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 DD103C38142 for ; Wed, 24 Aug 2022 10:42:35 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 4D3946B0073; Wed, 24 Aug 2022 06:42:35 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 45C2D6B0074; Wed, 24 Aug 2022 06:42:35 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2D6C86B0075; Wed, 24 Aug 2022 06:42:35 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 184416B0073 for ; Wed, 24 Aug 2022 06:42:35 -0400 (EDT) Received: from smtpin22.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id CD8211A0246 for ; Wed, 24 Aug 2022 10:42:34 +0000 (UTC) X-FDA: 79834147428.22.1183A48 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by imf05.hostedemail.com (Postfix) with ESMTP id C392810000D for ; Wed, 24 Aug 2022 10:42:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1661337753; x=1692873753; h=date:from:to:cc:subject:message-id:reply-to:references: mime-version:in-reply-to; bh=lnG4/IetgJJiCFvYl2XSmHM42xhaifZaMgp7nfdirTE=; b=MMZ1CgNIzHY20rjGP+13CPsIS8lEYQu/cO2bpZqNz68YScr/mOalIzZ6 VToYgGoqsti83PHV3fHtDukjRBFXxnIWakLGKtZZ9sX1ufmwjyJs8hToV P1yKgWfiSvB6yot9oXR0aquqrxyG1zSpaZ2CQoHqmhVsorvCtcBnzXzB3 MwZxx5RXUBb2kz8+hjPnaFXTkKZX2HQxiqEG38TjK5k5A6oo8L3eWQi4I RTtDoyoXnwQwqs+57XRGStOgmFZNKLBH+ZGESZFFQyxaOc8MsBDcRYLXC 4oNjH1UZBK/NoQ6Wl/Gv26yJaxCERkJw0fmDZUyIx35c1r61SASDqp9mo Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10448"; a="280904801" X-IronPort-AV: E=Sophos;i="5.93,260,1654585200"; d="scan'208";a="280904801" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Aug 2022 03:42:32 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.93,260,1654585200"; d="scan'208";a="605989312" Received: from chaop.bj.intel.com (HELO localhost) ([10.240.193.75]) by orsmga007.jf.intel.com with ESMTP; 24 Aug 2022 03:42:21 -0700 Date: Wed, 24 Aug 2022 18:37:38 +0800 From: Chao Peng To: Vishal Annapurve Cc: kvm list , LKML , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, linux-doc@vger.kernel.org, qemu-devel@nongnu.org, linux-kselftest@vger.kernel.org, Paolo Bonzini , Jonathan Corbet , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86 , "H . Peter Anvin" , Hugh Dickins , Jeff Layton , "J . Bruce Fields" , Andrew Morton , Shuah Khan , Mike Rapoport , Steven Price , "Maciej S . Szmigiero" , Vlastimil Babka , Yu Zhang , "Kirill A . Shutemov" , Andy Lutomirski , Jun Nakajima , Dave Hansen , Andi Kleen , David Hildenbrand , aarcange@redhat.com, ddutile@redhat.com, dhildenb@redhat.com, Quentin Perret , Michael Roth , mhocko@suse.com, Muchun Song Subject: Re: [PATCH v7 11/14] KVM: Register/unregister the guest private memory regions Message-ID: <20220824103738.GA1386620@chaop.bj.intel.com> Reply-To: Chao Peng References: <20220706082016.2603916-1-chao.p.peng@linux.intel.com> <20220706082016.2603916-12-chao.p.peng@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1661337754; h=from:from:sender:reply-to: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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=hEzynOBdCUM00QDOnShjzfAaQHLPwKTzgcwT6X3Jc+8=; b=1vpZ+fqUwx0sGiZ9/sM6lOwFxiY4hE9t7PGvPhPIG4mc9B8MHQ5hXNYDfq+MeTLtGrHXDM +OvpaGGP44hd0RqfFEdPsen8p4UoTFtwdcpNbKJnlIHlseo0zVAF/bUdy93zNYQnL8jM2M mZzQ58+UVZQyGsUzVhi1/DefYnLE+NI= ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=MMZ1CgNI; spf=none (imf05.hostedemail.com: domain of chao.p.peng@linux.intel.com has no SPF policy when checking 134.134.136.20) smtp.mailfrom=chao.p.peng@linux.intel.com; dmarc=fail reason="No valid SPF" header.from=intel.com (policy=none) ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1661337754; a=rsa-sha256; cv=none; b=dNPymyHDEQxYM05kAB1Hs775KYy3IjEbVQ2YEzBkt30WStFYDH+KGhapbw6WEyBfn99B+S 75pUc3HZtkEdjUU13XMkn0dBkKOy/+9uDA/2HTfVcfRIJ89+is4gj8pgRQuQJXUQiaECb0 yVwfArNRal6CbV1wgptSo2mbzexAaH4= X-Stat-Signature: sbzq8mej86uhsockiwhmmcuhxr6o6na5 X-Rspamd-Queue-Id: C392810000D Authentication-Results: imf05.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=MMZ1CgNI; spf=none (imf05.hostedemail.com: domain of chao.p.peng@linux.intel.com has no SPF policy when checking 134.134.136.20) smtp.mailfrom=chao.p.peng@linux.intel.com; dmarc=fail reason="No valid SPF" header.from=intel.com (policy=none) X-Rspam-User: X-Rspamd-Server: rspam03 X-HE-Tag: 1661337753-648463 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: On Fri, Aug 19, 2022 at 12:37:42PM -0700, Vishal Annapurve wrote: > > ... > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > > index 230c8ff9659c..bb714c2a4b06 100644 > > --- a/virt/kvm/kvm_main.c > > +++ b/virt/kvm/kvm_main.c > > @@ -914,6 +914,35 @@ static int kvm_init_mmu_notifier(struct kvm *kvm) > > > > #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */ > > > > +#ifdef CONFIG_HAVE_KVM_PRIVATE_MEM > > +#define KVM_MEM_ATTR_PRIVATE 0x0001 > > +static int kvm_vm_ioctl_set_encrypted_region(struct kvm *kvm, unsigned int ioctl, > > + struct kvm_enc_region *region) > > +{ > > + unsigned long start, end; > > + void *entry; > > + int r; > > + > > + if (region->size == 0 || region->addr + region->size < region->addr) > > + return -EINVAL; > > + if (region->addr & (PAGE_SIZE - 1) || region->size & (PAGE_SIZE - 1)) > > + return -EINVAL; > > + > > + start = region->addr >> PAGE_SHIFT; > > + end = (region->addr + region->size - 1) >> PAGE_SHIFT; > > + > > + entry = ioctl == KVM_MEMORY_ENCRYPT_REG_REGION ? > > + xa_mk_value(KVM_MEM_ATTR_PRIVATE) : NULL; > > + > > + r = xa_err(xa_store_range(&kvm->mem_attr_array, start, end, > > + entry, GFP_KERNEL_ACCOUNT)); > > xa_store_range seems to create multi-index entries by default. > Subsequent xa_store_range call changes all the entries stored > previously. By using xa_store_range and storing them as multi-index entries I expected to save some memory for continuous pages originally. But sounds like the current multi-index store behaviour isn't quite ready for our usage. Chao > xa_store needs to be used here instead of xa_store_range to achieve > the intended behavior. > > > + > > + kvm_zap_gfn_range(kvm, start, end + 1); > > + > > + return r; > > +} > > +#endif /* CONFIG_HAVE_KVM_PRIVATE_MEM */ > > + > > ...