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 6A608E7717D for ; Wed, 11 Dec 2024 17:27:00 +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-Type:MIME-Version: References:Message-ID:In-Reply-To:Subject:cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=TdrJ0SbMmqk7tEl4kBb44qSI7X5fDQGS/pk1FZgb02Y=; b=Sn0mzX33HqidmKL0yIaprH84lb dP5hj5jBB56YlRqIF1OFd2KT9IgUxQnH2Nr8/n7+yzCTj622+YZ8vMZoLisEtQ3vv9WOgsb3j91tf wua/n75I4HzeGWiPyejUrc0Gq1BqEbFbNNO+LZsmm1DjVwiKrU0veSbFxy7apAFucwIYtLY5VCtEf 23cUx+2Nj5JGV6BxXeFeqF6FTtjsa2uaB5XncMnCti2gTG8HvCv6zw1gnPVR+gaOcaSSmrhW/LZKY ZRVrgTO0xZG4upyo5F9IplD2arEAQOEY0IUPitskaxwVVQN8UYcw12CYU/nsBfV9kvLdSG/1PBKkT kUqBZJKg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tLQU2-0000000Fb8m-0dqR; Wed, 11 Dec 2024 17:26:46 +0000 Received: from gentwo.org ([62.72.0.81]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tLQRv-0000000FaV4-21JI for linux-arm-kernel@lists.infradead.org; Wed, 11 Dec 2024 17:24:36 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gentwo.org; s=default; t=1733937873; bh=TdrJ0SbMmqk7tEl4kBb44qSI7X5fDQGS/pk1FZgb02Y=; h=Date:From:To:cc:Subject:In-Reply-To:References:From; b=Hwse0Ju8R5dII5eg932tcIQzr2y+1bY0mSoRggdOrl7iOAQiNvPGM7OzH26zxUVbf Jp3k5sWBsxRaLkttKizM6VOqb+1gkhL61u5O9aGuNJhSvlphpQNnltmfwFJHZxRiXV toNCDqZ5oXWivPlnkCWvSX3BX5DvEpkcDmXyKJ3Y= Received: by gentwo.org (Postfix, from userid 1003) id 7CAB8406EC; Wed, 11 Dec 2024 09:24:33 -0800 (PST) Received: from localhost (localhost [127.0.0.1]) by gentwo.org (Postfix) with ESMTP id 7BCB7401EF; Wed, 11 Dec 2024 09:24:33 -0800 (PST) Date: Wed, 11 Dec 2024 09:24:33 -0800 (PST) From: "Christoph Lameter (Ampere)" To: Will Deacon cc: Yang Shi , catalin.marinas@arm.com, scott@os.amperecomputing.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH 0/3] arm64: support FEAT_BBM level 2 and large block mapping when rodata=full In-Reply-To: <20241210113151.GC14735@willie-the-truck> Message-ID: <6714a00a-220e-c43b-7f06-4a2397159cd7@gentwo.org> References: <20241118181711.962576-1-yang@os.amperecomputing.com> <20241210113151.GC14735@willie-the-truck> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241211_092435_555792_8C90786D X-CRM114-Status: UNSURE ( 9.74 ) X-CRM114-Notice: Please train this message. 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 On Tue, 10 Dec 2024, Will Deacon wrote: > > With FEAT_BBM level 2 support, splitting large block page table to > > smaller ones doesn't need to make the page table entry invalid anymore. > > This allows kernel split large block mapping on the fly. > > I think you can still get TLB conflict aborts in this case, so this > doesn't work. Hopefully the architecture can strengthen this in the Which platforms get TLB conflicts? Ours does not. Is this an errata on some platforms?