Problems when trying to build tools/testing/selftests

Problems when trying to build tools/testing/selftests

[Guenter Roeck]

Hi,

when trying to build tools/testing/selftests, I get a lot of warnings such as

mount-notify_test.c: In function ‘fanotify_fsmount’:
mount-notify_test.c:360:14: warning: implicit declaration of function ‘fsopen’; did you mean ‘fdopen’?

and subsequent build errors.

testing/selftests/filesystems/mount-notify/mount-notify_test.c:360: undefined reference to `fsopen'
/usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:363: undefined reference to `fsconfig'
/usr/bin/ld:tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:366: undefined reference to `fsmount'
/usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:371: undefined reference to `move_mount'

This does not just affect a single file, but several of them.

What am I missing ? Is there some magic needed to build the selftests ?

Thanks,
Guenter

Re: Problems when trying to build tools/testing/selftests

[Shuah]

On 12/2/25 22:20, Guenter Roeck wrote:
> Hi,
> 
> when trying to build tools/testing/selftests, I get a lot of warnings such as
> 
> mount-notify_test.c: In function ‘fanotify_fsmount’:
> mount-notify_test.c:360:14: warning: implicit declaration of function ‘fsopen’; did you mean ‘fdopen’?
> 
> and subsequent build errors.
> 
> testing/selftests/filesystems/mount-notify/mount-notify_test.c:360: undefined reference to `fsopen'
> /usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:363: undefined reference to `fsconfig'
> /usr/bin/ld:tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:366: undefined reference to `fsmount'
> /usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:371: undefined reference to `move_mount'
> 
> This does not just affect a single file, but several of them.
> 
> What am I missing ? Is there some magic needed to build the selftests ?

Not sure. It built fine for me on Linux 6.18 latest. Are you missing
a library possibly?

thanks,
-- Shuah

Re: Problems when trying to build tools/testing/selftests

[Randy Dunlap]

On 12/3/25 9:25 AM, Shuah wrote:
> On 12/2/25 22:20, Guenter Roeck wrote:
>> Hi,
>>
>> when trying to build tools/testing/selftests, I get a lot of warnings such as
>>
>> mount-notify_test.c: In function ‘fanotify_fsmount’:
>> mount-notify_test.c:360:14: warning: implicit declaration of function ‘fsopen’; did you mean ‘fdopen’?
>>
>> and subsequent build errors.
>>
>> testing/selftests/filesystems/mount-notify/mount-notify_test.c:360: undefined reference to `fsopen'
>> /usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:363: undefined reference to `fsconfig'
>> /usr/bin/ld:tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:366: undefined reference to `fsmount'
>> /usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:371: undefined reference to `move_mount'
>>
>> This does not just affect a single file, but several of them.
>>
>> What am I missing ? Is there some magic needed to build the selftests ?
> 
> Not sure. It built fine for me on Linux 6.18 latest. Are you missing
> a library possibly?

Guenter, did you follow Documentation/dev-tools/kselftest.rst?

Shuah, is that document what you recommend?

-- 
~Randy

Re: Problems when trying to build tools/testing/selftests

[Guenter Roeck]

On 12/3/25 09:55, Randy Dunlap wrote:
> 
> 
> On 12/3/25 9:25 AM, Shuah wrote:
>> On 12/2/25 22:20, Guenter Roeck wrote:
>>> Hi,
>>>
>>> when trying to build tools/testing/selftests, I get a lot of warnings such as
>>>
>>> mount-notify_test.c: In function ‘fanotify_fsmount’:
>>> mount-notify_test.c:360:14: warning: implicit declaration of function ‘fsopen’; did you mean ‘fdopen’?
>>>
>>> and subsequent build errors.
>>>
>>> testing/selftests/filesystems/mount-notify/mount-notify_test.c:360: undefined reference to `fsopen'
>>> /usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:363: undefined reference to `fsconfig'
>>> /usr/bin/ld:tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:366: undefined reference to `fsmount'
>>> /usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:371: undefined reference to `move_mount'
>>>
>>> This does not just affect a single file, but several of them.
>>>
>>> What am I missing ? Is there some magic needed to build the selftests ?
>>
>> Not sure. It built fine for me on Linux 6.18 latest. Are you missing
>> a library possibly?
> 
> Guenter, did you follow Documentation/dev-tools/kselftest.rst?
> 

The document says

To build the tests::

   $ make headers
   $ make -C tools/testing/selftests

which is what I did.

I did run

kselftest_deps.sh gcc

which tells me

FAIL: net/tcp_ao/Makefile dependency check: $(LIB)
FAIL: bpf/Makefile dependency check: $(LIBELF_LIBS)
FAIL: bpf/Makefile dependency check: $(PCAP_LIBS)
FAIL: net/netfilter/Makefile dependency check: $(MNL_LDLIBS)
FAIL: net/netfilter/Makefile dependency check: $(MNL_LDLIBS)
--------------------------------------------------------
Targets failed build dependency check on system:
bpf net
--------------------------------------------------------
Missing libraries system
$(LIB) $(LIBELF_LIBS) $(MNL_LDLIBS) $(PCAP_LIBS)

which doeesn't really help. For example, PCAP_LIBS seems to refer to libpcap,
and I have libpcap-dev installed on my system.

