Re: [PATCH v13 0/9] ref_tracker: add ability to register a debugfs file for a ref_tracker_dir

On Tue, 03 Jun 2025 07:27:11 -0400 Jeff Layton wrote:

For those just joining in, this series adds a new top-level
"ref_tracker" debugfs directory, and has each ref_tracker_dir register a
file in there as part of its initialization. It also adds the ability to
register a symlink with a more human-usable name that points to the
file, and does some general cleanup of how the ref_tracker object names
are handled.

This reposting is mostly to address Krzysztof's comments. I've dropped
the i915 patch, and rebased the rest of the series on top.

Note that I still see debugfs: warnings in the i915 driver even when we
gate the registration of the debugfs file on the classname pointer being
NULL. Here is a CI report from v12:

    https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_148490v8/bat-arls-6/igt@i915_selftest@live@workarounds.html

I think the i915 driver is doing something it shouldn't with these
objects. They seem to be initialized more than once, which could lead
to leaked ref_tracker objects. It would be good for one of the i915
maintainers to comment on whether this is a real problem.

I still see the fs crashes:
https://netdev-3.bots.linux.dev/vmksft-packetdrill-dbg/results/149560/2-tcp-slow-start-slow-start-app-limited-pkt/stderr
I'll hide this series from patchwork for now. We will pull from Linus
on Thu, I'll reactivate it and let's see if the problem was already
fixed.