From patchwork Wed Aug 23 15:34:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13362781 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 1D891EE49B0 for ; Wed, 23 Aug 2023 15:36:31 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qYpsn-000248-Tp; Wed, 23 Aug 2023 11:34:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qYpsF-0001sq-8f for qemu-devel@nongnu.org; Wed, 23 Aug 2023 11:34:23 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qYpsC-0007qp-OT for qemu-devel@nongnu.org; Wed, 23 Aug 2023 11:34:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1692804859; 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; bh=H2FvnCY0jyb5kYADKKlHrV2ZhVsNCKzc/9Izuh2JpUc=; b=Zqf4cNBCeaq68iKCd2VWpOOqt20qybXGOtDV7w7LOOQ1bAdZfh8mPpLtWmg8sbjAQ4Rdeb X1sKE2G2ZI/sAyStBSSiSm2hg3P3S8KIYAzWHQaaIgLuSIuYfqpKD+TfUwRAYezFpygE/e yPMYlBe0Ambt04t/Fe2gU65RQf4MdJs= Received: from mimecast-mx02.redhat.com (66.187.233.73 [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-628-gTprVC_tOpyTX1NCst1vjA-1; Wed, 23 Aug 2023 11:34:16 -0400 X-MC-Unique: gTprVC_tOpyTX1NCst1vjA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id B472229AA38A; Wed, 23 Aug 2023 15:34:15 +0000 (UTC) Received: from t14s.fritz.box (unknown [10.39.193.128]) by smtp.corp.redhat.com (Postfix) with ESMTP id E02E71121314; Wed, 23 Aug 2023 15:34:12 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: qemu-ppc@nongnu.org, David Hildenbrand , Paolo Bonzini , Peter Xu , Igor Mammedov , Thiner Logoer , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , =?utf-8?q?Dani?= =?utf-8?q?el_P_=2E_Berrang=C3=A9?= , Stefan Hajnoczi , Elena Ufimtseva , Jagannathan Raman , "Michael S. Tsirkin" , Ani Sinha , Xiao Guangrong , Daniel Henrique Barboza , Greg Kurz , Eric Blake , Markus Armbruster , Eduardo Habkost Subject: [PATCH v3 00/11] memory-backend-file related improvements and VM templating support Date: Wed, 23 Aug 2023 17:34:00 +0200 Message-ID: <20230823153412.832081-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Received-SPF: pass client-ip=170.10.133.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org This is the result of the previous discussion of: * "[PATCH v2] softmmu/physmem: try opening file readonly before failure in file_ram_open" [1] * "[PATCH v1 0/3] softmmu/physmem: file_ram_open() readonly improvements" [2] After looking into various ways to avoid a new parameter for memory-backend-file to cleanly support VM templating with R/O files, I concluded that it might be easier and cleaner to hust have a new parameter. The alternatives all had their own problems. Looking back, we could have designed the "readonly=on/off" parameter slightly differently. So this series adds a new "rom=on/off/auto" option and wires it up internally. It uses new internal RAM flags to improve qemu_ram_remap() and ram_block_discard_range(). Further, improve file_ram_open() with readonly=on and update+add some documentation. While working on this and testing some configurations, I realized that an NVDIMM with label data on ROM does not work as expected (QEMU crashes). Fix included as patch #1. v2 -> v3: - "softmmu/physmem: Distinguish between file access mode and mmap protection" -> Use !!(ram_flags & RAM_READONLY); - "backends/hostmem-file: Add "rom" property to support VM templating with R/O files" -> Improved documentation in qapi/qom.json and qemu-options.hx - "docs: Start documenting VM templating" -> Create proper RST and link it -> Add "Security Alert" section -> Add MAINTAINER entry - "softmmu/physmem: Hint that "readonly=on,rom=off" exists when opening file R/W for private mapping fails" -> Added - "machine: Improve error message when using default RAM backend id" -> Added Cc: Paolo Bonzini Cc: Peter Xu Cc: Igor Mammedov Cc: Thiner Logoer Cc: "Philippe Mathieu-Daudé" Cc: Daniel P. Berrangé Cc: Stefan Hajnoczi Cc: Elena Ufimtseva Cc: Jagannathan Raman Cc: "Michael S. Tsirkin" Cc: Ani Sinha Cc: Xiao Guangrong Cc: Daniel Henrique Barboza Cc: Greg Kurz Cc: Eric Blake Cc: Markus Armbruster Cc: "Daniel P. Berrangé" Cc: Eduardo Habkost [1] https://lkml.kernel.org/r/20230726145912.88545-1-logoerthiner1@163.com [2] https://lkml.kernel.org/r/20230807190736.572665-1-david@redhat.com David Hildenbrand (11): nvdimm: Reject writing label data to ROM instead of crashing QEMU softmmu/physmem: Distinguish between file access mode and mmap protection backends/hostmem-file: Add "rom" property to support VM templating with R/O files softmmu/physmem: Remap with proper protection in qemu_ram_remap() softmmu/physmem: Bail out early in ram_block_discard_range() with readonly files softmmu/physmem: Fail creation of new files in file_ram_open() with readonly=true softmmu/physmem: Never return directories from file_ram_open() docs: Don't mention "-mem-path" in multi-process.rst docs: Start documenting VM templating softmmu/physmem: Hint that "readonly=on,rom=off" exists when opening file R/W for private mapping fails machine: Improve error message when using default RAM backend id MAINTAINERS | 1 + backends/hostmem-file.c | 61 ++++++++++++++++- docs/devel/multi-process.rst | 5 +- docs/system/index.rst | 1 + docs/system/vm-templating.rst | 125 ++++++++++++++++++++++++++++++++++ hw/acpi/nvdimm.c | 11 ++- hw/core/machine.c | 4 +- hw/mem/nvdimm.c | 10 ++- hw/ppc/spapr_nvdimm.c | 3 +- include/exec/memory.h | 14 ++-- include/exec/ram_addr.h | 8 +-- include/hw/mem/nvdimm.h | 6 ++ qapi/qom.json | 17 ++++- qemu-options.hx | 16 ++++- softmmu/memory.c | 8 +-- softmmu/physmem.c | 93 +++++++++++++++++++------ 16 files changed, 336 insertions(+), 47 deletions(-) create mode 100644 docs/system/vm-templating.rst