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=-4.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 51E5FC4360F for ; Thu, 21 Mar 2019 18:17:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 27F2C2190A for ; Thu, 21 Mar 2019 18:17:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lca.pw header.i=@lca.pw header.b="Zi5ZwJ9P" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728553AbfCUSRu (ORCPT ); Thu, 21 Mar 2019 14:17:50 -0400 Received: from mail-qt1-f194.google.com ([209.85.160.194]:40161 "EHLO mail-qt1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725985AbfCUSRt (ORCPT ); Thu, 21 Mar 2019 14:17:49 -0400 Received: by mail-qt1-f194.google.com with SMTP id x12so7702325qts.7 for ; Thu, 21 Mar 2019 11:17:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lca.pw; s=google; h=message-id:subject:from:to:cc:date:in-reply-to:references :mime-version:content-transfer-encoding; bh=nq8thke8AAguuyUY8uu9Lf6Dq379TbWozTWnKwSQ0mI=; b=Zi5ZwJ9PlIvYa8DSIECnCbalBEUOgpuIjs0WSCG2SBnJE3ZhZkUFul6HDdWAPJOpm/ piNYKFb/BK51xfBlq6w+3wwCe3eqEhGAPLmvFGltK1Ht4S5KdIAAixYx9+nSOYDvcd3I D0/DmsQB8QLDsVb+5TTjidvoroLdSDYNPAnrCx1lr9OIGPoqFzmcl6K0eVH6kXQPcmFW s1xCXBYk3n8A0Q27DgEkin8ZicHNgBWqWB5bU7lRwF7qCFB98N1fFnDWM6mB/yQFmjbC lr8JiyF6yc9sdanvfv0IorpMOnScmhIiiOwlQx9Z9LilQEymcGGTYGhk345mlqW1hRrE RNrw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:subject:from:to:cc:date:in-reply-to :references:mime-version:content-transfer-encoding; bh=nq8thke8AAguuyUY8uu9Lf6Dq379TbWozTWnKwSQ0mI=; b=TliwwqtOQ/usFUFmBhXLo6amkOJP/W/BP8C99k0sbabhw+TxWeIzNtnykepRy4vxDj kRsDwawf8jbu1/XA27V25thon9m6j/HmANUkj77b6yKmWBp9+vi4ELYG5Ib1+bjyESoo A0ILgIhAmF9ObwAZZNQbvdYlMGsYfiKIsISG2QKnjL22MIOCZG/rNBbLBgnJmdUMbFSH pYwx/5LTEj+Qre8D2HEXtXlWhbCZxRpOaZUb15yKR7xBgYVEOwJAE2nfHLgpt90qVxD2 9lpaGmRp2T19o36bU1o6BIzIlruFoZ8Ekvdgir6p5XGDF6BPSYSf8vVGnN1ykTFMqtxT 61xg== X-Gm-Message-State: APjAAAWyQI9SWtWG/GgNWeGTInrGaiHbWJXjVhRAXcnxLmM6EZTXJyMs wYK2CmMC9xJLBflC6eZseiJ5Iw== X-Google-Smtp-Source: APXvYqzH4lZLJtvN18IQVcBYAAWDGWi+UZTAC3zqVsSviENEchLNO0/tfVB35Kl8u2oUO+FPu+1H4A== X-Received: by 2002:ac8:3113:: with SMTP id g19mr4420688qtb.356.1553192268668; Thu, 21 Mar 2019 11:17:48 -0700 (PDT) Received: from dhcp-41-57.bos.redhat.com (nat-pool-bos-t.redhat.com. [66.187.233.206]) by smtp.gmail.com with ESMTPSA id y17sm3021889qtf.72.2019.03.21.11.17.47 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 21 Mar 2019 11:17:48 -0700 (PDT) Message-ID: <1553192266.26196.16.camel@lca.pw> Subject: Re: [PATCH] kmemleak: powerpc: skip scanning holes in the .bss section From: Qian Cai To: Catalin Marinas , Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, kvm-ppc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Michael Ellerman Date: Thu, 21 Mar 2019 14:17:46 -0400 In-Reply-To: <20190321171917.62049-1-catalin.marinas@arm.com> References: <20190321171917.62049-1-catalin.marinas@arm.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.22.6 (3.22.6-10.el7) Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2019-03-21 at 17:19 +0000, Catalin Marinas wrote: > The commit 2d4f567103ff ("KVM: PPC: Introduce kvm_tmp framework") adds > kvm_tmp[] into the .bss section and then free the rest of unused spaces > back to the page allocator. > > kernel_init >   kvm_guest_init >     kvm_free_tmp >       free_reserved_area >         free_unref_page >           free_unref_page_prepare > > With DEBUG_PAGEALLOC=y, it will unmap those pages from kernel. As the > result, kmemleak scan will trigger a panic when it scans the .bss > section with unmapped pages. > > This patch creates dedicated kmemleak objects for the .data, .bss and > potentially .data..ro_after_init sections to allow partial freeing via > the kmemleak_free_part() in the powerpc kvm_free_tmp() function. > > Acked-by: Michael Ellerman (powerpc) > Reported-by: Qian Cai > Signed-off-by: Catalin Marinas Tested-by: Qian Cai