From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=115.124.30.100 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794459290; b=4iNhu42vX0R+msbksGQWM0qmDU1gaA/8tO46AICAc4mqlXKwYRm12SBBCFdW3Ydrtl28 JEUlRqcB/GkJ3BN74utxjOqZTxb9+aj9JIpHHrHWpwsAOJnndkkwWTCXFGyvJFffIeehI gekOauXfJ7zV3Z7VRRzhwwXrmwGa+1mwHo8AQdBd7sZVZSyCHUMNB1AdNFxs484YlqpAH qSDMMCD8A9dEY++iZkHqEnlTQi8MEDTaGrkp5EBCBhG3+q7K/hFgiOUd66lTHaUV7MAVH 6PAR1ZMA3+5sqO6cFOH+y5v0sLpZvZ0JUnE0G0yMOWQquCF+/8QXHU2pFu6w0slo6rQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794459290; h=DMARC-Filter:DKIM-Signature:X-Alimail-AntiSpam:Received:Date:From:To: Cc:Subject:Message-ID:Reply-To:References:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; bh=/V28rCHXi3T9oO9LFCn5sfVOcz0zmvubCJbcVebXDxQ=; b=xEHiGJOb9wMcknM/xQqVA+uG6A8Dw1YzVX26qlYAbMjn4oioog3Mr3AAKT08BzbQoPlm e4OxRa1wKaPDLNWamivJj3958wPNvpfHxAP5PxeVSkECNXrHj2oaV/4/lAcCdMRexkeTL X0FThaqeWpQgmrzDoL3pFzhKNHmoVMUP5vmAd9pZxc8sa/B+aEOPL4ZrFGXYGhwHmntJs X5hn1wYLE0pkULJeQ3gbW4FqosCURDlMCm0jKcWUUhUDbJTt+ULk7cXmLAc7lHINhDuGf f8vZSxmm4Eiwpdkimfi00q9bVb/kT200z+62eU59VqS4jJXdgCjPqorqoo3DXRn/iZw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass header.d=linux.alibaba.com header.i=@linux.alibaba.com header.a=rsa-sha256 header.s=default header.b=MXltY6b0; arc=none smtp.remote-ip=115.124.30.100 Received: from out30-100.freemail.mail.aliyun.com (out30-100.freemail.mail.aliyun.com [115.124.30.100]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9FBCB606A32A; Thu, 12 Nov 2026 04:54:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 9FBCB606A32A Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.a=rsa-sha256 header.s=default header.b=MXltY6b0 DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1794459284; h=Date:From:To:Subject:Message-ID:MIME-Version:Content-Type; bh=/V28rCHXi3T9oO9LFCn5sfVOcz0zmvubCJbcVebXDxQ=; b=MXltY6b02zxJBPSSJCcrFOFIVlsBPwa+MF+BOn7nVcYMoHG/lR/idyOofAtP+7o28bmnleqYQobOuF1X03XhPFzpBC/hqZgH8dTQlrXbc1lMAFQJxWEzyBHEg4X9w+v0wAMn3OjhU+vlgQS7hHIJLJYkmTvC3eWmg5pBomYYpaY= X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R151e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam011083073210;MF=dust.li@linux.alibaba.com;NM=1;PH=DS;RN=37;SR=0;TI=SMTPD_---0XEaoXEq_1794459281; Received: from localhost(mailfrom:dust.li@linux.alibaba.com fp:SMTPD_---0XEaoXEq_1794459281 cluster:ay36) by smtp.aliyun-inc.com; Thu, 12 Nov 2026 12:54:41 +0800 Date: Thu, 12 Nov 2026 12:54:41 +0800 From: Dust Li To: Jiayuan Chen , netdev@vger.kernel.org Cc: David Ahern , Ido Schimmel , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Pablo Neira Ayuso , Florian Westphal , Phil Sutter , Nikolay Aleksandrov , Paul Moore , Matthieu Baerts , Mat Martineau , Geliang Tang , Julian Anastasov , Allison Henderson , Marcelo Ricardo Leitner , Xin Long , "D. Wythe" , Sidraya Jayagond , Mahanta Jambigi , Tony Lu , Wen Gu , linux-kernel@vger.kernel.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, bridge@lists.linux.dev, linux-security-module@vger.kernel.org, mptcp@lists.linux.dev, lvs-devel@vger.kernel.org, linux-rdma@vger.kernel.org, rds-devel@oss.oracle.com, linux-sctp@vger.kernel.org, linux-s390@vger.kernel.org Subject: Re: [PATCH net-next 12/14] net/smc: annotate data-races around smc sysctls Message-ID: Reply-To: dust.li@linux.alibaba.com References: <20261109025425.328445-1-jiayuan.chen@linux.dev> <20261109025425.328445-13-jiayuan.chen@linux.dev> X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261109025425.328445-13-jiayuan.chen@linux.dev> On 2026-11-09 10:52:11, Jiayuan Chen wrote: >autocorking_size, smcr_buf_type, smcr_max_links_per_lgr, >smcr_max_conns_per_lgr and limit_smc_hs are read without any lock while >their sysctl handlers update them with WRITE_ONCE(), and the SMC netlink >handlers toggle limit_smc_hs with plain writes. Add READ_ONCE() to the >readers and WRITE_ONCE() to those