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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 189FFC7618B for ; Thu, 25 Jul 2019 15:21:57 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E50FE2238C for ; Thu, 25 Jul 2019 15:21:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E50FE2238C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:32780 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hqfZ6-0002t4-7q for qemu-devel@archiver.kernel.org; Thu, 25 Jul 2019 11:21:56 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:46663) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hqfYp-0001v8-GQ for qemu-devel@nongnu.org; Thu, 25 Jul 2019 11:21:40 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hqfYo-0003Hu-1S for qemu-devel@nongnu.org; Thu, 25 Jul 2019 11:21:39 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33644) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hqfYn-0003FZ-PV; Thu, 25 Jul 2019 11:21:37 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 19FD885545; Thu, 25 Jul 2019 15:21:36 +0000 (UTC) Received: from [10.36.117.70] (ovpn-117-70.ams2.redhat.com [10.36.117.70]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8FBD260619; Thu, 25 Jul 2019 15:21:31 +0000 (UTC) To: "Michael S. Tsirkin" , qemu-devel@nongnu.org References: <20190725151735.29334-1-mst@redhat.com> From: David Hildenbrand Openpgp: preference=signencrypt Autocrypt: addr=david@redhat.com; prefer-encrypt=mutual; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwX4EEwECACgFAljj9eoCGwMFCQlmAYAGCwkI BwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJEE3eEPcA/4Na5IIP/3T/FIQMxIfNzZshIq687qgG 8UbspuE/YSUDdv7r5szYTK6KPTlqN8NAcSfheywbuYD9A4ZeSBWD3/NAVUdrCaRP2IvFyELj xoMvfJccbq45BxzgEspg/bVahNbyuBpLBVjVWwRtFCUEXkyazksSv8pdTMAs9IucChvFmmq3 jJ2vlaz9lYt/lxN246fIVceckPMiUveimngvXZw21VOAhfQ+/sofXF8JCFv2mFcBDoa7eYob s0FLpmqFaeNRHAlzMWgSsP80qx5nWWEvRLdKWi533N2vC/EyunN3HcBwVrXH4hxRBMco3jvM m8VKLKao9wKj82qSivUnkPIwsAGNPdFoPbgghCQiBjBe6A75Z2xHFrzo7t1jg7nQfIyNC7ez MZBJ59sqA9EDMEJPlLNIeJmqslXPjmMFnE7Mby/+335WJYDulsRybN+W5rLT5aMvhC6x6POK z55fMNKrMASCzBJum2Fwjf/VnuGRYkhKCqqZ8gJ3OvmR50tInDV2jZ1DQgc3i550T5JDpToh dPBxZocIhzg+MBSRDXcJmHOx/7nQm3iQ6iLuwmXsRC6f5FbFefk9EjuTKcLMvBsEx+2DEx0E UnmJ4hVg7u1PQ+2Oy+Lh/opK/BDiqlQ8Pz2jiXv5xkECvr/3Sv59hlOCZMOaiLTTjtOIU7Tq 7ut6OL64oAq+zsFNBFXLn5EBEADn1959INH2cwYJv0tsxf5MUCghCj/CA/lc/LMthqQ773ga uB9mN+F1rE9cyyXb6jyOGn+GUjMbnq1o121Vm0+neKHUCBtHyseBfDXHA6m4B3mUTWo13nid 0e4AM71r0DS8+KYh6zvweLX/LL5kQS9GQeT+QNroXcC1NzWbitts6TZ+IrPOwT1hfB4WNC+X 2n4AzDqp3+ILiVST2DT4VBc11Gz6jijpC/KI5Al8ZDhRwG47LUiuQmt3yqrmN63V9wzaPhC+ xbwIsNZlLUvuRnmBPkTJwwrFRZvwu5GPHNndBjVpAfaSTOfppyKBTccu2AXJXWAE1Xjh6GOC 8mlFjZwLxWFqdPHR1n2aPVgoiTLk34LR/bXO+e0GpzFXT7enwyvFFFyAS0Nk1q/7EChPcbRb hJqEBpRNZemxmg55zC3GLvgLKd5A09MOM2BrMea+l0FUR+PuTenh2YmnmLRTro6eZ/qYwWkC