From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from esa1.hc1455-7.c3s2.iphmx.com (esa1.hc1455-7.c3s2.iphmx.com [207.54.90.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0C57E2E4257 for ; Fri, 29 May 2026 00:56:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=207.54.90.47 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780016203; cv=none; b=Hh/IAygW8PiTcl2Fn0c2O7tPyiSgtesif6MZg5i9WMcRiJS721yJELwTL8Ulq8FIUssUhmFyoXyVe7KKcq9+kseYZqE91gy2Afzer1qbft0g/OpBXdh+BPW7x7BvcF3wyFMkhxnkTJ6m1vQUAPbsaTfWZDqYlv8xrhclT5/GXDg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780016203; c=relaxed/simple; bh=lhpPtqrPlN22mh1WZzcu3aj/wlFlJxXUx2s+ET5Hoyw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=VzwdmCM7aKozkCFLJrVg7z376STd2FzzJPBtVRtampCXrjQ74zK5UCCmcW4KC9yZ5D5oSI2mCswYMeducNzszVwXDZvIrVQ1CSW6W/buLCQMBNiWVVoqdYsgF1IDZBHdlwZb+GjViz+gB/Lio+i8QFzywDlQHc7rwy6WLNRIgk8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=fujitsu.com; spf=pass smtp.mailfrom=fujitsu.com; dkim=pass (2048-bit key) header.d=fujitsu.com header.i=@fujitsu.com header.b=NIJCUxKY; arc=none smtp.client-ip=207.54.90.47 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=fujitsu.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=fujitsu.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=fujitsu.com header.i=@fujitsu.com header.b="NIJCUxKY" DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=fujitsu.com; i=@fujitsu.com; q=dns/txt; s=fj2; t=1780016202; x=1811552202; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=lhpPtqrPlN22mh1WZzcu3aj/wlFlJxXUx2s+ET5Hoyw=; b=NIJCUxKYd1j7GWCmGZmdh0ePqlipUcTww4LthXn5NyzXqnEZKDIzzTTp G10gl2WlPNYq8/AbnA0S5KocVcftDHBgR2XrlGHHAPTkTAlnGXkwNpiyj Ml16qW2StGBSxf2kHxsivYlu3MAa7uqVebenDda0IRHAKixYsmrkRfNgb OMIK3yXlMBXWYEp4mFKNK6yig7w8RKRp5dd4VqCKdnO+syA7mi2nwvZG6 XdGZYy1zSc8nXKqv5SpF2g0o56CisYmepdUpjJQzz5RvpE0ePFqLKz2/8 Oe7yCvt+N6Nji2BCWsNusvxjNcwUCZHavQ8APo3+247wJ+uddTksS7Y6r w==; X-CSE-ConnectionGUID: SE5QXH1KT36wfnS0Y400Ug== X-CSE-MsgGUID: RANEj3yhTN2w+EpU3p1NiQ== X-IronPort-AV: E=McAfee;i="6800,10657,11800"; a="242244397" X-IronPort-AV: E=Sophos;i="6.24,174,1774278000"; d="scan'208";a="242244397" Received: from gmgwnl01.global.fujitsu.com ([52.143.17.124]) by esa1.hc1455-7.c3s2.iphmx.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 May 2026 09:55:32 +0900 Received: from az2nlsmgm3.fujitsu.com (unknown [10.150.26.205]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by gmgwnl01.global.fujitsu.com (Postfix) with ESMTPS id 9BD09407551 for ; Fri, 29 May 2026 00:55:31 +0000 (UTC) Received: from az2nlsmom4.fujitsu.com (unknown [10.150.26.201]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by az2nlsmgm3.fujitsu.com (Postfix) with ESMTPS id 4FD251800D6D for ; Fri, 29 May 2026 00:55:31 +0000 (UTC) Received: from sm-arm-grace07 (unknown [10.124.178.20]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by az2nlsmom4.fujitsu.com (Postfix) with ESMTPS id 128DA2000752; Fri, 29 May 2026 00:55:26 +0000 (UTC) Date: Fri, 29 May 2026 09:55:24 +0900 From: Itaru Kitayama To: Marc Zyngier Cc: Wei-Lin Chang , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, Oliver Upton , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon Subject: Re: [PATCH v3 0/5] KVM: arm64: nv: Implement nested stage-2 reverse map Message-ID: References: <20260510145338.322962-1-weilin.chang@arm.com> <86fr3bvnt5.wl-maz@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <86fr3bvnt5.wl-maz@kernel.org> On Thu, May 28, 2026 at 11:19:34AM +0100, Marc Zyngier wrote: > On Wed, 20 May 2026 08:31:12 +0100, > Itaru Kitayama wrote: > > > > Hi Wei Lin, > > > > On Sun, May 10, 2026 at 03:53:33PM +0100, Wei-Lin Chang wrote: > > > Hi, > > > > > > This is v3 of optimizing the shadow s2 mmu unmapping during MMU > > > notifiers. > > > > > > Two new preparatory patches are added, one reduces a hole in kvm_s2_mmu > > > and another refactors the code a bit during s2 faults. Other changes are > > > listed below. > > > > > > * Changes from v2 [1]: > > > > > > - Removed "polluted" teminology. > > > > > > - Use xa_{mk, to}_value() when storing and retriving values from maple > > > trees. > > > > > > - Avoid using the 63rd bit in maple tree values so that xa_{mk, to}_value() > > > does not lose us a bit. > > > > > > - Added reverse map removal during TLBI handling. > > > > > > - Other suggested refactorings. > > > > > > Thanks! > > > > With this series applied on the recent kvmarm/fixes (minor local modification), > > your v3 hello_nested runs fine on all three page granules; without this 16KB > > kernel can't handle stage 2 unmapping paths. I tested using the latest QEMU only > > so wonder how you're testing. > > Can you clarify this statement? > > Are you saying that 16kB S2 unmap do not work with upstream? That > seems odd, as it would mean NV wouldn't work on Apple HW, which > represents two thirds of my development boxes... Yes, I built this morning's upstream kvmarm/fixes with 16KB granule fresh, and tested Wei Lin's propsed KVM selftest, hello_nested on QEMU with the small buildroot filesystem and saw the above i.e., the stage 2 unmapping paths never finish. I thought it was due to the Ubuntu userspace I was using for testing, but not sure now. Thanks, Itaru. > > Thanks, > > M. > > -- > Without deviation from the norm, progress is not possible.