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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 AD685C169C4 for ; Tue, 29 Jan 2019 11:37:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7358120882 for ; Tue, 29 Jan 2019 11:37:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548761857; bh=J3V2ge1SNFkjfFf833kFJLmhxbs3UgTytFlBLSRaLuc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Ag3uECfqJ4wAYHKMkwm2Hb7QYY5Px8vkc70w/+LIF0lXigrQIKBe/RlNdAxfNEWNy KBKy9Kz0rcm88vUYFx7OYK5OGlgWrXnrzsp1ggjhH/ZOx9tPMzKJmvzT+S+tcQLVBu PtWXwMNcEFxOBlYnMAbrigl9WOGnfFP3FzxEiv2Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728879AbfA2Lhg (ORCPT ); Tue, 29 Jan 2019 06:37:36 -0500 Received: from mail.kernel.org ([198.145.29.99]:54222 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727728AbfA2Lhf (ORCPT ); Tue, 29 Jan 2019 06:37:35 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B86F020882; Tue, 29 Jan 2019 11:37:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548761854; bh=J3V2ge1SNFkjfFf833kFJLmhxbs3UgTytFlBLSRaLuc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SQ/R3K8mTo7qzpeYZSpAx4Uaewcbgd/eq4AyEQb19v3beKkGzreb8xTicygVj1YVf Sn8kZQ0QgjV/q9h5cGOzvTqXOZJqNnKDIStbbUj7ZlWBqW7489Z2N5ajLQdVdyxz2k q6YU5zZh/EAz6gGZKAsYHtcvHqG/A2BDa8+IuJJI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chuck Lever , Anna Schumaker , Sasha Levin Subject: [PATCH 4.20 023/117] SUNRPC: Address Kerberos performance/behavior regression Date: Tue, 29 Jan 2019 12:34:34 +0100 Message-Id: <20190129113208.820427598@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190129113207.477505932@linuxfoundation.org> References: <20190129113207.477505932@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit deaa5c96c2f7e8b934088a1e70a0fe8797bd1149 ] When using Kerberos with v4.20, I've observed frequent connection loss on heavy workloads. I traced it down to the client underrunning the GSS sequence number window -- NFS servers are required to drop the RPC with the low sequence number, and also drop the connection to signal that an RPC was dropped. Bisected to commit 918f3c1fe83c ("SUNRPC: Improve latency for interactive tasks"). I've got a one-line workaround for this issue, which is easy to backport to v4.20 while a more permanent solution is being derived. Essentially, tk_owner-based sorting is disabled for RPCs that carry a GSS sequence number. Fixes: 918f3c1fe83c ("SUNRPC: Improve latency for interactive ... ") Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/sunrpc/xprt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -1177,7 +1177,7 @@ xprt_request_enqueue_transmit(struct rpc INIT_LIST_HEAD(&req->rq_xmit2); goto out; } - } else { + } else if (!req->rq_seqno) { list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) { if (pos->rq_task->tk_owner != task->tk_owner) continue;