Unless I am missing something that doesn't explain the build failures.

Guenter

Re: Problems when trying to build tools/testing/selftests

[Shuah Khan]

On 12/3/25 14:01, Guenter Roeck wrote:
> On 12/3/25 09:55, Randy Dunlap wrote:
>>
>>
>> On 12/3/25 9:25 AM, Shuah wrote:
>>> On 12/2/25 22:20, Guenter Roeck wrote:
>>>> Hi,
>>>>
>>>> when trying to build tools/testing/selftests, I get a lot of warnings such as
>>>>
>>>> mount-notify_test.c: In function ‘fanotify_fsmount’:
>>>> mount-notify_test.c:360:14: warning: implicit declaration of function ‘fsopen’; did you mean ‘fdopen’?
>>>>
>>>> and subsequent build errors.
>>>>
>>>> testing/selftests/filesystems/mount-notify/mount-notify_test.c:360: undefined reference to `fsopen'
>>>> /usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:363: undefined reference to `fsconfig'
>>>> /usr/bin/ld:tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:366: undefined reference to `fsmount'
>>>> /usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:371: undefined reference to `move_mount'

This usually indicates missing libraries or header path
issues.

>>>>
>>>> This does not just affect a single file, but several of them.
>>>>
>>>> What am I missing ? Is there some magic needed to build the selftests ?
>>>
>>> Not sure. It built fine for me on Linux 6.18 latest. Are you missing
>>> a library possibly?
>>
>> Guenter, did you follow Documentation/dev-tools/kselftest.rst?
>>
> 
> The document says
> 
> To build the tests::
> 
>    $ make headers
>    $ make -C tools/testing/selftests
> 
> which is what I did.
> 
> I did run
> 
> kselftest_deps.sh gcc
> 
> which tells me
> 
> FAIL: net/tcp_ao/Makefile dependency check: $(LIB)
> FAIL: bpf/Makefile dependency check: $(LIBELF_LIBS)
> FAIL: bpf/Makefile dependency check: $(PCAP_LIBS)
> FAIL: net/netfilter/Makefile dependency check: $(MNL_LDLIBS)
> FAIL: net/netfilter/Makefile dependency check: $(MNL_LDLIBS)
> --------------------------------------------------------
> Targets failed build dependency check on system:
> bpf net
> --------------------------------------------------------
> Missing libraries system
> $(LIB) $(LIBELF_LIBS) $(MNL_LDLIBS) $(PCAP_LIBS)
> 
> which doeesn't really help. For example, PCAP_LIBS seems to refer to libpcap,
> and I have libpcap-dev installed on my system.
> 
> Unless I am missing something that doesn't explain the build failures.
> 

I ran "make kselftest-all" - mount-notify/mount-notify_test.c built
fine on Linux 6.18 - which repo are you trying on?

Can you try "make kselftest-all" and tell me what happens?

I also tried

make -C tools/testing/selftests

and

make -C tools/testing/selftests TARGETS="filesystems/mount-notify"

Which repo are you trying on?

thanks,
-- Shuah

Re: Problems when trying to build tools/testing/selftests

[Guenter Roeck]

On 12/3/25 13:51, Shuah Khan wrote:
> On 12/3/25 14:01, Guenter Roeck wrote:
>> On 12/3/25 09:55, Randy Dunlap wrote:
>>>
>>>
>>> On 12/3/25 9:25 AM, Shuah wrote:
>>>> On 12/2/25 22:20, Guenter Roeck wrote:
>>>>> Hi,
>>>>>
>>>>> when trying to build tools/testing/selftests, I get a lot of warnings such as
>>>>>
>>>>> mount-notify_test.c: In function ‘fanotify_fsmount’:
>>>>> mount-notify_test.c:360:14: warning: implicit declaration of function ‘fsopen’; did you mean ‘fdopen’?
>>>>>
>>>>> and subsequent build errors.
>>>>>
>>>>> testing/selftests/filesystems/mount-notify/mount-notify_test.c:360: undefined reference to `fsopen'
>>>>> /usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:363: undefined reference to `fsconfig'
>>>>> /usr/bin/ld:tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:366: undefined reference to `fsmount'
>>>>> /usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:371: undefined reference to `move_mount'
> 
> This usually indicates missing libraries or header path
> issues.
> 
>>>>>
>>>>> This does not just affect a single file, but several of them.
>>>>>
>>>>> What am I missing ? Is there some magic needed to build the selftests ?
>>>>
>>>> Not sure. It built fine for me on Linux 6.18 latest. Are you missing
>>>> a library possibly?
>>>
>>> Guenter, did you follow Documentation/dev-tools/kselftest.rst?
>>>
>>
>> The document says
>>
>> To build the tests::
>>
>>    $ make headers
>>    $ make -C tools/testing/selftests
>>
>> which is what I did.
>>
>> I did run
>>
>> kselftest_deps.sh gcc
>>
>> which tells me
>>
>> FAIL: net/tcp_ao/Makefile dependency check: $(LIB)
>> FAIL: bpf/Makefile dependency check: $(LIBELF_LIBS)
>> FAIL: bpf/Makefile dependency check: $(PCAP_LIBS)
>> FAIL: net/netfilter/Makefile dependency check: $(MNL_LDLIBS)
>> FAIL: net/netfilter/Makefile dependency check: $(MNL_LDLIBS)
>> --------------------------------------------------------
>> Targets failed build dependency check on system:
>> bpf net
>> --------------------------------------------------------
>> Missing libraries system
>> $(LIB) $(LIBELF_LIBS) $(MNL_LDLIBS) $(PCAP_LIBS)
>>
>> which doeesn't really help. For example, PCAP_LIBS seems to refer to libpcap,
>> and I have libpcap-dev installed on my system.
>>
>> Unless I am missing something that doesn't explain the build failures.
>>
> 
> I ran "make kselftest-all" - mount-notify/mount-notify_test.c built
> fine on Linux 6.18 - which repo are you trying on?
> 
> Can you try "make kselftest-all" and tell me what happens?
> 
> I also tried
> 
> make -C tools/testing/selftests
> 
> and
> 
> make -C tools/testing/selftests TARGETS="filesystems/mount-notify"
> 
> Which repo are you trying on?
> 

