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 018CEC38A2D for ; Mon, 24 Oct 2022 16:26:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232361AbiJXQ0A (ORCPT ); Mon, 24 Oct 2022 12:26:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54404 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232144AbiJXQZV (ORCPT ); Mon, 24 Oct 2022 12:25:21 -0400 Received: from mail-oa1-x2a.google.com (mail-oa1-x2a.google.com [IPv6:2001:4860:4864:20::2a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 183417295B; Mon, 24 Oct 2022 08:11:45 -0700 (PDT) Received: by mail-oa1-x2a.google.com with SMTP id 586e51a60fabf-13b103a3e5dso12207702fac.2; Mon, 24 Oct 2022 08:11:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=U+Yuvpt1GSZqGdrT4ZNMksu/TT2o+vLhvUeXJWl+juA=; b=G3hjXjpuTgIb1v0BBsl9aKj1EeJjNNdnxPSboKpkfA2YaDukveKgRQdCoDEpf0GYZi uEBqCEoDdFXNFRwdPo/nxG/fxBaDRGUIGi6hSsN+WwMCoB45wT5VVuSfG/PROayYWmar OLJqwR8SDBiTYgxsfuzaPIreO7LOXSSdqkmF1dWM2+0eJrALq6ZmxpUTPJMUPFpBks2P 7RoV7oDfDNGsHRzCTR0xTQd/OyUKY+L3eoWjo697xELzT3PdFI2XpaglgiWlfOwGvEh1 TyLvXFLu4r07xyGrNxgrY6FUzgEU11lz9nGGDDAO671FPgmJOTlfCVO/5LQi1VlFxPCX okIQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=U+Yuvpt1GSZqGdrT4ZNMksu/TT2o+vLhvUeXJWl+juA=; b=56rM6zyUcOahViMCT9WnS1P0EKCuOZUGdt9xnPXh3LcKB1ldTMvGHC5YcVhO0s6th+ FBQ0ZN5jB8ZsNb+jMPmdH6M9+KMHEMk1qvOqwxOXKL1DVcaBqyXd+IQkQyQOiESeAx+2 ZcuqhsAlX1rkCo/AlwAmP/XE5Y1/hVexNchUpjzAiE9Twz7V1aZsg/KRemZXD9RJrjIq nB1qI8FlVlmDtUmCtvuWzgrOlNC9k7nvy0SquOxChyp0YGZeBux8o14XThmohJ0ZWPxL KIlWVHgKwUAxE3FpxFMYeeUaSBw3PSboeOdhNddotZw//us8MLeUti3n62Npnnaf5vqi MR8g== X-Gm-Message-State: ACrzQf2ZdsJCfowBPuTPM+RTvcrI2vrYrT18kVARR+RP/jI06ZtxZ3Zj P/hW5bMvgYO2B+zOJL9RT02XbUYQMDo= X-Google-Smtp-Source: AMsMyM5UPuATp0U6GswxRNGFVsyX6hVuubEeKJjtgK1rqAC7YNJAZLcqV4sonzcmR32W9vmIqZ9vmA== X-Received: by 2002:a54:4001:0:b0:355:385e:c07b with SMTP id x1-20020a544001000000b00355385ec07bmr20006904oie.36.1666620617164; Mon, 24 Oct 2022 07:10:17 -0700 (PDT) Received: from ?IPV6:2603:8081:140c:1a00:1e0:e60:c33:b344? (2603-8081-140c-1a00-01e0-0e60-0c33-b344.res6.spectrum.com. [2603:8081:140c:1a00:1e0:e60:c33:b344]) by smtp.gmail.com with ESMTPSA id a5-20020a05680802c500b0034fd36e95bfsm3960219oid.31.2022.10.24.07.10.16 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 24 Oct 2022 07:10:16 -0700 (PDT) Message-ID: Date: Mon, 24 Oct 2022 09:10:15 -0500 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.2.2 Subject: Re: [PATCH for-next v3 1/2] RDMA/rxe: Remove unnecessary mr testing Content-Language: en-US To: Li Zhijian , zyjzyj2000@gmail.com, jgg@ziepe.ca, leon@kernel.org, linux-rdma@vger.kernel.org Cc: linux-kernel@vger.kernel.org References: <1666582315-2-1-git-send-email-lizhijian@fujitsu.com> From: Bob Pearson In-Reply-To: <1666582315-2-1-git-send-email-lizhijian@fujitsu.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/23/22 22:31, Li Zhijian wrote: > Before the testing, we already passed it to rxe_mr_copy() where mr could > be dereferenced. so this checking is not needed. > > The only way that mr is NULL is when it reaches below line 780 with > 'qp->resp.mr = NULL', which is not possible in Bob's explanation[1]. > > 778 if (res->state == rdatm_res_state_new) { > 779 if (!res->replay) { > 780 mr = qp->resp.mr; > 781 qp->resp.mr = NULL; > 782 } else { > > [1] https://lore.kernel.org/lkml/30ff25c4-ce66-eac4-eaa2-64c0db203a19@gmail.com/ > > CC: Bob Pearson > Signed-off-by: Li Zhijian > --- > V3: remove WARN_ON # Yanjun and Bob > --- > drivers/infiniband/sw/rxe/rxe_resp.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c b/drivers/infiniband/sw/rxe/rxe_resp.c > index ed5a09e86417..b02639cf8cba 100644 > --- a/drivers/infiniband/sw/rxe/rxe_resp.c > +++ b/drivers/infiniband/sw/rxe/rxe_resp.c > @@ -811,8 +811,7 @@ static enum resp_states read_reply(struct rxe_qp *qp, > > rxe_mr_copy(mr, res->read.va, payload_addr(&ack_pkt), > payload, RXE_FROM_MR_OBJ); > - if (mr) > - rxe_put(mr); > + rxe_put(mr); > > if (bth_pad(&ack_pkt)) { > u8 *pad = payload_addr(&ack_pkt) + payload; Reviewed-by: Bob Pearson