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=-19.0 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, USER_AGENT_GIT autolearn=unavailable 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 1F0BDC433E9 for ; Mon, 15 Mar 2021 14:33:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DEBAE64E77 for ; Mon, 15 Mar 2021 14:33:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235489AbhCOOby (ORCPT ); Mon, 15 Mar 2021 10:31:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:37632 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229743AbhCOOBL (ORCPT ); Mon, 15 Mar 2021 10:01:11 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 906E164F0C; Mon, 15 Mar 2021 14:00:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1615816838; bh=fg8Q1EYWAk3JgG7ZOKsNwOrprZ0nqJY0OgF5mVDigTA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IfD6YL/Xdyo/HbNZyZ9gp0v6RPetwkqDH3FDB5OI1LIOvjxY3u7zRQ1sotEK+ZSEu oYCJF6bdIBVxPc79mkXI/cafNDLnujavBzSXpPW1NGDiiqqwMzZckBJF58yipDpo0K vnAAgXiaT3i25edOnfHYrdiiYrUmq8gJWGY7qrTo= From: gregkh@linuxfoundation.org To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Benjamin Coddington , Anna Schumaker , Sasha Levin Subject: [PATCH 5.4 145/168] SUNRPC: Set memalloc_nofs_save() for sync tasks Date: Mon, 15 Mar 2021 14:56:17 +0100 Message-Id: <20210315135555.106561418@linuxfoundation.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210315135550.333963635@linuxfoundation.org> References: <20210315135550.333963635@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Greg Kroah-Hartman From: Benjamin Coddington [ Upstream commit f0940f4b3284a00f38a5d42e6067c2aaa20e1f2e ] We could recurse into NFS doing memory reclaim while sending a sync task, which might result in a deadlock. Set memalloc_nofs_save for sync task execution. Fixes: a1231fda7e94 ("SUNRPC: Set memalloc_nofs_save() on all rpciod/xprtiod jobs") Signed-off-by: Benjamin Coddington Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin --- net/sunrpc/sched.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c index 7afbf15bcbd9..4beb6d2957c3 100644 --- a/net/sunrpc/sched.c +++ b/net/sunrpc/sched.c @@ -990,8 +990,11 @@ void rpc_execute(struct rpc_task *task) rpc_set_active(task); rpc_make_runnable(rpciod_workqueue, task); - if (!is_async) + if (!is_async) { + unsigned int pflags = memalloc_nofs_save(); __rpc_execute(task); + memalloc_nofs_restore(pflags); + } } static void rpc_async_schedule(struct work_struct *work) -- 2.30.1