From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=95.215.58.135 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793796296; b=BOwWIphOR56G7uJjkQG+Y7AmAiQ90R3ZHr+mxtnH3rWcKEVO8OeRRoqkxfXhO72RyK1w lrEI8qDSiakHguP/JngZiSFjxjMU15kBjgmfLgrvC67DJLMSu55sxhmvS2nLrSb38iV+e 6NLcYol6wiKbQYVwa63qwG7PtAU3XTpsFD7fUzv2hitnSxE+8HLo1UELYmF6EQ0FLy+/o gDp6kQ4BuhZ97bDLDukkvLJflMmy/9+oX9BtasePqp7F8OT84oLmcDd88+elt/C+Bgcil TXpwt5wPQhR8lNLIc75+eo22F5TgzRI0+EULdgeeIFphjhv0vmpssbIQGMnd/HF7KwA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793796296; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:From:To:Cc:Subject:Date:Message-ID: X-Mailer:MIME-Version:Content-Transfer-Encoding; bh=UcjFubjphnzFpUpHrLLrETqweYn/e3Sdi2+JtZw/B0I=; b=jClSiXo8J056dLqtwLTyZ089jV4ja2vopyG9v42XmcQgcney+VtiCQpV80DMHaQxEG6M K6Mi/rAZ+Dl38TdToDvv0p+tHfH7B+hlZnz3TCg4mUnHGiGzc+FA+gxKqj2vYU93KJYwx 4qnVVthzC3bkQTBtU/nlXwGQhqbkawJwrRXUvkcVSlMuVV0mZcimsXE60+hqdIFOd5tRe /71vPSOwLK98KzZG5Kn4fgrb/xoKgqAnnrbFMCyLVClV2n4AAP83rp+EZsWcnE6v7NIfN UkAbtzPKOBZKUori0SfBHkAn0pNM2NDUAJKJr7t7g8E+F8rQiFTeQY8sR9UDnQ9ldow== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=V3DZfkWI; arc=none smtp.remote-ip=95.215.58.135 Received: from mta1.migadu.com (out-135.mta1.migadu.com [95.215.58.135]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C91DD606A32E for ; Wed, 4 Nov 2026 12:44:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org C91DD606A32E Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=V3DZfkWI X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=pL42GIo48cBII9Atlc96cBdXylzrs2P95YUPiNb6rRA=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793796292; v=1; x=1794401092; b=V3DZfkWIbPloGmUQ/qeDD6rSp4jbZu/KGxXnHYq7UlrPV5Q4kSA8MZgwpIxBJgOJpmBeDa4y X8nvMFn1i8Aq4TmsqVPbsGFEAoQps7HmWM1tssK1c3p+a+fLgUpBi8jVf4kPvtN532zQvP/1IfW 8JSqa9IcrKA31EVmJscmC+Yo= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id d939a9b5ae201b1c; Wed, 04 Nov 2026 12:44:52 +0000 X-Mizu-Trace-ID: d939a9b5ae201b1c 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 0/2] KVM: arm64: Stop stage-2 teardown scaling with the IPA size Date: Wed, 4 Nov 2026 12:44:49 +0000 Message-ID: <20261104124451.2148724-1-fuad.tabba@linux.dev> X-Mailer: git-send-email 2.47.3 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi folks, Changes since v1 [1]: - Run all teardown from stage2_destroy_range() (Oliver, Suzuki) - Dropped the Fixes tags (Marc) - Dropped the patch moving the teardown into kvm_vm_s2_ops - Use gfn_to_gpa() for a mapping's address. (Vincent) Two patches that make stage-2 teardown take time proportional to what is mapped, rather than to the size of the IPA space as it has since 4ddfab5436b6. Under QEMU TCG ('-cpu max', 16K pages with LPA2), destroying even an empty VM takes about 7 seconds in pKVM. Without pKVM it takes about 19 seconds if the VM requests a 52-bit IPA (crosvm requests the host's limit). With the series, both take well under a second. I tested only under QEMU, since I don't have hardware with LPA2. The first has the page-table walk return where it stopped, so that the teardown steps over an invalid entry larger than a block-sized chunk in one go. The second has pKVM return where its next mapping starts. pKVM gives every VM the host's IPA limit. My series honoring KVM_VM_TYPE_ARM_IPA_SIZE in pKVM [2] doesn't change that for crosvm, which requests the limit. Based on Linux 7.4-rc1 (6628e7d4c6b25). Cheers, /fuad [1] https://lore.kernel.org/all/20261103084742.1302597-1-fuad.tabba@linux.dev/ [2] https://lore.kernel.org/all/20260917091826.2639205-1-fuad.tabba@linux.dev/ Fuad Tabba (2): KVM: arm64: Resume stage-2 teardown where the walk stopped KVM: arm64: Resume a pKVM stage-2 teardown at the next mapping arch/arm64/include/asm/kvm_pgtable.h | 8 ++++++-- arch/arm64/include/asm/kvm_pkvm.h | 4 ++-- arch/arm64/kvm/hyp/pgtable.c | 15 ++++++++++++--- arch/arm64/kvm/mmu.c | 4 ++-- arch/arm64/kvm/pkvm.c | 12 +++++++++--- 5 files changed, 31 insertions(+), 12 deletions(-) base-commit: 6628e7d4c6b25c8d18f1345e3a20d21829aae7e4 -- 2.47.3