Re: [PATCH 00/16] MAINTAINERS: Include GDB scripts under their relevant subsystems

[Jan Kara <jack@suse.cz>]

On Thu 26-06-25 09:39:36, Florian Fainelli wrote:
> On 6/26/25 09:17, Liam R. Howlett wrote:
> > * Florian Fainelli <florian.fainelli@broadcom.com> [250625 19:13]:
> > > Linux has a number of very useful GDB scripts under scripts/gdb/linux/*
> > > that provide OS awareness for debuggers and allows for debugging of a
> > > variety of data structures (lists, timers, radix tree, mapletree, etc.)
> > > as well as subsystems (clocks, devices, classes, busses, etc.).
> > > 
> > > These scripts are typically maintained in isolation from the subsystem
> > > that they parse the data structures and symbols of, which can lead to
> > > people playing catch up with fixing bugs or updating the script to work
> > > with updates made to the internal APIs/objects etc. Here are some
> > > recents examples:
> > > 
> > > https://lore.kernel.org/all/20250601055027.3661480-1-tony.ambardar@gmail.com/
> > > https://lore.kernel.org/all/20250619225105.320729-1-florian.fainelli@broadcom.com/
> > > https://lore.kernel.org/all/20250625021020.1056930-1-florian.fainelli@broadcom.com/
> > > 
> > > This patch series is intentionally split such that each subsystem
> > > maintainer can decide whether to accept the extra
> > > review/maintenance/guidance that can be offered when GDB scripts are
> > > being updated or added.
> > 
> > I don't see why you think it was okay to propose this in the way you
> > have gone about it.  Looking at the mailing list, you've been around for
> > a while.
> 
> This should probably have been posted as RFC rather than PATCH, but as I
> indicate in the cover letter this is broken down to allow maintainers like
> yourself to accept/reject
> 
> > 
> > The file you are telling me about seems to be extremely new and I needed
> > to pull akpm/mm-new to discover where it came from.. because you never
> > Cc'ed me on the file you are asking me to own.
> 
> Yes, that file is very new indeed, and my bad for not copying you on it.
> 
> I was not planning on burning an entire day worth of work to transition the
> GDB scripts dumping the interrupt tree away from a radix tree to a maple
> tree. All of which happens with the author of that conversion having
> absolutely no idea that broke anything in the tree because very few people
> know about the Python GDB scripts that Linux has. It is not pleasant to be
> playing catch when it would have take maybe an extra couple hours for
> someone intimately familiar with the maple tree to come up with a suitable
> implementation replacement for mtree_load().
> 
> So having done it felt like there is a maintenance void that needs to be
> filled, hence this patch set.

I can see that it takes a lot of time to do a major update of a gdb
debugging script after some refactoring like this. OTOH mandating some gdb
scripts update is adding non-trivial amount of work to changes that are
already hard enough to do as is. And the obvious question is what is the
value? I've personally never used these gdb scripts and never felt a strong
need for something like that. People have various debugging aids (like BPF
scripts, gdb scripts, there's crash tool and drgn, and many more) lying
around.  I'm personally of an opinion that it is not a responsibility of
the person doing refactoring to make life easier for them or even fixing
them and I don't think that the fact that some debug aid is under
scripts/gdb/ directory is making it more special. So at least as far as I'm
concerned (VFS, fsnotify and other filesystem related stuff) I don't plan
on requiring updates to gdb scripts from people doing changes or otherwise
actively maintain them.

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR