mirror of https://gitee.com/openkylin/linux.git
79 lines
2.9 KiB
Bash
79 lines
2.9 KiB
Bash
|
# Copyright © 2016 IBM Corporation
|
||
|
|
|
||
|
|
# This program is free software; you can redistribute it and/or
|
||
|
|
# modify it under the terms of the GNU General Public License
|
||
|
|
# as published by the Free Software Foundation; either version
|
||
|
|
# 2 of the License, or (at your option) any later version.
|
||
|
|
|
||
|
|
# This script checks the head of a vmlinux for linker stubs that
|
||
|
|
# break our placement of fixed-location code for 64-bit.
|
||
|
|
|
||
|
|
# based on relocs_check.pl
|
||
|
|
# Copyright © 2009 IBM Corporation
|
||
|
|
|
||
|
|
# NOTE!
|
||
|
|
#
|
||
|
|
# If the build dies here, it's likely code in head_64.S/exception-64*.S or
|
||
|
|
# nearby, is branching to labels it can't reach directly, which results in the
|
||
|
|
# linker inserting branch stubs. This can move code around in ways that break
|
||
|
|
# the fixed section calculations (head-64.h). To debug this, disassemble the
|
||
|
|
# vmlinux and look for branch stubs (long_branch, plt_branch, etc.) in the
|
||
|
|
# fixed section region (0 - 0x8000ish). Check what code is calling those stubs,
|
||
|
|
# and perhaps change so a direct branch can reach.
|
||
|
|
#
|
||
|
|
# A ".linker_stub_catch" section is used to catch some stubs generated by
|
||
|
|
# early .text code, which tend to get placed at the start of the section.
|
||
|
|
# If there are too many such stubs, they can overflow this section. Expanding
|
||
|
|
# it may help (or reducing the number of stub branches).
|
||
|
|
#
|
||
|
|
# Linker stubs use the TOC pointer, so even if fixed section code could
|
||
|
|
# tolerate them being inserted into head code, they can't be allowed in low
|
||
|
|
# level entry code (boot, interrupt vectors, etc) until r2 is set up. This
|
||
|
|
# could cause the kernel to die in early boot.
|
||
|
|
|
||
|
|
# Turn this on if you want more debug output:
|
||
|
|
# set -x
|
||
|
|
|
||
|
|
if [ $# -lt 2 ]; then
|
||
|
|
echo "$0 [path to nm] [path to vmlinux]" 1>&2
|
||
|
|
exit 1
|
||
|
|
fi
|
||
|
|
|
||
|
|
# Have Kbuild supply the path to nm so we handle cross compilation.
|
||
|
|
nm="$1"
|
||
|
|
vmlinux="$2"
|
||
|
|
|
||
|
|
# gcc-4.6-era toolchain make _stext an A (absolute) symbol rather than T
|
||
|
|
$nm "$vmlinux" | grep -e " [TA] _stext$" -e " t start_first_256B$" -e " a text_start$" -e " t start_text$" -m4 > .tmp_symbols.txt
|
||
|
|
|
||
|
|
|
||
|
|
vma=$(cat .tmp_symbols.txt | grep -e " [TA] _stext$" | cut -d' ' -f1)
|
||
|
|
|
||
|
|
expected_start_head_addr=$vma
|
||
|
|
|
||
|
|
start_head_addr=$(cat .tmp_symbols.txt | grep " t start_first_256B$" | cut -d' ' -f1)
|
||
|
|
|
||
|
|
if [ "$start_head_addr" != "$expected_start_head_addr" ]; then
|
||
|
|
echo "ERROR: head code starts at $start_head_addr, should be $expected_start_head_addr"
|
||
|
|
echo "ERROR: try to enable LD_HEAD_STUB_CATCH config option"
|
||
|
|
echo "ERROR: see comments in arch/powerpc/tools/head_check.sh"
|
||
|
|
|
||
|
|
exit 1
|
||
|
|
fi
|
||
|
|
|
||
|
|
top_vma=$(echo $vma | cut -d'0' -f1)
|
||
|
|
|
||
|
|
expected_start_text_addr=$(cat .tmp_symbols.txt | grep " a text_start$" | cut -d' ' -f1 | sed "s/^0/$top_vma/")
|
||
|
|
|
||
|
|
start_text_addr=$(cat .tmp_symbols.txt | grep " t start_text$" | cut -d' ' -f1)
|
||
|
|
|
||
|
|
if [ "$start_text_addr" != "$expected_start_text_addr" ]; then
|
||
|
|
echo "ERROR: start_text address is $start_text_addr, should be $expected_start_text_addr"
|
||
|
|
echo "ERROR: try to enable LD_HEAD_STUB_CATCH config option"
|
||
|
|
echo "ERROR: see comments in arch/powerpc/tools/head_check.sh"
|
||
|
|
|
||
|
|
exit 1
|
||
|
|
fi
|
||
|
|
|
||
|
|
rm -f .tmp_symbols.txt
|