Mainline. Anyway, the problem turns out to be the glibc version. The missing functions
require glibc 2.36 or later, but I have glibc version 2.35 installed on the affected system.

Thanks,
Guenter

Re: Problems when trying to build tools/testing/selftests

[Shuah Khan]

On 12/3/25 15:01, Guenter Roeck wrote:
> On 12/3/25 13:51, Shuah Khan wrote:
>> On 12/3/25 14:01, Guenter Roeck wrote:
>>> On 12/3/25 09:55, Randy Dunlap wrote:
>>>>
>>>>
>>>> On 12/3/25 9:25 AM, Shuah wrote:
>>>>> On 12/2/25 22:20, Guenter Roeck wrote:
>>>>>> Hi,
>>>>>>
>>>>>> when trying to build tools/testing/selftests, I get a lot of warnings such as
>>>>>>
>>>>>> mount-notify_test.c: In function ‘fanotify_fsmount’:
>>>>>> mount-notify_test.c:360:14: warning: implicit declaration of function ‘fsopen’; did you mean ‘fdopen’?
>>>>>>
>>>>>> and subsequent build errors.
>>>>>>
>>>>>> testing/selftests/filesystems/mount-notify/mount-notify_test.c:360: undefined reference to `fsopen'
>>>>>> /usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:363: undefined reference to `fsconfig'
>>>>>> /usr/bin/ld:tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:366: undefined reference to `fsmount'
>>>>>> /usr/bin/ld: tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c:371: undefined reference to `move_mount'
>>
>> This usually indicates missing libraries or header path
>> issues.
>>
>>>>>>
>>>>>> This does not just affect a single file, but several of them.
>>>>>>
>>>>>> What am I missing ? Is there some magic needed to build the selftests ?
>>>>>
>>>>> Not sure. It built fine for me on Linux 6.18 latest. Are you missing
>>>>> a library possibly?
>>>>
>>>> Guenter, did you follow Documentation/dev-tools/kselftest.rst?
>>>>
>>>
>>> The document says
>>>
>>> To build the tests::
>>>
>>>    $ make headers
>>>    $ make -C tools/testing/selftests
>>>
>>> which is what I did.
>>>
>>> I did run
>>>
>>> kselftest_deps.sh gcc
>>>
>>> which tells me
>>>
>>> FAIL: net/tcp_ao/Makefile dependency check: $(LIB)
>>> FAIL: bpf/Makefile dependency check: $(LIBELF_LIBS)
>>> FAIL: bpf/Makefile dependency check: $(PCAP_LIBS)
>>> FAIL: net/netfilter/Makefile dependency check: $(MNL_LDLIBS)
>>> FAIL: net/netfilter/Makefile dependency check: $(MNL_LDLIBS)
>>> --------------------------------------------------------
>>> Targets failed build dependency check on system:
>>> bpf net
>>> --------------------------------------------------------
>>> Missing libraries system
>>> $(LIB) $(LIBELF_LIBS) $(MNL_LDLIBS) $(PCAP_LIBS)
>>>
>>> which doeesn't really help. For example, PCAP_LIBS seems to refer to libpcap,
>>> and I have libpcap-dev installed on my system.
>>>
>>> Unless I am missing something that doesn't explain the build failures.
>>>
>>
>> I ran "make kselftest-all" - mount-notify/mount-notify_test.c built
>> fine on Linux 6.18 - which repo are you trying on?
>>
>> Can you try "make kselftest-all" and tell me what happens?
>>
>> I also tried
>>
>> make -C tools/testing/selftests
>>
>> and
>>
>> make -C tools/testing/selftests TARGETS="filesystems/mount-notify"
>>
>> Which repo are you trying on?
>>
> 
> Mainline. Anyway, the problem turns out to be the glibc version. The missing functions
> require glibc 2.36 or later, but I have glibc version 2.35 installed on the affected system.
> 

Ah that makes sense.

thanks,
-- Shuah