Re: [PATCH 6.6 000/684] 6.6.128-rc2 review

[Brett A C Sheffield]

On 2026-03-02 19:35, Brett A C Sheffield wrote:
> # Librecast Test Results (FAIL)
> 
> 020/020 [ OK ] liblcrq
> 010/010 [ OK ] libmld
> 120/120 [ OK ] liblibrecast
> 
> CPU/kernel: Linux auntie 6.6.128-rc2-ge6906aa7f5ea #1 SMP PREEMPT_DYNAMIC Mon Mar  2 17:31:27 -00 2026 x86_64 AMD Ryzen 9 9950X 16-Core Processor AuthenticAMD GNU/Linux
> 
> Builds, boots and passes network tests.  Fails to poweroff.
> 
> Bisects to commit 3ba77c48498f0fa29456e2435d7d49eafc0a279c (upstream 4589712e0111352973131bad975023b25569287c) and affects 6.6.y and 6.12.y. Other kernels are unaffected, including mainline.

Are we dropping the offending commit from 6.6.y and 6.12.y and retesting?

It is 100% reliably hung on every shutdown with (both) RC2s.

> $ git bisect log
> git bisect start
> # status: waiting for both good and bad commits
> # bad: [e6906aa7f5ea74831bc56d675e1173abf4d1d5a8] Linux 6.6.128-rc2
> git bisect bad e6906aa7f5ea74831bc56d675e1173abf4d1d5a8
> # status: waiting for good commit(s), bad commit known
> # good: [7a137e9bfa0e1919555d60f9dc0c05a7a5ba75d0] Linux 6.6.127
> git bisect good 7a137e9bfa0e1919555d60f9dc0c05a7a5ba75d0
> # good: [4f052e01c0df1f3dc9d89125466b3fa8ee4373d6] hfsplus: fix volume corruption issue for generic/498
> git bisect good 4f052e01c0df1f3dc9d89125466b3fa8ee4373d6
> # bad: [2f93eb27e8efeb0002eba89a82778d569a336279] thermal: int340x: Fix sysfs group leak on DLVR registration failure
> git bisect bad 2f93eb27e8efeb0002eba89a82778d569a336279
> # bad: [8a4170ff96cdf6899b63a78bc588e96ecf0d6063] wifi: rtw88: 8822b: Avoid WARNING in rtw8822b_config_trx_mode()
> git bisect bad 8a4170ff96cdf6899b63a78bc588e96ecf0d6063
> # good: [51de6101987dace2f4a6235f5b6bd57dc4487a46] media: dvb-core: dmxdevfilter must always flush bufs
> git bisect good 51de6101987dace2f4a6235f5b6bd57dc4487a46
> # good: [21129c98b9191dcb1590084871266ab228a8daf1] hyper-v: Mark inner union in hv_kvp_exchg_msg_value as packed
> git bisect good 21129c98b9191dcb1590084871266ab228a8daf1
> # bad: [73c2788b3f488c6d559abb2a4acce54fc6108530] ASoC: sunxi: sun50i-dmic: Add missing check for devm_regmap_init_mmio
> git bisect bad 73c2788b3f488c6d559abb2a4acce54fc6108530
> # bad: [059f60a78995ad5f3dea512a1b8d31067f3cce42] drm/atmel-hlcdc: fix use-after-free of drm_crtc_commit after release
> git bisect bad 059f60a78995ad5f3dea512a1b8d31067f3cce42
> # bad: [3ba77c48498f0fa29456e2435d7d49eafc0a279c] drm/amd/display: Ensure link output is disabled in backend reset for PLL_ON
> git bisect bad 3ba77c48498f0fa29456e2435d7d49eafc0a279c
> # good: [a7953ccb0261ccb358d15f9d51cd85eb6e7fdbda] virt: vbox: uapi: Mark inner unions in packed structs as packed
> git bisect good a7953ccb0261ccb358d15f9d51cd85eb6e7fdbda
> # first bad commit: [3ba77c48498f0fa29456e2435d7d49eafc0a279c] drm/amd/display: Ensure link output is disabled in backend reset for PLL_ON
> 
> commit 3ba77c48498f0fa29456e2435d7d49eafc0a279c
> Author: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx>
> Date:   Tue Jan 6 11:11:19 2026 -0500
> 
>     drm/amd/display: Ensure link output is disabled in backend reset for PLL_ON
> 
>     [ Upstream commit 4589712e0111352973131bad975023b25569287c ]
> 
>     [Why]
>     We're missing the code to actually disable the link output when we have
>     to leave the SYMCLK_ON but the TX remains OFF.
> 
>     [How]
>     Port the code from DCN401 that detects SYMCLK_ON_TX_OFF and disable
>     the link output when the backend is reset.
> 
>     Reviewed-by: Ovidiu (Ovi) Bunea <ovidiu.bunea@xxxxxxx>
>     Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx>
>     Signed-off-by: Matthew Stewart <matthew.stewart2@xxxxxxx>
>     Tested-by: Dan Wheeler <daniel.wheeler@xxxxxxx>
>     Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
>     Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> 
>  drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hwseq.c | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)
> 
>