Re: [PATCH makedumpfile 0/9] Improvements to makedumpfile extensions, plus userspace stack tracing extension

Hi Kazu & Stephen,

Please check my comments on the patchset. For the reset of the patchset, LGTM.

Reviewed-by: Tao Liu <[email protected]>

On Wed, Aug 12, 2026 at 5:07 PM Tao Liu <[email protected]> wrote:
>
> Hi Kazu,
>
> On Wed, Aug 12, 2026 at 1:32 PM HAGIO KAZUHITO(萩尾　一仁)
> <[email protected]> wrote:
> >
> > Hi Tao,
> >
> > On 2026/08/11 15:11, Tao Liu wrote:
> >
> > >>>>> and Tao, please check if your extension can be rebased on this
> > >>>>> patchset.  and also if you agree the extension list, please provide
> > >>>>> the information.
> > >
> > > I have checked my extension to rebase on this patchset. The result is:
> > >
> > > 1) Rebase fails, but only due to conflicts within extensions/Makefile.
> > > These are small issues which would be very easy to fix.
> > > 2) Once 1 is fixed, after compile, my extension can work as expected.
> > > However this is a coincidence.  Because my extension takes callback
> > > as:
> > >
> > > int extension_callback(unsigned long pfn, const void *pcache)
> > > {
> > >          struct ft_page_info *cur = NULL;
> > >          return filter_page(pfn, &cur);
> > > }
> > >
> > > But this patchset changed the callback into:
> > > run_extension_callback(unsigned long pfn, const void *pcache, const
> > > struct pginfo *i)
> > >
> > > My extension works because it only takes pfn as parameter, and the
> > > handle_cbs[i]->cb() doesn't check function parameters. However, I
> > > don't think it is a major issue, once the modification on extension.c
> > > merged upstream, I can adjust the function signature of mine
> > > accordingly.
> >
> > Thank you for checking.  My main concern was the change in behavior,
> > particularly with compound pages.  If your extension works well after
> > some adjustments, that's good to hear.  I will merge the patch set later.
> >
> OK, sounds good!
>
> > >
> > >>>>
> > >>>> Sure, I will check for the rebase. In the meantime, will the
> > >>>> extensions to be maintained in one repo (e.g. makedumpfile extensions
> > >>>> repo, so everyone can PR to it), or they are maintained in each of
> > >>>> individual repos, and link them under
> > >>>> https://github.com/makedumpfile/makedumpfile/wiki#extensions?
> > >>>
> > >>> I am open to either. I would be willing to co-maintain an extensions
> > >>> repository with Tao, for example at github.com/makedumpfile/extensions,
> > >>> so that there is a common place to contribute. That is, if this
> > >>> arrangement would work for all?
> > >>>
> > >>> If we did create a common repository, I think we'd want to set up some
> > >>> expectations on the quality & maintenance. EG, some may be marked as
> > >>> "maintained" with a maintainer and a scope of maintenance (supported
> > >>> kernel versions, supported architectures, etc), and others as
> > >>> "unmaintained", where we just make sure that they build & run with
> > >>> makedumpfile, but don't validate their behavior on specific kernels or
> > >>> architectures.
> > >>>
> > >>> On the other hand, if it's preferable to stay separate, then I'm happy
> > >>> to find another place to maintain the userstack & elfheader extensions.
> > >>
> > >> I was thinking of separate repositories.  A single repository would be
> > >> fine, but for now I have no plans to create one within the makedumpfile
> > >> organization.
> > >>
> > >> (Looking back at crash extensions, some become obsolete quickly or
> > >> have very specific functionality, making it difficult for anyone
> > >> other than the original author to maintain.  For this reason, I think
> > >> it is best for the authors themselves to manage them.)
> > >
> > > Understood, extensions are designed to address one specific issue, and
> > > is easy to get outdated when makedumpfile/crash utility keeping
> > > following up the latest kernel, but extensions are often left behind
> > > due to low usage. Let's go with maintainling the extensions by each
> > > authors seperately and link them into
> > > https://github.com/makedumpfile/makedumpfile/wiki#extensions
> >
> > Thank you for your understanding.  for now, please let me know the
> > information of your extension once it's ready.
>
> Please check my extension link:
> https://github.com/liutgnu/mkdf-extension-amdgpu-mm-filtering
>
> Thanks,
> Tao Liu
> >
> > Thanks,
> > Kazu