qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
* [Qemu-devel] [PATCH v2] Fix QEMU build on OpenBSD on x86 archs
@ 2013-12-10  1:26 Brad Smith
  2013-12-10  7:07 ` Stefan Weil
  0 siblings, 1 reply; 7+ messages in thread
From: Brad Smith @ 2013-12-10  1:26 UTC (permalink / raw)
  To: qemu-devel

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 <brad@comstyle.com>
---

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)
 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 $(TARGET_DIR)$@")
 
 %.raw: %.img
 	$(call quiet-command,$(OBJCOPY) -O binary -j .text $< $@,"  Building $(TARGET_DIR)$@")

-- 
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.

^ permalink raw reply related	[flat|nested] 7+ messages in thread

* Re: [Qemu-devel] [PATCH v2] Fix QEMU build on OpenBSD on x86 archs
  2013-12-10  1:26 [Qemu-devel] [PATCH v2] Fix QEMU build on OpenBSD on x86 archs Brad Smith
@ 2013-12-10  7:07 ` Stefan Weil
  2013-12-10  7:48   ` Brad Smith
  0 siblings, 1 reply; 7+ messages in thread
From: Stefan Weil @ 2013-12-10  7:07 UTC (permalink / raw)
  To: Brad Smith, qemu-devel

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 <brad@comstyle.com>
> ---
>
> 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.

Stefan

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Qemu-devel] [PATCH v2] Fix QEMU build on OpenBSD on x86 archs
  2013-12-10  7:07 ` Stefan Weil
@ 2013-12-10  7:48   ` Brad Smith
  2013-12-10 18:42     ` Stefan Weil
  0 siblings, 1 reply; 7+ messages in thread
From: Brad Smith @ 2013-12-10  7:48 UTC (permalink / raw)
  To: Stefan Weil, qemu-devel

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 <brad@comstyle.com>
>> ---
>>
>> 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.

-- 
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Qemu-devel] [PATCH v2] Fix QEMU build on OpenBSD on x86 archs
  2013-12-10  7:48   ` Brad Smith
@ 2013-12-10 18:42     ` Stefan Weil
  2013-12-10 18:44       ` Stefan Weil
  0 siblings, 1 reply; 7+ messages in thread
From: Stefan Weil @ 2013-12-10 18:42 UTC (permalink / raw)
  To: Brad Smith, qemu-devel

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 <brad@comstyle.com>
>>> ---
>>>
>>> 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 <sw@weilnetz.de>


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).

Regards,
Stefan

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Qemu-devel] [PATCH v2] Fix QEMU build on OpenBSD on x86 archs
  2013-12-10 18:42     ` Stefan Weil
@ 2013-12-10 18:44       ` Stefan Weil
  2013-12-10 21:32         ` Brad Smith
  2013-12-11  0:41         ` Brad Smith
  0 siblings, 2 replies; 7+ messages in thread
From: Stefan Weil @ 2013-12-10 18:44 UTC (permalink / raw)
  To: Brad Smith, qemu-devel, qemu-stable

... 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 <brad@comstyle.com>
>>>> ---
>>>>
>>>> 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 <sw@weilnetz.de>
>
>
> 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).
>
> Regards,
> Stefan
>

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Qemu-devel] [PATCH v2] Fix QEMU build on OpenBSD on x86 archs
  2013-12-10 18:44       ` Stefan Weil
@ 2013-12-10 21:32         ` Brad Smith
  2013-12-11  0:41         ` Brad Smith
  1 sibling, 0 replies; 7+ messages in thread
From: Brad Smith @ 2013-12-10 21:32 UTC (permalink / raw)
  To: Stefan Weil, qemu-devel, 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 <brad@comstyle.com>
>>>>> ---
>>>>>
>>>>> 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 <sw@weilnetz.de>
>>
>>
>> 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.

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Qemu-devel] [PATCH v2] Fix QEMU build on OpenBSD on x86 archs
  2013-12-10 18:44       ` Stefan Weil
  2013-12-10 21:32         ` Brad Smith
@ 2013-12-11  0:41         ` Brad Smith
  1 sibling, 0 replies; 7+ messages in thread
From: Brad Smith @ 2013-12-11  0:41 UTC (permalink / raw)
  To: Stefan Weil, qemu-devel, qemu-stable

On 10/12/13 1:44 PM, Stefan Weil wrote:
> ... now with qemu-stable addressed - I had pressed "send" to early.

Ah, I usually send such requests separately with a commit hash after
it has been commited to master.

-- 
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.

^ permalink raw reply	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2013-12-11  0:42 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-12-10  1:26 [Qemu-devel] [PATCH v2] Fix QEMU build on OpenBSD on x86 archs Brad Smith
2013-12-10  7:07 ` Stefan Weil
2013-12-10  7:48   ` Brad Smith
2013-12-10 18:42     ` Stefan Weil
2013-12-10 18:44       ` Stefan Weil
2013-12-10 21:32         ` Brad Smith
2013-12-11  0:41         ` Brad Smith

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).