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

[HAGIO KAZUHITO(萩尾 一仁)]

Hi Stephen, Tao,

On 2026/08/08 6:24, Stephen Brennan wrote:

>>> For user access, I'm thinking about adding makedumpfile extension list
>>> to its wiki page [1].  If you agree on this, please provide their
>>> information (extension name, author, link, description).
> 
> Here are mine:
> 
> - Extension Name: elfheader
>    Author: Stephen Brennan (my email)
>    Link: TBD - see below
>    Description: Includes the first page of any ELF file in the page cache
>    which is mapped to userspace. This inspired by bit 4 of
>    coredump_filter (see core(5)) for userspace core dumps. By including
>    the header of an ELF file, it's likely that a debugger can identify
>    its build ID and use that to find debugging information for it. This
>    helps when used in combination with the userstack extension.
> - Extension Name: userstack
>    Author: Stephen Brennan (my email)
>    Link: TBD - see below
>    Description: Attempts to include the memory pages for each userspace
>    thread's stack. This can make it possible to unwind userspace process
>    stacks using a vmcore, for example with drgn's contrib/pstack.py
>    script.

Thanks, I copied this to see how it looks.
https://github.com/makedumpfile/makedumpfile/wiki#extensions

Please let me know if there are any points of concern.

>>> * Could you add a description why PG_INCLUDE_HEAD is needed to the
>>> patch 7, as we cannot add the cover letter and the patch 9.
>>> (Text alone is ok, or you can use v2 just for the patch 7.)
> 
> Done as a text reply to patch 7.

Thanks, will use that.

>>> 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.
>>
>> 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.)

Thanks,
Kazu