[PATCH printk v3 0/2] nbcon irq_work fixes

John Ogness posted 2 patches 3 weeks, 4 days ago
kernel/printk/nbcon.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
[PATCH printk v3 0/2] nbcon irq_work fixes
Posted by John Ogness 3 weeks, 4 days ago
Hi,

This is v3 of a series to address some irq_work issues with nbcon.
Initially motivated as a workaround for hardware-related regressions
reported [0], it turns out that the workaround is actually a nice
improvement for nbcon deferred printing in general.

v2 is here [1].

The changes since v2:

- On nbcon_free(), perform the irq_work flush before stopping the
  kthread printer.

- Rework the commit message of patch 2/2 so that reducing interrupts
  is the primary motivation and the Tegra workaround is a secondary
  "benefit". I really want the Tegra workaround information to stay
  in the commit message because it is historically significant.

John Ogness

[0] https://lore.kernel.org/lkml/f3757a75-0ba1-4558-bf57-f19ab7e59a4c@nvidia.com
[1] https://lore.kernel.org/lkml/20260828140218.232439-1-john.ogness@linutronix.de

John Ogness (2):
  printk/nbcon: Flush nbcon_irq_work in nbcon_free()
  printk/nbcon: Change nbcon_irq_work to IRQ_WORK_LAZY

 kernel/printk/nbcon.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)


base-commit: ffe0486b139e45cd9c9ca2584f04a1910fe4f8a6
-- 
2.47.3
Re: [PATCH printk v3 0/2] nbcon irq_work fixes
Posted by Petr Mladek 3 weeks, 3 days ago
On Tue 2026-09-01 11:37:41, John Ogness wrote:
> Hi,
> 
> This is v3 of a series to address some irq_work issues with nbcon.
> Initially motivated as a workaround for hardware-related regressions
> reported [0], it turns out that the workaround is actually a nice
> improvement for nbcon deferred printing in general.
> 
> v2 is here [1].
> 
> The changes since v2:
> 
> - On nbcon_free(), perform the irq_work flush before stopping the
>   kthread printer.
> 
> - Rework the commit message of patch 2/2 so that reducing interrupts
>   is the primary motivation and the Tegra workaround is a secondary
>   "benefit". I really want the Tegra workaround information to stay
>   in the commit message because it is historically significant.
> 
> John Ogness
> 
> [0] https://lore.kernel.org/lkml/f3757a75-0ba1-4558-bf57-f19ab7e59a4c@nvidia.com
> [1] https://lore.kernel.org/lkml/20260828140218.232439-1-john.ogness@linutronix.de
> 
> John Ogness (2):
>   printk/nbcon: Flush nbcon_irq_work in nbcon_free()
>   printk/nbcon: Change nbcon_irq_work to IRQ_WORK_LAZY
> 
>  kernel/printk/nbcon.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)

JFYI, the patchset has been comitted into printk/linux.git,
branch for-7.3-irq-work-fixes.

I am going to give it few days in linux-next. Then I will create
a pull request for 7.3 unless any problems got reported.

Best Regards,
Petr