From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 827E3C6FD18 for ; Tue, 25 Apr 2023 18:49:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234628AbjDYStJ (ORCPT ); Tue, 25 Apr 2023 14:49:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44616 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234373AbjDYStF (ORCPT ); Tue, 25 Apr 2023 14:49:05 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E6C5F16F38 for ; Tue, 25 Apr 2023 11:48:58 -0700 (PDT) Message-ID: <20230425181827.219128101@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1682448536; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc; bh=yIOPgPMU2Byq9FIQh9CetuDY5vSUSLh17oBNeM4tOuM=; b=Q7KpO9S9Qy1OKRhI3+ZciIEtNlVpVhp1KWmgtnPiAYTDFVdWPCtao9Jov7PvP2D1xkjl// UdLdE/IwhheCAvEJdoTOLnKr1JqNeoguBYX/GlnNuUjKs9oC7zZXDR9Eea6dpGR5stfFHZ ZFA6d7pTB2GXMY0hLhGzjy9TbAgp9oVu8tCKHBe5KJNCu1R1if5UY3r93ZPn1POVqwBETT pSRDrU3PXA/3oEcFMXWLec41O2zJo88lY5gzPxrZI6CNljnYLJD9n0stcQepwaT3rFzr2S hY/uvpjNkFP47ROQ7nwaaBZU5OB6Bipn4hSVIIzFeducT9wRrdrhLhoJQl1DnA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1682448536; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc; bh=yIOPgPMU2Byq9FIQh9CetuDY5vSUSLh17oBNeM4tOuM=; b=1ofOAtD2TfK3E8fNXwBEzr5oynzoO7kDcTjCxittXWe1U+xDbWVicRqWr6x2SmkJxFRCxJ x1xKqND+jNR3GFCw== From: Thomas Gleixner To: LKML Cc: Frederic Weisbecker , Anna-Maria Behnsen , Peter Zijlstra , Sebastian Siewior , syzbot+5c54bd3eb218bb595aa9@syzkaller.appspotmail.com, Dmitry Vyukov , Michael Kerrisk Subject: [patch 00/20] posix-timers: Fixes and cleanups Date: Tue, 25 Apr 2023 20:48:55 +0200 (CEST) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi! A recent syzcaller/KCSAN report about a data race and an actually broken loop termination due to that race made me look deeper into the posix timer code. Aside of the loop termination issue this unearthed another issue in the exit() path where timer deletion might livelock on RT enabled kernels. While going through the code with a fine comb, I stumbled over another place which needs READ/WRITE_ONCE() annotations, tons of outdated and/or uncomprehensible comments and a bunch of silly code. The series has therefore a larger set of cleanups on top of the two fixes. It is based on git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/core and also availble from git: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git timers/posix Thanks, tglx --- include/linux/sched/signal.h | 2 kernel/time/posix-timers.c | 523 ++++++++++++++++++++++++++----------------- 2 files changed, 321 insertions(+), 204 deletions(-)