On Fri 06 Mar 04:12 PST 2020, Linus Walleij wrote:
> In the commit setting up the qcom/msm pin controller to
> be hierarchical some callbacks were careful to check that
> d->parent_data on irq_data was valid before calling the
> parent function, however irq_chip_eoi_parent() was called
> unconditionally which doesn't work with elder Qualcomm
> platforms such as APQ8060.
>
> When the drivers/mfd/qcom-pm8xxx.c driver calls
> chained_irq_exit() that call will in turn call chip->irq_eoi()
> which is set to irq_chip_eoi_parent() by default on a
> hierachical IRQ chip, and the parent is pinctrl-msm.c
> so that will in turn unconditionally call
> irq_chip_eoi_parent() again, but its parent is invalid
> so we get the following crash:
>
> Unnable to handle kernel NULL pointer dereference at
> virtual address 00000010
> pgd = (ptrval)
> [00000010] *pgd=00000000
> Internal error: Oops: 5 [#1] PREEMPT SMP ARM
> (...)
> PC is at irq_chip_eoi_parent+0x4/0x10
> LR is at pm8xxx_irq_handler+0x1b4/0x2d8
>
> Implement a local stub just avoiding to call down to
> irq_chip_eoi_parent() if d->parent_data is not set.
>
> Cc: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> Cc: Lina Iyer <ilina@xxxxxxxxxxxxxx>
> Cc: Marc Zyngier <maz@xxxxxxxxxx>
> Cc: Stephen Boyd <swboyd@xxxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: e35a6ae0eb3a ("pinctrl/msm: Setup GPIO chip in hierarchy")
> Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
> ---
> drivers/pinctrl/qcom/pinctrl-msm.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
> index 9a8daa256a32..511f596cf2c3 100644
> --- a/drivers/pinctrl/qcom/pinctrl-msm.c
> +++ b/drivers/pinctrl/qcom/pinctrl-msm.c
> @@ -828,6 +828,12 @@ static void msm_gpio_irq_unmask(struct irq_data *d)
> msm_gpio_irq_clear_unmask(d, false);
> }
>
> +static void msm_gpio_irq_eoi(struct irq_data *d)
I find it odd that the pinctrl-msm driver would be the only place that
needs this. But let's start with this.
Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Regards,
Bjorn
> +{
> + if (d->parent_data)
> + irq_chip_eoi_parent(d);
> +}
> +
> static void msm_gpio_irq_ack(struct irq_data *d)
> {
> struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
> @@ -1104,7 +1110,7 @@ static int msm_gpio_init(struct msm_pinctrl *pctrl)
> pctrl->irq_chip.irq_mask = msm_gpio_irq_mask;
> pctrl->irq_chip.irq_unmask = msm_gpio_irq_unmask;
> pctrl->irq_chip.irq_ack = msm_gpio_irq_ack;
> - pctrl->irq_chip.irq_eoi = irq_chip_eoi_parent;
> + pctrl->irq_chip.irq_eoi = msm_gpio_irq_eoi;
> pctrl->irq_chip.irq_set_type = msm_gpio_irq_set_type;
> pctrl->irq_chip.irq_set_wake = msm_gpio_irq_set_wake;
> pctrl->irq_chip.irq_request_resources = msm_gpio_irq_reqres;
> --
> 2.24.1
>
