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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 87AD91061B02 for ; Mon, 30 Mar 2026 14:51:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=7S/JdnU/dGCZ5ndvfhZZdwAqxwTJujt9XEkHBO47ssU=; b=YuOW9qfsDbXuf6Z9aE4VTsTfw9 GroOfUx3miYTBZZDwEYVigPQPwYvhd9epiGdBvHKi0LtXEdbMJOtx5hErnUFVO071UBDwx3+F4Mdp huxiN63PbW5W6pMaGk851O7xbbdXgHaDxoIKjihyIF5BTHaWpAXgaYuIR1ElV0lm2Ow+M5HsCE3Ex tqpQ1BdWTV0qOf1kdGJExj8nEy3izQOmXTmSYZvjPhHg/JvM8pzZOyCOyuquik296+mq2gKf2L+Vd vPhz4JADkb4ureaPkHV9Uj/j+odLKxiJdx1HjVJ6uoHSyCMEv6wpgx9Bl+wIVK6JrFzpYoJ17ioB4 XpxeH+Sw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1w7DxX-0000000BUeW-2Rjq; Mon, 30 Mar 2026 14:51:19 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1w7DwR-0000000BTj8-2XNH for linux-arm-kernel@lists.infradead.org; Mon, 30 Mar 2026 14:50:11 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id EF29D60128; Mon, 30 Mar 2026 14:50:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CC85EC4CEF7; Mon, 30 Mar 2026 14:50:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774882210; bh=pFJJO55Bup4H+ayanSXWyht2AlYF5v4+8PnrdfjS8Vo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ROScp2Ysp1N8l7BQ++8jeB5hDCe3Bz1Q7okW9KOMs08CEPSBX5sOPpT4/0XTegRVN 1nWICvmEDhQcxwpingtqKUVJdt8HrpaTYp3IqVbvs0PEot3PRUfR3gIhMSmVEA0b9s zwMotBPY1MUBJACWVPFEr00v8gMonoqvlPJtspKXEGagNe8cgUekRKHgTYsZHDjco4 tn7B7LGP0eNjPkMGlFZzyhYNKUUdoPTI3v2hVd0Z+rL7mtIKcKpAFdyUc5eUCjIOze ohKRl+vezF/AOsb5TkF4XNl4lhnyJpwh+L+JtZsW7SUFo0kZQ7kra1hJmme6Xd/E67 lfR9zdLsZX71w== From: Will Deacon To: kvmarm@lists.linux.dev Cc: linux-arm-kernel@lists.infradead.org, Will Deacon , Marc Zyngier , Oliver Upton , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Quentin Perret , Fuad Tabba , Vincent Donnefort , Mostafa Saleh , Alexandru Elisei Subject: [PATCH v5 24/38] KVM: arm64: Annotate guest donations with handle and gfn in host stage-2 Date: Mon, 30 Mar 2026 15:48:25 +0100 Message-ID: <20260330144841.26181-25-will@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260330144841.26181-1-will@kernel.org> References: <20260330144841.26181-1-will@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Handling host kernel faults arising from accesses to donated guest memory will require an rmap-like mechanism to identify the guest mapping of the faulting page. Extend the page donation logic to encode the guest handle and gfn alongside the owner information in the host stage-2 pte. Reviewed-by: Fuad Tabba Tested-by: Fuad Tabba Tested-by: Mostafa Saleh Signed-off-by: Will Deacon --- arch/arm64/kvm/hyp/nvhe/mem_protect.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c index 90003cbf5603..51cb5c89fd20 100644 --- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c +++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c @@ -593,7 +593,6 @@ int host_stage2_set_owner_locked(phys_addr_t addr, u64 size, u8 owner_id) if (!ret) __host_update_page_state(addr, size, PKVM_PAGE_OWNED); break; - case PKVM_ID_GUEST: case PKVM_ID_HYP: ret = host_stage2_set_owner_metadata_locked(addr, size, owner_id, 0); @@ -603,6 +602,20 @@ int host_stage2_set_owner_locked(phys_addr_t addr, u64 size, u8 owner_id) return ret; } +#define KVM_HOST_PTE_OWNER_GUEST_HANDLE_MASK GENMASK(15, 0) +/* We need 40 bits for the GFN to cover a 52-bit IPA with 4k pages and LPA2 */ +#define KVM_HOST_PTE_OWNER_GUEST_GFN_MASK GENMASK(55, 16) +static u64 host_stage2_encode_gfn_meta(struct pkvm_hyp_vm *vm, u64 gfn) +{ + pkvm_handle_t handle = vm->kvm.arch.pkvm.handle; + + BUILD_BUG_ON((pkvm_handle_t)-1 > KVM_HOST_PTE_OWNER_GUEST_HANDLE_MASK); + WARN_ON(!FIELD_FIT(KVM_HOST_PTE_OWNER_GUEST_GFN_MASK, gfn)); + + return FIELD_PREP(KVM_HOST_PTE_OWNER_GUEST_HANDLE_MASK, handle) | + FIELD_PREP(KVM_HOST_PTE_OWNER_GUEST_GFN_MASK, gfn); +} + static bool host_stage2_force_pte_cb(u64 addr, u64 end, enum kvm_pgtable_prot prot) { /* @@ -1125,6 +1138,7 @@ int __pkvm_host_donate_guest(u64 pfn, u64 gfn, struct pkvm_hyp_vcpu *vcpu) struct pkvm_hyp_vm *vm = pkvm_hyp_vcpu_to_hyp_vm(vcpu); u64 phys = hyp_pfn_to_phys(pfn); u64 ipa = hyp_pfn_to_phys(gfn); + u64 meta; int ret; host_lock_component(); @@ -1138,7 +1152,9 @@ int __pkvm_host_donate_guest(u64 pfn, u64 gfn, struct pkvm_hyp_vcpu *vcpu) if (ret) goto unlock; - WARN_ON(host_stage2_set_owner_locked(phys, PAGE_SIZE, PKVM_ID_GUEST)); + meta = host_stage2_encode_gfn_meta(vm, gfn); + WARN_ON(host_stage2_set_owner_metadata_locked(phys, PAGE_SIZE, + PKVM_ID_GUEST, meta)); WARN_ON(kvm_pgtable_stage2_map(&vm->pgt, ipa, PAGE_SIZE, phys, pkvm_mkstate(KVM_PGTABLE_PROT_RWX, PKVM_PAGE_OWNED), &vcpu->vcpu.arch.pkvm_memcache, 0)); -- 2.53.0.1018.g2bb0e51243-goog