drm: Expand max DRM device number to full MINORBITS

Having a limit of 64 DRM devices is not good enough for modern world
where we have multi-GPU servers, SR-IOV virtual functions and virtual
devices

drm: Expand max DRM device number to full MINORBITS

Having a limit of 64 DRM devices is not good enough for modern world
where we have multi-GPU servers, SR-IOV virtual functions and virtual
devices used for testing.
Let's utilize full minor range for DRM devices.
To avoid regressing the existing userspace, we're still maintaining the
numbering scheme where 0-63 is used for primary, 64-127 is reserved
(formerly for control) and 128-191 is used for render.
For minors >= 192, we're allocating minors dynamically on a first-come,
first-served basis.

Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240823163048.2676257-4-michal.winiarski@intel.com
Acked-by: James Zhu <James.Zhu@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>

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accel: Use XArray instead of IDR for minors

Accel minor management is based on DRM (and is also using struct
drm_minor internally), since DRM is using XArray for minors, it makes
sense to also conve

accel: Use XArray instead of IDR for minors

Accel minor management is based on DRM (and is also using struct
drm_minor internally), since DRM is using XArray for minors, it makes
sense to also convert accel.
As the two implementations are identical (only difference being the
underlying xarray), move the accel_minor_* functionality to DRM.

Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Acked-by: James Zhu <James.Zhu@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240823163048.2676257-3-michal.winiarski@intel.com
Signed-off-by: Christian König <christian.koenig@amd.com>

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drm: Use XArray instead of IDR for minors

IDR is deprecated, and since XArray manages its own state with internal
locking, it simplifies the locking on DRM side.
Additionally, don't use the IRQ-safe

drm: Use XArray instead of IDR for minors

IDR is deprecated, and since XArray manages its own state with internal
locking, it simplifies the locking on DRM side.
Additionally, don't use the IRQ-safe variant, since operating on drm
minor is not done in IRQ context.

Suggested-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Acked-by: James Zhu <James.Zhu@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240823163048.2676257-2-michal.winiarski@intel.com
Signed-off-by: Christian König <christian.koenig@amd.com>

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drm/panic: Add a QR code panic screen

This patch adds a new panic screen, with a QR code and the kmsg data
embedded.
If DRM_PANIC_SCREEN_QR_CODE_URL is set, then the kmsg data will be
compressed wit

drm/panic: Add a QR code panic screen

This patch adds a new panic screen, with a QR code and the kmsg data
embedded.
If DRM_PANIC_SCREEN_QR_CODE_URL is set, then the kmsg data will be
compressed with zlib and encoded as a numerical segment, and appended
to the URL as a URL parameter. This allows to save space, and put
about ~7500 bytes of kmsg data, in a V40 QR code.
Linux distributions can customize the URL, and put a web frontend to
directly open a bug report with the kmsg data.

Otherwise the kmsg data will be encoded as a binary segment (ie raw
ascii) and only a maximum of 2953 bytes of kmsg data will be
available in the QR code.

You can also limit the QR code size with DRM_PANIC_SCREEN_QR_VERSION.

Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240822073852.562286-5-jfalempe@redhat.com

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drm: deprecate driver date

The driver date serves no useful purpose, because it's hardly ever
updated. The information is misleading at best.

As described in Documentation/gpu/drm-internals.rst:

drm: deprecate driver date

The driver date serves no useful purpose, because it's hardly ever
updated. The information is misleading at best.

As described in Documentation/gpu/drm-internals.rst:

The driver date, formatted as YYYYMMDD, is meant to identify the date
of the latest modification to the driver. However, as most drivers
fail to update it, its value is mostly useless. The DRM core prints it
to the kernel log at initialization time and passes it to userspace
through the DRM_IOCTL_VERSION ioctl.

Stop printing the driver date at init, and start returning the empty
string "" as driver date through the DRM_IOCTL_VERSION ioctl.

The driver date initialization in drivers and the struct drm_driver date
member can be removed in follow-up.

Reviewed-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Acked-by: Simon Ser <contact@emersion.fr>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240429164336.1406480-1-jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

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drm/fbdev: Clean up fbdev documentation

Rewrite some docs that are not up-to-date any longer. Remove the TODO
item for fbdev-generic conversion, as the helper has been replaced. Make
documentation f

drm/fbdev: Clean up fbdev documentation

Rewrite some docs that are not up-to-date any longer. Remove the TODO
item for fbdev-generic conversion, as the helper has been replaced. Make
documentation for DMA, SHMEM and TTM emulation available.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240419083331.7761-44-tzimmermann@suse.de

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drm/panic: Add a drm panic handler

This module displays a user friendly message when a kernel panic
occurs. It currently doesn't contain any debug information,
but that can be added later.

