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=-8.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_MED,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 EF05BC43141 for ; Thu, 21 Jun 2018 12:32:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A99F520837 for ; Thu, 21 Jun 2018 12:32:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="nAO7j46w" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A99F520837 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933795AbeFUMcx (ORCPT ); Thu, 21 Jun 2018 08:32:53 -0400 Received: from mail-oi0-f68.google.com ([209.85.218.68]:33563 "EHLO mail-oi0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933675AbeFUMcu (ORCPT ); Thu, 21 Jun 2018 08:32:50 -0400 Received: by mail-oi0-f68.google.com with SMTP id c6-v6so2768653oiy.0 for ; Thu, 21 Jun 2018 05:32:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ksWf7PO1RkuCKYAkyFetbv7366xS9mHzoZ3UYDMiqGo=; b=nAO7j46wDT97FFbwz0iUbYJLznH0RsaSCnQRNulZIW8regsLoaKtqB3f5p8Y0ju8ly /8NE/1gEGZlXgCfSOtFFalo2l3PyCcOoxg7Py6mQkkmoub6TplTVVLCdrlcKQ6X1OARB YrcqjYBk19FpLnWdyWKkwEyRpeeER42wdmdUCeMLmizFt0uBdFs0qj0PegOyDy0ryT5t JR+jsXYDW1JS9u3e86YsXQZnvlISukK1CqI0SEOJl/WoG4bKAGR32EQqhVtsdQMFli3l vso1c3G1xtG+eN4lEPEvrCT4UvVHfaiyqQssXKudpY9A7IyPiG7A4aHI5jIUN0jOeAsN VhCA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ksWf7PO1RkuCKYAkyFetbv7366xS9mHzoZ3UYDMiqGo=; b=lRrutSFXul09O4vFYpx6tnnN48p3gOIjEOxTT9O9btNHnFtMqmdRCeAnST7nECO4rS ytjjEFrIgFYlJ13BRjPTwwFYKPtMuIix6S8+wZ5p87U4kurqp02HLNtsxBSlAeRIMUwF G+q+pfxeJHEVlnYD14E1GV+hE5iU5zXuRif7Gkez3J2KHF7ley+KzUkfuJLuWCMrgGvE gJy/Ju9OJfpkbdY67r7h4POKhsBwZkivt0a2h2TrTfoccTenZ2WgpYQXeBQlcgjZqTyk RiAytuJQ6KKSTBQ9F9SNSGfpEn4gczSQnFqoRu/SN0YMLFyIAXRa1BfUekuS2P68HPiY zJDQ== X-Gm-Message-State: APt69E3XdyH3wQDmWTNHi2cnRt4LDLGyjf2j3Qnp5r0BKv7Rky/1vLDX q5C+GeoLAGKj84zetxAcx4WCCdat3fcEzX1dTE/Vrw== X-Google-Smtp-Source: ADUXVKIhd5EJNSB8X6WRWApP/oi1ruLXJUim42TGry6FOpZ2RvZsF7yfvUWFx/U/icXxMvxv/CGQcemwKQiyUR1FTbA= X-Received: by 2002:aca:ab15:: with SMTP id u21-v6mr14683858oie.272.1529584369880; Thu, 21 Jun 2018 05:32:49 -0700 (PDT) MIME-Version: 1.0 References: <1529532570-21765-1-git-send-email-rick.p.edgecombe@intel.com> <1529532570-21765-4-git-send-email-rick.p.edgecombe@intel.com> In-Reply-To: <1529532570-21765-4-git-send-email-rick.p.edgecombe@intel.com> From: Jann Horn Date: Thu, 21 Jun 2018 14:32:38 +0200 Message-ID: Subject: Re: [PATCH 3/3] vmalloc: Add debugfs modfraginfo To: rick.p.edgecombe@intel.com Cc: Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , "the arch/x86 maintainers" , kernel list , Linux-MM , Kernel Hardening , kristen.c.accardi@intel.com, Dave Hansen , arjan.van.de.ven@intel.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 21, 2018 at 12:12 AM Rick Edgecombe wrote: > Add debugfs file "modfraginfo" for providing info on module space > fragmentation. This can be used for determining if loadable module > randomization is causing any problems for extreme module loading situations, > like huge numbers of modules or extremely large modules. > > Sample output when RANDOMIZE_BASE and X86_64 is configured: > Largest free space: 847253504 > External Memory Fragementation: 20% > Allocations in backup area: 0 > > Sample output otherwise: > Largest free space: 847253504 > External Memory Fragementation: 20% [...] > + seq_printf(m, "Largest free space:\t\t%lu\n", largest_free); > + if (total_free) > + seq_printf(m, "External Memory Fragementation:\t%lu%%\n", "Fragmentation" > + 100-(100*largest_free/total_free)); > + else > + seq_puts(m, "External Memory Fragementation:\t0%%\n"); "Fragmentation" [...] > +static const struct file_operations debug_module_frag_operations = { > + .open = proc_module_frag_debug_open, > + .read = seq_read, > + .llseek = seq_lseek, > + .release = single_release, > +}; > > +static void debug_modfrag_init(void) > +{ > + debugfs_create_file("modfraginfo", 0x0400, NULL, NULL, > + &debug_module_frag_operations); 0x0400 is 02000, which is the setgid bit. I think you meant to type 0400?