handlers. > >Signed-off-by: Jiayuan Chen Acked-by: Dust Li Best regards, Dust >--- > net/smc/af_smc.c | 8 ++++---- > net/smc/smc_clc.c | 8 ++++---- > net/smc/smc_core.c | 2 +- > net/smc/smc_tx.c | 2 +- > 4 files changed, 10 insertions(+), 10 deletions(-) > >diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c >index d10244af5bd29..9a657172be8f9 100644 >--- a/net/smc/af_smc.c >+++ b/net/smc/af_smc.c >@@ -88,7 +88,7 @@ int smc_nl_dump_hs_limitation(struct sk_buff *skb, struct netlink_callback *cb) > return -ENOMEM; > > if (nla_put_u8(skb, SMC_NLA_HS_LIMITATION_ENABLED, >- sock_net(skb->sk)->smc.limit_smc_hs)) >+ READ_ONCE(sock_net(skb->sk)->smc.limit_smc_hs))) > goto err; > > genlmsg_end(skb, hdr); >@@ -102,13 +102,13 @@ int smc_nl_dump_hs_limitation(struct sk_buff *skb, struct netlink_callback *cb) > > int smc_nl_enable_hs_limitation(struct sk_buff *skb, struct genl_info *info) > { >- sock_net(skb->sk)->smc.limit_smc_hs = true; >+ WRITE_ONCE(sock_net(skb->sk)->smc.limit_smc_hs, true); > return 0; > } > > int smc_nl_disable_hs_limitation(struct sk_buff *skb, struct genl_info *info) > { >- sock_net(skb->sk)->smc.limit_smc_hs = false; >+ WRITE_ONCE(sock_net(skb->sk)->smc.limit_smc_hs, false); > return 0; > } > >@@ -411,7 +411,7 @@ void smc_sk_init(struct net *net, struct sock *sk, int protocol) > spin_lock_init(&smc->conn.send_lock); > mutex_init(&smc->clcsock_release_lock); > smc_init_saved_callbacks(smc); >- smc->limit_smc_hs = net->smc.limit_smc_hs; >+ smc->limit_smc_hs = READ_ONCE(net->smc.limit_smc_hs); > smc->use_fallback = false; /* assume rdma capability first */ > smc->fallback_rsn = 0; > smc_close_init(smc); >diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c >index 014d527d5462d..df0afeef67cbd 100644 >--- a/net/smc/smc_clc.c >+++ b/net/smc/smc_clc.c >@@ -990,8 +990,8 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini) > } > if (smcr_indicated(ini->smc_type_v2)) { > memcpy(v2_ext->roce, ini->smcrv2.ib_gid_v2, SMC_GID_SIZE); >- v2_ext->max_conns = net->smc.sysctl_max_conns_per_lgr; >- v2_ext->max_links = net->smc.sysctl_max_links_per_lgr; >+ v2_ext->max_conns = READ_ONCE(net->smc.sysctl_max_conns_per_lgr); >+ v2_ext->max_links = READ_ONCE(net->smc.sysctl_max_links_per_lgr); > } > > pclc_base->hdr.length = htons(plen); >@@ -1272,12 +1272,12 @@ int smc_clc_srv_v2x_features_validate(struct smc_sock *smc, > > if (ini->smcr_version & SMC_V2) { > ini->max_conns = min_t(u8, pclc_v2_ext->max_conns, >- net->smc.sysctl_max_conns_per_lgr); >+ READ_ONCE(net->smc.sysctl_max_conns_per_lgr)); > if (ini->max_conns < SMC_CONN_PER_LGR_MIN) > return SMC_CLC_DECL_MAXCONNERR; > > ini->max_links = min_t(u8, pclc_v2_ext->max_links, >- net->smc.sysctl_max_links_per_lgr); >+ READ_ONCE(net->smc.sysctl_max_links_per_lgr)); > if (ini->max_links < SMC_LINKS_ADD_LNK_MIN) > return SMC_CLC_DECL_MAXLINKERR; > } >diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c >index 6021322253e93..3d338019a1b8b 100644 >--- a/net/smc/smc_core.c >+++ b/net/smc/smc_core.c >@@ -990,7 +990,7 @@ static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini) > lgr->net = smc_ib_net(lnk->smcibdev); > lgr_list = &smc_lgr_list.list; > lgr_lock = &smc_lgr_list.lock; >- lgr->buf_type = lgr->net->smc.sysctl_smcr_buf_type; >+ lgr->buf_type = READ_ONCE(lgr->net->smc.sysctl_smcr_buf_type); > atomic_inc(&lgr_cnt); > } > smc->conn.lgr = lgr; >diff --git a/net/smc/smc_tx.c b/net/smc/smc_tx.c >index 0f0c6df3bf2ce..30bffe79d06a3 100644 >--- a/net/smc/smc_tx.c >+++ b/net/smc/smc_tx.c >@@ -148,7 +148,7 @@ static bool smc_should_autocork(struct smc_sock *smc) > int corking_size; > > corking_size = min_t(unsigned int, conn->sndbuf_desc->len >> 1, >- sock_net(&smc->sk)->smc.sysctl_autocorking_size); >+ READ_ONCE(sock_net(&smc->sk)->smc.sysctl_autocorking_size)); > > if (atomic_read(&conn->cdc_pend_tx_wr) == 0 || > smc_tx_prepared_sends(conn) > corking_size) >-- >2.43.0