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The hierarchical parts of MSM pinctrl/GPIO is only
used when the device tree has a "wakeup-parent" as
a phandle, but the .irq_eoi is anyway assigned leading
to semantic problems on elder Qualcomm chipsets.
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
If we solve this crash by avoiding to call up to
irq_chip_eoi_parent(), the machine will hang and get
reset by the watchdog, because of semantic issues,
probably inside irq_chip.
As a solution, just assign the .irq_eoi conditionally if
we are actually using a wakeup parent.
Cc: David Heidelberg <david@ixit.cz>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Lina Iyer <ilina@codeaurora.org>
Cc: Stephen Boyd <swboyd@chromium.org>
Cc: stable@vger.kernel.org
Fixes:
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|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.