v2
* Us

drm/panic: Add a drm panic handler

This module displays a user friendly message when a kernel panic
occurs. It currently doesn't contain any debug information,
but that can be added later.

v2
* Use get_scanout_buffer() instead of the drm client API.
(Thomas Zimmermann)
* Add the panic reason to the panic message (Nerdopolis)
* Add an exclamation mark (Nerdopolis)

v3
* Rework the drawing functions, to write the pixels line by line and
to use the drm conversion helper to support other formats.
(Thomas Zimmermann)

v4
* Use drm_fb_r1_to_32bit for fonts (Thomas Zimmermann)
* Remove the default y to DRM_PANIC config option (Thomas Zimmermann)
* Add foreground/background color config option
* Fix the bottom lines not painted if the framebuffer height
is not a multiple of the font height.
* Automatically register the device to drm_panic, if the function
get_scanout_buffer exists. (Thomas Zimmermann)

v5
* Change the drawing API, use drm_fb_blit_from_r1() to draw the font.
* Also add drm_fb_fill() to fill area with background color.
* Add draw_pixel_xy() API for drivers that can't provide a linear buffer.
* Add a flush() callback for drivers that needs to synchronize the buffer.
* Add a void *private field, so drivers can pass private data to
draw_pixel_xy() and flush().

v6
* Fix sparse warning for panic_msg and logo.

v7
* Add select DRM_KMS_HELPER for the color conversion functions.

v8
* Register directly each plane to the panic notifier (Sima)
* Add raw_spinlock to properly handle concurrency (Sima)
* Register plane instead of device, to avoid looping through plane
list, and simplify code.
* Replace get_scanout_buffer() logic with drm_panic_set_buffer()
(Thomas Zimmermann)
* Removed the draw_pixel_xy() API, will see later if it can be added back.

v9
* Revert to using get_scanout_buffer() (Sima)
* Move get_scanout_buffer() and panic_flush() to the plane helper
functions (Thomas Zimmermann)
* Register all planes with get_scanout_buffer() to the panic notifier
* Use drm_panic_lock() to protect against race (Sima)

v10
* Move blit and fill functions back in drm_panic (Thomas Zimmermann).
* Simplify the text drawing functions.
* Use kmsg_dumper instead of panic_notifier (Sima).

v12
* Use array for map and pitch in struct drm_scanout_buffer
to support multi-planar format later. (Thomas Zimmermann)
* Better indent struct drm_scanout_buffer declaration. (Thomas Zimmermann)

Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240409163432.352518-3-jfalempe@redhat.com
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>

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drm/panic: Add drm panic locking

Rough sketch for the locking of drm panic printing code. The upshot of
this approach is that we can pretty much entirely rely on the atomic
commit flow, with the pai

drm/panic: Add drm panic locking

Rough sketch for the locking of drm panic printing code. The upshot of
this approach is that we can pretty much entirely rely on the atomic
commit flow, with the pair of raw_spin_lock/unlock providing any
barriers we need, without having to create really big critical
sections in code.

This also avoids the need that drivers must explicitly update the
panic handler state, which they might forget to do, or not do
consistently, and then we blow up in the worst possible times.

It is somewhat racy against a concurrent atomic update, and we might
write into a buffer which the hardware will never display. But there's
fundamentally no way to avoid that - if we do the panic state update
explicitly after writing to the hardware, we might instead write to an
old buffer that the user will barely ever see.

Note that an rcu protected deference of plane->state would give us the
the same guarantees, but it has the downside that we then need to
protect the plane state freeing functions with call_rcu too. Which
would very widely impact a lot of code and therefore doesn't seem
worth the complexity compared to a raw spinlock with very tiny
critical sections. Plus rcu cannot be used to protect access to
peek/poke registers anyway, so we'd still need it for those cases.

Peek/poke registers for vram access (or a gart pte reserved just for
panic code) are also the reason I've gone with a per-device and not
per-plane spinlock, since usually these things are global for the
entire display. Going with per-plane locks would mean drivers for such
hardware would need additional locks, which we don't want, since it
deviates from the per-console takeoverlocks design.

Longer term it might be useful if the panic notifiers grow a bit more
structure than just the absolute bare
EXPORT_SYMBOL(panic_notifier_list) - somewhat aside, why is that not
EXPORT_SYMBOL_GPL ... If panic notifiers would be more like console
drivers with proper register/unregister interfaces we could perhaps
reuse the very fancy console lock with all it's check and takeover
semantics that John Ogness is developing to fix the console_lock mess.
But for the initial cut of a drm panic printing support I don't think
we need that, because the critical sections are extremely small and
only happen once per display refresh. So generally just 60 tiny locked
sections per second, which is nothing compared to a serial console
running a 115kbaud doing really slow mmio writes for each byte. So for
now the raw spintrylock in drm panic notifier callback should be good
enough.

