Re: [OE-core] [PATCH 1/4] lttng-modules: update from 2.15.2 to 2.16.0-rc2

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Mon, 2026-08-17 at 14:05 +0300, Mikko Rapeli wrote:
> Hi,
> 
> On Fri, Aug 14, 2026 at 08:50:20AM -0400, Bruce Ashfield wrote:
> > On Fri, Aug 14, 2026 at 7:27 AM Mikko Rapeli <mikko.rapeli@linaro.org> wrote:
> > > On Fri, Aug 14, 2026 at 11:48:32AM +0100, Richard Purdie wrote:
> > > > On Fri, 2026-08-14 at 09:48 +0300, Mikko Rapeli via lists.openembedded.org wrote:
> > > > > To support kernel version 7.2. Fixes build error:
> > > > > 
> > > > > > lttng-syscalls.c: In function 'lttng_syscall_event_enabler_create_event':
> > > > > > lttng-syscalls.c:612:17: error: implicit declaration of function 'strncpy' [-Wimplicit-function-declaration]
> > > > > >   612 |                 strncpy(ev.name, desc->event_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1);
> > > > > >       |                 ^~~~~~~
> > > > > > lttng-syscalls.c:101:1: note: include '<string.h>' or provide a declaration of 'strncpy'
> > > > > >   100 | #include <instrumentation/syscalls/syscalls_unknown.h>
> > > > > >   +++ |+#include <string.h>
> > > > > >   101 | #undef TRACE_SYSTEM
> > > > > > lttng-syscalls.c:612:17: warning: incompatible implicit declaration of built-in function 'strncpy' [-Wbuiltin-declaration-mismatch]
> > > > > >   612 |                 strncpy(ev.name, desc->event_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1);
> > > > > >       |                 ^~~~~~~
> > > > > > lttng-syscalls.c:612:17: note: include '<string.h>' or provide a declaration of 'strncpy'
> > > > > > lttng-syscalls.c:704:17: warning: incompatible implicit declaration of built-in function 'strncpy' [-Wbuiltin-declaration-mismatch]
> > > > > >   704 |                 strncpy(ev.name, desc->event_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1);
> > > > > >       |                 ^~~~~~~
> > > > > > lttng-syscalls.c:704:17: note: include '<string.h>' or provide a declaration of 'strncpy'
> > > > > 
> > > > > Signed-off-by: Mikko Rapeli <mikko.rapeli@linaro.org>
> > > > > ---
> > > > >  .../{lttng-modules_2.15.2.bb => lttng-modules_2.16.0-rc2.bb} | 5 +++--
> > > > >  1 file changed, 3 insertions(+), 2 deletions(-)
> > > > >  rename meta/recipes-kernel/lttng/{lttng-modules_2.15.2.bb => lttng-modules_2.16.0-rc2.bb} (94%)
> > > > 
> > > > This probably needs to have a PV of 2.16.0~rc2 else the version sorting
> > > > when we upgrade to the release won't work...
> > > 
> > > Then the version is different compared to upstream tags. For CVEs I can set
> > > CVE_VERSION.
> > > 
> > > > Do we know how far off the final release is?
> > > 
> > > Honestly I don't know. Past releases seem to have around six weeks between
> > > last release candidate and actual release. v2.16.0-rc1 was tagged 7 weeks ago,
> > > v2.16.0-rc2 just two weeks ago so feels like it is quite close now.
> > 
> > That's why I've always avoided the lttng-modules -rc releases and have opted
> > to just cherry-pick the patches supporting the newer kernels when I go through
> > an uprev cycle.
> > 
> > That being said, the -rc isn't any riskier than that approach, I just don't like
> > timing their release.
> 
> Digging a bit more into this I found that the needed patches are also in upstream 2.15 stable
> branch pending release. I will pick those separately to current 2.15 recipe and they can be
> dropped when new point release update is done.

Ok, that sounds better than the versioning pain with the rc2.

I did check with Mathieu and it looks like the next 2.15 stable and the
2.16 releases will be in 1-2 weeks FWIW.

Cheers,

Richard