[meta-virtualization] [PATCH 1/4] xen: drop patch that upstream says is wrong

[Nathan Rossi]

On Fri, Aug 28, 2015 at 1:24 PM, Doug Goldstein <cardoe at cardoe.com> wrote:
> On Thu, Aug 27, 2015 at 3:05 AM, Nathan Rossi <nathan at nathanrossi.com> wrote:
>> On Thu, Aug 27, 2015 at 8:18 AM, Doug Goldstein <cardoe at cardoe.com> wrote:
>>> On Tue, Aug 25, 2015 at 1:44 AM, Nathan Rossi <nathan at nathanrossi.com> wrote:
>>>> On Tue, Aug 25, 2015 at 6:26 AM, Doug Goldstein <cardoe at cardoe.com> wrote:
>>>>> Per upstream its not correct to always force -mfpmath=387 to work around
>>>>> the -mno-sse flags. Instead strip out -mfpmath=sse that Yocto injects
>>>>> for certain BSPs.
>>>>> ---
>>>>>  ...xen-x86-Fix-up-rules-when-forcing-mno-sse.patch | 28 ----------------------
>>>>>  recipes-extended/xen/xen.inc                       |  5 ++++
>>>>>  recipes-extended/xen/xen_4.5.0.bb                  |  1 -
>>>>>  3 files changed, 5 insertions(+), 29 deletions(-)
>>>>>  delete mode 100644 recipes-extended/xen/files/xen-x86-Fix-up-rules-when-forcing-mno-sse.patch
>>>>>
>>>>> diff --git a/recipes-extended/xen/files/xen-x86-Fix-up-rules-when-forcing-mno-sse.patch b/recipes-extended/xen/files/xen-x86-Fix-up-rules-when-forcing-mno-sse.patch
>>>>> deleted file mode 100644
>>>>> index 4c3e297..0000000
>>>>> --- a/recipes-extended/xen/files/xen-x86-Fix-up-rules-when-forcing-mno-sse.patch
>>>>> +++ /dev/null
>>>>> @@ -1,28 +0,0 @@
>>>>> -From: Nathan Rossi <nathan.rossi at xilinx.com>
>>>>> -Subject: [PATCH] xen/x86: Fix up rules when forcing -mno-sse
>>>>> -
>>>>> -* When forcing -mno-sse specify -mfpmath=387 to avoid the fallback
>>>>> -  warning
>>>>> -
>>>>> -Signed-off-by: Nathan Rossi <nathan.rossi at xilinx.com>
>>>>> -Upstream-Status: Not-Submitted
>>>>> ----
>>>>> - xen/arch/x86/Rules.mk | 2 +-
>>>>> - 1 file changed, 1 insertion(+), 1 deletion(-)
>>>>> -
>>>>> -diff --git a/xen/arch/x86/Rules.mk b/xen/arch/x86/Rules.mk
>>>>> -index 6775cb5..03848f7 100644
>>>>> ---- a/xen/arch/x86/Rules.mk
>>>>> -+++ b/xen/arch/x86/Rules.mk
>>>>> -@@ -42,7 +42,7 @@ x86 := y
>>>>> - x86_32 := n
>>>>> - x86_64 := y
>>>>> -
>>>>> --CFLAGS += -mno-red-zone -mno-sse -fpic
>>>>> -+CFLAGS += -mno-red-zone -mno-sse -fpic -mfpmath=387
>>>>> - CFLAGS += -fno-asynchronous-unwind-tables
>>>>> - # -fvisibility=hidden reduces -fpic cost, if it's available
>>>>> - ifneq ($(call cc-option,$(CC),-fvisibility=hidden,n),n)
>>>>> ---
>>>>> -2.1.1
>>>>> -
>>>>> diff --git a/recipes-extended/xen/xen.inc b/recipes-extended/xen/xen.inc
>>>>> index 432bf4d..c7a2347 100644
>>>>> --- a/recipes-extended/xen/xen.inc
>>>>> +++ b/recipes-extended/xen/xen.inc
>>>>> @@ -12,6 +12,11 @@ inherit autotools-brokensep gettext setuptools update-rc.d systemd
>>>>>
>>>>>  require xen-arch.inc
>>>>>
>>>>> +# Xen uses hardcodes the use of -mno-sse which conflicts -mfpmath=sse
>>>>> +# The issue arises from certain Yocto machine BSPs injecting -mfpmath=sse
>>>>> +# into the package's CFLAGS so we need to strip that
>>>>> +TUNE_CCARGS := "${@oe_filter_out('-mfpmath=sse', '${TUNE_CCARGS}', d)}"
>>>>
>>>> Just curious, filtering out that flag will also affect the building of
>>>> for example the target user-space tools no? is that problematic or do
>>>> other SSE related flags (for those BSPs) cause the use of this fpmath
>>>> setting regardless?
>>>>
>>>> Regards,
>>>> Nathan
>>>
>>> Yes you are correct. The existing patch was more targeted. However
>>> while the tools are built a lot of them aren't used.
>>> meta-virtualization pulls in its own QEMU and firmware blobs. The
>>> default in this case is -mfpmath=sse,387 so it won't really affect
>>> anything. But you are probably right this patch should be dropped and
>>> the existing path should be used. I'll approach this from the Xen side
>>> again.
>>
>> Another way to handle this if there is no consensus from the Xen side
>> is to setup the recipe to build different make targets separately.
>> Essentially doing the runmake for the hypervisor with CFLAGS setup
>> filtered and then building the other targets without modifying the
>> CFLAGS.
>>
>> Regards,
>> Nathan
>>
>
> That could work. I don't know how to do that in Yocto yet
> unfortunately. I do know the targets:
>
> make dist-xen -> compiles the hypervisor
> make dist-tools -> compiles the tools (libxl, qemu, etc)
> make install-xen -> depends on dist-xen and installs it to ${D}
> make install-tools -> depends on dist-tools but unfortunately always
> recompiles some items and installs to ${D}
>
> Any chance you you point me in the right direction or what doc would
> educate me on how to split up the make call?

