From patchwork Wed Nov 24 09:29:47 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Henrique Barboza X-Patchwork-Id: 12636479 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 EB458C433F5 for ; Wed, 24 Nov 2021 09:37:08 +0000 (UTC) Received: from localhost ([::1]:59094 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mpoiC-0007Np-48 for qemu-devel@archiver.kernel.org; Wed, 24 Nov 2021 04:37:08 -0500 Received: from eggs.gnu.org ([209.51.188.92]:56494) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mpobM-0000F8-RJ; Wed, 24 Nov 2021 04:30:04 -0500 Received: from [2607:f8b0:4864:20::a32] (port=42503 helo=mail-vk1-xa32.google.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1mpobJ-0006hk-Ie; Wed, 24 Nov 2021 04:30:04 -0500 Received: by mail-vk1-xa32.google.com with SMTP id b125so1063472vkb.9; Wed, 24 Nov 2021 01:30:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=INU73d/uF2ivB+x0H+8RzqTTu5ZxmTrDWSWRgnsrDZ8=; b=pC7eNY14KmCFvYlVefZsflmXdIsSTetzO11hgRgp5xwTL7+czIgeRoMyVFgg/lK1EL w05OgqIxgs2RhnBYjZ54/lZ7ZMyUm1qfeubPgu05L5G/0R87pWaqCjW8Zz/AbFseJ3eI D2pJALY4Om7Q8Bbd+I4gi/3DCC6vtEjC/2ZBF64y4aCcvL52Te3OoZcVKGpFiCflnfXi z0UYYyYWdsAdP0U167hqW/FrGpX7L1aHS/MUPrU20Z2/sRtlq+Np1PDb6WsUhR7EttFl xRJd3D8z2jjjfcFf7VMrQF0jSLqFC+Fiqj2FdjcXi/wml+USUEjDXMjlMDgP9b2cwHIk AxBQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=INU73d/uF2ivB+x0H+8RzqTTu5ZxmTrDWSWRgnsrDZ8=; b=2DPwjoL26WD7O2bYQWFKWxmyu7kuAKFJ2SCAsHOz4cTBhOgV4Cvra5tlVDcDsn7LuF fwqGIopHlKGX+PN1ESmUlCDBUDBu4Q7tTwhprAWYR1D2MeJ6oZvY9ii4w4qJCq/4doac WoH+wHqny/m8mEM97No3Y0KosKGuCcRYR9HhOwC1tXzui0TtQ9lAoQk8aenS0fmLb9dn J/TJ/V/cvIP3Kz0xadodYTHDj+PjnK125GT3yYrztrZfAcfodbMjW7zMQtHHjqJVHYkl teuIa5R+W83bCaioOhB1d6hEZLBe/wfeo6vZo0qcYZn619oFUlk+2JXTPjXvu8olN4At tf2Q== X-Gm-Message-State: AOAM531eX3CrUFKA8LnjyRaaNu4NC3AtPoFxDj0edic7ZnoHyu1NfLxw YwciP9BlyqQ8obdXUpGSPVCbxaQDGe4= X-Google-Smtp-Source: ABdhPJzYYVi+9koubxZ0cjUCwOHOf5akj7rRGIisn7zh92bydH7DJ1Kl8nwG5fBHr7URvthKxwHacA== X-Received: by 2002:a05:6122:114c:: with SMTP id p12mr24105499vko.21.1637746199618; Wed, 24 Nov 2021 01:29:59 -0800 (PST) Received: from rekt.ibmuc.com ([191.19.215.188]) by smtp.gmail.com with ESMTPSA id m15sm7682583vkl.40.2021.11.24.01.29.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 24 Nov 2021 01:29:59 -0800 (PST) From: Daniel Henrique Barboza To: qemu-devel@nongnu.org Subject: [PATCH for-7.0 v2 1/2] ivshmem.c: change endianness to LITTLE_ENDIAN Date: Wed, 24 Nov 2021 06:29:47 -0300 Message-Id: <20211124092948.335389-2-danielhb413@gmail.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211124092948.335389-1-danielhb413@gmail.com> References: <20211124092948.335389-1-danielhb413@gmail.com> MIME-Version: 1.0 X-Host-Lookup-Failed: Reverse DNS lookup failed for 2607:f8b0:4864:20::a32 (failed) Received-SPF: pass client-ip=2607:f8b0:4864:20::a32; envelope-from=danielhb413@gmail.com; helo=mail-vk1-xa32.google.com X-Spam_score_int: -10 X-Spam_score: -1.1 X-Spam_bar: - X-Spam_report: (-1.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_ENVFROM_END_DIGIT=0.25, FREEMAIL_FROM=0.001, PDS_HP_HELO_NORDNS=0.001, RCVD_IN_DNSWL_NONE=-0.0001, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no 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: , Cc: thuth@redhat.com, Daniel Henrique Barboza , qemu-ppc@nongnu.org, clg@kaod.org, david@gibson.dropbear.id.au Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" The ivshmem device, as with most PCI devices, uses little endian byte order. However, the endianness of its mmio_ops is marked as DEVICE_NATIVE_ENDIAN. This presents not only the usual problems with big endian hosts but also with PowerPC little endian hosts as well, since the Power architecture in QEMU uses big endian hardware (XIVE controller, PCI Host Bridges, etc) even if the host is in little endian byte order. As it is today, the IVPosition of the device will be byte swapped when running in Power BE and LE. This can be seen by changing the existing qtest 'ivshmem-test' to run in ppc64 hosts and printing the IVPOSITION regs in test_ivshmem_server() right after the VM ids assert. For x86_64 the VM id values read are '0' and '1', for ppc64 (tested in a Power8 RHEL 7.9 BE server) and ppc64le (tested in a Power9 RHEL 8.6 LE server) the ids will be '0' and '0x1000000'. Change this device to LITTLE_ENDIAN fixes the issue for Power hosts of both endianness, and every other big-endian architecture that might use this device, without impacting x86 users. Fixes: cb06608e17f8 ("ivshmem: convert to memory API") Resolves: https://gitlab.com/qemu-project/qemu/-/issues/168 Signed-off-by: Daniel Henrique Barboza Reviewed-by: Philippe Mathieu-Daudé --- hw/misc/ivshmem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c index 1ba4a98377..299837e5c1 100644 --- a/hw/misc/ivshmem.c +++ b/hw/misc/ivshmem.c @@ -243,7 +243,7 @@ static uint64_t ivshmem_io_read(void *opaque, hwaddr addr, static const MemoryRegionOps ivshmem_mmio_ops = { .read = ivshmem_io_read, .write = ivshmem_io_write, - .endianness = DEVICE_NATIVE_ENDIAN, + .endianness = DEVICE_LITTLE_ENDIAN, .impl = { .min_access_size = 4, .max_access_size = 4,