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 3DB75F33A78 for ; Thu, 5 Mar 2026 14:45:38 +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=7n2woGa5JxBpN83JF2+UPgtFTqclEjNN4o4ndffPkNY=; b=3WXULhJ80m+cBlDCLkyVdMrpeQ rCIr82eO0cI4lPRxm671or57PfLFTkozzawDB6kkd5L+jEhHnTHbtExqjCy0ynTfAEWLC1gnVkTse SKPqzSa+s8TJBYiaFhk/We7L1XNpp06woZrpDvHnEhtS2ybyZOUwUPI3a9cn51nWd7NQivSyennJK 5btzXuVYRH0SzJVXPbijxEMfr26+EbykKZVV8UDmdyQ7cuaU8KwbJ6z+8PRd+meK6k+X8m5o6f1bY JW6UzVDbpdMbnaznOmt+KGfEPaTIvnFLNZp+SO7amSVpqa4wuc5vXOVQ41WnvjvdwXvAwLMKn6Nd7 xYT+aYzw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vy9xF-000000022J2-1b6k; Thu, 05 Mar 2026 14:45:33 +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 1vy9xD-000000022G2-2jqe for linux-arm-kernel@lists.infradead.org; Thu, 05 Mar 2026 14:45:31 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 02EB061859; Thu, 5 Mar 2026 14:45:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C8516C2BC87; Thu, 5 Mar 2026 14:45:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772721930; bh=vdgsxQ+KX14BSB3ns8FdNXFw052PhZg+HzhbARyR850=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WMkWR+d5g25gaJINS9iLGI1+6hKljYjYVqhz0IWpxlJwKqSCRuwRCxesqn/CXUZE0 gZqegnvruU5rM2+LnBlrY4SE3hbS6oKt9axbLuOMRpaQiYw7LCj9F6Zq70qGpZ7Zqr KfK2SbTA/qbTA1JFxDGUAn8R7YsWAePomRBBQKlE/QSwR0VVvei4l4AAGvlfaZRUEX RmOdTb6EH1mOEgFxaa7DzTHTSvPSRQN3cwq/og0ucYV6vd3/1voQfxjkt8U92fAEdK /Y87FMvJpYXJcTHSw11iTOVOJ3b1JT8KuM3IGbXAcPYarcDsgYV1kglLy8c+oMmXZL pRTeEE47AsJ1w== 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 v3 23/36] KVM: arm64: Annotate guest donations with handle and gfn in host stage-2 Date: Thu, 5 Mar 2026 14:43:36 +0000 Message-ID: <20260305144351.17071-24-will@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260305144351.17071-1-will@kernel.org> References: <20260305144351.17071-1-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 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 ed540ccd1595..3b2f7d4c4936 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)); -- 2.53.0.473.g4a7958ca14-goog