Re: [PATCH] i2c: rk3x: fix potential spinlock recursion on poll

From: Andi Shyti
Date: Wed Dec 06 2023 - 07:27:56 EST


Hi Jensen,

On Wed, Dec 06, 2023 at 05:06:40PM +0800, 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.
>
> Signed-off-by: Jensen Huang <jensenhuang@xxxxxxxxxxxxxxx>

Looks good,

Reviewed-by: Andi Shyti <andi.shyti@xxxxxxxxxx>

Thanks,
Andi