Need update to libbpf/bpftool for bpf_stream_vprintk() removal (kernel sha 0cecd492f516)

Need update to libbpf/bpftool for bpf_stream_vprintk() removal (kernel sha 0cecd492f516)

[Calvin Owens]

Hi Andrii,

Your libbpf github sync at [1] happened just before [2] was merged...
would you mind syncing that bpf_helpers.h change into libbpf/bpftool?

    In file included from skeleton/profiler.bpf.c:4:
    libbpf/include/bpf/bpf_helpers.h:318:12: error: conflicting types for 'bpf_stream_vprintk'
         318 | extern int bpf_stream_vprintk(int stream_id, const char *fmt__str, const void *args,
             |            ^
    ./vmlinux.h:128001:12: note: previous declaration is here
      128001 | extern int bpf_stream_vprintk(int stream_id, const char *fmt__str, const void *args, u32 len__sz) __weak __ksym;

I'm happy to send patches if I can help, but I'm guessing this is one of
those things that is easier to just do yourself with commit access...

Cheers,
Calvin

[2] https://github.com/libbpf/libbpf/commit/6ddc03d4fe0535ac0fb6c8525db31ac88a018ddd
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0cecd492f516

Re: Need update to libbpf/bpftool for bpf_stream_vprintk() removal (kernel sha 0cecd492f516)

[Quentin Monnet]

2026-03-09 10:57 UTC-0700 ~ Calvin Owens <calvin@wbinvd.org>
> Hi Andrii,
> 
> Your libbpf github sync at [1] happened just before [2] was merged...
> would you mind syncing that bpf_helpers.h change into libbpf/bpftool?
> 
>     In file included from skeleton/profiler.bpf.c:4:
>     libbpf/include/bpf/bpf_helpers.h:318:12: error: conflicting types for 'bpf_stream_vprintk'
>          318 | extern int bpf_stream_vprintk(int stream_id, const char *fmt__str, const void *args,
>              |            ^
>     ./vmlinux.h:128001:12: note: previous declaration is here
>       128001 | extern int bpf_stream_vprintk(int stream_id, const char *fmt__str, const void *args, u32 len__sz) __weak __ksym;


Hi, where did you observe that, please? I don't see it when compiling
bpftool from the main branch of the GitHub repo.


> I'm happy to send patches if I can help, but I'm guessing this is one of
> those things that is easier to just do yourself with commit access...
> 
> Cheers,
> Calvin
> 
> [2] https://github.com/libbpf/libbpf/commit/6ddc03d4fe0535ac0fb6c8525db31ac88a018ddd
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0cecd492f516


I take care of bpftool, my ideal workflow is to sync after libbpf has
been updated. Andrii, if you have a moment to do a libbpf sync, I'm
happy to follow up with bpftool.

Quentin

Re: Need update to libbpf/bpftool for bpf_stream_vprintk() removal (kernel sha 0cecd492f516)

[Calvin Owens]

On Monday 03/09 at 20:34 +0000, Quentin Monnet wrote:
> 2026-03-09 10:57 UTC-0700 ~ Calvin Owens <calvin@wbinvd.org>
> > Hi Andrii,
> > 
> > Your libbpf github sync at [1] happened just before [2] was merged...
> > would you mind syncing that bpf_helpers.h change into libbpf/bpftool?
> > 
> >     In file included from skeleton/profiler.bpf.c:4:
> >     libbpf/include/bpf/bpf_helpers.h:318:12: error: conflicting types for 'bpf_stream_vprintk'
> >          318 | extern int bpf_stream_vprintk(int stream_id, const char *fmt__str, const void *args,
> >              |            ^
> >     ./vmlinux.h:128001:12: note: previous declaration is here
> >       128001 | extern int bpf_stream_vprintk(int stream_id, const char *fmt__str, const void *args, u32 len__sz) __weak __ksym;
> 
> 
> Hi, where did you observe that, please? I don't see it when compiling
> bpftool from the main branch of the GitHub repo.

Hi Quentin,

Thanks for looking, apologies for not adding you to the initial mail.

It's bpftool-7.6.0 with libbpf-1.6.2 that is failing to build in my
case (with 7.0-rc kernels), exactly what is described here:

    https://github.com/libbpf/libbpf/issues/947

I think it was just "bad luck" that it missed Andrii's sync, it was
committed in the kernel 18 hours after his sync. But maybe I'm assuming
too much from the timing...

Calvin

> > I'm happy to send patches if I can help, but I'm guessing this is one of
> > those things that is easier to just do yourself with commit access...
> > 
> > Cheers,
> > Calvin
> > 
> > [2] https://github.com/libbpf/libbpf/commit/6ddc03d4fe0535ac0fb6c8525db31ac88a018ddd
> > [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0cecd492f516
> 
> 
> I take care of bpftool, my ideal workflow is to sync after libbpf has
> been updated. Andrii, if you have a moment to do a libbpf sync, I'm
> happy to follow up with bpftool.
> 
> Quentin

Re: Need update to libbpf/bpftool for bpf_stream_vprintk() removal (kernel sha 0cecd492f516)

[Quentin Monnet]

2026-03-09 16:01 UTC-0700 ~ Calvin Owens <calvin@wbinvd.org>
> On Monday 03/09 at 20:34 +0000, Quentin Monnet wrote:
>> 2026-03-09 10:57 UTC-0700 ~ Calvin Owens <calvin@wbinvd.org>
>>> Hi Andrii,
>>>
>>> Your libbpf github sync at [1] happened just before [2] was merged...
>>> would you mind syncing that bpf_helpers.h change into libbpf/bpftool?
>>>
>>>     In file included from skeleton/profiler.bpf.c:4:
>>>     libbpf/include/bpf/bpf_helpers.h:318:12: error: conflicting types for 'bpf_stream_vprintk'
>>>          318 | extern int bpf_stream_vprintk(int stream_id, const char *fmt__str, const void *args,
>>>              |            ^
>>>     ./vmlinux.h:128001:12: note: previous declaration is here
>>>       128001 | extern int bpf_stream_vprintk(int stream_id, const char *fmt__str, const void *args, u32 len__sz) __weak __ksym;
>>
>>
>> Hi, where did you observe that, please? I don't see it when compiling
>> bpftool from the main branch of the GitHub repo.
> 
> Hi Quentin,
> 
> Thanks for looking, apologies for not adding you to the initial mail.
> 
> It's bpftool-7.6.0 with libbpf-1.6.2 that is failing to build in my
> case (with 7.0-rc kernels), exactly what is described here:
> 
>     https://github.com/libbpf/libbpf/issues/947


Ok, reading your first message I thought the error was when compiling
bpftool itself. Now I get it, thanks.


> I think it was just "bad luck" that it missed Andrii's sync, it was
> committed in the kernel 18 hours after his sync. But maybe I'm assuming
> too much from the timing...


Ihor and Andrii synced the libbpf mirror a few hours ago, and I just
updated the bpftool repo, so you should be able to pull the fix from there.

Best regards,
Quentin