[External] Re: Question - Livepatch/Kprobe Coexistence on Ftrace-enabled Functions (Ubuntu kernel based on Linux stable 5.15.30)

[Song Liu]

On Mon, Oct 20, 2025 at 12:10 PM Andrey Grodzovsky
<andrey.grodzovsky at crowdstrike.com> wrote:
[...]
> Seems reasonable to me, we are simply cleaning the entry on failure so
> we don't encounter it late anymore.
> So I will apply this patch ONLY and retest - correct ?

Right, we only need this small change.

> Another question - it seems you found where it broke ? I saw 'Cc:
> stable at vger.kernel.org # v6.6+' in your prev. patch.'
> If so , can you please point me to the offending patch so I add this to
> my records of my discovery work of bpf coexistence
> livepatching ?

The commit that causing the issue was in the Fixes tag:

Fixes: d05cb470663a ("ftrace: Fix modification of direct_function hash
while in use")

Thanks,
Song