From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 96F024594A for ; Wed, 23 Oct 2024 04:03:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729656200; cv=none; b=VdXc5MTODlvsQ49wo1cv9BHvd1NhT8BFq3VcvrpodDnVj8imNJ7ndl+dGH2zSkXX7kq4iFiI3iygMxLbqFbj/iDEtVdhKF7aukzzp72dqIb30OkAbmZsX55wneN06MuNs27abqfWBiSeEgXsHudx3NwwW0pm9HpkZVdP7BxJZPM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729656200; c=relaxed/simple; bh=60FYQnwEjbn8ia2ijE+rJft1/gH3fGagogxsbRnBaRg=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=fxDYAWIpOq23FolNNC/cYQe1nJexxjFeUbaLRBv6c66LjLtZKIStBdD7Gby13Br+eFYkuTz7Mzeb27v1JfK8A/anIgdVZfm4Tmdy6t8OheHVKzQzPu0GjdUmr9ToJsBxxwAXtcjKdfFA8a9nm50VhrCIvJmTQ/VRdwqxUf9Ucv0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=E35sBhFN; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="E35sBhFN" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1729656196; 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; bh=fE9bH6h+Dp9Cy+4YV9E9TS1/FxNq1rWMOHkDfIVYSY8=; b=E35sBhFNluHaVqqslSsWGZAelY2X4PvAlSJAL4cobvkWeBfxwQHWEkrucZjlJeLDa7KPuE 0g7DnLb5qTn1umLEozDDbXHEkYCjCcu2mAPbtz1vY1Hch+JjjaLFQHnUvwElrYmbmYTWh+ h1rhDGqs2En71mSU5c0ePNll0A2f2tU= Received: from mail-pj1-f70.google.com (mail-pj1-f70.google.com [209.85.216.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-163-riQ5KrhtMkW4gx76AreTDA-1; Wed, 23 Oct 2024 00:03:13 -0400 X-MC-Unique: riQ5KrhtMkW4gx76AreTDA-1 Received: by mail-pj1-f70.google.com with SMTP id 98e67ed59e1d1-2e3b9fc918fso7647564a91.2 for ; Tue, 22 Oct 2024 21:03:13 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1729656193; x=1730260993; h=content-transfer-encoding:in-reply-to:from:content-language :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=fE9bH6h+Dp9Cy+4YV9E9TS1/FxNq1rWMOHkDfIVYSY8=; b=G+cwPxdRqazKj1GdxRvG4G36qrPaPYMgoyea7yXN4lKNE9VEJHBU3Hcr0ELr5aqohj ZNyUGpZz6MLpgY3EqDULk/eF340p9FeJBW2wT2+Y0dx0SHOD5hBF67ljq6fj4tY/Q0aU SSYraPmyMNPhQJDsviBY5q4fycE7Drytj0Qoj26b9LdwsLgBHn3GRss9XsQGZAUK4NMQ tCETeO81lK/OJdr1loerlCzaaK4a04OXhTeKWhP3ujcmvukuZ+CCCnyuhdZUgQjGQODD NbiMGILSbeuo4reBU7wGA6KfRGkn7eaIpaL1vaxdc/6Mc6A38V9G0072sriiG2Gn8Dec dSUg== X-Forwarded-Encrypted: i=1; AJvYcCVXavQiDquedOgiEFY4fVMstRV+JgVTcZJmHwgXjk6WqgEp3T5DSUPHw1OunJ1xuhBZqK/LLwDbxLRjsvM=@vger.kernel.org X-Gm-Message-State: AOJu0YxOUvlb55mJIBWVpl+1nx+yJFXTIuunkc4fpiswo9auY/IEeqM4 xVemkfmAfsQDl7t5ztVYzFxUueRA5nAcz88fwAqgDfT4AiEyC/wT61EB0tWEPyks7oxu9n79AyN 5DgkXd5deIX3NUo+DGOXqrEOqj21RGjPbIXJjfPegcvkpQ3x9v2nrofwLS0hscg== X-Received: by 2002:a17:90b:4c4b:b0:2e2:e148:3d30 with SMTP id 98e67ed59e1d1-2e76b60d401mr1665037a91.23.1729656192763; Tue, 22 Oct 2024 21:03:12 -0700 (PDT) X-Google-Smtp-Source: AGHT+IF7Nzd7b22QkSrSkT2X54oW0FrLiZkrnYmJFDKn3Ga/iSi3gYtHtDYeZYfv+zNxnl5T9y8tvQ== X-Received: by 2002:a17:90b:4c4b:b0:2e2:e148:3d30 with SMTP id 98e67ed59e1d1-2e76b60d401mr1664999a91.23.1729656192357; Tue, 22 Oct 2024 21:03:12 -0700 (PDT) Received: from [192.168.68.54] ([180.233.125.129]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-2e76e088f1fsm273930a91.56.2024.10.22.21.03.05 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 22 Oct 2024 21:03:11 -0700 (PDT) Message-ID: <032d29e7-b6a3-4493-833b-a9b6d9496a75@redhat.com> Date: Wed, 23 Oct 2024 14:03:03 +1000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 02/43] kvm: arm64: pgtable: Track the number of pages in the entry level To: Steven Price , kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: Suzuki K Poulose , Catalin Marinas , Marc Zyngier , Will Deacon , James Morse , Oliver Upton , Zenghui Yu , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Joey Gouly , Alexandru Elisei , Christoffer Dall , Fuad Tabba , linux-coco@lists.linux.dev, Ganapatrao Kulkarni , Shanker Donthineni , Alper Gun , "Aneesh Kumar K . V" References: <20241004152804.72508-1-steven.price@arm.com> <20241004152804.72508-3-steven.price@arm.com> Content-Language: en-US From: Gavin Shan In-Reply-To: <20241004152804.72508-3-steven.price@arm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/5/24 1:27 AM, Steven Price wrote: > From: Suzuki K Poulose > > Keep track of the number of pages allocated for the top level PGD, > rather than computing it every time (though we need it only twice now). > This will be used later by Arm CCA KVM changes. > > Signed-off-by: Suzuki K Poulose > Signed-off-by: Steven Price > --- > arch/arm64/include/asm/kvm_pgtable.h | 2 ++ > arch/arm64/kvm/hyp/pgtable.c | 5 +++-- > 2 files changed, 5 insertions(+), 2 deletions(-) > If we really want to have the number of pages for the top level PGDs, the existing helpers kvm_pgtable_stage2_pgd_size() for the same purpose needs to replaced by (struct kvm_pgtable::pgd_pages << PAGE_SHIFT) and then removed. The alternative would be just to use kvm_pgtable_stage2_pgd_size() instead of introducing struct kvm_pgtable::pgd_pages, which will be used in the slow paths where realm is created or destroyed. > diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h > index 03f4c3d7839c..25b512756200 100644 > --- a/arch/arm64/include/asm/kvm_pgtable.h > +++ b/arch/arm64/include/asm/kvm_pgtable.h > @@ -404,6 +404,7 @@ static inline bool kvm_pgtable_walk_lock_held(void) > * struct kvm_pgtable - KVM page-table. > * @ia_bits: Maximum input address size, in bits. > * @start_level: Level at which the page-table walk starts. > + * @pgd_pages: Number of pages in the entry level of the page-table. > * @pgd: Pointer to the first top-level entry of the page-table. > * @mm_ops: Memory management callbacks. > * @mmu: Stage-2 KVM MMU struct. Unused for stage-1 page-tables. > @@ -414,6 +415,7 @@ static inline bool kvm_pgtable_walk_lock_held(void) > struct kvm_pgtable { > u32 ia_bits; > s8 start_level; > + u8 pgd_pages; > kvm_pteref_t pgd; > struct kvm_pgtable_mm_ops *mm_ops; > > diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c > index b11bcebac908..9e1be28c3dc9 100644 > --- a/arch/arm64/kvm/hyp/pgtable.c > +++ b/arch/arm64/kvm/hyp/pgtable.c > @@ -1534,7 +1534,8 @@ int __kvm_pgtable_stage2_init(struct kvm_pgtable *pgt, struct kvm_s2_mmu *mmu, > u32 sl0 = FIELD_GET(VTCR_EL2_SL0_MASK, vtcr); > s8 start_level = VTCR_EL2_TGRAN_SL0_BASE - sl0; > > - pgd_sz = kvm_pgd_pages(ia_bits, start_level) * PAGE_SIZE; > + pgt->pgd_pages = kvm_pgd_pages(ia_bits, start_level); > + pgd_sz = pgt->pgd_pages * PAGE_SIZE; > pgt->pgd = (kvm_pteref_t)mm_ops->zalloc_pages_exact(pgd_sz); > if (!pgt->pgd) > return -ENOMEM; > @@ -1586,7 +1587,7 @@ void kvm_pgtable_stage2_destroy(struct kvm_pgtable *pgt) > }; > > WARN_ON(kvm_pgtable_walk(pgt, 0, BIT(pgt->ia_bits), &walker)); > - pgd_sz = kvm_pgd_pages(pgt->ia_bits, pgt->start_level) * PAGE_SIZE; > + pgd_sz = pgt->pgd_pages * PAGE_SIZE; > pgt->mm_ops->free_pages_exact(kvm_dereference_pteref(&walker, pgt->pgd), pgd_sz); > pgt->pgd = NULL; > } Thanks, Gavin