+PLilhhVp0K2H5SeuxQDKOp/Mi8sRUOq9gI/S/ppjQTP9OX5j24gbEt2QLqxHw58UZR/2O2KdkoeT3tXLC1vQZZ0EOt9o8xkAVfwV6ZTUIV/i518UeBK/XQCqEoyVhg6/nxVqJmnYxAVx3cKFC805mD29stBVtrAI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750838905; c=relaxed/simple; bh=JAxf1CaBgAJOl5eOA6B44Q1dBB+pzL1QrV464SHm514=; h=Subject:To:Cc:References:From:Message-ID:Date:MIME-Version: In-Reply-To:Content-Type; b=JOzuYmTjF5acamsqqZGblnI9G/yeBT/CPvUOy1SLN+tMFmRAbj7eFi4g8cy9qwNQ9x8YDb7wSCPaZ+Ve2+SAYEIaUFMusAnYyk/L7Rf64iHQb+bHRpogLR0+fHiaGCMotrvY24U2oIyNERwipT95YJwIIdSrYImo3PLneAWGuKA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=applied-asynchrony.com; spf=pass smtp.mailfrom=applied-asynchrony.com; arc=none smtp.client-ip=85.10.202.141 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=applied-asynchrony.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=applied-asynchrony.com Received: from tux.applied-asynchrony.com (p5b347a18.dip0.t-ipconnect.de [91.52.122.24]) by mail.itouring.de (Postfix) with ESMTPSA id C0FE1C28E; Wed, 25 Jun 2025 10:00:57 +0200 (CEST) Received: from [192.168.100.221] (hho.applied-asynchrony.com [192.168.100.221]) by tux.applied-asynchrony.com (Postfix) with ESMTP id 639BD6018BEA5; Wed, 25 Jun 2025 10:00:56 +0200 (CEST) Subject: Re: [PATCH 6.15 000/588] 6.15.4-rc2 review To: Greg Kroah-Hartman , stable@vger.kernel.org Cc: patches@lists.linux.dev, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, linux@roeck-us.net, shuah@kernel.org, patches@kernelci.org, lkft-triage@lists.linaro.org, pavel@denx.de, jonathanh@nvidia.com, f.fainelli@gmail.com, sudipm.mukherjee@gmail.com, srw@sladewatkins.net, rwarsow@gmx.de, conor@kernel.org, hargar@microsoft.com, broonie@kernel.org, Christian Brauner References: <20250624121449.136416081@linuxfoundation.org> From: =?UTF-8?Q?Holger_Hoffst=c3=a4tte?= Organization: Applied Asynchrony, Inc. Message-ID: Date: Wed, 25 Jun 2025 10:00:56 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: <20250624121449.136416081@linuxfoundation.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit (cc: Christian Brauner> Since 6.15.4-rc1 I noticed that some KDE apps (kded6, kate (the text editor)) started going into a tailspin with 100% per-process CPU. The symptom is 100% reproducible: open a new file with kate, save empty file, make changes, save, watch CPU go 100%. perf top shows copy_to_user running wild. First I tried to reproduce on 6.15.3 - no problem, everything works fine. After checking the list of patches for 6.15.4 I reverted the anon_inode series (all 3 for the first attempt) and the problem is gone. Will try to reduce further & can gladly try additional fixes, but for now I'd say these patches are not yet suitable for stable. thanks Holger