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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8B565CD1288 for ; Sat, 30 Mar 2024 21:35:45 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 1DA176B0092; Sat, 30 Mar 2024 17:35:45 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1B10E6B0093; Sat, 30 Mar 2024 17:35:45 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 02B066B0095; Sat, 30 Mar 2024 17:35:44 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id D7CAB6B0092 for ; Sat, 30 Mar 2024 17:35:44 -0400 (EDT) Received: from smtpin30.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 8C1A1803C9 for ; Sat, 30 Mar 2024 21:35:44 +0000 (UTC) X-FDA: 81955012608.30.1183F2B Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf08.hostedemail.com (Postfix) with ESMTP id 50DCC16000C for ; Sat, 30 Mar 2024 21:35:42 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=JSkQ4rEh; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf08.hostedemail.com: domain of pbonzini@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=pbonzini@redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1711834542; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=k6nhJ/n2fVMLTJ5orSzZrSN05UZkFdn1WgbErq3l2Pk=; b=n42j4cNVbsLHzP2glG8t1IUlFG3lQJZxePjSMe8xa3NOM0mFwz/IghPq1lvyzlGNNWGbyM EnW0pXPoulNXx+yKyiNSjfSYjWBp61O7I6qBAR9qXQt1vcElXPkKuj58Hh5uQ+lsOn9hRa gC8sVldk3rwn47NayUp9t5k0BE2csWk= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=JSkQ4rEh; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf08.hostedemail.com: domain of pbonzini@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=pbonzini@redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1711834542; a=rsa-sha256; cv=none; b=rwcK1CwFtlg9Mnw/KWbOi4ocqehFxxTEw+59Ifon6OIT5p88lPrjU/Ktl6Q55suJSz7BDq zYEYGa70tsBkHxDm06TrNzk1GgZ5Bwevi+bMwsmWLeZuefxPaR6XL3LslJyllGTvAtziJg vddxBaSWy96bCRZo9pcca3SnRkAevzA= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1711834541; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=k6nhJ/n2fVMLTJ5orSzZrSN05UZkFdn1WgbErq3l2Pk=; b=JSkQ4rEhAmsVeZHuSYL5XgrgNAt13SHnq30WYpbBo6nFSIhiqf0vtKADsEKaBU6OpGVLpQ QDX2PzilH9CaTqvHEj9l8ryQdEGf/Tgw6oCc+JpP/bBlFa90eiL40fMPrYKiSpY28VeuVr I/R0WttkS5b3uVoyvz/AgBrsOKNpSuI= Received: from mail-lf1-f70.google.com (mail-lf1-f70.google.com [209.85.167.