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=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 C3CE4C433DF for ; Sun, 11 Oct 2020 14:20:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 872B520781 for ; Sun, 11 Oct 2020 14:20:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730144AbgJKOUP (ORCPT ); Sun, 11 Oct 2020 10:20:15 -0400 Received: from mail-qv1-f65.google.com ([209.85.219.65]:34847 "EHLO mail-qv1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725863AbgJKOUO (ORCPT ); Sun, 11 Oct 2020 10:20:14 -0400 Received: by mail-qv1-f65.google.com with SMTP id cv1so7176393qvb.2; Sun, 11 Oct 2020 07:20:14 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=dWyWLnrnb2GKJhVjWNu3IOOiUQzNVrzCmOlIX/sAMcY=; b=GJPlKJua3KDevZdfJUVtjmT8HhiLLcw0xoUzMvLyiSpdFekrhfV3eB9jeFM5dbcBNq 0jBWudI373iUP3CPhd7BrWWUyKpKhuSix9vGVF4PhA2YI+/4oYdef8xoHQ3BCyaxTSOt xGT0SP1N8zhalQRo5M34YVIf6yOnj3/DGNG8RNrOGUgpP1QADS0pew1wRqriWxr0Yfb6 jdoQwojmj95dsNXib6i3O2iUeVruxJt8hQHzjM/yad5kYyZF1yvohfFOAzbDBwXDXLDq K3a7ucJpIxASeCnYrBsm48xSVfDFkqkGeSubvoOe31MpA5/szTVWK0evvUSYBrQGSWTf go7g== X-Gm-Message-State: AOAM532Gg9zEIbCZ+ZNaqqUfjy6pdXhyQn57Ua/7X3VI4xqxRSy2uD+d JaItZJuIX15Vm5uz3Y7vRetvbMp84RoB2w== X-Google-Smtp-Source: ABdhPJysz1vjU2SOWAzZar8gr++J9DH9Y2B1ACIS+9wquQ1pZUwbr0Mv3hMx0YHqjhwW20fMy301JA== X-Received: by 2002:a05:6214:17d3:: with SMTP id cu19mr4799236qvb.12.1602426013403; Sun, 11 Oct 2020 07:20:13 -0700 (PDT) Received: from rani.riverdale.lan ([2001:470:1f07:5f3::b55f]) by smtp.gmail.com with ESMTPSA id f189sm10175147qkd.20.2020.10.11.07.20.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 11 Oct 2020 07:20:12 -0700 (PDT) From: Arvind Sankar To: linux-efi@vger.kernel.org Cc: linux-kernel@vger.kernel.org Subject: [PATCH] efi/x86: Only copy the compressed kernel image in efi_relocate_kernel() Date: Sun, 11 Oct 2020 10:20:12 -0400 Message-Id: <20201011142012.96493-1-nivedita@alum.mit.edu> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org The image_size argument to efi_relocate_kernel() is currently specified as init_size, but this is unnecessarily large. The compressed kernel is much smaller, in fact, its image only extends up to the start of _bss, since at this point, the .bss section is still uninitialized. Depending on compression level, this can reduce the amount of data copied by 4-5x. Signed-off-by: Arvind Sankar --- drivers/firmware/efi/libstub/x86-stub.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c index 3672539cb96e..f14c4ff5839f 100644 --- a/drivers/firmware/efi/libstub/x86-stub.c +++ b/drivers/firmware/efi/libstub/x86-stub.c @@ -715,8 +715,11 @@ unsigned long efi_main(efi_handle_t handle, (IS_ENABLED(CONFIG_X86_32) && buffer_end > KERNEL_IMAGE_SIZE) || (IS_ENABLED(CONFIG_X86_64) && buffer_end > MAXMEM_X86_64_4LEVEL) || (image_offset == 0)) { + extern char _bss[]; + status = efi_relocate_kernel(&bzimage_addr, - hdr->init_size, hdr->init_size, + (unsigned long)_bss - bzimage_addr, + hdr->init_size, hdr->pref_address, hdr->kernel_alignment, LOAD_PHYSICAL_ADDR); -- 2.26.2