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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 39A6AC433F5 for ; Tue, 19 Oct 2021 12:36:27 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 0AC6561057 for ; Tue, 19 Oct 2021 12:36:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 0AC6561057 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=axis.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:CC:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=hi4xd4q68UeL47TDIAMv2gNGiaaHGLAB99fl/tcYzHw=; b=P0/iFfHHZb1n0B OoGm/16hXB9fKRW9EiAmRM0pZ9heO2MbdWlx2CKLEgfHEZhvNMX2jLgAg7Z78GxFlvNUPV4wMd3b5 852oxB46ZQ1MH1UX5A4yq/M5aUMdqPNoo64pqnybqJgs8Mol/hPtVKvCwYCygojbI9fmWHlZwXMMT qeRZEcuCJcHsM+zHTQSkCXd4WhpjYrzXHu9J7XSWPDysz8w4eiVlDIB7Aim0b0V6qxOZFn0NxXJ9A c7jQT/ShXjQmWOQuB4i+gWVj9W/wInhrwPN8VgJnwxJrQqDHMcA/nzF2Zm9bKp34XAZCVXbGE4HRg bBYZ0AMbn0cVSo61hFOA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mcoKS-001EHL-6d; Tue, 19 Oct 2021 12:34:52 +0000 Received: from smtp2.axis.com ([195.60.68.18]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mcoIt-001DgN-MD for linux-arm-kernel@lists.infradead.org; Tue, 19 Oct 2021 12:33:17 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=axis.com; q=dns/txt; s=axis-central1; t=1634646795; x=1666182795; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=VZejVFBRwmJpF+m8eEegQmLVGPM2SFg4rdhcPABbUcE=; b=Pl+MCPuYetIFYVtuVqPkXagBaO99mmUKmX1yTHQr9RnORtOXp5LMYRLG jMD0aY+fX17Jrz6PChjDu4DT+PC2Meq0tYVc+FOQCgR278JBRZ+ZOdijS kWVj1Dana6dx2Vd1AkMH3Tz0QxmTNAqFDp2BreElGt52JBmGg1Zc++MjW kQTxz8953IIgQVz2QOoRqenIoSI5NLeLrzSqapm5x+88Xhva1frGZe88H xYYwcmmE93g0iz//w8gXfljdiKkymRoU7qikC3VsyCIO4yG1DEg04oGoF qdzjfXzErGeznoIZBMDcdWBEKxIX7lkLXn4ypF8XlsKLZVahQjU9SW3iY g==; Date: Tue, 19 Oct 2021 14:33:08 +0200 From: Vincent Whitchurch To: Will Deacon CC: Catalin Marinas , kernel , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] arm64: ptdump: Allow dumping user page tables Message-ID: <20211019123307.GA20031@axis.com> References: <20211001145603.22024-1-vincent.whitchurch@axis.com> <20211019120931.GJ13251@willie-the-truck> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20211019120931.GJ13251@willie-the-truck> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211019_053316_105152_28382C09 X-CRM114-Status: GOOD ( 14.66 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Oct 19, 2021 at 02:09:32PM +0200, Will Deacon wrote: > On Fri, Oct 01, 2021 at 04:56:03PM +0200, Vincent Whitchurch wrote: > > Add a user_page_tables debugfs file (similar to kernel_page_tables) to > > dump out the userspace page tables for the current process. This > > provides details which are not available via pagemap (such as the memory > > type) and is useful when, for example, debugging ->mmap() > > implementations. > > > > Signed-off-by: Vincent Whitchurch > > --- > > arch/arm64/mm/ptdump.c | 15 ++++++++++++++- > > 1 file changed, 14 insertions(+), 1 deletion(-) > > How does this serialise with things like task exit? A task can only read its own page tables using this file, and the mm lock is held during the walk in ptdump_walk_pgd(). Isn't that sufficient? _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel