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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 B14FEC2D0BF for ; Mon, 16 Dec 2019 18:22:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 81324206EC for ; Mon, 16 Dec 2019 18:22:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576520539; bh=Mztc72BHnmEsloLyPFd/5QdIkJ/8JsaIrOr2c3E22Mg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=mvOVLqSzsVUM4IxApih3lH73/rRRciENCltTJ5unrB+IrdX4Ha9jYgWv6I5eQa+R2 sYWB5XaCRgVspLAC88VxlNDMvHOyEUHwwTIN6TmYWwBWL/0StwnVUvP5SqQ1zNsLtS ndkkPWhdV9lqQw1Pg9W8/FnqqCtwiKq/xFhDtyiM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732116AbfLPSVi (ORCPT ); Mon, 16 Dec 2019 13:21:38 -0500 Received: from mail.kernel.org ([198.145.29.99]:56456 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732110AbfLPSVh (ORCPT ); Mon, 16 Dec 2019 13:21:37 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9C94E206EC; Mon, 16 Dec 2019 18:21:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576520497; bh=Mztc72BHnmEsloLyPFd/5QdIkJ/8JsaIrOr2c3E22Mg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=egp7GGV9p9wZ+JFQK3cKlGZ9K6pI8DEyK1iTEk/beDK68HuHGzcvrMj8iIIG/Y6R6 okuC0+plGUFua/NDVy6+7Okel37SzEXMehRUKW2ADBgJRklu3n4mFStF/QtoXvecHO AgABnUMOjJ6H2014f+48EeS4YPSIXD/8U1zqT9zE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Qian Cai , ppc syzbot c/o Andrew Donnellan , Michael Ellerman , Daniel Axtens Subject: [PATCH 5.4 172/177] powerpc: Define arch_is_kernel_initmem_freed() for lockdep Date: Mon, 16 Dec 2019 18:50:28 +0100 Message-Id: <20191216174850.685064994@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191216174811.158424118@linuxfoundation.org> References: <20191216174811.158424118@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Michael Ellerman commit 6f07048c00fd100ed8cab66c225c157e0b6c0a50 upstream. Under certain circumstances, we hit a warning in lockdep_register_key: if (WARN_ON_ONCE(static_obj(key))) return; This occurs when the key falls into initmem that has since been freed and can now be reused. This has been observed on boot, and under memory pressure. Define arch_is_kernel_initmem_freed(), which allows lockdep to correctly identify this memory as dynamic. This fixes a bug picked up by the powerpc64 syzkaller instance where we hit the WARN via alloc_netdev_mqs. Reported-by: Qian Cai Reported-by: ppc syzbot c/o Andrew Donnellan Signed-off-by: Michael Ellerman Signed-off-by: Daniel Axtens Link: https://lore.kernel.org/r/87lfs4f7d6.fsf@dja-thinkpad.axtens.net Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/include/asm/sections.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) --- a/arch/powerpc/include/asm/sections.h +++ b/arch/powerpc/include/asm/sections.h @@ -5,8 +5,22 @@ #include #include + +#define arch_is_kernel_initmem_freed arch_is_kernel_initmem_freed + #include +extern bool init_mem_is_free; + +static inline int arch_is_kernel_initmem_freed(unsigned long addr) +{ + if (!init_mem_is_free) + return 0; + + return addr >= (unsigned long)__init_begin && + addr < (unsigned long)__init_end; +} + extern char __head_end[]; #ifdef __powerpc64__