From patchwork Tue Jun 8 18:26:02 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 457595 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=-18.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 01FB1C4743F for ; Tue, 8 Jun 2021 19:05:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E2EE360551 for ; Tue, 8 Jun 2021 19:05:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235778AbhFHTHg (ORCPT ); Tue, 8 Jun 2021 15:07:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:40168 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237818AbhFHTFf (ORCPT ); Tue, 8 Jun 2021 15:05:35 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2C9E461876; Tue, 8 Jun 2021 18:46:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1623177980; bh=r+J9dgsr+vI6MXh1oMDKeEKmapaCkU+l1kKOI/xx4GM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NSTX3T6bI6dBTcCHfZF2PaAe5hMe6gEag6MdzwkDiH+wHsV4jZ8zmtRriR14CwKHv 4/sHaz/0TydWZRnb8Mpo3wMOrEPG7LRtdZI6ISBhfz6drRILK/CRUYhNjkT/lDIphT jYi453cMSQEySvZ/tMCdaxA+iotl5VRf+s4Nvfw0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Maxim Mikityanskiy , Tariq Toukan , "David S. Miller" , Sasha Levin Subject: [PATCH 5.12 032/161] net/tls: Replace TLS_RX_SYNC_RUNNING with RCU Date: Tue, 8 Jun 2021 20:26:02 +0200 Message-Id: <20210608175946.538035302@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210608175945.476074951@linuxfoundation.org> References: <20210608175945.476074951@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Maxim Mikityanskiy [ Upstream commit 05fc8b6cbd4f979a6f25759c4a17dd5f657f7ecd ] RCU synchronization is guaranteed to finish in finite time, unlike a busy loop that polls a flag. This patch is a preparation for the bugfix in the next patch, where the same synchronize_net() call will also be used to sync with the TX datapath. Signed-off-by: Maxim Mikityanskiy Reviewed-by: Tariq Toukan Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- include/net/tls.h | 1 - net/tls/tls_device.c | 10 +++------- 2 files changed, 3 insertions(+), 8 deletions(-) diff --git a/include/net/tls.h b/include/net/tls.h index 3eccb525e8f7..6531ace2a68b 100644 --- a/include/net/tls.h +++ b/include/net/tls.h @@ -193,7 +193,6 @@ struct tls_offload_context_tx { (sizeof(struct tls_offload_context_tx) + TLS_DRIVER_STATE_SIZE_TX) enum tls_context_flags { - TLS_RX_SYNC_RUNNING = 0, /* Unlike RX where resync is driven entirely by the core in TX only * the driver knows when things went out of sync, so we need the flag * to be atomic. diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c index d9cd229aa111..2602d61a8d28 100644 --- a/net/tls/tls_device.c +++ b/net/tls/tls_device.c @@ -680,15 +680,13 @@ static void tls_device_resync_rx(struct tls_context *tls_ctx, struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); struct net_device *netdev; - if (WARN_ON(test_and_set_bit(TLS_RX_SYNC_RUNNING, &tls_ctx->flags))) - return; - trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type); + rcu_read_lock(); netdev = READ_ONCE(tls_ctx->netdev); if (netdev) netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn, TLS_OFFLOAD_CTX_DIR_RX); - clear_bit_unlock(TLS_RX_SYNC_RUNNING, &tls_ctx->flags); + rcu_read_unlock(); TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC); } @@ -1300,9 +1298,7 @@ static int tls_device_down(struct net_device *netdev) netdev->tlsdev_ops->tls_dev_del(netdev, ctx, TLS_OFFLOAD_CTX_DIR_RX); WRITE_ONCE(ctx->netdev, NULL); - smp_mb__before_atomic(); /* pairs with test_and_set_bit() */ - while (test_bit(TLS_RX_SYNC_RUNNING, &ctx->flags)) - usleep_range(10, 200); + synchronize_net(); dev_put(netdev); list_del_init(&ctx->list);