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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5B9DBC04A94 for ; Mon, 14 Aug 2023 17:48:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231312AbjHNRru (ORCPT ); Mon, 14 Aug 2023 13:47:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59612 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231401AbjHNRrZ (ORCPT ); Mon, 14 Aug 2023 13:47:25 -0400 Received: from mail-oo1-xc34.google.com (mail-oo1-xc34.google.com [IPv6:2607:f8b0:4864:20::c34]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 35C0B10D0 for ; Mon, 14 Aug 2023 10:47:25 -0700 (PDT) Received: by mail-oo1-xc34.google.com with SMTP id 006d021491bc7-56c85b723cfso2934343eaf.3 for ; Mon, 14 Aug 2023 10:47:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; t=1692035244; x=1692640044; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=Y/yNh4F2KqOT+gKhbfMAb20rsFiF8tD3IHTN/BfkK/o=; b=Nnz1d6Q95SoJZqyUmSGv/mULK+qIzASlvU7AAxuOXr7Ap6igT/sLL3+gSSpHpkoB9d nq0FRws0EU8HEIf/UAzptDEUWGEE34uxX7M7wdemum4vt+i8XK0yjWpnP6k6RLQOlYca dPoCaU+Az0Ez4ogVRalWR9rBLicAI0FE3KQlaJxmfFUU4xsacst0OFvU4PfESdDv6C0v rfdVU0Y3kbPD1Wx43UulHldGLfwHHgUYZeqWz8Gin+PoN2qtQ0YA5Zq2OVexuPN5Afyl oUMNjZX2i9gx+2K9cvLivBoiioPUR77MotF6WQlXmHva4gC2yxzxZ617LoiIvIfsnM8b F1cA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692035244; x=1692640044; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=Y/yNh4F2KqOT+gKhbfMAb20rsFiF8tD3IHTN/BfkK/o=; b=Wd4lM2vGdXxTstdtH4zXRkLMwhaTBQGHeMp8oLMi1xFbEQLRP+YBiUnwu3WyE6vA5s cIQR2ObJFbSmdXVz0EeN1gJ9fLntJUc0ndiQuQv4uU+DPBzZQDaepXDgaOODVNv+BJcf ZsQKNGchNRB0gKTk+8n/2P4j04IcXu/zBqu9prieUDpeT4EQcbNH09IYFYMXv+F5PCWX NPJfYl1H/qgThxmZVmKvKOI5yhhw+Nh7+wSQYJEUk/HvJGdehRj4p+OP7htO5XPAMYRz G6UaPJZbGKcELN8fu7PEtFHp+X7zGaiM2amHXaKzhuyZKoy5edtT9ZiAGJCNvCNXhnv4 xtCg== X-Gm-Message-State: AOJu0YyAFCmKBVX2U8iVk0hdgNIhLQtCU0FM86m7NbwNQMRF/JnrWfy6 q+w9o7LFALiof5d1yCta/VRZQg== X-Google-Smtp-Source: AGHT+IHKtophzNepnrOSKqJW2gtkKecjEJCHZKJbB96GaU/SIQr5jKKtpBh+9NCgIHhPr2b3svWbtQ== X-Received: by 2002:a05:6358:c15:b0:129:c477:289c with SMTP id f21-20020a0563580c1500b00129c477289cmr8037336rwj.26.1692035244459; Mon, 14 Aug 2023 10:47:24 -0700 (PDT) Received: from ziepe.ca ([206.223.160.26]) by smtp.gmail.com with ESMTPSA id 11-20020ac8564b000000b003ef189ffa82sm3228482qtt.90.2023.08.14.10.47.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 14 Aug 2023 10:47:23 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.95) (envelope-from ) id 1qVbf1-0070BL-2Q; Mon, 14 Aug 2023 14:47:23 -0300 Date: Mon, 14 Aug 2023 14:47:23 -0300 From: Jason Gunthorpe To: Stefan Hajnoczi Cc: kvm@vger.kernel.org, "Tian, Kevin" , linux-kernel@vger.kernel.org, Alex Williamson Subject: Re: [PATCH 1/4] vfio: trivially use __aligned_u64 for ioctl structs Message-ID: References: <20230809210248.2898981-1-stefanha@redhat.com> <20230809210248.2898981-2-stefanha@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230809210248.2898981-2-stefanha@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 09, 2023 at 05:02:45PM -0400, Stefan Hajnoczi wrote: > u64 alignment behaves differently depending on the architecture and so > offers __aligned_u64 to achieve consistent behavior > in kernel<->userspace ABIs. > > There are structs in that can trivially be updated > to __aligned_u64 because the struct sizes are multiples of 8 bytes. > There is no change in memory layout on any CPU architecture and > therefore this change is safe. > > The commits that follow this one handle the trickier cases where > explanation about ABI breakage is necessary. > > Suggested-by: Jason Gunthorpe > Signed-off-by: Stefan Hajnoczi > --- > include/uapi/linux/vfio.h | 16 ++++++++-------- > 1 file changed, 8 insertions(+), 8 deletions(-) Reviewed-by: Jason Gunthorpe Jason