diff options
author | Alex Deucher <alexander.deucher@amd.com> | 2024-08-21 15:11:35 -0400 |
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committer | Alex Deucher <alexander.deucher@amd.com> | 2024-08-26 19:14:48 -0400 |
commit | b49420d6a1aeb399e5b107fc6eb8584d0860fbd7 (patch) | |
tree | c45110f777e404b696244ece8f453bfa84dd3408 /include | |
parent | e9fd436bb8fb9b9d31fdf07bbcdba6d30290c5e4 (diff) | |
download | lwn-b49420d6a1aeb399e5b107fc6eb8584d0860fbd7.tar.gz lwn-b49420d6a1aeb399e5b107fc6eb8584d0860fbd7.zip |
video/aperture: optionally match the device in sysfb_disable()
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: 5ae3716cfdcd ("video/aperture: Only remove sysfb on the default vga pci device")
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Helge Deller <deller@gmx.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240821191135.829765-1-alexander.deucher@amd.com
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/sysfb.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/sysfb.h b/include/linux/sysfb.h index c9cb657dad08..bef5f06a91de 100644 --- a/include/linux/sysfb.h +++ b/include/linux/sysfb.h @@ -58,11 +58,11 @@ struct efifb_dmi_info { #ifdef CONFIG_SYSFB -void sysfb_disable(void); +void sysfb_disable(struct device *dev); #else /* CONFIG_SYSFB */ -static inline void sysfb_disable(void) +static inline void sysfb_disable(struct device *dev) { } |