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 1B653C2D0D1 for ; Sun, 29 Dec 2019 17:57:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E7C68227BF for ; Sun, 29 Dec 2019 17:57:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577642226; bh=CtXnZ4O/bMRkIkPF8BOSiIRqPkqxfuL3zIobpbcfuic=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=K7J8FwzH3bRuKS320PSYsgsq9k+u0U6QM/fPDXdpc9bL4bqw8o2zJJcB5zgPPbraI fM+qF4ojLH2GCLyaqP4zU/gRoUzStId2PaM5BgwHssGAcgWrQCLW1O17g4gMbfBoQA W4nE5mkpcIjHIhqovPcPHPWn1nMCi0dxWLNoq0Ww= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733185AbfL2R5E (ORCPT ); Sun, 29 Dec 2019 12:57:04 -0500 Received: from mail.kernel.org ([198.145.29.99]:47178 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733176AbfL2R5E (ORCPT ); Sun, 29 Dec 2019 12:57:04 -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 95932206A4; Sun, 29 Dec 2019 17:57:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577642223; bh=CtXnZ4O/bMRkIkPF8BOSiIRqPkqxfuL3zIobpbcfuic=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KpCXkdp7ntM8lDA4w4Qp68uoMLMcILcBFbl3ceFKfiFOQJ7SSTXYXjzp5UHnh2DcF D1VrXEcX+/gNK9GjWrn8QjbJu3xZIrnr2ZXoC6zJrld8GwVyjXn473nSotNa7+QrMY jzVfokKZVw1uTVG+RdVDFyIAwonVL3PIX1jQ3MlQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Masayoshi Mizuma , Bhupesh Sharma , Ard Biesheuvel , Andy Shevchenko , Arvind Sankar , linux-efi@vger.kernel.org, Ingo Molnar Subject: [PATCH 5.4 393/434] efi/memreserve: Register reservations as reserved in /proc/iomem Date: Sun, 29 Dec 2019 18:27:26 +0100 Message-Id: <20191229172728.441663267@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191229172702.393141737@linuxfoundation.org> References: <20191229172702.393141737@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: Ard Biesheuvel commit ab0eb16205b43ece4c78e2259e681ff3d645ea66 upstream. Memory regions that are reserved using efi_mem_reserve_persistent() are recorded in a special EFI config table which survives kexec, allowing the incoming kernel to honour them as well. However, such reservations are not visible in /proc/iomem, and so the kexec tools that load the incoming kernel and its initrd into memory may overwrite these reserved regions before the incoming kernel has a chance to reserve them from further use. Address this problem by adding these reservations to /proc/iomem as they are created. Note that reservations that are inherited from a previous kernel are memblock_reserve()'d early on, so they are already visible in /proc/iomem. Tested-by: Masayoshi Mizuma Tested-by: Bhupesh Sharma Signed-off-by: Ard Biesheuvel Reviewed-by: Bhupesh Sharma Cc: # v5.4+ Cc: Andy Shevchenko Cc: Arvind Sankar Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191206165542.31469-2-ardb@kernel.org Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- drivers/firmware/efi/efi.c | 28 ++++++++++++++++++++++++++-- 1 file changed, 26 insertions(+), 2 deletions(-) --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -970,6 +970,24 @@ static int __init efi_memreserve_map_roo return 0; } +static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size) +{ + struct resource *res, *parent; + + res = kzalloc(sizeof(struct resource), GFP_ATOMIC); + if (!res) + return -ENOMEM; + + res->name = "reserved"; + res->flags = IORESOURCE_MEM; + res->start = addr; + res->end = addr + size - 1; + + /* we expect a conflict with a 'System RAM' region */ + parent = request_resource_conflict(&iomem_resource, res); + return parent ? request_resource(parent, res) : 0; +} + int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) { struct linux_efi_memreserve *rsv; @@ -994,7 +1012,7 @@ int __ref efi_mem_reserve_persistent(phy rsv->entry[index].size = size; memunmap(rsv); - return 0; + return efi_mem_reserve_iomem(addr, size); } memunmap(rsv); } @@ -1004,6 +1022,12 @@ int __ref efi_mem_reserve_persistent(phy if (!rsv) return -ENOMEM; + rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K); + if (rc) { + free_page((unsigned long)rsv); + return rc; + } + /* * The memremap() call above assumes that a linux_efi_memreserve entry * never crosses a page boundary, so let's ensure that this remains true @@ -1020,7 +1044,7 @@ int __ref efi_mem_reserve_persistent(phy efi_memreserve_root->next = __pa(rsv); spin_unlock(&efi_mem_reserve_persistent_lock); - return 0; + return efi_mem_reserve_iomem(addr, size); } static int __init efi_memreserve_root_init(void)