From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 DE426241E2 for ; Thu, 5 Oct 2023 13:48:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 5F2FE10D; Thu, 5 Oct 2023 06:48:18 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 9D1FB1688; Thu, 5 Oct 2023 06:38:51 -0700 (PDT) Received: from [10.34.100.116] (e126645.nice.arm.com [10.34.100.116]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 353C13F641; Thu, 5 Oct 2023 06:38:12 -0700 (PDT) Message-ID: <375571ff-c63e-9045-81ff-dc93bcade8ee@arm.com> Date: Thu, 5 Oct 2023 15:38:06 +0200 Precedence: bulk X-Mailing-List: linux-rt-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.15.1 Subject: Re: [ANNOUNCE] v6.6-rc4-rt7 To: Sebastian Andrzej Siewior , Thomas Gleixner Cc: LKML , linux-rt-users@vger.kernel.org, Steven Rostedt References: <20231004160655.0D-7XFo_@linutronix.de> Content-Language: en-US From: Pierre Gondois In-Reply-To: <20231004160655.0D-7XFo_@linutronix.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-8.4 required=5.0 tests=BAYES_00,NICE_REPLY_A, RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Hello Sebastian, The following happened once [1]. In pl011_console_write() from: commit da042bbb7a3f ("printk: Update the printk series.") &uap->port seems to be released, but various paths don't seem to acquire the lock, Regards, Pierre [1] [...] ===================================== [...] WARNING: bad unlock balance detected! [...] 6.6.0-rc4-rt7-00098-g400db4a2dd90 #1157 Not tainted [...] ------------------------------------- [...] pr/legacy/18 is trying to release lock (&port_lock_key) at: [...] pl011_console_write ([path]/drivers/tty/serial/amba-pl011.c:2366) [...] but there are no more locks to release! [...] [...] other info that might help us debug this: [...] 2 locks held by pr/legacy/18: [...] #0: ffff8000846bc0b8 (console_lock){+.+.}-{0:0}, at: nbcon_legacy_kthread_func ([path]/kernel/printk/printk.c:3052 [path]/kernel/printk/printk.c:3364) [...] #1: ffff8000846bc030 (console_srcu){....}-{0:0}, at: console_flush_all ([path]/./include/linux/srcu.h:230 [path]/kernel/printk/printk.c:286 [path]/kernel/printk/printk.c:2971) [...] [...] stack backtrace: [...] CPU: 1 PID: 18 Comm: pr/legacy Not tainted 6.6.0-rc4-rt7-00098-g400db4a2dd90 #1157 [...] Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform, BIOS EDK II Sep 5 2023 [...] Call trace: [...] dump_backtrace ([path]/arch/arm64/kernel/stacktrace.c:235) [...] show_stack ([path]/arch/arm64/kernel/stacktrace.c:242) [...] dump_stack_lvl ([path]/lib/dump_stack.c:107) [...] dump_stack ([path]/lib/dump_stack.c:114) [...] print_unlock_imbalance_bug ([path]/kernel/locking/lockdep.c:5201) [...] lock_release ([path]/kernel/locking/lockdep.c:5438 [path]/kernel/locking/lockdep.c:5780) [...] rt_spin_unlock ([path]/kernel/locking/spinlock_rt.c:81) [...] pl011_console_write ([path]/drivers/tty/serial/amba-pl011.c:2366) [...] console_flush_all ([path]/kernel/printk/printk.c:2910 [path]/kernel/printk/printk.c:2992) [...] nbcon_legacy_kthread_func ([path]/kernel/printk/printk.c:3053 [path]/kernel/printk/printk.c:3364) [...] kthread ([path]/kernel/kthread.c:388) [...] ret_from_fork ([path]/arch/arm64/kernel/entry.S:854) On 10/4/23 18:06, Sebastian Andrzej Siewior wrote: > Dear RT folks! > > I'm pleased to announce the v6.6-rc4-rt7 patch set. > > Changes since v6.6-rc4-rt6: > > - Lockdep complained about SRCU locking if printk was used from NMI. > > - The i915 driver could create a locking related splat during suspend/ > resume. Reported by John B. Wyatt IV. > > - A new version of printk. This is an update to the current > development version. Large patch series provided by John Ogness. > > Known issues > None > > The delta patch against v6.6-rc4-rt6 is not appended below due to its > size. It and can be found here: > > https://cdn.kernel.org/pub/linux/kernel/projects/rt/6.6/incr/patch-6.6-rc4-rt6-rt7.patch.xz > > and as web based diff: > > https://git.kernel.org/rt/linux-rt-devel/d/v6.6-rc4-rt7/v6.6-rc4-rt6 > > You can get this release via the git tree at: > > https://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git v6.6-rc4-rt7 > > The RT patch against v6.6-rc4 can be found here: > > https://cdn.kernel.org/pub/linux/kernel/projects/rt/6.6/older/patch-6.6-rc4-rt7.patch.xz > > The split quilt queue is available at: > > https://cdn.kernel.org/pub/linux/kernel/projects/rt/6.6/older/patches-6.6-rc4-rt7.tar.xz > > Sebastian >