| Message ID | 20240821191135.829765-1-alexander.deucher@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [V3] video/aperture: optionally match the device in sysfb_disable() | expand |
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>
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) > { > } >
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) > { > } >
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) { }
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(-)