From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 962A2192D83; Wed, 5 Feb 2025 22:31:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738794689; cv=none; b=Iy8cpj49sljmeBXoa52xq2dNZfa5sSvLo9MWRkwenYqFj+BsQ2SuDv+Bs6pDzJ5dP/iAdoDh/QZUInTRVd95beHwK2b5LYQLt8PL+moJw5HHv2E3bXTnPat4kFKEKwITXlF4QanS4gXyNYoj0ySUL4iiVoNdaMNUpl9zr5QNxbs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738794689; c=relaxed/simple; bh=Vr5fU+QGCImK+vWVGfPtqObS6yfloyhPGeEb4Dfyzgo=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=JDGzLpIsAlWf83FL1xbjLr8QAmXh92pivIXTq+ylVMw7gbIS6RbfO35/HM6ckMLf8N0SAVim30pHtQ+VWUIu8SDb9JgteL8AdyqU/8y+kI69zzujVzkXaGiv0Foj2rinJ7LWeiKbAcpyKbLXzDq84cAQGcRibyUFvNaIdjKNRC4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=zcwKXQST; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=UUdlV0Sl; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="zcwKXQST"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="UUdlV0Sl" From: John Ogness DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1738794685; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Vr5fU+QGCImK+vWVGfPtqObS6yfloyhPGeEb4Dfyzgo=; b=zcwKXQSTwk6ZxwH7pJEiZaoV8bOXjB3Fju/dViMWRLbXyXAEhIwABcbv9hZZVEkPbZ7Tx5 NTTuIg/I6uH7acxoypiLQWpEa2pCugpzlDoPl7fU6OGg3t/j/RxA8iXvZ47P1i3AbUlwx/ NEJjll21TvoiVEi7PFCh6L3k2Q8tRv9Osk2J83BtIsejEJ/naxpzVJZlFGXBrz6h2Kn3Dq OA1SPFDyBzB1b96q7YcSGHIrLqe2sOH4YdYTLPa8b9OVp9b0aCm1cFg02+MjWrBKro5XUz gyuWsIyTt+sZHpiuS5fwPKvscqkaBCTpxQtHsJp2M4JrpmOk8xSTH+HggwtmMA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1738794685; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Vr5fU+QGCImK+vWVGfPtqObS6yfloyhPGeEb4Dfyzgo=; b=UUdlV0SlLMlKrCo/hZ/bp50ohZ6M4v8PVu4mKiVWogHdTmwRWAurZ141BjQ2RibtB1ldDZ T34MIDLavsqW5bBA== To: paulmck@kernel.org, Petr Mladek Cc: Sebastian Andrzej Siewior , rcu@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@meta.com, rostedt@goodmis.org, Frederic Weisbecker , Thomas Gleixner , Alexei Starovoitov , Andrii Nakryiko , Mathieu Desnoyers , Masami Hiramatsu , linux-trace-kernel@vger.kernel.org Subject: Re: [PATCH rcu v2] 4/5] rcu-tasks: Move RCU Tasks self-tests to core_initcall() In-Reply-To: <841pwc11ae.fsf@jogness.linutronix.de> References: <20250130185320.1651910-4-paulmck@kernel.org> <20250204102611.OVuHn9rS@linutronix.de> <20250204163409.ueObHFje@linutronix.de> <9ed4e0fd-75c4-400a-9a0b-74c68286bad3@paulmck-laptop> <84pljwi2w0.fsf@jogness.linutronix.de> <3a0ceabe-d5a0-4cb3-8343-ec56bc9bd0fd@paulmck-laptop> <84ed0c1401.fsf@jogness.linutronix.de> <841pwc11ae.fsf@jogness.linutronix.de> Date: Wed, 05 Feb 2025 23:37:25 +0106 Message-ID: <84y0ykyqf6.fsf@jogness.linutronix.de> Precedence: bulk X-Mailing-List: rcu@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain On 2025-02-05, John Ogness wrote: >> OK, so I don't need to add "if (IS_ENABLED(CONFIG_PREEMPT_RT))" to guard >> it, then? > > For !CONFIG_PREEMPT_RT, if there are legacy consoles registered, > pr_flush() will additionally perform a blocking lock on the > console_lock. Sorry, I was just thinking about the flushing component of pr_flush(). Later in the function it takes the console_lock even for CONFIG_PREEMPT_RT. So please do _not_ have a guard. pr_flush() should never hang on the console_lock during shutdown, but if does, that is something that will need to be debugged and fixed. @pmladek: Looking forward to reading your input on this. John