Quoting Linus Walleij (2020-03-06 04:12:21)
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@linaro.org Cc: Lina Iyer ilina@codeaurora.org Cc: Marc Zyngier maz@kernel.org Cc: Stephen Boyd swboyd@chromium.org Cc: stable@vger.kernel.org Fixes: e35a6ae0eb3a ("pinctrl/msm: Setup GPIO chip in hierarchy") Signed-off-by: Linus Walleij linus.walleij@linaro.org
Reviewed-by: Stephen Boyd swboyd@chromium.org