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 6D3C5606A32D for ; Fri, 6 Nov 2026 13:30:26 +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=4LEXzSTL; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=XN36poyH 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=e/3XraEN+4mKAfyytUe7hFO8nk3KHRIKouz+zhkXDN0=; b=4LEXzSTLe6UFuY DtOW4u+GeGfdLnu1RyDTrYiUuAzpr6m8Nt0qsG515C3YjvrJKbpEa3iQCDkeUAobPFHmBfrS1w7mx JVGkfR7D5yWxkQ1rZXr+s2+Hksgu2ZPRD6+G6l2XFA/Lkt7CsQExatLgDNBOdw5HTgi1avK34Lfou m+P+ASsZtePtRcKA2GQMUVbB953/rtUZJM8hLuXhRyKRIaaLBI8AF4y90qSuw7H2VT+iXTSDBy2XI tGWj2y1kIfuskOigy2Ffhnbqi1X0bkzNZubmSMJ5dSmdnxQbQxUpf0TijumM2/DqPQMKIHEKiMM+b 5hnJq8YuOfAW7nVXTH6A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xPK1I-0000000CRPS-2phQ; Fri, 06 Nov 2026 13:30:16 +0000 Received: from out-58.mta0.migadu.com ([2001:41d0:1004:224b::3a] helo=mta0.migadu.com) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xPK1D-0000000CRK8-1ygI for linux-arm-kernel@lists.infradead.org; Fri, 06 Nov 2026 13:30:12 +0000 X-Envelope-To: linux-arm-kernel@lists.infradead.org DKIM-Signature: a=rsa-sha256; bh=n4Vsow1U4/zPQT8BxxJgvfPhA9r/J78hKay9DbA/hws=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793971808; v=1; x=1794576608; b=XN36poyHustH0MlLVgJjXZJY36PK5Gt1ynzAroBdRznA0OKgtvf3zjkFWf42BQx8BDrA+Lrs Ow9mVDR8pw8AytTAbYHfi+CytMkJvgYEMza3tUep7pUU++ky2ddpoxZXJC4pPZLlsdVWsFznv/A rkFpCDxVanGpoRtHkiItslXo= X-Envelope-To: linux-arm-kernel@lists.infradead.org Received: by smtp.migadu.com with ESMTPS id f286758a8028908b; Fri, 06 Nov 2026 13:30:08 +0000 X-Mizu-Trace-ID: f286758a8028908b 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 , Wei-Lin Chang , Fuad Tabba Subject: [PATCH v3 2/2] KVM: arm64: Resume a pKVM stage-2 teardown at the next mapping Date: Fri, 6 Nov 2026 13:30:00 +0000 Message-ID: <20261106133000.453240-3-fuad.tabba@linux.dev> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20261106133000.453240-1-fuad.tabba@linux.dev> References: <20261106133000.453240-1-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-20261106_053011_649610_76A68682 X-CRM114-Status: GOOD ( 11.51 ) 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 S64_MAX when none is left (U64_MAX would read as an error), 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 S64_MAX for it straight away. Reviewed-by: Vincent Donnefort Signed-off-by: Fuad Tabba --- arch/arm64/kvm/pkvm.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kvm/pkvm.c b/arch/arm64/kvm/pkvm.c index d0a6308008512..ef36875e25610 100644 --- a/arch/arm64/kvm/pkvm.c +++ b/arch/arm64/kvm/pkvm.c @@ -504,9 +504,10 @@ s64 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 S64_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 +519,9 @@ s64 pkvm_pgtable_stage2_destroy_range(struct kvm_pgtable *pgt, else __pkvm_pgtable_stage2_unshare(pgt, addr, addr + size); - return addr + size; + mapping = pkvm_mapping_iter_first(&pgt->pkvm_mappings, addr + size, U64_MAX); + + return mapping ? gfn_to_gpa(mapping->gfn) : S64_MAX; } void pkvm_pgtable_stage2_destroy_pgd(struct kvm_pgtable *pgt) -- 2.47.3