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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 00CFBC433DB for ; Tue, 16 Feb 2021 07:51:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A0A1464DC3 for ; Tue, 16 Feb 2021 07:51:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229873AbhBPHvA (ORCPT ); Tue, 16 Feb 2021 02:51:00 -0500 Received: from mail.kernel.org ([198.145.29.99]:34824 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229864AbhBPHu7 (ORCPT ); Tue, 16 Feb 2021 02:50:59 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id A516364DDA; Tue, 16 Feb 2021 07:50:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1613461818; bh=oLbYVR/7uQ2FOqhX3AoEMOEOlOVnZwG5sLX6yhmxPfA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Mt46m9zbQRwk5sHbbvHEkvhqjFSbNAx28VnsOSH+sockMI/Izt2nmd0WFBhxjLMsw F+s2nGbnxWPr3X31B0X2tUWBNzViHG4DIQXvM/3yBenBIr8M2/gB0wJGaDlomeX3sz TrrCPyXqBSA/Bfi/OVOL17Ps+zOOcBk/HXftzQHhC251SlNijZouQdUoH1By4eQ/uD 0uRp7kUOa23vR5XuBMo7tS6BN8iPik52hArVz2vq6jV9Ildwdco/BrQKkf6QhxNLsE FDa+C2aC7KoD/jWqQ2NDSSBfQZjsFFuY3UTzvzB3QB0AQNigvOomQz4AXEaUcPIYSD U9lEfyMzkexxg== Date: Tue, 16 Feb 2021 09:50:14 +0200 From: Leon Romanovsky To: Jack Wang Cc: linux-rdma@vger.kernel.org, bvanassche@acm.org, dledford@redhat.com, jgg@ziepe.ca, danil.kipnis@cloud.ionos.com, kernel test robot , Dan Carpenter Subject: Re: [PATCH] RDMA/rtrs-srv: suppress warnings passing zero to 'PTR_ERR' Message-ID: References: <20210216073958.13957-1-jinpu.wang@cloud.ionos.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210216073958.13957-1-jinpu.wang@cloud.ionos.com> Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Tue, Feb 16, 2021 at 08:39:58AM +0100, Jack Wang wrote: > smatch warnings: > drivers/infiniband/ulp/rtrs/rtrs-srv.c:1805 rtrs_rdma_connect() warn: passing zero to 'PTR_ERR' > > Smatch seems confused by the refcount_read condition, so just > treat it seperately. > > Fixes: f0751419d3a1 ("RDMA/rtrs: Only allow addition of path to an already established session") > Reported-by: kernel test robot > Reported-by: Dan Carpenter > Signed-off-by: Jack Wang > --- > drivers/infiniband/ulp/rtrs/rtrs-srv.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/infiniband/ulp/rtrs/rtrs-srv.c b/drivers/infiniband/ulp/rtrs/rtrs-srv.c > index eb17c3a08810..2f6d665bea90 100644 > --- a/drivers/infiniband/ulp/rtrs/rtrs-srv.c > +++ b/drivers/infiniband/ulp/rtrs/rtrs-srv.c > @@ -1799,12 +1799,16 @@ static int rtrs_rdma_connect(struct rdma_cm_id *cm_id, > } > recon_cnt = le16_to_cpu(msg->recon_cnt); > srv = get_or_create_srv(ctx, &msg->paths_uuid, msg->first_conn); > + if (IS_ERR(srv)) { > + err = PTR_ERR(srv); > + goto reject_w_err; > + } > /* > * "refcount == 0" happens if a previous thread calls get_or_create_srv > * allocate srv, but chunks of srv are not allocated yet. > */ > - if (IS_ERR(srv) || refcount_read(&srv->refcount) == 0) { > - err = PTR_ERR(srv); > + if (refcount_read(&srv->refcount) == 0) { I would say that "list_add(&srv->ctx_list, &ctx->srv_list);" line in the get_or_create_srv() is performed too early, relying on zero in the refcount doesn't look great. Thanks