u8FFIw4pT0OUDMyLgi+GI1aMpVogTZJ70FgV0pUAlpmrzk/bLbRkF3TwgucpyPtcpmQtTkWS gDS50QG9DR/1As3LLLcNkwJBZzBG6PWbvcOyrwMQUF1nl4SSPV0LLH63+BrrHasfJzxKXzqg rW28CTAE2x8qi7e/6M/+XXhrsMYG+uaViM7n2je3qKe7ofum3s4vq7oFCPsOgwARAQABwsFl BBgBAgAPBQJVy5+RAhsMBQkJZgGAAAoJEE3eEPcA/4NagOsP/jPoIBb/iXVbM+fmSHOjEshl KMwEl/m5iLj3iHnHPVLBUWrXPdS7iQijJA/VLxjnFknhaS60hkUNWexDMxVVP/6lbOrs4bDZ NEWDMktAeqJaFtxackPszlcpRVkAs6Msn9tu8hlvB517pyUgvuD7ZS9gGOMmYwFQDyytpepo YApVV00P0u3AaE0Cj/o71STqGJKZxcVhPaZ+LR+UCBZOyKfEyq+ZN311VpOJZ1IvTExf+S/5 lqnciDtbO3I4Wq0ArLX1gs1q1XlXLaVaA3yVqeC8E7kOchDNinD3hJS4OX0e1gdsx/e6COvy qNg5aL5n0Kl4fcVqM0LdIhsubVs4eiNCa5XMSYpXmVi3HAuFyg9dN+x8thSwI836FoMASwOl C7tHsTjnSGufB+D7F7ZBT61BffNBBIm1KdMxcxqLUVXpBQHHlGkbwI+3Ye+nE6HmZH7IwLwV W+Ajl7oYF+jeKaH4DZFtgLYGLtZ1LDwKPjX7VAsa4Yx7S5+EBAaZGxK510MjIx6SGrZWBrrV TEvdV00F2MnQoeXKzD7O4WFbL55hhyGgfWTHwZ457iN9SgYi1JLPqWkZB0JRXIEtjd4JEQcx +8Umfre0Xt4713VxMygW0PnQt5aSQdMD58jHFxTk092mU+yIHj5LeYgvwSgZN4airXk5yRXl SE+xAvmumFBY Organization: Red Hat GmbH Message-ID: Date: Thu, 25 Jul 2019 17:21:30 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20190725151735.29334-1-mst@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Thu, 25 Jul 2019 15:21:36 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH v4] virtio-balloon: free pbp more aggressively X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , qemu-stable@nongnu.org, Paolo Bonzini , Igor Mammedov , Richard Henderson Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 25.07.19 17:18, Michael S. Tsirkin wrote: > Previous patches switched to a temporary pbp but that does not go far > enough: after device uses a buffer, guest is free to reuse it, so > tracking the page and freeing it later is wrong. > > Free and reset the pbp after we push each element. > > Fixes: ed48c59875b6 ("virtio-balloon: Safely handle BALLOON_PAGE_SIZE < host page size") > Cc: qemu-stable@nongnu.org #v4.0.0 > Cc: David Hildenbrand > Signed-off-by: Michael S. Tsirkin > --- > > changes from v2, v3: > v3 was same as v2, sent by mistake > v4 fixes a typo > > hw/virtio/virtio-balloon.c | 37 ++++++++++++++++--------------------- > > diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c > index fe9664e42c..25de154307 100644 > --- a/hw/virtio/virtio-balloon.c > +++ b/hw/virtio/virtio-balloon.c > @@ -41,22 +41,19 @@ typedef struct PartiallyBalloonedPage { > > static void virtio_balloon_pbp_free(PartiallyBalloonedPage *pbp) > { > - if (!pbp) { > + if (!pbp->bitmap) { > return; > } > g_free(pbp->bitmap); > - g_free(pbp); > + pbp->bitmap = NULL; > } > > -static PartiallyBalloonedPage *virtio_balloon_pbp_alloc(ram_addr_t base_gpa, > - long subpages) > +static void virtio_balloon_pbp_alloc(PartiallyBalloonedPage *pbp, > + ram_addr_t base_gpa, > + long subpages) > { > - PartiallyBalloonedPage *pbp = g_new0(PartiallyBalloonedPage, 1); > - > pbp->base_gpa = base_gpa; > pbp->bitmap = bitmap_new(subpages); > - > - return pbp; > } > > static bool virtio_balloon_pbp_matches(PartiallyBalloonedPage *pbp, > @@ -67,7 +64,7 @@ static bool virtio_balloon_pbp_matches(PartiallyBalloonedPage *pbp, > > static void balloon_inflate_page(VirtIOBalloon *balloon, > MemoryRegion *mr, hwaddr mr_offset, > - PartiallyBalloonedPage **pbp) > + PartiallyBalloonedPage *pbp) > { > void *addr = memory_region_get_ram_ptr(mr) + mr_offset; > ram_addr_t rb_offset, rb_aligned_offset, base_gpa; > @@ -104,22 +101,21 @@ static void balloon_inflate_page(VirtIOBalloon *balloon, > base_gpa = memory_region_get_ram_addr(mr) + mr_offset - > (rb_offset - rb_aligned_offset); > > - if (*pbp && !virtio_balloon_pbp_matches(*pbp, base_gpa)) { > + if (pbp->bitmap && !virtio_balloon_pbp_matches(pbp, base_gpa)) { > /* We've partially ballooned part of a host page, but now > * we're trying to balloon part of a different one. Too hard, > * give up on the old partial page */ > - virtio_balloon_pbp_free(*pbp); > - *pbp = NULL; > + virtio_balloon_pbp_free(pbp); > } > > - if (!*pbp) { > - *pbp = virtio_balloon_pbp_alloc(base_gpa, subpages); > + if (!pbp->bitmap) { > + virtio_balloon_pbp_alloc(pbp, base_gpa, subpages); > } > > set_bit((rb_offset - rb_aligned_offset) / BALLOON_PAGE_SIZE, > - (*pbp)->bitmap); > + pbp->bitmap); > > - if (bitmap_full((*pbp)->bitmap, subpages)) { > + if (bitmap_full(pbp->bitmap, subpages)) { > /* We've accumulated a full host page, we can actually discard > * it now */ > > @@ -127,8 +123,7 @@ static void balloon_inflate_page(VirtIOBalloon *balloon, > /* We ignore errors from ram_block_discard_range(), because it > * has already reported them, and failing to discard a balloon > * page is not fatal */ > - virtio_balloon_pbp_free(*pbp); > - *pbp = NULL; > + virtio_balloon_pbp_free(pbp); > } > } > > @@ -328,13 +323,14 @@ static void balloon_stats_set_poll_interval(Object *obj, Visitor *v, > static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) > { > VirtIOBalloon *s = VIRTIO_BALLOON(vdev); > - PartiallyBalloonedPage *pbp = NULL; > VirtQueueElement *elem; > MemoryRegionSection section; > > for (;;) { > + PartiallyBalloonedPage pbp = {}; > size_t offset = 0; > uint32_t pfn; > + > elem = virtqueue_pop(vq, sizeof(VirtQueueElement)); > if (!elem) { > break; > @@ -379,9 +375,8 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) > virtqueue_push(vq, elem, offset); > virtio_notify(vdev, vq); > g_free(elem); > + virtio_balloon_pbp_free(&pbp); > } > - > - virtio_balloon_pbp_free(pbp); > } > > static void virtio_balloon_receive_stats(VirtIODevice *vdev, VirtQueue *vq) > Works with hugetlbfs on x86 and LGTM: Reviewed-by: David Hildenbrand -- Thanks, David / dhildenb