Commit b8f0009b authored by Dave Airlie's avatar Dave Airlie
Browse files

Merge tag 'drm-misc-fixes-2022-06-30' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes 



A NULL pointer dereference fix for vc4, and 3 patches to improve the
sysfb device behaviour when removing conflicting framebuffers

Signed-off-by: default avatarDave Airlie <airlied@redhat.com>

From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220630072404.2fa4z3nk5h5q34ci@houat
parents 078a3be7 ee7a69aa

Documentation/driver-api/firmware/other_interfaces.rst

+6 −0
Original line number Diff line number Diff line
@@ -13,6 +13,12 @@ EDD Interfaces 
.. kernel-doc:: drivers/firmware/edd.c

   :internal:



Generic System Framebuffers Interface

-------------------------------------



.. kernel-doc:: drivers/firmware/sysfb.c

   :export:



Intel Stratix10 SoC Service Layer

---------------------------------

Some features of the Intel Stratix10 SoC require a level of privilege

drivers/firmware/sysfb.c

+50 −8
Original line number Diff line number Diff line
@@ -34,21 +34,59 @@ 
#include <linux/screen_info.h>

#include <linux/sysfb.h>



static struct platform_device *pd;

static DEFINE_MUTEX(disable_lock);

static bool disabled;



static bool sysfb_unregister(void)

{

	if (IS_ERR_OR_NULL(pd))

		return false;



	platform_device_unregister(pd);

	pd = NULL;



	return true;

}



/**

 * sysfb_disable() - disable the Generic System Framebuffers support

 *

 * This disables the registration of system framebuffer devices that match the

 * generic drivers that make use of the system framebuffer set up by firmware.

 *

 * It also unregisters a device if this was already registered by sysfb_init().

 *

 * 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)

{

	mutex_lock(&disable_lock);

	sysfb_unregister();

	disabled = true;

	mutex_unlock(&disable_lock);

}

EXPORT_SYMBOL_GPL(sysfb_disable);



static __init int sysfb_init(void)

{

	struct screen_info *si = &screen_info;

	struct simplefb_platform_data mode;

	struct platform_device *pd;

	const char *name;

	bool compatible;

	int ret;

	int ret = 0;



	mutex_lock(&disable_lock);

	if (disabled)

		goto unlock_mutex;



	/* try to create a simple-framebuffer device */

	compatible = sysfb_parse_mode(si, &mode);

	if (compatible) {

		ret = sysfb_create_simplefb(si, &mode);

		if (!ret)

			return 0;

		pd = sysfb_create_simplefb(si, &mode);

		if (!IS_ERR(pd))

			goto unlock_mutex;

	}



	/* if the FB is incompatible, create a legacy framebuffer device */
@@ -60,8 +98,10 @@ static __init int sysfb_init(void) 
		name = "platform-framebuffer";



	pd = platform_device_alloc(name, 0);

	if (!pd)

		return -ENOMEM;

	if (!pd) {

		ret = -ENOMEM;

		goto unlock_mutex;

	}



	sysfb_apply_efi_quirks(pd);
@@ -73,9 +113,11 @@ static __init int sysfb_init(void) 
	if (ret)

		goto err;



	return 0;

	goto unlock_mutex;

err:

	platform_device_put(pd);

unlock_mutex:

	mutex_unlock(&disable_lock);

	return ret;

}

drivers/firmware/sysfb_simplefb.c

+8 −8
Original line number Diff line number Diff line
@@ -57,7 +57,7 @@ __init bool sysfb_parse_mode(const struct screen_info *si, 
	return false;

}



__init int sysfb_create_simplefb(const struct screen_info *si,

__init struct platform_device *sysfb_create_simplefb(const struct screen_info *si,

						     const struct simplefb_platform_data *mode)

{

	struct platform_device *pd;
@@ -76,7 +76,7 @@ __init int sysfb_create_simplefb(const struct screen_info *si, 
		base |= (u64)si->ext_lfb_base << 32;

	if (!base || (u64)(resource_size_t)base != base) {

		printk(KERN_DEBUG "sysfb: inaccessible VRAM base\n");

		return -EINVAL;

		return ERR_PTR(-EINVAL);

	}



	/*
@@ -93,7 +93,7 @@ __init int sysfb_create_simplefb(const struct screen_info *si, 
	length = mode->height * mode->stride;

	if (length > size) {

		printk(KERN_WARNING "sysfb: VRAM smaller than advertised\n");

		return -EINVAL;

		return ERR_PTR(-EINVAL);

	}

	length = PAGE_ALIGN(length);
@@ -104,11 +104,11 @@ __init int sysfb_create_simplefb(const struct screen_info *si, 
	res.start = base;

	res.end = res.start + length - 1;

	if (res.end <= res.start)

		return -EINVAL;

		return ERR_PTR(-EINVAL);



	pd = platform_device_alloc("simple-framebuffer", 0);

	if (!pd)

		return -ENOMEM;

		return ERR_PTR(-ENOMEM);



	sysfb_apply_efi_quirks(pd);
@@ -124,10 +124,10 @@ __init int sysfb_create_simplefb(const struct screen_info *si, 
	if (ret)

		goto err_put_device;



	return 0;

	return pd;



err_put_device:

	platform_device_put(pd);



	return ret;

	return ERR_PTR(ret);

}

drivers/gpu/drm/vc4/vc4_perfmon.c

+6 −3
Original line number Diff line number Diff line
@@ -17,12 +17,15 @@ 


void vc4_perfmon_get(struct vc4_perfmon *perfmon)

{

	struct vc4_dev *vc4 = perfmon->dev;

	struct vc4_dev *vc4;



	if (!perfmon)

		return;



	vc4 = perfmon->dev;

	if (WARN_ON_ONCE(vc4->is_vc5))

		return;



	if (perfmon)

	refcount_inc(&perfmon->refcnt);

}

drivers/video/fbdev/core/fbmem.c

+12 −0
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 
#include <linux/kernel.h>

#include <linux/major.h>

#include <linux/slab.h>

#include <linux/sysfb.h>

#include <linux/mm.h>

#include <linux/mman.h>

#include <linux/vt.h>
@@ -1752,6 +1753,17 @@ int remove_conflicting_framebuffers(struct apertures_struct *a, 
		do_free = true;

	}



	/*

	 * If a driver asked to unregister a platform device registered by

	 * sysfb, then can be assumed that this is a driver for a display

	 * that is set up by the system firmware and has a generic driver.

	 *

	 * Drivers for devices that don't have a generic driver will never

	 * 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();



	mutex_lock(&registration_lock);

	do_remove_conflicting_framebuffers(a, name, primary);

	mutex_unlock(&registration_lock);