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-110-k2zpApkeMOurZFw1rwvJUg-1; Sat, 30 Mar 2024 17:35:39 -0400 X-MC-Unique: k2zpApkeMOurZFw1rwvJUg-1 Received: by mail-lf1-f70.google.com with SMTP id 2adb3069b0e04-515d1395657so1135119e87.1 for ; Sat, 30 Mar 2024 14:35:39 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1711834538; x=1712439338; h=content-transfer-encoding:in-reply-to:autocrypt:content-language :from:references:cc:to:subject:user-agent:mime-version:date :message-id:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=k6nhJ/n2fVMLTJ5orSzZrSN05UZkFdn1WgbErq3l2Pk=; b=tq1jTrP4aKTVEOv3QqAuVbAGwzFz4rBK71qfwSBLDUh2/ydAg8NartANvqHviebzpL F/AFp5JTJQ+RthtlHJkC7FJs25TMFXYkvfS4btz9Aa2s9sy54uND0wA2TQQHA9wFihNP Mf5x3Pmx1n3PsDSljCHLv7Eqx2MS1E8TxEtcxukloVnzg590twzEYm+iBeTqzomfLz0u pm65ZGpNoB8xhR0ULG9Bl5jQGzFk29riRbgskAa7c6Wf8oofLvFEGKN6vAAspzT8fOwh lZo5gRLmCTAkn5xtuQc66HRE1x88ghV7trRENzmrbL+qkTH3f+t4KsvEh4/uHVk777Cm 9N8A== X-Forwarded-Encrypted: i=1; AJvYcCXb+CjLlKWiMPG6y18m/BWWQCoONhofAMzZYcm1I7f5MDd1BKqPS974+tE+vokSecqdOsbonNN8LZSR/evAZXghAmc= X-Gm-Message-State: AOJu0YzPiUACDjewjmF+bycYY45HYBBKaW/ZniyLE4KP8YOfwMdIyMwd d+zZie/Yr1CZ+wAgmIaK1XysHLebZz0Qt91J2Zy9uwO3ZqKS8eZjTBlPRtjjChxZGmSIdNoa7OW WLRK7tvgBBtwpIQ3DlEZDeasLYKqK+KbgyiKtFoo441j/zxg0 X-Received: by 2002:a19:2d18:0:b0:513:b062:98c4 with SMTP id k24-20020a192d18000000b00513b06298c4mr3643256lfj.11.1711834538175; Sat, 30 Mar 2024 14:35:38 -0700 (PDT) X-Google-Smtp-Source: AGHT+IH5PGmEGHf24nUfF7B7vuwJRBVN0rKW1MZiU9RQdC6MVZb3TnEUgyIIaZghldmm9GaQfOSwZw== X-Received: by 2002:a19:2d18:0:b0:513:b062:98c4 with SMTP id k24-20020a192d18000000b00513b06298c4mr3643226lfj.11.1711834537752; Sat, 30 Mar 2024 14:35:37 -0700 (PDT) Received: from [192.168.10.4] ([151.95.49.219]) by smtp.googlemail.com with ESMTPSA id w4-20020a1709062f8400b00a4e07f8b6bfsm3445434eji.59.2024.03.30.14.35.34 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 30 Mar 2024 14:35:37 -0700 (PDT) Message-ID: <00800f4b-5403-4416-b984-12b207362a19@redhat.com> Date: Sat, 30 Mar 2024 22:35:33 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v12 24/29] KVM: SEV: Avoid WBINVD for HVA-based MMU notifications for SNP To: Michael Roth , kvm@vger.kernel.org Cc: linux-coco@lists.linux.dev, linux-mm@kvack.org, linux-crypto@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, jroedel@suse.de, thomas.lendacky@amd.com, hpa@zytor.com, ardb@kernel.org, seanjc@google.com, vkuznets@redhat.com, jmattson@google.com, luto@kernel.org, dave.hansen@linux.intel.com, slp@redhat.com, pgonda@google.com, peterz@infradead.org, srinivas.pandruvada@linux.intel.com, rientjes@google.com, dovmurik@linux.ibm.com, tobin@ibm.com, bp@alien8.de, vbabka@suse.cz, kirill@shutemov.name, ak@linux.intel.com, tony.luck@intel.com, sathyanarayanan.kuppuswamy@linux.intel.com, alpergun@google.com, jarkko@kernel.org, ashish.kalra@amd.com, nikunj.dadhania@amd.com, pankaj.gupta@amd.com, liam.merwick@oracle.com