From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EAAE913AF3 for ; Tue, 14 Nov 2023 08:22:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 28BCE1AC for ; Tue, 14 Nov 2023 00:22:47 -0800 (PST) Received: from dggpeml500026.china.huawei.com (unknown [172.30.72.54]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4STzjW16vKzrVC4; Tue, 14 Nov 2023 16:19:27 +0800 (CST) Received: from [10.174.178.66] (10.174.178.66) by dggpeml500026.china.huawei.com (7.185.36.106) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Tue, 14 Nov 2023 16:22:45 +0800 Message-ID: Date: Tue, 14 Nov 2023 16:22:45 +0800 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.0.2 Subject: Re: [PATCH net-next] bonding: use WARN_ON instead of BUG in alb_upper_dev_walk To: Jay Vosburgh CC: , , , , , , , References: <20231113092754.3285306-1-shaozhengchao@huawei.com> <9928.1699921899@famine> From: shaozhengchao In-Reply-To: <9928.1699921899@famine> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.178.66] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpeml500026.china.huawei.com (7.185.36.106) X-CFilter-Loop: Reflected On 2023/11/14 8:31, Jay Vosburgh wrote: > Zhengchao Shao wrote: > >> If failed to allocate "tags" or could not find the final upper device from >> start_dev's upper list in bond_verify_device_path(), only the loopback >> detection of the current upper device should be affected, and the system is >> no need to be panic. >> >> Signed-off-by: Zhengchao Shao >> --- >> drivers/net/bonding/bond_alb.c | 6 ++++-- >> 1 file changed, 4 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c >> index dc2c7b979656..5519cc95b966 100644 >> --- a/drivers/net/bonding/bond_alb.c >> +++ b/drivers/net/bonding/bond_alb.c >> @@ -984,8 +984,10 @@ static int alb_upper_dev_walk(struct net_device *upper, >> */ >> if (netif_is_macvlan(upper) && !strict_match) { >> tags = bond_verify_device_path(bond->dev, upper, 0); >> - if (IS_ERR_OR_NULL(tags)) >> - BUG(); >> + if (IS_ERR_OR_NULL(tags)) { >> + WARN_ON(1); >> + return 0; > > This seems reasonable enough, although I'd suggest the using > WARN_ON_ONCE instead of WARN_ON. Alternatively, this could stay as > WARN_ON if the above also returns non-zero in order to terminate the > netdev_walk_all_upper_dev_rcu walk. The intent here is to avoid > spamming the log if there's a lot of macvlans above the bond. If the > allocation in bond_verify_device_path failed, trying again immediately > seems likely to fail as well. Hi Jay: Thank you for your reply. I do agree with you. I will send v2. Zhengchao Shao > > We could also arrange for whatever called alb_upper_dev_walk to > reschedule at a slightly later time, but I don't think that's worth the > trouble. The bond will by default resend learning packets once per > second, so issues related to a lost learning packet should resolve > relatively quickly. > > -J > >> + } >> alb_send_lp_vid(slave, upper->dev_addr, >> tags[0].vlan_proto, tags[0].vlan_id); >> kfree(tags); >> -- >> 2.34.1 > > --- > -Jay Vosburgh, jay.vosburgh@canonical.com