From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) (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 B3C2C28850E for ; Sat, 18 Apr 2026 23:26:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.17 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776554797; cv=none; b=tI9k4duXSCGwxFJ2w6aAo1ptnOYJxs065y1x+KhBamjCAe8XH7Qh35FGDkG9LhYVT/hNsWYfrVJn9kRwiXlwloZxPNGur+CliF3Tvfdy7pNr10atUmYQBlTATxgFtgnU6I3dv9GdIP81sEzaCSow0kgex6zUVDRO6rrpUY/mMTc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776554797; c=relaxed/simple; bh=Kzy18yoSxkSTuvnokoyvbKIvdJZOYnR+vCawZyYRIpE=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ZQbijz82h3uDjDfg6ZAuu0DQlV8JxVtFm9a5knRD8G5wHiipeaJRcJgR8so1HPcpSHHJLu+/AcXokB5isN4JmjhMz/Xo4EYbgIGZniblam47Q1OCzlC7lAmnvDBJuQ67GQbshZy5NhB19+8uQrzkBhJPq60A4Jzqnh0ION9EVSk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf14.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id E2DAA58811; Sat, 18 Apr 2026 23:26:33 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf14.hostedemail.com (Postfix) with ESMTPA id F1BD12D; Sat, 18 Apr 2026 23:26:31 +0000 (UTC) Date: Sat, 18 Apr 2026 19:26:25 -0400 From: Steven Rostedt To: "Paul E. McKenney" Cc: LKML , Frederic Weisbecker , Joel Fernandes , Eric Dumazet , Kuniyuki Iwashima , Paolo Abeni , Willem de Bruijn , Yao Kai , Peter Zijlstra , Thomas Gleixner Subject: Re: [WARNING] RCU stall in sock_def_readable() Message-ID: <20260418192625.279c4e98@fedora> In-Reply-To: <3c63b4d7-9c30-4671-953c-e5d72ceba97f@paulmck-laptop> References: <20260415132722.788bbdcf@fedora> <20260417084313.010864e8@fedora> <20260417093025.38faf68d@fedora> <61264010-608d-46dd-884c-2448b65a57ed@paulmck-laptop> <20260418183657.19c00883@fedora> <3c63b4d7-9c30-4671-953c-e5d72ceba97f@paulmck-laptop> X-Mailer: Claws Mail 4.3.1 (GTK 3.24.52; x86_64-redhat-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: 1i5bz9hhzrscz1kum4xtgsx5b3c6bjkh X-Rspamd-Server: rspamout04 X-Rspamd-Queue-Id: F1BD12D X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX18BC7BBdRi+c+Upd2g3XXnf5mUQdHqJiTw= X-HE-Tag: 1776554791-511421 X-HE-Meta: U2FsdGVkX1/VDg0UaUiIkTsKEjmlInCLw0fg2u3iACI7dv/yMTuq4O3S17+QFSqmM3QvvZzvlgA= On Sat, 18 Apr 2026 16:01:49 -0700 "Paul E. McKenney" wrote: > You know, with LAZY_PREEMPT, you are supposed to get TREE_RCU, but not > PREEMPT_RCU. And that would avoid scheduling out when rcu_read_lock() > is held. > > Ah, but are you building with PREEMPT_DYNAMIC? That would do it. Yes, PREEMPT_DYNAMIC is set. I guess I can test it without it set and see if the problem goes away. If that's the case, I'll just disable that for this one test that keeps failing due to that warning. -- Steve