Re: [PATCH printk v2 0/2] Fix reported suspend failures

[Thierry Reding]

On Thu, Nov 13, 2025 at 05:09:46PM +0106, John Ogness wrote:
> This is v2 of a series to address multiple reports [0][1]
> (+ 2 offlist) of suspend failing when NBCON console drivers are
> in use. With the help of NXP and NVIDIA we were able to isolate
> the problem and verify the fix.
> 
> v1 is here [2].
> 
> The first NBCON drivers appeared in 6.13, so currently there is
> no LTS kernel that requires this series. But it should go into
> 6.17.x and 6.18.
> 
> The changes since v1:
> 
> - For printk_trigger_flush() add support for all flush types
>   that are available. This will prevent printk_trigger_flush()
>   from trying to inappropriately queue irq_work after this
>   series is applied.
> 
> - Add WARN_ON_ONCE() to the printk irq_work queueing functions
>   in case they are called when irq_work is blocked. There
>   should never be (and currently are no) such callers, but
>   these functions are externally available.
> 
> John Ogness
> 
> [0] https://lore.kernel.org/lkml/80b020fc-c18a-4da4-b222-16da1cab2f4c@xxxxxxxxxx
> [1] https://lore.kernel.org/lkml/DB9PR04MB8429E7DDF2D93C2695DE401D92C4A@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> [2] https://lore.kernel.org/lkml/20251111144328.887159-1-john.ogness@xxxxxxxxxxxxx
> 
> John Ogness (2):
>   printk: Allow printk_trigger_flush() to flush all types
>   printk: Avoid scheduling irq_work on suspend
> 
>  kernel/printk/internal.h |  8 ++--
>  kernel/printk/nbcon.c    |  9 ++++-
>  kernel/printk/printk.c   | 81 ++++++++++++++++++++++++++++++++--------
>  3 files changed, 78 insertions(+), 20 deletions(-)

Sorry, I'm a bit late, but this seems to solve all the issues we were
seeing on Tegra boards, so for the record:

Tested-by: Thierry Reding <treding@xxxxxxxxxx>

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