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=-2.1 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID, USER_AGENT_MUTT 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 2704AC43334 for ; Wed, 5 Sep 2018 11:48:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C6DB720659 for ; Wed, 5 Sep 2018 11:48:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="mXE2D0wy" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C6DB720659 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org 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 S1727568AbeIEQSj (ORCPT ); Wed, 5 Sep 2018 12:18:39 -0400 Received: from merlin.infradead.org ([205.233.59.134]:60760 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726311AbeIEQSj (ORCPT ); Wed, 5 Sep 2018 12:18:39 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=/nMfqAiw0FAmFBXAMP3SpJUZXs4gyHws8ers0ywVPoQ=; b=mXE2D0wy5YQ7NM4SPJ/yhj4i+ R0IEpJBUm9QgbpDxRJTJySImOQmbSJnARk5iRVoGkMg8pDky6y2bpmKYyxtnRGgk9fqtmmDXkoN2g TG8jPXjYYfkV5/8pUwa3ZRByBHNhLetpA2cqVfel9rJ8e3GnRpTUJHnbz1quNnDj18uyEy4+3PklW kuv36rNK88pTVP80+fGD3kQIl7IAybdHabbH57YevMzIw4ZKP9DsKECCLq/dvVg8HX7erNA/OdG7a 5wknyGbpnOTbfF16/QnZrWkfsVv8pMRPAFbm35yqY0COIOBE3zhxcxLk7Aqe9hCaCILy8kD1bVBdf NsskP/3YQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1fxWIU-00051W-Md; Wed, 05 Sep 2018 11:48:34 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 62B02202AFE0E; Wed, 5 Sep 2018 13:48:33 +0200 (CEST) Date: Wed, 5 Sep 2018 13:48:33 +0200 From: Peter Zijlstra To: Sai Praneeth Prakhya Cc: linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org, ricardo.neri@intel.com, matt@codeblueprint.co.uk, Al Stone , Borislav Petkov , Ingo Molnar , Andy Lutomirski , Bhupesh Sharma , Thomas Gleixner , Ard Biesheuvel Subject: Re: [PATCH V3 3/5] x86/efi: Permanently save the EFI_MEMORY_MAP passed by the firmware Message-ID: <20180905114833.GW24082@hirez.programming.kicks-ass.net> References: <1536099149-12564-1-git-send-email-sai.praneeth.prakhya@intel.com> <1536099149-12564-4-git-send-email-sai.praneeth.prakhya@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1536099149-12564-4-git-send-email-sai.praneeth.prakhya@intel.com> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 04, 2018 at 03:12:27PM -0700, Sai Praneeth Prakhya wrote: > +void __init efi_save_original_memmap(void) > +{ > + efi_memory_desc_t *md; > + void *remapped_phys, *new_md; > + phys_addr_t new_phys, new_size; > + > + new_size = efi.memmap.desc_size * efi.memmap.nr_map; > + new_phys = efi_memmap_alloc(efi.memmap.nr_map); > + if (!new_phys) { > + pr_err("Failed to allocate new EFI memmap\n"); > + return; > + } > + > + remapped_phys = memremap(new_phys, new_size, MEMREMAP_WB); > + if (!remapped_phys) { > + pr_err("Failed to remap new EFI memmap\n"); > + __free_pages(pfn_to_page(PHYS_PFN(new_phys)), get_order(new_size)); > + return; > + } > + > + new_md = remapped_phys; > + for_each_efi_memory_desc(md) { > + memcpy(new_md, md, efi.memmap.desc_size); > + new_md += efi.memmap.desc_size; > + } Should we ioremap_prot(remapped_phys, new_size, PROT_NONE), here? Such that nobody can accidentally use this thing? > + original_memory_map.late = 1; > + original_memory_map.phys_map = new_phys; > + original_memory_map.map = remapped_phys; > + original_memory_map.nr_map = efi.memmap.nr_map; > + original_memory_map.desc_size = efi.memmap.desc_size; > + original_memory_map.map_end = remapped_phys + new_size; > + original_memory_map.desc_version = efi.memmap.desc_version; > + > + original_memory_map_present = true; > +} > +#endif /* CONFIG_EFI_WARN_ON_ILLEGAL_ACCESS */ > -- > 2.7.4 >