[PATCH v2 4/6] phy: qcom: qmp-usb-legacy: Fix possible NULL-deref on early runtime suspend

[Abel Vesa]

On 26-01-21 15:28:25, Loic Poulain wrote:
> There is a small window where the runtime suspend callback may run
> after pm_runtime_enable() and before pm_runtime_forbid(). In this
> case, a crash occurs because runtime suspend/resume dereferences
> qmp->phy pointer, which is not yet initialized:
>         `if (!qmp->phy->init_count) {`
> 
> This can also happen if user re-enables runtime-pm via the sysfs
> attribute before qmp phy is initialized.
> 
> Similarly to other qcom phy drivers, introduce a qmp->phy_initialized
> variable that can be used to avoid relying on the possibly uninitialized
> phy pointer.
> 
> Fixes: e464a3180a43 ("phy: qcom-qmp-usb: split off the legacy USB+dp_com support")
> Signed-off-by: Loic Poulain <loic.poulain at oss.qualcomm.com>

Reviewed-by: Abel Vesa <abel.vesa at oss.qualcomm.com>