References: <20240329225835.400662-1-michael.roth@amd.com> <20240329225835.400662-25-michael.roth@amd.com> From: Paolo Bonzini Autocrypt: addr=pbonzini@redhat.com; keydata= xsEhBFRCcBIBDqDGsz4K0zZun3jh+U6Z9wNGLKQ0kSFyjN38gMqU1SfP+TUNQepFHb/Gc0E2 CxXPkIBTvYY+ZPkoTh5xF9oS1jqI8iRLzouzF8yXs3QjQIZ2SfuCxSVwlV65jotcjD2FTN04 hVopm9llFijNZpVIOGUTqzM4U55sdsCcZUluWM6x4HSOdw5F5Utxfp1wOjD/v92Lrax0hjiX DResHSt48q+8FrZzY+AUbkUS+Jm34qjswdrgsC5uxeVcLkBgWLmov2kMaMROT0YmFY6A3m1S P/kXmHDXxhe23gKb3dgwxUTpENDBGcfEzrzilWueOeUWiOcWuFOed/C3SyijBx3Av/lbCsHU Vx6pMycNTdzU1BuAroB+Y3mNEuW56Yd44jlInzG2UOwt9XjjdKkJZ1g0P9dwptwLEgTEd3Fo UdhAQyRXGYO8oROiuh+RZ1lXp6AQ4ZjoyH8WLfTLf5g1EKCTc4C1sy1vQSdzIRu3rBIjAvnC tGZADei1IExLqB3uzXKzZ1BZ+Z8hnt2og9hb7H0y8diYfEk2w3R7wEr+Ehk5NQsT2MPI2QBd wEv1/Aj1DgUHZAHzG1QN9S8wNWQ6K9DqHZTBnI1hUlkp22zCSHK/6FwUCuYp1zcAEQEAAc0j UGFvbG8gQm9uemluaSA8cGJvbnppbmlAcmVkaGF0LmNvbT7CwU0EEwECACMFAlRCcBICGwMH CwkIBwMCAQYVCAIJCgsEFgIDAQIeAQIXgAAKCRB+FRAMzTZpsbceDp9IIN6BIA0Ol7MoB15E 11kRz/ewzryFY54tQlMnd4xxfH8MTQ/mm9I482YoSwPMdcWFAKnUX6Yo30tbLiNB8hzaHeRj jx12K+ptqYbg+cevgOtbLAlL9kNgLLcsGqC2829jBCUTVeMSZDrzS97ole/YEez2qFpPnTV0 VrRWClWVfYh+JfzpXmgyhbkuwUxNFk421s4Ajp3d8nPPFUGgBG5HOxzkAm7xb1cjAuJ+oi/K CHfkuN+fLZl/u3E/fw7vvOESApLU5o0icVXeakfSz0LsygEnekDbxPnE5af/9FEkXJD5EoYG SEahaEtgNrR4qsyxyAGYgZlS70vkSSYJ+iT2rrwEiDlo31MzRo6Ba2FfHBSJ7lcYdPT7bbk9 AO3hlNMhNdUhoQv7M5HsnqZ6unvSHOKmReNaS9egAGdRN0/GPDWr9wroyJ65ZNQsHl9nXBqE AukZNr5oJO5vxrYiAuuTSd6UI/xFkjtkzltG3mw5ao2bBpk/V/YuePrJsnPFHG7NhizrxttB nTuOSCMo45pfHQ+XYd5K1+Cv/NzZFNWscm5htJ0HznY+oOsZvHTyGz3v91pn51dkRYN0otqr bQ4tlFFuVjArBZcapSIe6NV8C4cEiSTOwE0EVEJx7gEIAMeHcVzuv2bp9HlWDp6+RkZe+vtl KwAHplb/WH59j2wyG8V6i33+6MlSSJMOFnYUCCL77bucx9uImI5nX24PIlqT+zasVEEVGSRF m8dgkcJDB7Tps0IkNrUi4yof3B3shR+vMY3i3Ip0e41zKx0CvlAhMOo6otaHmcxr35sWq1Jk tLkbn3wG+fPQCVudJJECvVQ//UAthSSEklA50QtD2sBkmQ14ZryEyTHQ+E42K3j2IUmOLriF dNr9NvE1QGmGyIcbw2NIVEBOK/GWxkS5+dmxM2iD4Jdaf2nSn3jlHjEXoPwpMs0KZsgdU0pP JQzMUMwmB1wM8JxovFlPYrhNT9MAEQEAAcLBMwQYAQIACQUCVEJx7gIbDAAKCRB+FRAMzTZp sadRDqCctLmYICZu4GSnie4lKXl+HqlLanpVMOoFNnWs9oRP47MbE2wv8OaYh5pNR9VVgyhD OG0AU7oidG36OeUlrFDTfnPYYSF/mPCxHttosyt8O5kabxnIPv2URuAxDByz+iVbL+RjKaGM GDph56ZTswlx75nZVtIukqzLAQ5fa8OALSGum0cFi4ptZUOhDNz1onz61klD6z3MODi0sBZN