There are a few in oe-core that have split compile/install make steps.
Search for "oe_runmake" and you will see any that manually override
the running of make for compile/install. But as an example
u-boot-mkimage does two make steps for compilation.

https://github.com/openembedded/openembedded-core/blob/3143920c541b55b543b9dcc12b18af4e0e4b7ae1/meta/recipes-bsp/u-boot/u-boot-mkimage_2015.07.bb#L21

Regards,
Nathan

>
> --
> Doug
>
>
>>>
>>> --
>>> Doug
>>>
>>>
>>>>
>>>>> +
>>>>>  PACKAGECONFIG ??= " \
>>>>>      sdl \
>>>>>      ${@bb.utils.contains('DISTRO_FEATURES', 'systemd', 'systemd', '', d)} \
>>>>> diff --git a/recipes-extended/xen/xen_4.5.0.bb b/recipes-extended/xen/xen_4.5.0.bb
>>>>> index 6c17b90..a5f03f3 100644
>>>>> --- a/recipes-extended/xen/xen_4.5.0.bb
>>>>> +++ b/recipes-extended/xen/xen_4.5.0.bb
>>>>> @@ -2,7 +2,6 @@ require xen.inc
>>>>>
>>>>>  SRC_URI = " \
>>>>>      http://bits.xensource.com/oss-xen/release/${PV}/xen-${PV}.tar.gz \
>>>>> -    file://xen-x86-Fix-up-rules-when-forcing-mno-sse.patch \
>>>>>      "
>>>>>
>>>>>  SRC_URI[md5sum] = "9bac43d2419d05a647064d9253bb03fa"
>>>>> --
>>>>> 2.1.4
>>>>>
>>>
>>>
>>>
>>> --
>>> Doug Goldstein
>
>
>
> --
> Doug Goldstein