Nicholas Piggin <npig...@gmail.com> writes: > diff --git a/arch/powerpc/Makefile.postlink b/arch/powerpc/Makefile.postlink > index 1725e64..b8fe12b 100644 > --- a/arch/powerpc/Makefile.postlink > +++ b/arch/powerpc/Makefile.postlink > @@ -24,6 +27,9 @@ endif > > vmlinux: FORCE > @true > +ifeq ($(CONFIG_PPC64),y)
You can just use: ifdef CONFIG_PPC64 > + $(call cmd,head_check) > +endif > ifeq ($(CONFIG_RELOCATABLE),y) > $(call if_changed,relocs_check) > endif > @@ -32,6 +38,7 @@ endif > @true > > clean: > + rm -f .tmp_symbols.txt > @true We shouldn't need the true anymore should we? > diff --git a/arch/powerpc/tools/head_check.sh > b/arch/powerpc/tools/head_check.sh > new file mode 100755 > index 0000000..9635fe7 > --- /dev/null > +++ b/arch/powerpc/tools/head_check.sh > @@ -0,0 +1,69 @@ > +#!/bin/sh We run this explicitly via $(CONFIG_SHELL), so having a shebang here is redundant and also a little confusing. I added "-x" here, to turn on tracing, but it doesn't take effect, so I think better to just drop the line. If anyone wants to run it manually they can just pass it to sh. > +# 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 > + > +# READ THIS > +# > +# If the build dies here, it's likely code in head_64.S or nearby is > +# referencing labels it can't reach, which results in the linker inserting > +# stubs without the assembler's knowledge. This can move code around in ways > +# that break the fixed location placement stuff (head-64.h). To debug, > +# disassemble the vmlinux and look for branch stubs (long_branch, plt_branch > +# etc) in the fixed section region (0 - 0x8000ish). Check what places are > +# calling those stubs. > +# > +# 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. Can you add: # 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="$2" > + > +nm "$vmlinux" | grep -e " T _stext$" -e " t start_first_256B$" -e " a > text_start$" -e " t start_text$" -m4 > .tmp_symbols.txt You don't use $nm there. > + > + > +vma=$(cat .tmp_symbols.txt | grep " T _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 0" > + echo "ERROR: see comments in arch/powerpc/tools/head_check.sh" This is blowing up for me with ppc64e_defconfig. It says: ERROR: start_text address is c000000000001100, should be c000000000000200 cheers
