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 1795BC7618E for ; Mon, 24 Apr 2023 15:51:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231932AbjDXPvy (ORCPT ); Mon, 24 Apr 2023 11:51:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54144 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230500AbjDXPvw (ORCPT ); Mon, 24 Apr 2023 11:51:52 -0400 Received: from mail-pj1-x1049.google.com (mail-pj1-x1049.google.com [IPv6:2607:f8b0:4864:20::1049]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 67A75114 for ; Mon, 24 Apr 2023 08:51:50 -0700 (PDT) Received: by mail-pj1-x1049.google.com with SMTP id 98e67ed59e1d1-2473f8329f7so4578672a91.1 for ; Mon, 24 Apr 2023 08:51:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1682351510; x=1684943510; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=jtSUeuCkwFR5o9I94yYcCoz20ACvzd68ye5sBnm4VyI=; b=H1ijR7UE/3KIVe/zpESfqf8ex9Yh+rK/GGtg6nGEheB0BmipgBSBTp7H6p2VnibeMd H0iWfBu7ZV24ETrjrSSNaNavlJOjqTR9RIx281EJZej6/mlOcy3Wmtz038RtymvYqmmw rZPl5BNouEtiW4Xq8kqyRr2HSeNV2IA286Rtta5JkRlDMHoeTyE8WynK8TaSs1wYMLPn fjO3wScNWdGBu6Yno8qNZPc9cWhDU+tJoGTAO7v6GCZYj+Aq7qA95KhqUcqSHLXidx4H IUs/RqX80xXkdkaqTd+vX0H3Q2MkhExajcheg9Nn2td+mUPlKpc/OezTlJK3tFY2tl+D zKhQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1682351510; x=1684943510; 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=jtSUeuCkwFR5o9I94yYcCoz20ACvzd68ye5sBnm4VyI=; b=c94rfN99F9e0KJBTwSmHKMwdQJyv3zLjccC03RKkZCwtTkNs7dHz6NWJRqO4rkGP58 iGAr+n4tTLMKO6diHOBQQ3POonQ9/rZeEzllAdKV4Ru3vVM4ieudyc1bwPRH29EBINwa AIA8VeyJJcgEfzCCc60Xli7A1YXYCEMcPMqAY7ObaB35ec1XoBSoJ0MGWw+sx1/P8Y6k v4Jp3rRMHbks7BXj1V7kU2j9cM4CsEPkSN5WesNfC+pjrCPiO08FSGtC6klztCaNf17G dQYqWhAIYsq/2iZSdIQ21qV5EZpeNaJP1gtmAXC7lhbwFpW7qdSWJ6USLJd3zdQGMPdI Lxnw== X-Gm-Message-State: AAQBX9eSFWcKG/eT9Y2o0/fRFHqfZly+Y50TimxOB7ukdrFwwWD+sl0l EYOEcfwQFCyj/exIQugUxm5u0Ul8kyk= X-Google-Smtp-Source: AKy350bbdh+Ihp0N09viUjEVVR+Tbs0JLwUQngZeZz2fNHKtuBjHMV6nOn75eC0gw6MmjsvH87TBadNjEm4= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a17:90a:410d:b0:246:a74f:fd73 with SMTP id u13-20020a17090a410d00b00246a74ffd73mr3408751pjf.6.1682351509797; Mon, 24 Apr 2023 08:51:49 -0700 (PDT) Date: Mon, 24 Apr 2023 08:51:48 -0700 In-Reply-To: <20230422111834.00003689@gmail.com> Mime-Version: 1.0 References: <23cc6df6ec2ca776c3efe148e70ba290aa3de319.1678643052.git.isaku.yamahata@intel.com> <20230422111834.00003689@gmail.com> Message-ID: Subject: Re: [PATCH v13 048/113] KVM: x86/mmu: Disallow dirty logging for x86 TDX From: Sean Christopherson To: Zhi Wang Cc: isaku.yamahata@intel.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, isaku.yamahata@gmail.com, Paolo Bonzini , erdemaktas@google.com, Sagi Shahar , David Matlack , Kai Huang , Sean Christopherson , Michael Roth Content-Type: text/plain; charset="us-ascii" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Sat, Apr 22, 2023, Zhi Wang wrote: > On Sun, 12 Mar 2023 10:56:12 -0700 > isaku.yamahata@intel.com wrote: > > > From: Isaku Yamahata > > > > TDX doesn't support dirty logging. Report dirty logging isn't supported so > > that device model, for example qemu, can properly handle it. Silently > > ignore on dirty logging on private GFNs of TDX. ... > > +bool kvm_arch_dirty_log_supported(struct kvm *kvm) > > +{ > > + return kvm->arch.vm_type != KVM_X86_PROTECTED_VM; > > +} > > + > > Maybe introduce a new x86 ops for SNP/TDX to check this separately as SNP > might still support it? With the current approach, I think both SNP/TDX > will be affected. So does the later patch about page-tracking. This patch is unnecessary, the plan is to disallow dirty logging on memslots that support private mapping, e.g. we'll end up with something like this: static int check_memory_region_flags(struct kvm *kvm, const struct kvm_userspace_memory_region2 *mem) { u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES; if (kvm_arch_has_private_mem(kvm)) valid_flags |= KVM_MEM_PRIVATE; /* Dirty logging private memory is not currently supported. */ if (mem->flags & KVM_MEM_PRIVATE) valid_flags &= ~KVM_MEM_LOG_DIRTY_PAGES; #ifdef __KVM_HAVE_READONLY_MEM valid_flags |= KVM_MEM_READONLY; #endif if (mem->flags & ~valid_flags) return -EINVAL; return 0; } > Michael, can you confirm this? No need to confirm (or deny) at this point, enabling dirty logging for private memory is not something I want to merge in the initial TDX/SNP series, regardless of whether or not it's supported by "hardware", a.k.a. trusted firmware.