From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gentwo.org (gentwo.org [62.72.0.81]) (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 AAF821FE479 for ; Wed, 11 Dec 2024 17:24:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.72.0.81 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733937881; cv=none; b=cuzGm+MzCP8LgQw2kureHBisp+j08xEYIyxFPmfYe5/oIn5IxhGf3G7aoCF9NkV7Pa0+FsmiB4KxOOHEc8Wm7OoUz3papo6Ae+tgYVCffYMaH5ttIQEG+Q4msbpE6juc+u7Ti4FFT4d89QbPOZD5oBz9SPpwxPW1r5YP5ip/ctw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733937881; c=relaxed/simple; bh=TdrJ0SbMmqk7tEl4kBb44qSI7X5fDQGS/pk1FZgb02Y=; h=Date:From:To:cc:Subject:In-Reply-To:Message-ID:References: MIME-Version:Content-Type; b=o19RLQpx7Gcz0SfI2ncDjR2tusovlLXlVvX6BYRxfmpGpLubhWnL97Tl6v6yt/5NHhxi2y6VAwNApgqRN3ApRRfi+m0fa+TyBizE+QE8rzVwnukT0ATe+1PNG6dVn/dZoy9/g864r7AgXrPw9/iEQeVZc5u0rYfu2nI3B2L4KIE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=gentwo.org; spf=pass smtp.mailfrom=gentwo.org; dkim=pass (1024-bit key) header.d=gentwo.org header.i=@gentwo.org header.b=Hwse0Ju8; arc=none smtp.client-ip=62.72.0.81 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=gentwo.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gentwo.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=gentwo.org header.i=@gentwo.org header.b="Hwse0Ju8" 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> 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 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?