[PATCH V3] video/aperture: optionally match the device in sysfb_disable()

[PATCH V3] video/aperture: optionally match the device in sysfb_disable()

[Alex Deucher]

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
---
 drivers/firmware/sysfb.c | 19 +++++++++++++------
 drivers/of/platform.c    |  2 +-
 drivers/video/aperture.c | 11 +++--------
 include/linux/sysfb.h    |  4 ++--
 4 files changed, 19 insertions(+), 17 deletions(-)

diff --git a/drivers/firmware/sysfb.c b/drivers/firmware/sysfb.c
index 880ffcb50088..ac4680dc463f 100644
--- a/drivers/firmware/sysfb.c
+++ b/drivers/firmware/sysfb.c
@@ -39,6 +39,8 @@ static struct platform_device *pd;
 static DEFINE_MUTEX(disable_lock);
 static bool disabled;
 
+static struct device *sysfb_parent_dev(const struct screen_info *si);
+
 static bool sysfb_unregister(void)
 {
 	if (IS_ERR_OR_NULL(pd))
@@ -52,6 +54,7 @@ static bool sysfb_unregister(void)
 
 /**
  * sysfb_disable() - disable the Generic System Framebuffers support
+ * @dev:	the device to check if non-NULL
  *
  * This disables the registration of system framebuffer devices that match the
  * generic drivers that make use of the system framebuffer set up by firmware.
@@ -61,17 +64,21 @@ static bool sysfb_unregister(void)
  * Context: The function can sleep. A @disable_lock mutex is acquired to serialize
  *          against sysfb_init(), that registers a system framebuffer device.
  */
-void sysfb_disable(void)
+void sysfb_disable(struct device *dev)
 {
+	struct screen_info *si = &screen_info;
+
 	mutex_lock(&disable_lock);
-	sysfb_unregister();
-	disabled = true;
+	if (!dev || dev == sysfb_parent_dev(si)) {
+		sysfb_unregister();
+		disabled = true;
+	}
 	mutex_unlock(&disable_lock);
 }
 EXPORT_SYMBOL_GPL(sysfb_disable);
 
 #if defined(CONFIG_PCI)
-static __init bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
+static bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
 {
 	/*
 	 * TODO: Try to integrate this code into the PCI subsystem
@@ -87,13 +94,13 @@ static __init bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
 	return true;
 }
 #else
-static __init bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
+static bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
 {
 	return false;
 }
 #endif
 
-static __init struct device *sysfb_parent_dev(const struct screen_info *si)
+static struct device *sysfb_parent_dev(const struct screen_info *si)
 {
 	struct pci_dev *pdev;
 
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 389d4ea6bfc1..ef622d41eb5b 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -592,7 +592,7 @@ static int __init of_platform_default_populate_init(void)
 			 * This can happen for example on DT systems that do EFI
 			 * booting and may provide a GOP handle to the EFI stub.
 			 */
-			sysfb_disable();
+			sysfb_disable(NULL);
 			of_platform_device_create(node, NULL, NULL);
 			of_node_put(node);
 		}
diff --git a/drivers/video/aperture.c b/drivers/video/aperture.c
index 561be8feca96..2b5a1e666e9b 100644
--- a/drivers/video/aperture.c
+++ b/drivers/video/aperture.c
@@ -293,7 +293,7 @@ int aperture_remove_conflicting_devices(resource_size_t base, resource_size_t si
 	 * ask for this, so let's assume that a real driver for the display
 	 * was already probed and prevent sysfb to register devices later.
 	 */
-	sysfb_disable();
+	sysfb_disable(NULL);
 
 	aperture_detach_devices(base, size);
 
@@ -346,15 +346,10 @@ EXPORT_SYMBOL(__aperture_remove_legacy_vga_devices);
  */
 int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *name)
 {
-	bool primary = false;
 	resource_size_t base, size;
 	int bar, ret = 0;
 
-	if (pdev == vga_default_device())
-		primary = true;
-
-	if (primary)
-		sysfb_disable();
+	sysfb_disable(&pdev->dev);
 
 	for (bar = 0; bar < PCI_STD_NUM_BARS; ++bar) {
 		if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM))
@@ -370,7 +365,7 @@ int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *na
 	 * that consumes the VGA framebuffer I/O range. Remove this
 	 * device as well.
 	 */
-	if (primary)
+	if (pdev == vga_default_device())
 		ret = __aperture_remove_legacy_vga_devices(pdev);
 
 	return ret;
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)
 {
 }
 
-- 
2.46.0

✗ Fi.CI.BAT: failure for video/aperture: optionally match the device in sysfb_disable()

[Patchwork]

[-- Attachment #1: Type: text/plain, Size: 4084 bytes --]

== Series Details ==

Series: video/aperture: optionally match the device in sysfb_disable()
URL   : https://patchwork.freedesktop.org/series/137585/
State : failure

== Summary ==

CI Bug Log - changes from CI_DRM_15272 -> Patchwork_137585v1
====================================================

Summary
-------

  **FAILURE**

  Serious unknown changes coming with Patchwork_137585v1 absolutely need to be
  verified manually.
  
