From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: passt.top; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: passt.top; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=TgnbblJT; dkim-atps=neutral Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by passt.top (Postfix) with ESMTPS id 06DE75A061C for ; Thu, 16 Apr 2026 18:21:45 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1776356504; 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=VzHKcunmngSOYu/9bwnRXJQrGJKn+phDX093eHQ/GYk=; b=TgnbblJTE+xhPSb658VQqdwiK+sOBAPId7sBUNFnQVMbbEG0lXXGSdzQyDyrhn7CMNGzcQ TKmoxGXU3uhHqokBf5ppZQbJ6K62bZrnYklKgbJCq5HVjxrTaWnj5n7iAXrqzAg+oxLcOz /tzYtvRRhd0aoebmqCKbE6tmOM6ejG8= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-197-XC1Yck4zNOWQpEL_oLgrgg-1; Thu, 16 Apr 2026 12:21:43 -0400 X-MC-Unique: XC1Yck4zNOWQpEL_oLgrgg-1 X-Mimecast-MFC-AGG-ID: XC1Yck4zNOWQpEL_oLgrgg_1776356502 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (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-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 1E3D01955F0E for ; Thu, 16 Apr 2026 16:21:42 +0000 (UTC) Received: from lenovo-t14s.redhat.corp (headnet01.pony-001.prod.iad2.dc.redhat.com [10.2.32.101]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 50F081800446; Thu, 16 Apr 2026 16:21:41 +0000 (UTC) From: Laurent Vivier To: passt-dev@passt.top Subject: [PATCH v2 0/2] vhost-user, dhcp: Fix iPXE network boot over vhost-user Date: Thu, 16 Apr 2026 18:21:38 +0200 Message-ID: <20260416162140.3830027-1-lvivier@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: 4cwaV76EAMCNOFNawpGjzYrmDRZI5EWHL6Y9D9EhTe8_1776356502 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Message-ID-Hash: MTIUILZARTY63RPZQFWFGBJ7E6UAVJA6 X-Message-ID-Hash: MTIUILZARTY63RPZQFWFGBJ7E6UAVJA6 X-MailFrom: lvivier@redhat.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: Laurent Vivier X-Mailman-Version: 3.3.8 Precedence: list List-Id: Development discussion and patches for passt Archived-At: Archived-At: List-Archive: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: iPXE network boot over vhost-user was broken because passt unconditionally skipped TCP/UDP checksum computation, relying on VIRTIO_NET_HDR_F_DATA_VALID to tell the guest the checksums were valid. Linux guests happened to work because their virtio-net driver honours DATA_VALID regardless of feature negotiation, but iPXE verifies checksums strictly and never negotiates VIRTIO_NET_F_GUEST_CSUM. This series handles correctly VIRTIO_NET_F_GUEST_CSUM feature to fix that and adds a minimal --dhcp-boot option that populates the BOOTP/DHCP 'file' field, providing just enough for testing iPXE UDP and TCP support. This can be tested as following: - Create an ipxe file configuration cat > boot-alpine.ipxe <:8080/boot-alpine.ipxe --vhost-user - Start QEMU without boot disk but with passt as networking backend Based-on: 20260416161618.3826904-1-lvivier@redhat.com v2: - Added Reviewed-by from David Gibson on both patches - Rebased on top of v6 TCP series Laurent Vivier (2): vhost_user: Offer VIRTIO_NET_F_GUEST_CSUM dhcp: Add --dhcp-boot option to set boot filename in DHCP replies conf.c | 10 ++++++++++ dhcp.c | 5 ++++- passt.1 | 6 ++++++ passt.h | 1 + tcp_vu.c | 8 ++++++-- udp_vu.c | 7 ++++--- vhost_user.c | 1 + 7 files changed, 32 insertions(+), 6 deletions(-) -- 2.53.0