Hello Aaron,
Hope you are doing well. I am Chaitanya from the linux graphics team in
Intel.
This mail is regarding a regression we are seeing in our CI runs[1] on
linux-next repository.
Since the version next-20251201 [2], we are seeing the following regression
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Starting subtest: load
(i915_module_load:1280) igt_debugfs-CRITICAL: Test assertion failure
function igt_debugfs_path, file ../lib/igt_debugfs.c:121:
(i915_module_load:1280) igt_debugfs-CRITICAL: Failed assertion: debugfs_root
(i915_module_load:1280) igt_debugfs-CRITICAL: Last errno: 2, No such
file or directory
Subtest load failed.
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I see some other drivers also failing to create their debugfs entries.
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[ 0.134437] pinctrl core: failed to create debugfs directory
[ 3.488263] intel-lpss 0000:00:15.0: Failed to create debugfs entries
[ 3.563494] intel-lpss 0000:00:15.1: Failed to create debugfs entries
[ 3.631076] intel-lpss 0000:00:15.2: Failed to create debugfs entries
[ 3.697366] intel-lpss 0000:00:15.3: Failed to create debugfs entries
[ 3.764351] intel-lpss 0000:00:19.0: Failed to create debugfs entries
[ 3.841824] intel-lpss 0000:00:19.1: Failed to create debugfs entries
[ 3.909492] nvme0: failed to create debugfs directory
[ 3.937845] nvme0n1: failed to create debugfs directory
[ 5.636042] pinctrl core: failed to create debugfs directory for
INTC105E:00
[ 177.973628] cec: Failed to create debugfs cec dir
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Detailed log can be found in [3].
After bisecting the tree, the following patch [4] seems to be the first
"bad" commit
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commit f278809475f6835b56de78b28dc2cc0c7e2c20a4
Author: Aaron Thompson [email protected]
Date: Thu Nov 20 10:26:33 2025 +0000
debugfs: Remove broken no-mount mode
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We also verified that if we revert the patch the issue is not seen.
Could you please check why the patch causes this regression and provide
a fix if necessary?
Thank you.
Regards
Chaitanya
[1]
https://intel-gfx-ci.01.org/tree/linux-next/combined-alt.html?
[2]
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?h=next-20251201
[3]
https://intel-gfx-ci.01.org/tree/linux-next/next-20251201/bat-arlh-2/igt@[email protected]
[4]
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?h=next-20251201&id=f278809475f6835b56de78b28dc2cc0c7e2c20a4