  If you think the reported changes have nothing to do with the changes
  introduced in Patchwork_137585v1, please notify your bug team (I915-ci-infra@lists.freedesktop.org) to allow them
  to document this new failure mode, which will reduce false positives in CI.

  External URL: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_137585v1/index.html

Participating hosts (40 -> 39)
------------------------------

  Additional (2): fi-glk-j4005 fi-bsw-n3050 
  Missing    (3): bat-dg2-8 fi-snb-2520m fi-kbl-8809g 

Possible new issues
-------------------

  Here are the unknown changes that may have been introduced in Patchwork_137585v1:

### IGT changes ###

#### Possible regressions ####

  * igt@fbdev@read:
    - bat-arls-1:         [PASS][1] -> [DMESG-WARN][2]
   [1]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_15272/bat-arls-1/igt@fbdev@read.html
   [2]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_137585v1/bat-arls-1/igt@fbdev@read.html

  
Known issues
------------

  Here are the changes found in Patchwork_137585v1 that come from known issues:

### IGT changes ###

#### Issues hit ####

  * igt@gem_huc_copy@huc-copy:
    - fi-glk-j4005:       NOTRUN -> [SKIP][3] ([i915#2190])
   [3]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_137585v1/fi-glk-j4005/igt@gem_huc_copy@huc-copy.html

  * igt@gem_lmem_swapping@basic:
    - fi-glk-j4005:       NOTRUN -> [SKIP][4] ([i915#4613]) +3 other tests skip
   [4]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_137585v1/fi-glk-j4005/igt@gem_lmem_swapping@basic.html

  * igt@gem_lmem_swapping@random-engines:
    - fi-bsw-n3050:       NOTRUN -> [SKIP][5] +19 other tests skip
   [5]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_137585v1/fi-bsw-n3050/igt@gem_lmem_swapping@random-engines.html

  * igt@i915_selftest@live@hangcheck:
    - bat-arls-2:         [PASS][6] -> [DMESG-WARN][7] ([i915#11349])
   [6]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_15272/bat-arls-2/igt@i915_selftest@live@hangcheck.html
   [7]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_137585v1/bat-arls-2/igt@i915_selftest@live@hangcheck.html

  * igt@kms_cursor_legacy@basic-busy-flip-before-cursor-atomic:
    - fi-glk-j4005:       NOTRUN -> [SKIP][8] +10 other tests skip
   [8]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_137585v1/fi-glk-j4005/igt@kms_cursor_legacy@basic-busy-flip-before-cursor-atomic.html

  
#### Possible fixes ####

  * igt@i915_selftest@live@uncore:
    - {bat-arlh-3}:       [INCOMPLETE][9] -> [PASS][10]
   [9]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_15272/bat-arlh-3/igt@i915_selftest@live@uncore.html
   [10]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_137585v1/bat-arlh-3/igt@i915_selftest@live@uncore.html

  
  {name}: This element is suppressed. This means it is ignored when computing
          the status of the difference (SUCCESS, WARNING, or FAILURE).

  [i915#11349]: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/11349
  [i915#2190]: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/2190
  [i915#4613]: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/4613


Build changes
-------------

  * Linux: CI_DRM_15272 -> Patchwork_137585v1

  CI-20190529: 20190529
  CI_DRM_15272: ddbda36f876f53498924155abfa1cd4c58517903 @ git://anongit.freedesktop.org/gfx-ci/linux
  IGT_7982: 76ebe4ecfa1757f21e3f1d3be5993088a92cd274 @ https://gitlab.freedesktop.org/drm/igt-gpu-tools.git
  Patchwork_137585v1: ddbda36f876f53498924155abfa1cd4c58517903 @ git://anongit.freedesktop.org/gfx-ci/linux

== Logs ==

For more details see: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_137585v1/index.html

[-- Attachment #2: Type: text/html, Size: 4880 bytes --]

Re: [PATCH V3] video/aperture: optionally match the device in sysfb_disable()

[Javier Martinez Canillas]

Alex Deucher <alexander.deucher@amd.com> writes:

Hello Alex,

> 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
> ---

This version looks good to me. Thanks!

Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>

-- 
Best regards,

Javier Martinez Canillas
Core Platforms
Red Hat

Re: [PATCH V3] video/aperture: optionally match the device in sysfb_disable()

[Thomas Zimmermann]

Am 21.08.24 um 21:11 schrieb Alex Deucher:
> 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

This change also makes aperture_remove_conflicting_pci_devices() much 
cleaner. Thanks a lot. Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
> ---
>   drivers/firmware/sysfb.c | 19 +++++++++++++------
>   drivers/of/platform.c    |  2 +-
>   drivers/video/aperture.c | 11 +++--------
>   include/linux/sysfb.h    |  4 ++--
>   4 files changed, 19 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/firmware/sysfb.c b/drivers/firmware/sysfb.c
> index 880ffcb50088..ac4680dc463f 100644
> --- a/drivers/firmware/sysfb.c
> +++ b/drivers/firmware/sysfb.c
> @@ -39,6 +39,8 @@ static struct platform_device *pd;
>   static DEFINE_MUTEX(disable_lock);
>   static bool disabled;
>   
> +static struct device *sysfb_parent_dev(const struct screen_info *si);
> +
>   static bool sysfb_unregister(void)
>   {
>   	if (IS_ERR_OR_NULL(pd))
> @@ -52,6 +54,7 @@ static bool sysfb_unregister(void)
>   
>   /**
>    * sysfb_disable() - disable the Generic System Framebuffers support
> + * @dev:	the device to check if non-NULL
>    *
>    * This disables the registration of system framebuffer devices that match the
>    * generic drivers that make use of the system framebuffer set up by firmware.
> @@ -61,17 +64,21 @@ static bool sysfb_unregister(void)
>    * Context: The function can sleep. A @disable_lock mutex is acquired to serialize
>    *          against sysfb_init(), that registers a system framebuffer device.
>    */
> -void sysfb_disable(void)
> +void sysfb_disable(struct device *dev)
>   {
> +	struct screen_info *si = &screen_info;
> +
>   	mutex_lock(&disable_lock);
> -	sysfb_unregister();
> -	disabled = true;
> +	if (!dev || dev == sysfb_parent_dev(si)) {
> +		sysfb_unregister();
> +		disabled = true;
> +	}
>   	mutex_unlock(&disable_lock);
>   }
>   EXPORT_SYMBOL_GPL(sysfb_disable);
>   
>   #if defined(CONFIG_PCI)
> -static __init bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
> +static bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
>   {
>   	/*
>   	 * TODO: Try to integrate this code into the PCI subsystem
> @@ -87,13 +94,13 @@ static __init bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
>   	return true;
>   }
>   #else
> -static __init bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
> +static bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
>   {
>   	return false;
>   }
>   #endif
>   
> -static __init struct device *sysfb_parent_dev(const struct screen_info *si)
> +static struct device *sysfb_parent_dev(const struct screen_info *si)
>   {
>   	struct pci_dev *pdev;
>   
> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> index 389d4ea6bfc1..ef622d41eb5b 100644
> --- a/drivers/of/platform.c
> +++ b/drivers/of/platform.c
> @@ -592,7 +592,7 @@ static int __init of_platform_default_populate_init(void)
>   			 * This can happen for example on DT systems that do EFI
>   			 * booting and may provide a GOP handle to the EFI stub.
>   			 */
> -			sysfb_disable();
> +			sysfb_disable(NULL);
>   			of_platform_device_create(node, NULL, NULL);
>   			of_node_put(node);
>   		}
> diff --git a/drivers/video/aperture.c b/drivers/video/aperture.c
> index 561be8feca96..2b5a1e666e9b 100644
> --- a/drivers/video/aperture.c
> +++ b/drivers/video/aperture.c
> @@ -293,7 +293,7 @@ int aperture_remove_conflicting_devices(resource_size_t base, resource_size_t si
>   	 * ask for this, so let's assume that a real driver for the display
>   	 * was already probed and prevent sysfb to register devices later.
>   	 */
> -	sysfb_disable();
> +	sysfb_disable(NULL);
>   
>   	aperture_detach_devices(base, size);
>   
> @@ -346,15 +346,10 @@ EXPORT_SYMBOL(__aperture_remove_legacy_vga_devices);
>    */
>   int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *name)
>   {
> -	bool primary = false;
>   	resource_size_t base, size;
>   	int bar, ret = 0;
>   
> -	if (pdev == vga_default_device())
> -		primary = true;
> -
> -	if (primary)
> -		sysfb_disable();
> +	sysfb_disable(&pdev->dev);
>   
>   	for (bar = 0; bar < PCI_STD_NUM_BARS; ++bar) {
>   		if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM))
> @@ -370,7 +365,7 @@ int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *na
>   	 * that consumes the VGA framebuffer I/O range. Remove this
>   	 * device as well.
>   	 */
> -	if (primary)
> +	if (pdev == vga_default_device())
>   		ret = __aperture_remove_legacy_vga_devices(pdev);
>   
>   	return ret;
> 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)
>   {
>   }
>   

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)

Re: [PATCH V3] video/aperture: optionally match the device in sysfb_disable()

[Thomas Zimmermann]

