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 X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 38B0CC433B4 for ; Mon, 17 May 2021 15:02:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 16F9E61350 for ; Mon, 17 May 2021 15:02:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241991AbhEQPD2 (ORCPT ); Mon, 17 May 2021 11:03:28 -0400 Received: from mail-pj1-f42.google.com ([209.85.216.42]:43714 "EHLO mail-pj1-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241821AbhEQPBZ (ORCPT ); Mon, 17 May 2021 11:01:25 -0400 Received: by mail-pj1-f42.google.com with SMTP id ep16-20020a17090ae650b029015d00f578a8so3864282pjb.2 for ; Mon, 17 May 2021 08:00:09 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=l6wX7YF6aEITSh924zLIZTHI6f81+b7oIJfr5LbdEhI=; b=FKVbkEMjNavk1TjyL5vG1gm6Fol7B5lU/HbOrictw7P4XZ5BYw9jJpmcYTlD/ctZPQ +F/ujq7F0IYSjXc8SK5cNFmZLJ3eOlFwDX5IJBn81JmyZIOiKZMHRhAFGIKvotogOBAf +5wFR7p5raadoVyB4aEES4SRI/7n/NRpXmEnf0x6FTpvNaO6y/J0leRoW1Z++qmfNkbz t7XDaH6pc/oVXKxd5+QKb3WK4sWoUJ8UayDAlAAtKnPilddDtfHOTDFPGr18PYK6TchP MxfFhenFT+gdOelzS8/Alpt4dY5sWio6DJ7B3EOkxNLmuIKIsytEFJWLq0kPCKVKGVLq gBKw== X-Gm-Message-State: AOAM530f0HlHm9DMz4vistoYatOlLt7zIVkS1CEVSa1MsNrb+6DC2Hjs 5WOzWmpYTQntjKRj7YX12BU= X-Google-Smtp-Source: ABdhPJxUP1f0OsrkPOQRzAFheomEeQeeqOc7pc/6OS54fXeh4y3yKLcGex/EQID9z1769wBtD97umg== X-Received: by 2002:a17:90b:1244:: with SMTP id gx4mr360488pjb.210.1621263609107; Mon, 17 May 2021 08:00:09 -0700 (PDT) Received: from ?IPv6:2601:647:4000:d7:8224:c0d6:d9dd:57b3? ([2601:647:4000:d7:8224:c0d6:d9dd:57b3]) by smtp.gmail.com with ESMTPSA id b15sm10166188pfi.100.2021.05.17.08.00.07 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 17 May 2021 08:00:08 -0700 (PDT) Subject: Re: warning on PREEMPT_RT kernel To: Maurizio Lombardi , target-devel@vger.kernel.org Cc: bostroesser@gmail.com, michael.christie@oracle.com, martin.petersen@oracle.com References: From: Bart Van Assche Message-ID: <8b2cee4d-76d0-54bb-2f1e-df2b06aeb036@acm.org> Date: Mon, 17 May 2021 08:00:07 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: target-devel@vger.kernel.org On 5/17/21 5:39 AM, Maurizio Lombardi wrote: > static bool > __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop, > bool *aborted, bool *tas, unsigned long *flags) > __releases(&cmd->t_state_lock) > __acquires(&cmd->t_state_lock) > { > > assert_spin_locked(&cmd->t_state_lock); > WARN_ON_ONCE(!irqs_disabled()); <---------- > > I guess this is due to the fact that on realtime kernels spin_lock_irq*() do not > disable the interrupts, so the call to irqs_disabled() returns false. It's probably fine to leave out that WARN_ON_ONCE() call. And the assert_spin_locked() probably should be changed into a lockdep_assert_held() call. Thanks, Bart.