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=-6.1 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 65AD5C32788 for ; Thu, 11 Oct 2018 15:47:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 12BE42085B for ; Thu, 11 Oct 2018 15:47:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="NlI12OVs" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 12BE42085B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731729AbeJKXOt (ORCPT ); Thu, 11 Oct 2018 19:14:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:47992 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726882AbeJKXOs (ORCPT ); Thu, 11 Oct 2018 19:14:48 -0400 Received: from localhost (ip-213-127-77-176.ip.prioritytelecom.net [213.127.77.176]) (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 966FB2085B; Thu, 11 Oct 2018 15:47:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539272822; bh=YKE3ndWD+/NR6DZ5COMLmOeKWaRaPu2F/BToDswREfw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NlI12OVsWvg6lpm4XT4k5N2Er99H/1WNE0H5pXaT1Fs02lBdLrHSEHTlHTQW7a7/B p5VZ7CLNv6eKRmE176HqK2TpvGZeX+xmyF2WcjE0ME7ZAKHCiRw9mYmwkE851ecyjx LVUny1uHO9b7hMEnm6rZT4xUnWaGwfDKO7ShPMQI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Michael S. Tsirkin" , Tetsuo Handa , Michal Hocko , Wei Wang , Jan Stancek , Sudip Mukherjee Subject: [PATCH 4.14 44/45] virtio_balloon: fix increment of vb->num_pfns in fill_balloon() Date: Thu, 11 Oct 2018 17:40:11 +0200 Message-Id: <20181011152510.855514157@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181011152508.885515042@linuxfoundation.org> References: <20181011152508.885515042@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review 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 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jan Stancek commit d9e427f6ab8142d6868eb719e6a7851aafea56b6 upstream. commit c7cdff0e8647 ("virtio_balloon: fix deadlock on OOM") changed code to increment vb->num_pfns before call to set_page_pfns(), which used to happen only after. This patch fixes boot hang for me on ppc64le KVM guests. Fixes: c7cdff0e8647 ("virtio_balloon: fix deadlock on OOM") Cc: Michael S. Tsirkin Cc: Tetsuo Handa Cc: Michal Hocko Cc: Wei Wang Cc: stable@vger.kernel.org Signed-off-by: Jan Stancek Signed-off-by: Michael S. Tsirkin Signed-off-by: Sudip Mukherjee Signed-off-by: Greg Kroah-Hartman --- drivers/virtio/virtio_balloon.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -174,13 +174,12 @@ static unsigned fill_balloon(struct virt while ((page = balloon_page_pop(&pages))) { balloon_page_enqueue(&vb->vb_dev_info, page); - vb->num_pfns += VIRTIO_BALLOON_PAGES_PER_PAGE; - set_page_pfns(vb, vb->pfns + vb->num_pfns, page); vb->num_pages += VIRTIO_BALLOON_PAGES_PER_PAGE; if (!virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_DEFLATE_ON_OOM)) adjust_managed_page_count(page, -1); + vb->num_pfns += VIRTIO_BALLOON_PAGES_PER_PAGE; } num_allocated_pages = vb->num_pfns;