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=-9.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 8B6DDC55178 for ; Sun, 25 Oct 2020 17:24:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4998D208A9 for ; Sun, 25 Oct 2020 17:24:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="rrSDS/GH" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1417635AbgJYRYu (ORCPT ); Sun, 25 Oct 2020 13:24:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46692 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1415746AbgJYRYr (ORCPT ); Sun, 25 Oct 2020 13:24:47 -0400 Received: from mail-qt1-x841.google.com (mail-qt1-x841.google.com [IPv6:2607:f8b0:4864:20::841]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F31CAC061755; Sun, 25 Oct 2020 10:24:46 -0700 (PDT) Received: by mail-qt1-x841.google.com with SMTP id m65so5086540qte.11; Sun, 25 Oct 2020 10:24:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=PZFCyeKv5e8ADxosNdndjAJeNVY61tGhsC7YMDs2lLY=; b=rrSDS/GHYiQ/mJTLF/Bn4P7l35W697D0DhBeQ5VBoStO6fjKxe5XqJzYSjGyY/qlQ7 kK3gKLhTbglAZr9DBzKhgx1NH1/s71324/2xqdvYRVr6vJF3rtIMs03cFiipKteUDtuB 8QkJCzowu9QPaiqMAuZKvLO4LfTgnZ19hfA2zRZz8nOiDH73l4P6hphcKbWnqnC/x53X fT/3PNS9d2xMuqxUqVTjXfWxr9ymEmvxfRWaPQhg4yRxdF9mW5Po2KIBX+xtX92drOUk 6NuAbpZ3VayYNh48gl+RwFkTNU5OQz6FlOWFLUve0kgbx+wYwE1jfEmy5tAlxVl1yHYL JMog== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:date:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=PZFCyeKv5e8ADxosNdndjAJeNVY61tGhsC7YMDs2lLY=; b=lgCVKntqhfZGocxy1x7UgvmPvkxw/tS1bK5cbH7YAsytXOdLLVh7lL0dceOf8nNOLI 3x0t2hpeQ3fWEJwoDUO0zZCAV/M82nmGrBdzdQKRxO2FNAelwHKugXB2w5XCMT9r2pII Jfa+thRgdmazScuzhfQCAmwXtcv8q8yqSkW/xz/2+u1Gv+OddSNTOj+UaditEGnWPyYD v4JIGYwwYNQ3O1loIexv964WATTlOaPN+5yiGhuiV5rP3ojZPaUjCMcMkhi6PkUHPe7B 6I2dhcg8M4mVMwNx6E+JkMxNvCS3UvG+ymQo1Ve4AMbW2kzsLf3dnamR5LQgX564U/in f9xA== X-Gm-Message-State: AOAM531ItybZTmtT52y6qYw26M7A1e2rx8bIWPtHUfk4FV5TTnNb9uHX RgvoyGMyl5IXJiqmfBpdPr8= X-Google-Smtp-Source: ABdhPJxC3NAqB+fHxVRL6eVL3ig0Ov5daJGEA0uFVRn5BCwnN9nQnY+OAtQy/vfD71LJho6GqmLCbg== X-Received: by 2002:ac8:470a:: with SMTP id f10mr11440109qtp.246.1603646686066; Sun, 25 Oct 2020 10:24:46 -0700 (PDT) Received: from rani.riverdale.lan ([2001:470:1f07:5f3::b55f]) by smtp.gmail.com with ESMTPSA id s14sm593690qtb.25.2020.10.25.10.24.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 25 Oct 2020 10:24:45 -0700 (PDT) Sender: Arvind Sankar From: Arvind Sankar X-Google-Original-From: Arvind Sankar Date: Sun, 25 Oct 2020 13:24:43 -0400 To: Ard Biesheuvel Cc: Arvind Sankar , linux-efi , Linux Kernel Mailing List Subject: Re: [PATCH] efi/x86: Only copy the compressed kernel image in efi_relocate_kernel() Message-ID: <20201025172443.GA1222048@rani.riverdale.lan> References: <20201011142012.96493-1-nivedita@alum.mit.edu> <20201025161931.GA1119983@rani.riverdale.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Oct 25, 2020 at 05:28:06PM +0100, Ard Biesheuvel wrote: > On Sun, 25 Oct 2020 at 17:19, Arvind Sankar wrote: > > > > On Sun, Oct 11, 2020 at 10:20:12AM -0400, Arvind Sankar wrote: > > > 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 > > > > Ping > > > > I'll pick this up as a fix once the merge window closes. Thanks! > > > > --- > > > 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 > > >