Am 21.08.24 um 21:11 schrieb Alex Deucher:
> 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: Thomas Zimmermann <tzimmermann@suse.de>

> ---
>   drivers/firmware/sysfb.c | 19 +++++++++++++------
>   drivers/of/platform.c    |  2 +-
>   drivers/video/aperture.c | 11 +++--------
>   include/linux/sysfb.h    |  4 ++--
>   4 files changed, 19 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/firmware/sysfb.c b/drivers/firmware/sysfb.c
> index 880ffcb50088..ac4680dc463f 100644
> --- a/drivers/firmware/sysfb.c
> +++ b/drivers/firmware/sysfb.c
> @@ -39,6 +39,8 @@ static struct platform_device *pd;
>   static DEFINE_MUTEX(disable_lock);
>   static bool disabled;
>   
> +static struct device *sysfb_parent_dev(const struct screen_info *si);
> +
>   static bool sysfb_unregister(void)
>   {
>   	if (IS_ERR_OR_NULL(pd))
> @@ -52,6 +54,7 @@ static bool sysfb_unregister(void)
>   
>   /**
>    * sysfb_disable() - disable the Generic System Framebuffers support
> + * @dev:	the device to check if non-NULL
>    *
>    * This disables the registration of system framebuffer devices that match the
>    * generic drivers that make use of the system framebuffer set up by firmware.
> @@ -61,17 +64,21 @@ static bool sysfb_unregister(void)
>    * Context: The function can sleep. A @disable_lock mutex is acquired to serialize
>    *          against sysfb_init(), that registers a system framebuffer device.
>    */
> -void sysfb_disable(void)
> +void sysfb_disable(struct device *dev)
>   {
> +	struct screen_info *si = &screen_info;
> +
>   	mutex_lock(&disable_lock);
> -	sysfb_unregister();
> -	disabled = true;
> +	if (!dev || dev == sysfb_parent_dev(si)) {
> +		sysfb_unregister();
> +		disabled = true;
> +	}
>   	mutex_unlock(&disable_lock);
>   }
>   EXPORT_SYMBOL_GPL(sysfb_disable);
>   
>   #if defined(CONFIG_PCI)
> -static __init bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
> +static bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
>   {
>   	/*
>   	 * TODO: Try to integrate this code into the PCI subsystem
> @@ -87,13 +94,13 @@ static __init bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
>   	return true;
>   }
>   #else
> -static __init bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
> +static bool sysfb_pci_dev_is_enabled(struct pci_dev *pdev)
>   {
>   	return false;
>   }
>   #endif
>   
> -static __init struct device *sysfb_parent_dev(const struct screen_info *si)
> +static struct device *sysfb_parent_dev(const struct screen_info *si)
>   {
>   	struct pci_dev *pdev;
>   
> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> index 389d4ea6bfc1..ef622d41eb5b 100644
> --- a/drivers/of/platform.c
> +++ b/drivers/of/platform.c
> @@ -592,7 +592,7 @@ static int __init of_platform_default_populate_init(void)
>   			 * This can happen for example on DT systems that do EFI
>   			 * booting and may provide a GOP handle to the EFI stub.
>   			 */
> -			sysfb_disable();
> +			sysfb_disable(NULL);
>   			of_platform_device_create(node, NULL, NULL);
>   			of_node_put(node);
>   		}
> diff --git a/drivers/video/aperture.c b/drivers/video/aperture.c
> index 561be8feca96..2b5a1e666e9b 100644
> --- a/drivers/video/aperture.c
> +++ b/drivers/video/aperture.c
> @@ -293,7 +293,7 @@ int aperture_remove_conflicting_devices(resource_size_t base, resource_size_t si
>   	 * ask for this, so let's assume that a real driver for the display
>   	 * was already probed and prevent sysfb to register devices later.
>   	 */
> -	sysfb_disable();
> +	sysfb_disable(NULL);
>   
>   	aperture_detach_devices(base, size);
>   
> @@ -346,15 +346,10 @@ EXPORT_SYMBOL(__aperture_remove_legacy_vga_devices);
>    */
>   int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *name)
>   {
> -	bool primary = false;
>   	resource_size_t base, size;
>   	int bar, ret = 0;
>   
> -	if (pdev == vga_default_device())
> -		primary = true;
> -
> -	if (primary)
> -		sysfb_disable();
> +	sysfb_disable(&pdev->dev);
>   
>   	for (bar = 0; bar < PCI_STD_NUM_BARS; ++bar) {
>   		if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM))
> @@ -370,7 +365,7 @@ int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *na
>   	 * that consumes the VGA framebuffer I/O range. Remove this
>   	 * device as well.
>   	 */
> -	if (primary)
> +	if (pdev == vga_default_device())
>   		ret = __aperture_remove_legacy_vga_devices(pdev);
>   
>   	return ret;
> 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)
>   {
>   }
>   

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)