Hello Rafael,
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-20241106 [2], we are seeing the following regression
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<4>[ 7.246473] WARNING: possible circular locking dependency detected
<4>[ 7.246476] 6.12.0-rc6-next-20241106-next-20241106-g5b913f5d7d7f+ #1 Not tainted
<4>[ 7.246479] ------------------------------------------------------
<4>[ 7.246481] swapper/0/1 is trying to acquire lock:
<4>[ 7.246483] ffffffff8264aef0 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_enable+0xd/0x20
<4>[ 7.246493]
but task is already holding lock:
<4>[ 7.246495] ffffffff82832068 (hybrid_capacity_lock){+.+.}-{4:4}, at: intel_pstate_register_driver+0xd3/0x1c0
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Details 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 92447aa5f6e7fbad9427a3fd1bb9e0679c403206
Author: Rafael J. Wysocki mailto:rafael.j.wysocki@xxxxxxxxx
Date: Mon Nov 4 19:53:53 2024 +0100
cpufreq: intel_pstate: Update asym capacity for CPUs that were offline initially
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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-20241106
[3] https://intel-gfx-ci.01.org/tree/linux-next/next-20241106/bat-arls-1/boot0.txt
[4] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?h=next-20241106&id=92447aa5f6e7fbad9427a3fd1bb9e0679c403206
