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

Andi Shyti andi.shyti at kernel.org
Wed Dec 6 04:27:38 PST 2023


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 at friendlyarm.com>

Looks good,

Reviewed-by: Andi Shyti <andi.shyti at kernel.org>

Thanks,
Andi



More information about the linux-arm-kernel mailing list