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 X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 80A2DC433DB for ; Tue, 2 Feb 2021 13:31:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4B9C164DBD for ; Tue, 2 Feb 2021 13:31:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232370AbhBBNbe (ORCPT ); Tue, 2 Feb 2021 08:31:34 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:31171 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231860AbhBBNas (ORCPT ); Tue, 2 Feb 2021 08:30:48 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612272561; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=XvwRtVP5vp80IXVInMVRsjcG2OB+pyvOocXOW5/K1lg=; b=PenMMhzh5DV+Mwm5WudHGfimfYX5lIE2nm9W/FOoGnDWW3d8k9u4Vf5gMZ5Z1E8Np6+MDF MFGjvvfHZay6ZzxHL5zF/wB+G69GRfzXtCEWWxMTWnDYV9iVdYh17KZrIWbKn36xn+f/Co z22tbEqOQjULFe95cEK8N69jXKJOjp0= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-27-RfqjVO5yMKuZ1F_Ryx1DAw-1; Tue, 02 Feb 2021 08:29:16 -0500 X-MC-Unique: RfqjVO5yMKuZ1F_Ryx1DAw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 8652B195D560; Tue, 2 Feb 2021 13:29:14 +0000 (UTC) Received: from [10.36.114.148] (ovpn-114-148.ams2.redhat.com [10.36.114.148]) by smtp.corp.redhat.com (Postfix) with ESMTP id D8E9B36FA; Tue, 2 Feb 2021 13:29:11 +0000 (UTC) To: Oscar Salvador , Andrew Morton Cc: Dave Hansen , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H . Peter Anvin" , Michal Hocko , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20210202112450.11932-1-osalvador@suse.de> <20210202112450.11932-3-osalvador@suse.de> From: David Hildenbrand Organization: Red Hat GmbH Subject: Re: [PATCH 2/2] x86/vmemmap: Handle unpopulated sub-pmd ranges Message-ID: Date: Tue, 2 Feb 2021 14:29:11 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: <20210202112450.11932-3-osalvador@suse.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > @@ -1088,10 +1150,10 @@ remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end, > pages++; > } else { > /* If here, we are freeing vmemmap pages. */ > - memset((void *)addr, PAGE_INUSE, next - addr); > + memset((void *)addr, PAGE_UNUSED, next - addr); > > page_addr = page_address(pud_page(*pud)); > - if (!memchr_inv(page_addr, PAGE_INUSE, > + if (!memchr_inv(page_addr, PAGE_UNUSED, > PUD_SIZE)) { > free_pagetable(pud_page(*pud), > get_order(PUD_SIZE)); I'm sorry to bother you again, but isn't that dead code as well? How do we ever end up using 1GB pages for the vmemmap? At least not via vmemmap_populate() - so I guess never? There are not many occurrences of "PUD_SIZE" in the file after all ... I think we can simplify that code. -- Thanks, David / dhildenb