From nobody Sat Sep 21 00:59:43 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of redhat.com designates 209.132.183.28 as permitted sender) client-ip=209.132.183.28; envelope-from=libvir-list-bounces@redhat.com; helo=mx1.redhat.com; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=libvir-list-bounces@redhat.com; dmarc=pass(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1561030889; cv=none; d=zoho.com; s=zohoarc; b=fNkY4UhBx8FV1TClirsvLkzl59B8rDKrd8LdA+3u0VaAR0/XlssekAWDAFjEE1n3Brw58rC/ceVzIU1sYKu367gLgpXrjf3YCSOLJveNoBaKYgh7wRTTmG/bD1OYfzY6gsh5RIWATmkUPshkCPuvMAJElV9LSBb18HL0TUfR6ho= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1561030889; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:Sender:Subject:To:ARC-Authentication-Results; bh=poxzgS+9CypVCzUphJehZBTwkRSRMtv6+HnwWUr+7go=; b=T9favRrbqI8Jy/UmSL3aS/UeWigg9anlylrhsk7GN72snlLuUytRvoVsJvk/uBNjP6QpECNJXl91HtoYgJnDU7mQGlKtrdJ49Vf8XlIoxA6SqCa0YJqcFtaucskWHcClFME35Pw48PfCj9f3hZ/OKc/PPNzAWTOkcPM2e2p/gDc= ARC-Authentication-Results: i=1; mx.zoho.com; spf=pass (zoho.com: domain of redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=libvir-list-bounces@redhat.com; dmarc=pass header.from= (p=none dis=none) header.from= Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by mx.zohomail.com with SMTPS id 1561030889499145.87824200482623; Thu, 20 Jun 2019 04:41:29 -0700 (PDT) Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 08257C059B9F; Thu, 20 Jun 2019 11:41:26 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D529619C67; Thu, 20 Jun 2019 11:41:25 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 7C5A91806B0F; Thu, 20 Jun 2019 11:41:25 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id x5KBfNq2001903 for ; Thu, 20 Jun 2019 07:41:23 -0400 Received: by smtp.corp.redhat.com (Postfix) id E29866092E; Thu, 20 Jun 2019 11:41:23 +0000 (UTC) Received: from dell-r430-03.lab.eng.brq.redhat.com (dell-r430-03.lab.eng.brq.redhat.com [10.37.153.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id E0CE3608D0; Thu, 20 Jun 2019 11:41:20 +0000 (UTC) From: Igor Mammedov To: qemu-devel@nongnu.org Date: Thu, 20 Jun 2019 07:41:16 -0400 Message-Id: <20190620114116.27254-1-imammedo@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-loop: libvir-list@redhat.com Cc: libvir-list@redhat.com, ehabkost@redhat.com Subject: [libvirt] [PATCH] deprecate -mem-path fallback to anonymous RAM X-BeenThere: libvir-list@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: Development discussions about the libvirt library & tools List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: libvir-list-bounces@redhat.com Errors-To: libvir-list-bounces@redhat.com X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Thu, 20 Jun 2019 11:41:28 +0000 (UTC) Content-Type: text/plain; charset="utf-8" Fallback might affect guest or worse whole host performance or functionality if backing file were used to share guest RAM with another process. Patch deprecates fallback so that we could remove it in future and ensure that QEMU will provide expected behavior and fail if it can't use user provided backing file. Signed-off-by: Igor Mammedov Reviewed-by: Daniel P. Berrang=C3=A9 Reviewed-by: Dr. David Alan Gilbert --- PS: Patch is written on top of [PATCH v4 0/3] numa: deprecate '-numa node, mem' and default memory dist= ribution to avoid conflicts in qemu-deprecated.texi numa.c | 4 ++-- qemu-deprecated.texi | 8 ++++++++ 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/numa.c b/numa.c index 91a29138a2..53d67b8ad9 100644 --- a/numa.c +++ b/numa.c @@ -494,8 +494,8 @@ static void allocate_system_memory_nonnuma(MemoryRegion= *mr, Object *owner, if (mem_prealloc) { exit(1); } - error_report("falling back to regular RAM allocation."); - + warn_report("falling back to regular RAM allocation. " + "Fallback to RAM allocation is deprecated."); /* Legacy behavior: if allocation failed, fall back to * regular RAM allocation. */ diff --git a/qemu-deprecated.texi b/qemu-deprecated.texi index 2fe9b72121..2193705644 100644 --- a/qemu-deprecated.texi +++ b/qemu-deprecated.texi @@ -112,6 +112,14 @@ QEMU using implicit generic or board specific splittin= g rule. Use @option{memdev} with @var{memory-backend-ram} backend or @option{mem} = (if it's supported by used machine type) to define mapping explictly instead. =20 +@subsection -mem-path fallback to RAM (since 4.1) +Currently if system memory allocation from file pointed by @option{mem-pat= h} +fails, QEMU fallbacks to allocating from anonymous RAM. Which might result +in unpredictable behavior since provided backing file wasn't used. In futu= re +QEMU will not fallback and fail to start up, so user could fix his/her QEM= U/host +configuration or explicitly use -m without -mem-path if system memory allo= cated +from anonymous RAM suits usecase. + @section QEMU Machine Protocol (QMP) commands =20 @subsection block-dirty-bitmap-add "autoload" parameter (since 2.12.0) --=20 2.18.1 -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list