From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753370AbcDRQnj (ORCPT ); Mon, 18 Apr 2016 12:43:39 -0400 Received: from mail-pf0-f178.google.com ([209.85.192.178]:36430 "EHLO mail-pf0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753010AbcDRQm1 (ORCPT ); Mon, 18 Apr 2016 12:42:27 -0400 From: Kees Cook To: Ingo Molnar Cc: Kees Cook , Yinghai Lu , Baoquan He , "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , x86@kernel.org, Andrew Morton , Andrey Ryabinin , Dmitry Vyukov , "H.J. Lu" , Josh Poimboeuf , Borislav Petkov , Andy Lutomirski , linux-kernel@vger.kernel.org Subject: [PATCH 4/6] x86, boot: Clarify purpose of functions in misc.c Date: Mon, 18 Apr 2016 09:42:13 -0700 Message-Id: <1460997735-24785-5-git-send-email-keescook@chromium.org> X-Mailer: git-send-email 2.6.3 In-Reply-To: <1460997735-24785-1-git-send-email-keescook@chromium.org> References: <1460997735-24785-1-git-send-email-keescook@chromium.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The function "decompress_kernel" now performs many more duties, so this patch renames it to "extract_kernel" and updates callers and comments. Additionally the file header comment for misc.c is improved to actually describe what is contained. Suggested-by: Ingo Molnar Signed-off-by: Kees Cook --- arch/x86/boot/compressed/head_32.S | 8 ++++---- arch/x86/boot/compressed/head_64.S | 4 ++-- arch/x86/boot/compressed/misc.c | 10 ++++++---- 3 files changed, 12 insertions(+), 10 deletions(-) diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S index 0256064da8da..26dd9df19a69 100644 --- a/arch/x86/boot/compressed/head_32.S +++ b/arch/x86/boot/compressed/head_32.S @@ -233,9 +233,9 @@ relocated: 2: /* - * Do the decompression, and jump to the new kernel.. + * Do the extraction, and jump to the new kernel.. */ - /* push arguments for decompress_kernel: */ + /* push arguments for extract_kernel: */ pushl $z_run_size /* size of kernel with .bss and .brk */ pushl $z_output_len /* decompressed length, end of relocs */ leal z_extract_offset_negative(%ebx), %ebp @@ -246,11 +246,11 @@ relocated: leal boot_heap(%ebx), %eax pushl %eax /* heap area */ pushl %esi /* real mode pointer */ - call decompress_kernel /* returns kernel location in %eax */ + call extract_kernel /* returns kernel location in %eax */ addl $28, %esp /* - * Jump to the decompressed kernel. + * Jump to the extracted kernel. */ xorl %ebx, %ebx jmp *%eax diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 86558a199139..d43c30ed89ed 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -408,7 +408,7 @@ relocated: 2: /* - * Do the decompression, and jump to the new kernel.. + * Do the extraction, and jump to the new kernel.. */ pushq %rsi /* Save the real mode argument */ movq $z_run_size, %r9 /* size of kernel with .bss and .brk */ @@ -419,7 +419,7 @@ relocated: movl $z_input_len, %ecx /* input_len */ movq %rbp, %r8 /* output target address */ movq $z_output_len, %r9 /* decompressed length, end of relocs */ - call decompress_kernel /* returns kernel location in %rax */ + call extract_kernel /* returns kernel location in %rax */ popq %r9 popq %rsi diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index 462dfbf7467b..0d69e809673a 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -1,8 +1,10 @@ /* * misc.c * - * This is a collection of several routines from gzip-1.0.3 - * adapted for Linux. + * This is a collection of several routines used to extract the kernel + * which includes KASLR relocation, decompression, ELF parsing, and + * relocation processing. Additionally included are the screen and serial + * output functions and related debugging support functions. * * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994 * puts by Nick Holloway 1993, better puts by Martin Mares 1995 @@ -383,7 +385,7 @@ static void parse_elf(void *output) free(phdrs); } -asmlinkage __visible void *decompress_kernel(void *rmode, memptr heap, +asmlinkage __visible void *extract_kernel(void *rmode, memptr heap, unsigned char *input_data, unsigned long input_len, unsigned char *output, @@ -412,7 +414,7 @@ asmlinkage __visible void *decompress_kernel(void *rmode, memptr heap, cols = boot_params->screen_info.orig_video_cols; console_init(); - debug_putstr("early console in decompress_kernel\n"); + debug_putstr("early console in extract_kernel\n"); free_mem_ptr = heap; /* Heap */ free_mem_end_ptr = heap + BOOT_HEAP_SIZE; -- 2.6.3