Re: serial 00:06: Runtime PM usage count underflow!

[Borislav Petkov]

On Mon, Nov 18, 2024 at 04:14:20PM +0200, Ilpo Järvinen wrote:
> I think "Runtime PM usage count underflow!" is not related to the probe 
> problem you're seeing. Nonetheless, this patch might solve the underflow:
> 
> --
> [PATCH 1/1] tty: serial: 8250: Fix another runtime PM usage counter underflow
> 
> The commit f9b11229b79c ("serial: 8250: Fix PM usage_count for console
> handover") fixed one runtime PM usage counter balance problem that
> occurs because .dev is not set during univ8250 setup preventing call to
> pm_runtime_get_sync(). Later, univ8250_console_exit() will trigger the
> runtime PM usage counter underflow as .dev is already set at that time.
> 
> Call pm_runtime_get_sync() to balance the RPM usage counter also in
> serial8250_register_8250_port() before trying to add the port.
> 
> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>

Reported-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Tested-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>

Thx!

-- 
Regards/Gruss,
    Boris.

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