From patchwork Wed Feb 26 15:52:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11406633 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 50B8C1805 for ; Wed, 26 Feb 2020 15:56:12 +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 2763521556 for ; Wed, 26 Feb 2020 15:56:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="NoS63jTE" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2763521556 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+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:46242 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j6z2h-0007mR-9i for patchwork-qemu-devel@patchwork.kernel.org; Wed, 26 Feb 2020 10:56:11 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:34032) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j6z0W-00037F-6l for qemu-devel@nongnu.org; Wed, 26 Feb 2020 10:53:57 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j6z0V-000309-79 for qemu-devel@nongnu.org; Wed, 26 Feb 2020 10:53:56 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:57048 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j6z0V-0002zs-3P for qemu-devel@nongnu.org; Wed, 26 Feb 2020 10:53:55 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1582732434; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/kEgul7L6JaBdLS5nxEDOuGO0ikOJi+PGHq3Ia4gucw=; b=NoS63jTEuT3g1jPEjDP+VgZav6D1NJaPWGQTaRYezRbuLI3PaGfVMgWqX0KXTaViFl37uv 4lSrT1P9wVzMNwDxTQUUWyCTyrUh9NK7Gi/5aY4/0sCRaVpMmJZUNSI7fforSYJcNo5nI/ zcw36gJAj6nmLlPv1ieR+9tsFwUWLww= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-325-1Jb_Mj-GNf6PvjhlYmzQBw-1; Wed, 26 Feb 2020 10:53:51 -0500 X-MC-Unique: 1Jb_Mj-GNf6PvjhlYmzQBw-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 19605107ACC4; Wed, 26 Feb 2020 15:53:50 +0000 (UTC) Received: from t480s.redhat.com (ovpn-117-196.ams2.redhat.com [10.36.117.196]) by smtp.corp.redhat.com (Postfix) with ESMTP id 66F8A100EBAF; Wed, 26 Feb 2020 15:53:43 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v3 06/13] exec: Relax range check in ram_block_discard_range() Date: Wed, 26 Feb 2020 16:52:57 +0100 Message-Id: <20200226155304.60219-7-david@redhat.com> In-Reply-To: <20200226155304.60219-1-david@redhat.com> References: <20200226155304.60219-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.120 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 , Juan Quintela , David Hildenbrand , "Dr . David Alan Gilbert" , Peter Xu , Paolo Bonzini , Richard Henderson Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" We want to make use of ram_block_discard_range() in the RAM block resize callback when growing a RAM block, *before* used_length is changed. Let's relax the check. We always have a reserved mapping for the whole max_length, so we cannot corrupt unrelated data. Reviewed-by: Peter Xu Cc: Richard Henderson Cc: Paolo Bonzini Cc: Eduardo Habkost Cc: Peter Xu Signed-off-by: David Hildenbrand --- exec.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/exec.c b/exec.c index d30a5d297a..9d351a7492 100644 --- a/exec.c +++ b/exec.c @@ -3876,7 +3876,7 @@ int ram_block_discard_range(RAMBlock *rb, uint64_t start, size_t length) goto err; } - if ((start + length) <= rb->used_length) { + if ((start + length) <= rb->max_length) { bool need_madvise, need_fallocate; if (!QEMU_IS_ALIGNED(length, rb->page_size)) { error_report("ram_block_discard_range: Unaligned length: %zx", @@ -3943,7 +3943,7 @@ int ram_block_discard_range(RAMBlock *rb, uint64_t start, size_t length) } else { error_report("ram_block_discard_range: Overrun block '%s' (%" PRIu64 "/%zx/" RAM_ADDR_FMT")", - rb->idstr, start, length, rb->used_length); + rb->idstr, start, length, rb->max_length); } err: