From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 B947925A650 for ; Fri, 17 Jan 2025 02:06:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737079587; cv=none; b=hbxcXZgsaMgnNlVKlCAMvyprU8UF/3RpEx1I8z9kcAq/7pqMNO5wNoV8vxewsTcv9iqDZUOcojIS5YfHjYZ8PUpxXf38MVEV0owPKK+wyof6DWE6F+2lw5Ov05Ng3wEQJENLdEEYM+GZho97vvY2pUBsPsrSH/2tX3xfRMsKdk8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737079587; c=relaxed/simple; bh=akDnnQ7wqGliYh98C8tN0vdkUtCMSaayV5uyJOVmVZg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=l7dURBznxSvVZkxLfnwTcFAVFCDDmoWk3PJBaCpOoQ0JSs9wObkrWE96QUJyJXM1DtHtA4c2C59wPohI55uhwWvlNlfVes7UaZqjcnRUkjyr6z7mFUQ/iiTxRbVEXYQx50c2yqKTzY612/dEKswHWFFWbZ0M/d0AxFSbB0VWgro= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EjMgdHcy; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="EjMgdHcy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2DEC7C4CED6; Fri, 17 Jan 2025 02:06:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1737079587; bh=akDnnQ7wqGliYh98C8tN0vdkUtCMSaayV5uyJOVmVZg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=EjMgdHcyO3oQQRZ+j5i6KX0p0NTsm/IlGkuABAnW7IO5z3FYBduIvE3+7Fon0im/Q g80c51N5LAQkXOT/nu5L4BwNAYCQcD73qr9t8nR/Prkxv8ScyAYlAiF/iqSoJJzowF IDRjMujJAD8m2iPZZiRpp0BkpsMNB4V/rQ7VnUH+AK+Yrbe/pYxBf/0KKGWBCgrYNi 1yrLfrK8vOc8wHiuWXNErqc/izbUu8s5Nu04n62o1SGo5VMNOmhU+dwxy5N9GcVKpH pIcLBciZo0/cl3PKM9iciN3/XJZQd9bEsv9Q3Ow9jcakIUxamPznHm8mmMFm/ggFzT SjjELG3lyB/5Q== Date: Thu, 16 Jan 2025 16:06:26 -1000 From: Tejun Heo To: Andrea Righi Cc: David Vernet , Changwoo Min , linux-kernel@vger.kernel.org, Breno Leitao Subject: Re: [PATCH] sched_ext: Fix potential deadlock in destroy_dsq() Message-ID: References: <20250116115101.549175-1-arighi@nvidia.com> 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-Disposition: inline In-Reply-To: <20250116115101.549175-1-arighi@nvidia.com> On Thu, Jan 16, 2025 at 12:51:01PM +0100, Andrea Righi wrote: > When creating and destroying DSQs concurrently, a potential deadlock can > occur due to a circular locking dependency between the locks involved in > the operations: > > - create_dsq(): > > rhashtable_bucket --> rq->lock --> dsq->lock Hmm... this is probably the same thing that Breno tried to fix with rhashtable update. Breno, what's the current state of that patch? I saw bug reports and fix patch flying by but didn't track them closely. Thanks. -- tejun