From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5F821606A33C for ; Wed, 4 Nov 2026 12:45:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=vmbpULkc; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=LJ4IguBc 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-Unsubscribe-Post: List-Owner; bh=txtaZAcRMKdG/6PvTtOqQBPubj70UFKtaDsquMMzFvw=; b=vmbpULkcbKyNk0 odF/OhOcEDz6875zAGjPyBt5u++oU21Ow9i1l1R9DaUDsY+yEq+ID3rXnb9awXcNw2u6oQCJx3nI6 ggqxYCMsOhrtAKP2n5SPSKl6Y+pairXGVglFMK96/bFwLqURgLfw8wt1cp8Y6m6l1XWIj9bl+zGYx 3eyjgU6djYkA8box96V0GdFXWgKddzZHGSK+k2dGeLl1HeskJLGjARYm3FJfqPn19e2SrZXQtO2jO vYrelzvigsUEN8eDquyTNa7ujKck4nTZE11PqG5LsYqSLHWmbADtzLIMnsCPAiGbxmT1Hn0mNeYbg hRMTF4JzLMbt8uZg220Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xOaMO-00000005Mmg-06Qg; Wed, 04 Nov 2026 12:45:00 +0000 Received: from out-152.mta1.migadu.com ([95.215.58.152] helo=mta1.migadu.com) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xOaMJ-00000005Mkv-2H6d for linux-arm-kernel@lists.infradead.org; Wed, 04 Nov 2026 12:44:58 +0000 X-Envelope-To: linux-arm-kernel@lists.infradead.org DKIM-Signature: a=rsa-sha256; bh=QEva7TCaSMpCjlP1oVH5gOdE6FBEUp30xJbq+yDM/Y0=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793796293; v=1; x=1794401093; b=LJ4IguBc02zgkRjzp5f0Z2EurZt1jYdFb4ffyLRG9VK5ObfCDxQmBNZ2sUzTo8FIKWyfVdTu PQC4fr/4DSYkvOhK/Z4GINxzS/4ERWdXxAJYErs274q7t5B98uuUPLW14xLy7VgoRC04ty/bb/X XPfPZw8jc1nq4G1k6QrYdaVA= X-Envelope-To: linux-arm-kernel@lists.infradead.org Received: by smtp.migadu.com with ESMTPS id 05ef130eda10926c; Wed, 04 Nov 2026 12:44:53 +0000 X-Mizu-Trace-ID: 05ef130eda10926c X-Migadu-Flow: FLOW_OUT From: Fuad Tabba To: Marc Zyngier , Oliver Upton Cc: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Joey Gouly , Steffen Eiden , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , Mark Rutland , Raghavendra Rao Ananta , Vincent Donnefort , Fuad Tabba Subject: [PATCH v2 2/2] KVM: arm64: Resume a pKVM stage-2 teardown at the next mapping Date: Wed, 4 Nov 2026 12:44:51 +0000 Message-ID: <20261104124451.2148724-3-fuad.tabba@linux.dev> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20261104124451.2148724-1-fuad.tabba@linux.dev> References: <20261104124451.2148724-1-fuad.tabba@linux.dev> X-Archived-By: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261104_044456_924181_6EA5A069 X-CRM114-Status: GOOD ( 12.46 ) X-Spam-Score: -2.1 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-18.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 pKVM keeps a VM's stage-2 mappings in an interval tree, and pkvm_pgtable_stage2_destroy_range() releases the ones in its range. stage2_destroy_range() still calls it for every block-sized chunk of the IPA space. As pKVM gives every VM the host's IPA limit, a teardown with LPA2 makes 2^27 calls with 16K pages (2^22 with 4K), however little the VM maps. Return the address of the next mapping instead, or U64_MAX when none is left, so that the teardown skips the space between mappings. No mapping crosses a chunk boundary, as pKVM maps at most PMD_SIZE, so the next one starts at or above the end of the range. A VM without a handle doesn't have anything mapped, so return U64_MAX for it straight away. Signed-off-by: Fuad Tabba --- arch/arm64/kvm/pkvm.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kvm/pkvm.c b/arch/arm64/kvm/pkvm.c index f21c3326dda68..77315c83c61b3 100644 --- a/arch/arm64/kvm/pkvm.c +++ b/arch/arm64/kvm/pkvm.c @@ -504,9 +504,10 @@ u64 pkvm_pgtable_stage2_destroy_range(struct kvm_pgtable *pgt, { struct kvm *kvm = kvm_s2_mmu_to_kvm(pgt->mmu); pkvm_handle_t handle = kvm->arch.pkvm.handle; + struct pkvm_mapping *mapping; if (!handle) - return addr + size; + return U64_MAX; if (pkvm_hyp_vm_is_created(kvm) && !kvm->arch.pkvm.is_dying) { WARN_ON(kvm_call_hyp_nvhe(__pkvm_start_teardown_vm, handle)); @@ -518,7 +519,10 @@ u64 pkvm_pgtable_stage2_destroy_range(struct kvm_pgtable *pgt, else __pkvm_pgtable_stage2_unshare(pgt, addr, addr + size); - return addr + size; + /* Mappings left by a failed release are still in the tree, so look past the range. */ + mapping = pkvm_mapping_iter_first(&pgt->pkvm_mappings, addr + size, U64_MAX); + + return mapping ? gfn_to_gpa(mapping->gfn) : U64_MAX; } void pkvm_pgtable_stage2_destroy_pgd(struct kvm_pgtable *pgt) -- 2.47.3