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[23.128.96.18]) by mx.google.com with ESMTP id i10si2059647eja.308.2021.02.10.13.15.56; Wed, 10 Feb 2021 13:16:20 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=rPvutsHI; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233273AbhBJVPR (ORCPT + 99 others); Wed, 10 Feb 2021 16:15:17 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44024 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233646AbhBJVNz (ORCPT ); Wed, 10 Feb 2021 16:13:55 -0500 Received: from mail-pg1-x52d.google.com (mail-pg1-x52d.google.com [IPv6:2607:f8b0:4864:20::52d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EE06BC061756 for ; Wed, 10 Feb 2021 13:13:14 -0800 (PST) Received: by mail-pg1-x52d.google.com with SMTP id o21so2055102pgn.12 for ; Wed, 10 Feb 2021 13:13:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=d2q16jUlTFF+PgCEeQltVe2F+f6bF9tkUCQkjupb9s0=; b=rPvutsHIjPqDhDGHVJxc/wM5v7CXDtz6AAMW3V7N0WFLbcXp6VlPvu2+MuYojMLpu6 GIM+7Cy5mjsqo+ICRC7VnG2x51YmptvQXPyPrl7hhAwbs8+Syc01kUyEuKHQy2xODowj 4uNefQtC8cqbHjMEd99RGKqCK9x0frcN2G1H2KCct+NI2QxkRqKoeblxVWK4wnmFXuH9 lR34nHkyF7KBoxhgHidVyqe4QOqy6qH/76EIM3dmZdaepccL+TUKbvmHW94HM9zZrz3w Z/EcBwAAiQgkZmdkpX5PUz5rw4h75HtAtgIpd+/TF+5MespBcPmDjg1ipd6NASc1bmFv JWtA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=d2q16jUlTFF+PgCEeQltVe2F+f6bF9tkUCQkjupb9s0=; b=Xkle6D7DwbBTtBdpfwH9pSAxgrpacekNn2CbgZvtebVY0SlVbPCY4Yj9mNF1/6XZrW NhLI70LsTLbgytXX5XVT/MSp5v7A9HDW6M4jDQMyf1BxY/sxxClYdQSSGhxhfShm1lsN wc8N5eX8NCr7An2zomr7oTXyoaq0cNqgTWJbJPc+hrynngsuEI6HUMyEMuZARpIb/8Bn 6LmA/aVT+G7vQh5p9ASBpZ9eGvPOu/6gwIcq0ILOypfKBiIWJEsil1YSZPS8cQB0v3Ar GkTgBEE2e0920u2v2c6iI6MpO5/UhAwpuesW9RdG5F8eOVye5N0fVtu2MuVlbUJHsG67 HuQA== X-Gm-Message-State: AOAM533oHZo/z6tf6/s6o8EPZ4xPt4SEiXnj0FoJhpJJNrBety/C9wn2 8/idbvWfeR/myOKFLLLa2+Tukg== X-Received: by 2002:a63:5d59:: with SMTP id o25mr4757081pgm.322.1612991594307; Wed, 10 Feb 2021 13:13:14 -0800 (PST) Received: from google.com ([2620:15c:f:10:11fc:33d:bf1:4cb8]) by smtp.gmail.com with ESMTPSA id y67sm3278585pfb.71.2021.02.10.13.13.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 Feb 2021 13:13:13 -0800 (PST) Date: Wed, 10 Feb 2021 13:13:07 -0800 From: Sean Christopherson To: "Woodhouse, David" Cc: "pbonzini@redhat.com" , "jmattson@google.com" , "joro@8bytes.org" , "kvm@vger.kernel.org" , "vkuznets@redhat.com" , "linux-kernel@vger.kernel.org" , "wanpengli@tencent.com" Subject: Re: [PATCH 5/5] KVM: x86/xen: Explicitly pad struct compat_vcpu_info to 64 bytes Message-ID: References: <20210210182609.435200-1-seanjc@google.com> <20210210182609.435200-6-seanjc@google.com> <8752a59b694671d25308d644cba661c4ec128094.camel@amazon.co.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8752a59b694671d25308d644cba661c4ec128094.camel@amazon.co.uk> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 10, 2021, Woodhouse, David wrote: > On Wed, 2021-02-10 at 10:26 -0800, Sean Christopherson wrote: > So it isn't clear the additionally padding really buys us anything; if > we play this game without knowing the ABI we'd be screwed anyway. But > it doesn't hurt. Ya, this is purely for folks reading the code and wondering how 62==64.