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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4FC67C4332F for ; Sun, 6 Nov 2022 19:14:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229955AbiKFTO5 (ORCPT ); Sun, 6 Nov 2022 14:14:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36690 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229919AbiKFTO4 (ORCPT ); Sun, 6 Nov 2022 14:14:56 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F0009B866 for ; Sun, 6 Nov 2022 11:14:55 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8BDC160D24 for ; Sun, 6 Nov 2022 19:14:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6195DC433D6; Sun, 6 Nov 2022 19:14:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1667762095; bh=ZOdNk6qtyfdbx8g/LSFBhMuCcRoHrvydNvhbi0HQhaI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=mGrtrB4IxYyjsuL2pyVFSw8Vvd91xXPcMBdgVgqfv8yp5xUT1gk9o+DUkjBPqM9ir 2wd+mTgRxzSg/wG8vPnYbS2qg0rt3quIAtomUzSlYSxnucZnWEDHUi3kHILx4NBULZ QdkF97wdNY8mPETHAFJI2+qYWRKW/wtWD+hGu3/3ffMc66J1VW5CiJpVEzmGSgot5l nnzhznb1CyKNSwPHYN9AgAA5NeYs5yMF+SdadBQ6QL9wpxWye8I0gnFNxK0RAJo0G9 Y9bhetuZaRdIC7aG4BeKNXJptqnxBCeZraxilV8Rv5zjv2r7utR/7JhtxJVhws2Q3X KNsujmShwO6gw== Date: Sun, 6 Nov 2022 21:14:50 +0200 From: Leon Romanovsky To: Stefan Assmann Cc: intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org, anthony.l.nguyen@intel.com, patryk.piotrowski@intel.com Subject: Re: [PATCH net-next] iavf: check that state transitions happen under lock Message-ID: References: <20221028134515.253022-1-sassmann@kpanic.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221028134515.253022-1-sassmann@kpanic.de> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Fri, Oct 28, 2022 at 03:45:15PM +0200, Stefan Assmann wrote: > Add a check to make sure crit_lock is being held during every state > transition and print a warning if that's not the case. For convenience > a wrapper is added that helps pointing out where the locking is missing. > > Make an exception for iavf_probe() as that is too early in the init > process and generates a false positive report. > > Signed-off-by: Stefan Assmann > --- > drivers/net/ethernet/intel/iavf/iavf.h | 23 +++++++++++++++------ > drivers/net/ethernet/intel/iavf/iavf_main.c | 2 +- > 2 files changed, 18 insertions(+), 7 deletions(-) > > diff --git a/drivers/net/ethernet/intel/iavf/iavf.h b/drivers/net/ethernet/intel/iavf/iavf.h > index 3f6187c16424..28f41bbc9c86 100644 > --- a/drivers/net/ethernet/intel/iavf/iavf.h > +++ b/drivers/net/ethernet/intel/iavf/iavf.h > @@ -498,19 +498,30 @@ static inline const char *iavf_state_str(enum iavf_state_t state) > } > } > > -static inline void iavf_change_state(struct iavf_adapter *adapter, > - enum iavf_state_t state) > +static inline void __iavf_change_state(struct iavf_adapter *adapter, > + enum iavf_state_t state, > + const char *func, > + int line) > { > if (adapter->state != state) { > adapter->last_state = adapter->state; > adapter->state = state; > } > - dev_dbg(&adapter->pdev->dev, > - "state transition from:%s to:%s\n", > - iavf_state_str(adapter->last_state), > - iavf_state_str(adapter->state)); > + if (mutex_is_locked(&adapter->crit_lock)) Please use lockdep for that, and not reinvent it. In you case lockdep_assert_held(&adapter->crit_lock). In addition, mutex_is_locked() doesn't check that this specific function is locked. It checks that this lock is used now. > + dev_dbg(&adapter->pdev->dev, "%s:%d state transition %s to %s\n", > + func, line, > + iavf_state_str(adapter->last_state), > + iavf_state_str(adapter->state)); > + else > + dev_warn(&adapter->pdev->dev, "%s:%d state transition %s to %s without locking!\n", > + func, line, > + iavf_state_str(adapter->last_state), > + iavf_state_str(adapter->state)); > } > > +#define iavf_change_state(adapter, state) \ > + __iavf_change_state(adapter, state, __func__, __LINE__) > + > int iavf_up(struct iavf_adapter *adapter); > void iavf_down(struct iavf_adapter *adapter); > int iavf_process_config(struct iavf_adapter *adapter); > diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c > index 3fc572341781..bbc0c9f347a7 100644 > --- a/drivers/net/ethernet/intel/iavf/iavf_main.c > +++ b/drivers/net/ethernet/intel/iavf/iavf_main.c > @@ -4892,7 +4892,7 @@ static int iavf_probe(struct pci_dev *pdev, const struct pci_device_id *ent) > hw->back = adapter; > > adapter->msg_enable = BIT(DEFAULT_DEBUG_LEVEL_SHIFT) - 1; > - iavf_change_state(adapter, __IAVF_STARTUP); > + adapter->state = __IAVF_STARTUP; > > /* Call save state here because it relies on the adapter struct. */ > pci_save_state(pdev); > -- > 2.37.3 >