Aj6guB2L/+2ZwElZEeRBERRd/uommlYuToAXfNRdUwrwl9gRMiA0WSyTb190zneRRDfpSK5d usXnM/O+kr3Dm+Ui+UioPf6wgbn3T0o6I5BhVhs4h4hWmIW7iNhPjX1iybXfmb1gAFfjtHfL xRUr64svXpyfJMScIQtBAm0ihWPltXkyITA92ngCmPdHa6M1hMh4RDX+Jf1fiWubzp1voAg0 JBrdmNZSQDz0iKmSrx8xkoXYfA3bgtFN8WJH2xgFL28XnqY4M6dLhJwV3z08tPSRqYFm4NMP dRsn0/7oymhneL8RthIvjDDQ5ktUjMe8LtHr70OZE/TT88qvEdhiIVUogHdo4qBrk41+gGQh b906Dudw5YhTJFU3nC6bbF2nrLlB4C/XSiH76ZvqzV0Z/cAMBo5NF/w= In-Reply-To: <20240329225835.400662-25-michael.roth@amd.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Stat-Signature: mkdp4srok759dayzoezij33bcpc5715r X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 50DCC16000C X-HE-Tag: 1711834542-206107 X-HE-Meta: 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 fU7ZWNmn 9YZjk0U5isbctKT2bAErp5AX1kKWbG3PRa+No5yi+QT9cacOKKLoKeVXFs3BXdvk2uZr/jkMY7zTQ5mqZ/HSErbB5rN1vzUDLW/ssORiESuGML/+Slsr7CdcnQ9MsfXbaB8quXNixOokjouArVJLSaUbXvSvJ79/bVp89vwCPaql4oU+ldm6w+/3hStDmUKPeDdl7iMwcfUnxvBfBZag7hNYjP/mO3kavPBLASAEs2NTPIQ7wb4mcVRlMV26Jy6HQUf7udwoYTQE0qE+zdig7uwXq4mxZs30dfjM8NMorQfnI8gMAOaD/cYRcU6M8qYw3YYlCcdxYEB3YJCzbq/1CSmLUzGjCGgLLM9ub9el3UsL/N8HniXPMH0+JWTVDGeQSfnx3gaOA0HHniAKQLTEGSbT3pXmGwPqthE/0YiSF4sXu8aGYtlj6PVmNsZsfTvIbUJF5 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 3/29/24 23:58, Michael Roth wrote: > From: Ashish Kalra > > With SNP/guest_memfd, private/encrypted memory should not be mappable, > and MMU notifications for HVA-mapped memory will only be relevant to > unencrypted guest memory. Therefore, the rationale behind issuing a > wbinvd_on_all_cpus() in sev_guest_memory_reclaimed() should not apply > for SNP guests and can be ignored. > > Signed-off-by: Ashish Kalra > [mdr: Add some clarifications in commit] > Signed-off-by: Michael Roth Reviewed-by: Paolo Bonzini > --- > arch/x86/kvm/svm/sev.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c > index 31f6f4786503..3e8de7cb3c89 100644 > --- a/arch/x86/kvm/svm/sev.c > +++ b/arch/x86/kvm/svm/sev.c > @@ -2975,7 +2975,14 @@ static void sev_flush_encrypted_page(struct kvm_vcpu *vcpu, void *va) > > void sev_guest_memory_reclaimed(struct kvm *kvm) > { > - if (!sev_guest(kvm)) > + /* > + * With SNP+gmem, private/encrypted memory should be > + * unreachable via the hva-based mmu notifiers. Additionally, > + * for shared->private translations, H/W coherency will ensure > + * first guest access to the page would clear out any existing > + * dirty copies of that cacheline. > + */ > + if (!sev_guest(kvm) || sev_snp_guest(kvm)) > return; > > wbinvd_on_all_cpus();