Commit 58263ed7713e ("xen: add /buildinfo/config entry to hypervisor
filesystem") added a dependency to .config, but the hypervisor's build
config could be have another name via setting KCONFIG_CONFIG.

Fix that by using $(KCONFIG_CONFIG) instead. Additionally reference
the config file via $(XEN_ROOT) instead of a relative path.

Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
---
 xen/common/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/common/Makefile b/xen/common/Makefile
index 91581e1815..2799f6510c 100644
--- a/xen/common/Makefile
+++ b/xen/common/Makefile
@@ -75,7 +75,7 @@ obj-$(CONFIG_UBSAN) += ubsan/
 obj-$(CONFIG_NEEDS_LIBELF) += libelf/
 obj-$(CONFIG_HAS_DEVICE_TREE) += libfdt/
 
-config.gz: ../.config
+config.gz: $(XEN_ROOT)/xen/$(KCONFIG_CONFIG)
 	gzip -c $< >$@
 
 config_data.o: config.gz
-- 
2.26.2

On 02.06.2020 13:40, Juergen Gross wrote:
> --- a/xen/common/Makefile
> +++ b/xen/common/Makefile
> @@ -75,7 +75,7 @@ obj-$(CONFIG_UBSAN) += ubsan/
>  obj-$(CONFIG_NEEDS_LIBELF) += libelf/
>  obj-$(CONFIG_HAS_DEVICE_TREE) += libfdt/
>  
> -config.gz: ../.config
> +config.gz: $(XEN_ROOT)/xen/$(KCONFIG_CONFIG)

Looking at all pre-existing uses of KCONFIG_CONFIG this is the
first one assuming it holds a relative path. The doc also doesn't
indicate it can't be an absolute one.

Jan

On Tue, Jun 02, 2020 at 01:55:14PM +0200, Jan Beulich wrote:
> On 02.06.2020 13:40, Juergen Gross wrote:
> > --- a/xen/common/Makefile
> > +++ b/xen/common/Makefile
> > @@ -75,7 +75,7 @@ obj-$(CONFIG_UBSAN) += ubsan/
> >  obj-$(CONFIG_NEEDS_LIBELF) += libelf/
> >  obj-$(CONFIG_HAS_DEVICE_TREE) += libfdt/
> >  
> > -config.gz: ../.config
> > +config.gz: $(XEN_ROOT)/xen/$(KCONFIG_CONFIG)
> 
> Looking at all pre-existing uses of KCONFIG_CONFIG this is the
> first one assuming it holds a relative path. The doc also doesn't
> indicate it can't be an absolute one.

This is not an objection to this patch right?

Wei.

> 
> Jan

On 02.06.20 14:07, Wei Liu wrote:
> On Tue, Jun 02, 2020 at 01:55:14PM +0200, Jan Beulich wrote:
>> On 02.06.2020 13:40, Juergen Gross wrote:
>>> --- a/xen/common/Makefile
>>> +++ b/xen/common/Makefile
>>> @@ -75,7 +75,7 @@ obj-$(CONFIG_UBSAN) += ubsan/
>>>   obj-$(CONFIG_NEEDS_LIBELF) += libelf/
>>>   obj-$(CONFIG_HAS_DEVICE_TREE) += libfdt/
>>>   
>>> -config.gz: ../.config
>>> +config.gz: $(XEN_ROOT)/xen/$(KCONFIG_CONFIG)
>>
>> Looking at all pre-existing uses of KCONFIG_CONFIG this is the
>> first one assuming it holds a relative path. The doc also doesn't
>> indicate it can't be an absolute one.
> 
> This is not an objection to this patch right?

I can see his point.

In case KCONFIG_CONFIG is set to an absolute path the result won't
build.

The proper solution would be to test KCONFIG_CONFIG for being an
absolute path and do the prefixing of $(XEN_ROOT)/xen/ only if this
isn't the case.

I'll send V2 of this patch.


Juergen

On 02.06.2020 14:07, Wei Liu wrote:
> On Tue, Jun 02, 2020 at 01:55:14PM +0200, Jan Beulich wrote:
>> On 02.06.2020 13:40, Juergen Gross wrote:
>>> --- a/xen/common/Makefile
>>> +++ b/xen/common/Makefile
>>> @@ -75,7 +75,7 @@ obj-$(CONFIG_UBSAN) += ubsan/
>>>  obj-$(CONFIG_NEEDS_LIBELF) += libelf/
>>>  obj-$(CONFIG_HAS_DEVICE_TREE) += libfdt/
>>>  
>>> -config.gz: ../.config
>>> +config.gz: $(XEN_ROOT)/xen/$(KCONFIG_CONFIG)
>>
>> Looking at all pre-existing uses of KCONFIG_CONFIG this is the
>> first one assuming it holds a relative path. The doc also doesn't
>> indicate it can't be an absolute one.
> 
> This is not an objection to this patch right?

It is.

Jan