From patchwork Mon Sep 18 14:41:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Markus Armbruster X-Patchwork-Id: 1836209 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=ZlDGhUDa; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4Rq76202cmz1ynX for ; Tue, 19 Sep 2023 00:51:21 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qiFTR-000511-E9; Mon, 18 Sep 2023 10:43:41 -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 1qiFSw-0003Cb-9x for qemu-devel@nongnu.org; Mon, 18 Sep 2023 10:43:10 -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 1qiFSt-0002uz-7T for qemu-devel@nongnu.org; Mon, 18 Sep 2023 10:43:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1695048185; 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=3yqLeYQ+wzrOKTYBgpuJP4VgHhHFEjpE7p+Go3JCE+g=; b=ZlDGhUDa04ck1qiik4vTWVdzJzc/RIH3YybUiES7uc1YdEeuyeTOVb4QiuMjNksigIKW3w mQ+TLJud/r4iJzA21c8+7W4PmhCCtSSf7SDvQdJlLHSyOgRCmXrdt6nuk9qepVihy2MHoN WCp0fSX2uZThkUnZ/rVHi1GMBuSd4fA= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-222-9m3l8agwMAaArqX3ga3IYg-1; Mon, 18 Sep 2023 10:42:22 -0400 X-MC-Unique: 9m3l8agwMAaArqX3ga3IYg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 2D80418175A4 for ; Mon, 18 Sep 2023 14:42:10 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.192.127]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0C11C2156702 for ; Mon, 18 Sep 2023 14:42:10 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 177E021E691A; Mon, 18 Sep 2023 16:42:07 +0200 (CEST) From: Markus Armbruster To: qemu-devel@nongnu.org Cc: quintela@redhat.com, peterx@redhat.com, leobras@redhat.com Subject: [PATCH 16/52] migration/rdma: Fix io_writev(), io_readv() methods to obey contract Date: Mon, 18 Sep 2023 16:41:30 +0200 Message-ID: <20230918144206.560120-17-armbru@redhat.com> In-Reply-To: <20230918144206.560120-1-armbru@redhat.com> References: <20230918144206.560120-1-armbru@redhat.com> MIME-Version: 1.0 Content-type: text/plain X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@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_NONE=0.001, SPF_PASS=-0.001 autolearn=ham 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org QIOChannelClass methods qio_channel_rdma_readv() and qio_channel_rdma_writev() violate their method contract when rdma->error_state is non-zero: 1. They return whatever is in rdma->error_state then. Only -1 will be fine. -2 will be misinterpreted as "would block". Anything less than -2 isn't defined in the contract. A positive value would be misinterpreted as success, but I believe that's not actually possible. 2. They neglect to set an error then. If something up the call stack dereferences the error when failure is returned, it will crash. If it ignores the return value and checks the error instead, it will miss the error. Crap like this happens when return statements hide in macros, especially when their uses are far away from the definition. I elected not to investigate how callers are impacted. Expand the two bad macro uses, so we can set an error and return -1. The next commit will then get rid of the macro altogether. Signed-off-by: Markus Armbruster Reviewed-by: Fabiano Rosas Reviewed-by: Li Zhijian --- migration/rdma.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/migration/rdma.c b/migration/rdma.c index 2173cb076f..30e6dff875 100644 --- a/migration/rdma.c +++ b/migration/rdma.c @@ -2761,7 +2761,11 @@ static ssize_t qio_channel_rdma_writev(QIOChannel *ioc, return -1; } - CHECK_ERROR_STATE(); + if (rdma->error_state) { + error_setg(errp, + "RDMA is in an error state waiting migration to abort!"); + return -1; + } /* * Push out any writes that @@ -2847,7 +2851,11 @@ static ssize_t qio_channel_rdma_readv(QIOChannel *ioc, return -1; } - CHECK_ERROR_STATE(); + if (rdma->error_state) { + error_setg(errp, + "RDMA is in an error state waiting migration to abort!"); + return -1; + } for (i = 0; i < niov; i++) { size_t want = iov[i].iov_len;