From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37565) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VqUvJ-0000v2-Sk for qemu-devel@nongnu.org; Tue, 10 Dec 2013 16:32:59 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VqUvI-0000Cd-80 for qemu-devel@nongnu.org; Tue, 10 Dec 2013 16:32:57 -0500 Received: from speedy.comstyle.com ([2001:470:1d:8c::2]:1280 helo=mail.comstyle.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VqUvI-0000B3-1M for qemu-devel@nongnu.org; Tue, 10 Dec 2013 16:32:56 -0500 Message-ID: <52A78880.4050505@comstyle.com> Date: Tue, 10 Dec 2013 16:32:48 -0500 From: Brad Smith MIME-Version: 1.0 References: <20131210012628.GC28299@rox.home.comstyle.com> <52A6BDC8.1000209@weilnetz.de> <52A6C733.2030608@comstyle.com> <52A760A2.9020705@weilnetz.de> <52A760FD.1020302@weilnetz.de> In-Reply-To: <52A760FD.1020302@weilnetz.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2] Fix QEMU build on OpenBSD on x86 archs List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Weil , qemu-devel@nongnu.org, qemu-stable On 10/12/13 1:44 PM, Stefan Weil wrote: > ... now with qemu-stable addressed - I had pressed "send" to early. > > Stefan > > > Am 10.12.2013 19:42, schrieb Stefan Weil: >> Am 10.12.2013 08:48, schrieb Brad Smith: >>> On 10/12/13 2:07 AM, Stefan Weil wrote: >>>> Am 10.12.2013 02:26, schrieb Brad Smith: >>>>> This resolves the build issue with building the ROMs on OpenBSD on >>>>> x86 archs. >>>>> As of OpenBSD 5.3 the compiler builds PIE binaries by default and >>>>> thus the >>>>> whole OS/packages and so forth. The ROMs need to have PIE disabled. >>>>> This >>>>> is my initial attempt at trying to get somehting upstream so that QEMU >>>>> both builds out of the box and to resolve the build issue with the >>>>> buildbots that has been around for awhile. We have a patch in our ports >>>>> tree but it is just the flags hardcoded into the Makefile which >>>>> obviously >>>>> is not appropriate for upstream. >>>>> >>>>> From the OpenBSD buildbots.. >>>>> Building optionrom/multiboot.img >>>>> ld: multiboot.o: relocation R_X86_64_16 can not be used when making >>>>> a shared object; recompile with -fPIC >>>>> >>>>> >>>>> Signed-off by: Brad Smith >>>>> --- >>>>> >>>>> Changes in v2: >>>>> * Fix '==' is not portable syntax. >>>>> >>>>> >>>>> diff --git a/configure b/configure >>>>> index 508f6a5..6d84885 100755 >>>>> --- a/configure >>>>> +++ b/configure >>>>> @@ -1342,6 +1342,10 @@ EOF >>>>> if compile_prog "-fPIE -DPIE" "-pie"; then >>>>> QEMU_CFLAGS="-fPIE -DPIE $QEMU_CFLAGS" >>>>> LDFLAGS="-pie $LDFLAGS" >>>>> + if test "$targetos" = OpenBSD; then >>>>> + CC_NOPIE="-fno-pie" >>>>> + LD_NOPIE="-nopie" >>>>> + fi >>>>> pie="yes" >>>>> if compile_prog "" "-Wl,-z,relro -Wl,-z,now" ; then >>>>> LDFLAGS="-Wl,-z,relro -Wl,-z,now $LDFLAGS" >>>>> @@ -4307,6 +4311,8 @@ if test "$gcov" = "yes" ; then >>>>> echo "CONFIG_GCOV=y" >> $config_host_mak >>>>> echo "GCOV=$gcov_tool" >> $config_host_mak >>>>> fi >>>>> +echo "CC_NOPIE=$CC_NOPIE" >> $config_host_mak >>>>> +echo "LD_NOPIE=$LD_NOPIE" >> $config_host_mak >>>>> >>>>> # use included Linux headers >>>>> if test "$linux" = "yes" ; then >>>>> diff --git a/pc-bios/optionrom/Makefile b/pc-bios/optionrom/Makefile >>>>> index 57d8bd0..0b35000 100644 >>>>> --- a/pc-bios/optionrom/Makefile >>>>> +++ b/pc-bios/optionrom/Makefile >>>>> @@ -12,6 +12,7 @@ $(call set-vpath, $(SRC_PATH)/pc-bios/optionrom) >>>>> CFLAGS := -Wall -Wstrict-prototypes -Werror -fomit-frame-pointer >>>>> -fno-builtin >>>>> CFLAGS += -I$(SRC_PATH) >>>>> CFLAGS += $(call cc-option, $(CFLAGS), -fno-stack-protector) >>>>> +CFLAGS += $(CC_NOPIE) >>>> Would it be possible to add -fno-pie unconditionally here ... >>>> >>>> >>>>> QEMU_CFLAGS = $(CFLAGS) >>>>> >>>>> build-all: multiboot.bin linuxboot.bin kvmvapic.bin >>>>> @@ -20,7 +21,7 @@ build-all: multiboot.bin linuxboot.bin kvmvapic.bin >>>>> .SECONDARY: >>>>> >>>>> %.img: %.o >>>>> - $(call quiet-command,$(LD) -Ttext 0 -e _start -s -o $@ $<," >>>>> Building $(TARGET_DIR)$@") >>>>> + $(call quiet-command,$(LD) $(LD_NOPIE) -Ttext 0 -e _start -s -o >>>>> $@ $<," Building $(TARGET_DIR)$@") >>>>> >>>> >>>> ... and use -nopie here? I tried it in my Linux build environment, and >>>> it seems to work. >>>> >>>> Then no changes to file configure are needed. >>> The linker flag definitely does not exist everywhere so that would >>> break the build on other OS/toolchain combinations; for example stock >>> binutils does not have this flag. I would not have bothered going this >>> route if I didn't see having the flags hard coded as causing a problem. >>> >> >> Thank you for your explanation. I cc your patch to qemu-stable because >> fixing QEMU 1.7 for OpenBSD might be a good idea, too. >> >> Reviewed-by: Stefan Weil >> >> >> If other hosts beside OpenBSD will need thismodification in the future, >> I suggest modified code like this: >> >> if compile_prog "-fPIE -DPIE" "-pie"; then >> QEMU_CFLAGS="-fPIE -DPIE $QEMU_CFLAGS" >> LDFLAGS="-pie $LDFLAGS" >> # [...] >> fi >> >> if compile_prog "-fno-pie" "-nopie"; then >> CFLAGS_NOPIE="-fno-pie" >> LDFLAGS_NOPIE="-nopie" >> fi >> >> (separate if blocks in configure and use CFLAGS_NOPIE, LDFLAGS_NOPIE >> instead of CC_NOPIE, LD_NOPIE, this also needs a modified Makefile). Well if you want to use CFLAGS_NOPIE and LDFLAGS_NOPIE now I can do so. The variable names are not set in stone and I was just trying to come up with an idea of how to do this and see how it goes through review. -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.