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=-14.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 CDDC9C433DF for ; Wed, 19 Aug 2020 03:08:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A2AFA2078B for ; Wed, 19 Aug 2020 03:08:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ZheUj4oE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727068AbgHSDID (ORCPT ); Tue, 18 Aug 2020 23:08:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57754 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727043AbgHSDIC (ORCPT ); Tue, 18 Aug 2020 23:08:02 -0400 Received: from mail-pj1-x1044.google.com (mail-pj1-x1044.google.com [IPv6:2607:f8b0:4864:20::1044]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A4A68C061389 for ; Tue, 18 Aug 2020 20:08:02 -0700 (PDT) Received: by mail-pj1-x1044.google.com with SMTP id mw10so450098pjb.2 for ; Tue, 18 Aug 2020 20:08:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding:content-language; bh=Sb9vbApk6CCB20Zi+qR+drVkCzG+Jh/5puXQEl4JfcY=; b=ZheUj4oEUa9jkfC7MIzvwyIOt7CSsIju3fxqj61oZ8YurHStdJndVxmOdESqK7s1BF JEL5cm1x0te+6ivDYKWD/0tDxsLPSVuBDxdCE00qYw7rzXHt6eQfTpz294PBLTSUjNok 9JfbOj77KqkTGzS2qSRU/fZ6cA6RvQcRoeWO9PYmZYh1d2Yr57gLX5TmE62yPf0ek6qu XQmyeL8UQRljHMPaLknpiwYQWel7oDmshMkf2unjnsADpzJG+r/MXYT72WEQJIvNKp2D vNR6mnbuR5BFCF17RqYsPcL8KCfY6wyDgoiBOqwU2Qkv2BzDoXlfxmweD+yqTntEXvPb HU7Q== 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-transfer-encoding :content-language; bh=Sb9vbApk6CCB20Zi+qR+drVkCzG+Jh/5puXQEl4JfcY=; b=SnJDO9p6+xAEHM6cpkMNpZXBvf5HSixQg0eUOLLGyiBNwz4tWd3epxCAUXII2QSYUK XTsaxdm1PkzUCAK1zCMCDU1bIelXEpaMWwe5uHF2aFJFFrbP4w6gRU3JGCTT6DgQHYDi nvLGzh42mCbSEHZBU0waYBl8U7bY4d07AoJ39zWYCrcuuXafiUsYFk5vaIIlCq9Bw5er t+HywulEQ8BxxIHH74n+Dh9Ye8kPOlHWQB7qViHxQJMd2+uF5W62BuulKrhP2qXQJ1CA g9hCFa2xcB1WVYPNWdU71UoDM6T22zHKIZp3oC55PZG0FIhDTHA6xgmcnh8OICPMXYdH vntw== X-Gm-Message-State: AOAM531qBQB3MlOuME/OHzvkriIOcnJoyfcgXcjNMNT+YLa/U2mxdhVL JfNs8zdWe2ZZX6dljXwFUzo= X-Google-Smtp-Source: ABdhPJxWv2xGBQICiR/Igmn8a5Aj8C1L5m4cRszsabYpMWNATLEDB/W2lGP6bdaKM8MV6ItbDIv/Kw== X-Received: by 2002:a17:90a:bc96:: with SMTP id x22mr2537807pjr.164.1597806482096; Tue, 18 Aug 2020 20:08:02 -0700 (PDT) Received: from [10.75.201.17] ([118.201.220.138]) by smtp.gmail.com with ESMTPSA id u3sm338206pjn.29.2020.08.18.20.07.59 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 18 Aug 2020 20:08:01 -0700 (PDT) Subject: Re: [PATCH for-rc] RDMA/rxe: Fix panic when calling kmem_cache_create() To: Leon Romanovsky , Kamal Heib Cc: linux-rdma@vger.kernel.org, Doug Ledford , Jason Gunthorpe References: <20200812111447.256822-1-kamalheib1@gmail.com> <9701a68d-c377-474a-5f65-c4e045a67e11@gmail.com> <20200816221236.GA821081@kheib-workstation> <20200818055057.GA881164@kheib-workstation> <20200818074956.GM7555@unreal> From: Zhu Yanjun Message-ID: <31678b13-4db1-d454-a85c-1ba5c8029c41@gmail.com> Date: Wed, 19 Aug 2020 11:07:56 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.1.1 MIME-Version: 1.0 In-Reply-To: <20200818074956.GM7555@unreal> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On 8/18/2020 3:49 PM, Leon Romanovsky wrote: > On Tue, Aug 18, 2020 at 08:50:57AM +0300, Kamal Heib wrote: >> On Tue, Aug 18, 2020 at 09:48:43AM +0800, Zhu Yanjun wrote: >>> On 8/17/2020 6:12 AM, Kamal Heib wrote: >>>> On Sat, Aug 15, 2020 at 02:58:45PM +0800, Zhu Yanjun wrote: >>>>> On 8/12/2020 7:14 PM, Kamal Heib wrote: >>>>>> To avoid the following kernel panic when calling kmem_cache_create() >>>>>> with a NULL pointer from pool_cache(), >>>>> What is the root cause of this kernel panic? >>>>> >>>> The kernel panic is triggered using the following command and it happen >>>> because the cache is not getting initialized. >>>> >>>> modprobe rdma_rxe add=eno1 >>>> >>>> Thanks, >>>> Kamal >>>> >>>>> Zhu Yanjun >>>>> >>>>>> move the rxe_cache_init() to the >>>>>> context of device creation. >>>>>> >>>>>> BUG: unable to handle kernel NULL pointer dereference at 000000000000000b >>>>>> PGD 0 P4D 0 >>>>>> Oops: 0000 [#1] SMP NOPTI >>>>>> CPU: 4 PID: 8512 Comm: modprobe Kdump: loaded Not tainted 4.18.0-231.el8.x86_64 #1 >>>>>> Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 10/02/2018 >>>>>> RIP: 0010:kmem_cache_alloc+0xd1/0x1b0 >>>>>> Code: 8b 57 18 45 8b 77 1c 48 8b 5c 24 30 0f 1f 44 00 00 5b 48 89 e8 5d 41 5c 41 5d 41 5e 41 5f c3 81 e3 00 00 10 00 75 0e 4d 89 fe <41> f6 47 0b 04 0f 84 6c ff ff ff 4c 89 ff e8 cc da 01 00 49 89 c6 >>>>>> RSP: 0018:ffffa2b8c773f9d0 EFLAGS: 00010246 >>>>>> RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000005 >>>>>> RDX: 0000000000000004 RSI: 00000000006080c0 RDI: 0000000000000000 >>>>>> RBP: ffff8ea0a8634fd0 R08: ffffa2b8c773f988 R09: 00000000006000c0 >>>>>> R10: 0000000000000000 R11: 0000000000000230 R12: 00000000006080c0 >>>>>> R13: ffffffffc0a97fc8 R14: 0000000000000000 R15: 0000000000000000 >>>>>> FS: 00007f9138ed9740(0000) GS:ffff8ea4ae800000(0000) knlGS:0000000000000000 >>>>>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >>>>>> CR2: 000000000000000b CR3: 000000046d59a000 CR4: 00000000003406e0 >>>>>> Call Trace: >>>>>> rxe_alloc+0xc8/0x160 [rdma_rxe] >>>>>> rxe_get_dma_mr+0x25/0xb0 [rdma_rxe] >>>>>> __ib_alloc_pd+0xcb/0x160 [ib_core] >>>>>> ib_mad_init_device+0x296/0x8b0 [ib_core] >>>>>> add_client_context+0x11a/0x160 [ib_core] >>>>>> enable_device_and_get+0xdc/0x1d0 [ib_core] >>>>>> ib_register_device+0x572/0x6b0 [ib_core] >>>>>> ? crypto_create_tfm+0x32/0xe0 >>>>>> ? crypto_create_tfm+0x7a/0xe0 >>>>>> ? crypto_alloc_tfm+0x58/0xf0 >>>>>> rxe_register_device+0x19d/0x1c0 [rdma_rxe] >>>>>> rxe_net_add+0x3d/0x70 [rdma_rxe] >>>>>> ? dev_get_by_name_rcu+0x73/0x90 >>>>>> rxe_param_set_add+0xaf/0xc0 [rdma_rxe] >>>>>> parse_args+0x179/0x370 >>>>>> ? ref_module+0x1b0/0x1b0 >>>>>> load_module+0x135e/0x17e0 >>>>>> ? ref_module+0x1b0/0x1b0 >>>>>> ? __do_sys_init_module+0x13b/0x180 >>>>>> __do_sys_init_module+0x13b/0x180 >>>>>> do_syscall_64+0x5b/0x1a0 >>>>>> entry_SYSCALL_64_after_hwframe+0x65/0xca >>>>>> RIP: 0033:0x7f9137ed296e >>>>>> >>>>>> Fixes: 8700e3e7c485 ("Soft RoCE driver") >>>>>> Signed-off-by: Kamal Heib >>>>>> --- >>>>>> drivers/infiniband/sw/rxe/rxe.c | 14 +++++++------- >>>>>> drivers/infiniband/sw/rxe/rxe_pool.c | 3 +++ >>>>>> drivers/infiniband/sw/rxe/rxe_sysfs.c | 7 +++++++ >>>>>> 3 files changed, 17 insertions(+), 7 deletions(-) >>>>>> >>>>>> diff --git a/drivers/infiniband/sw/rxe/rxe.c b/drivers/infiniband/sw/rxe/rxe.c >>>>>> index 5642eefb4ba1..60d5086dd34d 100644 >>>>>> --- a/drivers/infiniband/sw/rxe/rxe.c >>>>>> +++ b/drivers/infiniband/sw/rxe/rxe.c >>>>>> @@ -318,6 +318,13 @@ static int rxe_newlink(const char *ibdev_name, struct net_device *ndev) >>>>>> goto err; >>>>>> } >>>>>> + /* initialize slab caches for managed objects */ >>>>>> + err = rxe_cache_init(); >>>>>> + if (err) { >>>>>> + pr_err("unable to init object pools\n"); >>>>>> + goto err; >>>>>> + } >>>>>> + >>>>>> err = rxe_net_add(ibdev_name, ndev); >>>>>> if (err) { >>>>>> pr_err("failed to add %s\n", ndev->name); >>>>>> @@ -336,13 +343,6 @@ static int __init rxe_module_init(void) >>>>>> { >>>>>> int err; >>>>>> - /* initialize slab caches for managed objects */ >>>>>> - err = rxe_cache_init(); >>> When modprobe rdma_rxe, rxe_module_init should be called. Then >>> rxe_cache_init should be also called. >>> >>> Why does the above call trace occur? >>> >>> Zhu Yanjun >>> >> As you can see in the call trace attached to the commit message, When >> running the "modprobe rdma_rxe add=eno1" command the rxe_param_set_add() >> is called before rxe_module_init() (without init the caches), so the >> call trace occurs when trying to register the allocated rxe device from >> the context of rxe_param_set_add() without initialize the caches. > I would expect the fix being in rxe_init() instead of putting calls to > rxe_cache_init() in all places. I agree with you. Is it possible to make rxe_module_init be called before rxe_param_set_add? Thanks > > Thanks