0d82c163e9
commit 172c48caed91a978bca078042222d09baea13717 upstream.
The acpi_video code was storing the acpi_video_device as driver_data
in the acpi_device children of the acpi_video_bus acpi_device.
But the acpi_video driver only binds to the bus acpi_device.
It uses, but does not bind to, the children. Since it is not
the driver it should not be using the driver_data of the children's
acpi_device-s.
Since commit 0d16710146a1 ("ACPI: bus: Set driver_data to NULL every
time .add() fails") the childen's driver_data ends up getting set
to NULL after a driver fails to bind to the children leading to a NULL
pointer deref in video_get_max_state when registering the cooling-dev:
[ 3.148958] BUG: kernel NULL pointer dereference, address: 0000000000000090
<snip>
[ 3.149015] Hardware name: Sony Corporation VPCSB2X9R/VAIO, BIOS R2087H4 06/15/2012
[ 3.149021] RIP: 0010:video_get_max_state+0x17/0x30 [video]
<snip>
[ 3.149105] Call Trace:
[ 3.149110] <TASK>
[ 3.149114] ? __die+0x23/0x70
[ 3.149126] ? page_fault_oops+0x171/0x4e0
[ 3.149137] ? exc_page_fault+0x7f/0x180
[ 3.149147] ? asm_exc_page_fault+0x26/0x30
[ 3.149158] ? video_get_max_state+0x17/0x30 [video 9b6f3f0d19d7b4a0e2df17a2d8b43bc19c2ed71f]
[ 3.149176] ? __pfx_video_get_max_state+0x10/0x10 [video 9b6f3f0d19d7b4a0e2df17a2d8b43bc19c2ed71f]
[ 3.149192] __thermal_cooling_device_register.part.0+0xf2/0x2f0
[ 3.149205] acpi_video_bus_register_backlight.part.0.isra.0+0x414/0x570 [video 9b6f3f0d19d7b4a0e2df17a2d8b43bc19c2ed71f]
[ 3.149227] acpi_video_register_backlight+0x57/0x80 [video 9b6f3f0d19d7b4a0e2df17a2d8b43bc19c2ed71f]
[ 3.149245] intel_acpi_video_register+0x68/0x90 [i915 1f3a758130b32ef13d301d4f8f78c7d766d57f2a]
[ 3.149669] intel_display_driver_register+0x28/0x50 [i915 1f3a758130b32ef13d301d4f8f78c7d766d57f2a]
[ 3.150064] i915_driver_probe+0x790/0xb90 [i915 1f3a758130b32ef13d301d4f8f78c7d766d57f2a]
[ 3.150402] local_pci_probe+0x45/0xa0
[ 3.150412] pci_device_probe+0xc1/0x260
<snip>
Fix this by directly using the acpi_video_device as devdata for
the cooling-device, which avoids the need to set driver-data on
the children at all.
Fixes: 0d16710146a1 ("ACPI: bus: Set driver_data to NULL every time .add() fails")
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9718
Cc: 6.6+ <stable@vger.kernel.org> # 6.6+
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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There are various text files in the Documentation/ subdirectory,
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Please read the Documentation/process/changes.rst file, as it contains the
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