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 Received: from lists1p.gnu.org (lists1p.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 D562FC79FAD for ; Wed, 9 Sep 2026 13:06:03 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1x4HzV-0008BQ-Ay; Wed, 09 Sep 2026 09:05:29 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1x4HwG-0007Sk-Tw for qemu-devel@nongnu.org; Wed, 09 Sep 2026 09:02:08 -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 1x4HwC-0000xB-0C for qemu-devel@nongnu.org; Wed, 09 Sep 2026 09:02:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1788958922; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=fG/VZT9CKqIlbY1q7dW+5I9tUbZVNc+jlNU+M6BEZZ0=; b=it3z4HM0TSARp6GcGVoqkt+5lEeGladVQgT1qieJnPwqkCi6hS36hAx8AwYe2mY+gxB7hh efddHza/OZMhJyampNC4KDwd/l40ZpHlO0kNOpDtGBuo+BfZn4eGMocNVRXXjOcdWpt36/ Ht1VfJ122YTfsdgWItLvHWQKWHKAyZg= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-617-zQkv2Xj-ODWYH7KBUrYBZg-1; Wed, 09 Sep 2026 08:59:53 -0400 X-MC-Unique: zQkv2Xj-ODWYH7KBUrYBZg-1 X-Mimecast-MFC-AGG-ID: zQkv2Xj-ODWYH7KBUrYBZg_1788958792 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id A59071800848; Wed, 9 Sep 2026 12:59:52 +0000 (UTC) Received: from Alexs-MacBook-Air.redhat.corp (headnet04.pony-001.prod.iad2.dc.redhat.com [10.2.32.116]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id ACC713000218; Wed, 9 Sep 2026 12:59:49 +0000 (UTC) From: Alex Fishman To: qemu-devel@nongnu.org Cc: mst@redhat.com, sgarzare@redhat.com, farosas@suse.de, lvivier@redhat.com, pbonzini@redhat.com, Alex Fishman Subject: [PATCH v1 0/2] vhost: Handle vrings crossing virtio-mem slots Date: Wed, 9 Sep 2026 15:59:21 +0300 Message-ID: <20260909125923.75340-1-afishman@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Received-SPF: pass client-ip=170.10.133.124; envelope-from=afishman@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_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-Mailman-Approved-At: Wed, 09 Sep 2026 09:05:26 -0400 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development 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 Virtio-mem dynamic memslots are intentionally exposed as separate memory regions. If a guest places a vring part across two adjacent slots, a later memory update fails vhost ring verification because the complete ring part is not contained in one vhost memory region. Coalesce coherent adjacent sections only when a descriptor table, available ring, or used ring crosses their boundary. Unrelated unmergeable sections remain separate so they can still be updated independently. Patch 2 adds an end-to-end qtest reproducer using a fake vhost-user backend and virtio-mem dynamic memslots. It also verifies that a newly activated slot is not folded into the merge required by the crossing vring. Tested with the vhost-user/mem-slots/boundary qtest. Buglink: https://redhat.atlassian.net/browse/RHEL-146583 Alex Fishman (2): vhost: coalesce unmergeable sections across vring boundaries tests/qtest: Add vhost-user memslot boundary test hw/virtio/vhost.c | 72 ++++++- tests/qtest/vhost-user-test.c | 395 +++++++++++++++++++++++++++++++++- 2 files changed, 452 insertions(+), 15 deletions(-) base-commit: ff1d2d19d7e24893e2012d879f8e73077e17b9bd -- 2.52.0