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 60E5EC001E0 for ; Mon, 23 Oct 2023 16:21:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233501AbjJWQVA (ORCPT ); Mon, 23 Oct 2023 12:21:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60092 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229544AbjJWQU6 (ORCPT ); Mon, 23 Oct 2023 12:20:58 -0400 Received: from mail-pl1-x64a.google.com (mail-pl1-x64a.google.com [IPv6:2607:f8b0:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 09C19103 for ; Mon, 23 Oct 2023 09:20:57 -0700 (PDT) Received: by mail-pl1-x64a.google.com with SMTP id d9443c01a7336-1cbe08af374so2044385ad.3 for ; Mon, 23 Oct 2023 09:20:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1698078056; x=1698682856; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=Q6M5Qcu8/m7OmULF94b0ZtR8TUikaFRq5dVXXqiKXwE=; b=VsPR9Aa7h9wJMuKyJLL0Rrk7gSaJd4M0k/q8KjPP6SGHXf+bEtIbH9h5d9z7USI4tK VTBC/bwSa176KERuEeEtnJFzYqcbvDFVGkmmFyDULik+30g6E2oz2+RMwax9KCxtJLDc JhjH+bDrjSKs8fpDiMj3vT8KW7c/l3T7r+pL5v6xo7zeGgkFL1bBC5l2+8QFhzoKpH0Y pUGV1r7ngWc3HRF1gV1zz2uJZ4vQ9SgmQnjFthTHJIw6PqVmEkNw0zyL7E83hvHjpv6Y 7hTp4cOR/AtwApc3hnr9Sic9uX8oEZ3aOqDUSeDLp8Wlzo9L2qwG6M1o7Ap22ioznSoS EBmg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1698078056; x=1698682856; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=Q6M5Qcu8/m7OmULF94b0ZtR8TUikaFRq5dVXXqiKXwE=; b=W0xd3nClbbT3Ig15e+85HWhhRGcBXtzRlbKriaKlXy9G3fzzWqHKYfFyR0APgGoyET lG+S2Y6zRsCCGMnDA2+vKRK1kQGS6tyuacHx86zpOsKqeGzXwnt7jdqEYAXY4sWW9OoD LW89EHQ5zAMSkuh6wFRVekoE9LX4kNYRHXnZozZDL8qrctWLvBKpR0dzVVscMHwWUpYQ l2CTx9ElRUBnvgCKgoRyKGKLGO9+btxD22rJHI1bSQk1uP3e8peAMgVKQej9XBk+5+Rc Rh9g3N9M3S0RyFDwlnUWTe65PGM30H2DLWNae+CRjxqxW26rHVGdiVKsOQ97+U3UFysl wF1g== X-Gm-Message-State: AOJu0Yzt47/VN+RVD9k8RCQp0dbFzQInRivRWteAvV7lTfnIIaRWauM1 bq7b41m/2dPx+sQrXQN3fNeSiJ3Eh1M= X-Google-Smtp-Source: AGHT+IE9RhMoOLSJBVIJXK/i7kHEGZvfdQgmWbkxVDAbHyWfkKuY1/wHnvUHmuSIonljHFPKy/AX6Q3ht4s= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a17:903:23cc:b0:1ca:4d35:b2f9 with SMTP id o12-20020a17090323cc00b001ca4d35b2f9mr176090plh.8.1698078056416; Mon, 23 Oct 2023 09:20:56 -0700 (PDT) Date: Mon, 23 Oct 2023 09:20:54 -0700 In-Reply-To: <20230913124227.12574-3-binbin.wu@linux.intel.com> Mime-Version: 1.0 References: <20230913124227.12574-1-binbin.wu@linux.intel.com> <20230913124227.12574-3-binbin.wu@linux.intel.com> Message-ID: Subject: Re: [PATCH v11 02/16] KVM: x86: Use a new flag for branch targets From: Sean Christopherson To: Binbin Wu Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, pbonzini@redhat.com, chao.gao@intel.com, kai.huang@intel.com, David.Laight@aculab.com, robert.hu@linux.intel.com, guang.zeng@intel.com Content-Type: text/plain; charset="us-ascii" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Wed, Sep 13, 2023, Binbin Wu wrote: > Use the new flag X86EMUL_F_BRANCH instead of X86EMUL_F_FETCH in assign_eip() > to distinguish instruction fetch and branch target computation for features > that handle differently on them, e.g. Linear Address Space Separation (LASS). A slightly different shortlog+changelog: KVM: x86: Add an emulator flag to differntiate branch targets from fetches Add an emulator flag, X86EMUL_F_BRANCH, and use it instead of X86EMUL_F_FETCH in assign_eip() to distinguish between instruction fetch and branch target computation for features that handle them differently, e.g. Intel's upcoming Linear Address Space Separation (LASS) applies to code fetches but not branch target calculations. The shortlog in particular is far too vague. > As of this patch, X86EMUL_F_BRANCH and X86EMUL_F_FETCH are identical as far > as KVM is concerned. This patch looks good, but I'm going to skip it for now as it's not needed until LASS is supported, since LAM doesn't differentiate between the two. I.e. this should have been the first patch in the LASS portion of the series. No need to repost, it's trivially easy to tweak vmx_get_untagged_addr().