mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git
synced 2026-11-01 23:04:54 +01:00
Alex Deucher
b49420d6a1
In aperture_remove_conflicting_pci_devices(), we currently only
call sysfb_disable() on vga class devices. This leads to the
following problem when the pimary device is not VGA compatible:
1. A PCI device with a non-VGA class is the boot display
2. That device is probed first and it is not a VGA device so
sysfb_disable() is not called, but the device resources
are freed by aperture_detach_platform_device()
3. Non-primary GPU has a VGA class and it ends up calling sysfb_disable()
4. NULL pointer dereference via sysfb_disable() since the resources
have already been freed by aperture_detach_platform_device() when
it was called by the other device.
Fix this by passing a device pointer to sysfb_disable() and checking
the device to determine if we should execute it or not.
v2: Fix build when CONFIG_SCREEN_INFO is not set
v3: Move device check into the mutex
Drop primary variable in aperture_remove_conflicting_pci_devices()
Drop __init on pci sysfb_pci_dev_is_enabled()
Fixes: 5ae3716cfd ("video/aperture: Only remove sysfb on the default vga pci device")
Cc: Javier Martinez Canillas <[email protected]>
Cc: Thomas Zimmermann <[email protected]>
Cc: Helge Deller <[email protected]>
Cc: Sam Ravnborg <[email protected]>
Cc: Daniel Vetter <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
Cc: [email protected]
Reviewed-by: Javier Martinez Canillas <[email protected]>
Reviewed-by: Thomas Zimmermann <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]