On Thu, Dec 7, 2023 at 4:37 PM Dragan Simic <dsimic@xxxxxxxxxxx> wrote:
On 2023-12-07 09:21, Jensen Huang wrote:
> Possible deadlock scenario (on reboot):
> rk3x_i2c_xfer_common(polling)
> -> rk3x_i2c_wait_xfer_poll()
> -> rk3x_i2c_irq(0, i2c);
> --> spin_lock(&i2c->lock);
> ...
> <rk3x i2c interrupt>
> -> rk3x_i2c_irq(0, i2c);
> --> spin_lock(&i2c->lock); (deadlock here)
>
> Store the IRQ number and disable/enable it around the polling transfer.
> This patch has been tested on NanoPC-T4.
In case you haven't already seen the related discussion linked below,
please have a look. I also added more people to the list of recipients,
in an attempt to make everyone aware of the different approaches to
solving this issue.
https://lore.kernel.org/all/655177f4.050a0220.d85c9.3ba0@xxxxxxxxxxxxx/T/#m6fc9c214452fec6681843e7f455978c35c6f6c8b
Thank you for providing the information. I hadn't seen this link before.
After carefully looking into the related discussion, it appears that
Dmitry Osipenko is already working on a suitable patch. To avoid duplication
or conflicts, my patch can be discarded.