Re: [PATCH v3 3/9] serial: qcom-geni: fix shutdown race

[Doug Anderson]

Hi,

On Wed, Oct 9, 2024 at 7:51 AM Johan Hovold <johan+linaro@xxxxxxxxxx> wrote:
>
> A commit adding back the stopping of tx on port shutdown failed to add
> back the locking which had also been removed by commit e83766334f96
> ("tty: serial: qcom_geni_serial: No need to stop tx/rx on UART
> shutdown").
>
> Holding the port lock is needed to serialise against the console code,
> which may update the interrupt enable register and access the port
> state.
>
> Fixes: d8aca2f96813 ("tty: serial: qcom-geni-serial: stop operations in progress at shutdown")
> Fixes: 947cc4ecc06c ("serial: qcom-geni: fix soft lockup on sw flow control and suspend")
> Cc: stable@xxxxxxxxxxxxxxx      # 6.3
> Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
> Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
> ---
>  drivers/tty/serial/qcom_geni_serial.c | 2 ++
>  1 file changed, 2 insertions(+)

Though this doesn't fix the preexisting bug I talked about [1] that
we'll need to touch the same code to fix:

Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>

[1] https://lore.kernel.org/r/CAD=FV=UZtZ1-0SkN2sOMp6YdU02em_RnK85Heg5z0jkH4U30eQ@xxxxxxxxxxxxxx