Another benefit of making panic notifiers more like full blown
consoles (that are used in panics only) would be that we get the two
stage design, where first all the safe outputs are used. And then the
dangerous takeover tricks are deployed (where for display drivers we
also might try to intercept any in-flight display buffer flips, which
if we race and misprogram fifos and watermarks can hang the memory
controller on some hw).

For context the actual implementation on the drm side is by Jocelyn
and this patch is meant to be combined with the overall approach in
v7 (v8 is a bit less flexible, which I think is the wrong direction):

https://lore.kernel.org/dri-devel/20240104160301.185915-1-jfalempe@redhat.com/

Note that the locking is very much not correct there, hence this
separate rfc.

Starting from v10, I (Jocelyn) have included this patch in the drm_panic
series, and done the corresponding changes.

v2:
- fix authorship, this was all my typing
- some typo oopsies
- link to the drm panic work by Jocelyn for context

v10:
- Use spinlock_irqsave/restore (John Ogness)

v11:
- Use macro instead of inline functions for drm_panic_lock/unlock (John Ogness)

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jocelyn Falempe <jfalempe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240409163432.352518-2-jfalempe@redhat.com
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>

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drm: Remove support for legacy drivers

Remove all hooks and calls into code for user-space mode setting from
the DRM core. Without the drivers and ioctl entry points, none of this
is required any lo

drm: Remove support for legacy drivers

Remove all hooks and calls into code for user-space mode setting from
the DRM core. Without the drivers and ioctl entry points, none of this
is required any longer.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: David Airlie <airlied@gmail.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231122122449.11588-11-tzimmermann@suse.de

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drm/drv: propagate errors from drm_modeset_register_all()

In case the drm_modeset_register_all() function fails, its error code
will be ignored. Instead make the drm_dev_register() bail out in case

drm/drv: propagate errors from drm_modeset_register_all()

In case the drm_modeset_register_all() function fails, its error code
will be ignored. Instead make the drm_dev_register() bail out in case of
such an error.

Fixes: 79190ea2658a ("drm: Add callbacks for late registering")
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231202225552.1283638-1-dmitry.baryshkov@linaro.org

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drm/debugfs: rework drm_debugfs_create_files implementation v2

Use managed memory allocation for this. That allows us to not keep
track of all the files any more.

v2: keep drm_debugfs_cleanup(), bu

drm/debugfs: rework drm_debugfs_create_files implementation v2

Use managed memory allocation for this. That allows us to not keep
track of all the files any more.

v2: keep drm_debugfs_cleanup(), but rename to drm_debugfs_unregister(),
we still need to cleanup the symlink

Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230829110115.3442-6-christian.koenig@amd.com
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>

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drm/debugfs: remove dev->debugfs_list and debugfs_mutex v2

The mutex was completely pointless in the first place since any
parallel adding of files to this list would result in random
behavior since

drm/debugfs: remove dev->debugfs_list and debugfs_mutex v2

The mutex was completely pointless in the first place since any
parallel adding of files to this list would result in random
behavior since the list is filled and consumed multiple times.

Completely drop that approach and just create the files directly but
return -ENODEV while opening the file when the minors are not
registered yet.

v2: rebase on debugfs directory rework, limit access before minors are
registered.

Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230829110115.3442-5-christian.koenig@amd.com
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>

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drm/debugfs: rework debugfs directory creation v5

Instead of the per minor directories only create a single debugfs
directory for the whole device directly when the device is initialized.

For DRM d

drm/debugfs: rework debugfs directory creation v5

Instead of the per minor directories only create a single debugfs
directory for the whole device directly when the device is initialized.

For DRM devices each minor gets a symlink to the per device directory
for now until we can be sure that this isn't useful any more in any way.

Accel devices create only the per device directory and also drops the mid
layer callback to create driver specific files.

v2: cleanup accel component as well
v3: fix typo when debugfs is disabled
v4: call drm_debugfs_dev_fini() during release as well,
some kerneldoc typos fixed
v5: rebased and one more kerneldoc fix

Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230829110115.3442-4-christian.koenig@amd.com
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>

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drm/drv: use enum drm_minor_type when appropriate

This makes it easier to figure out what the "type" variable can be
set to when reading the implementation of these functions.

Signed-off-by: Simon

drm/drv: use enum drm_minor_type when appropriate

This makes it easier to figure out what the "type" variable can be
set to when reading the implementation of these functions.

Signed-off-by: Simon Ser <contact@emersion.fr>
Reviewed-by:James Zhu <James.Zhu@amd.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Marek Olšák <marek.olsak@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20230714104557.518457-1-contact@emersion.fr

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Documentation: vkms: clarify devres managed reference cleanup

added documentation to drm_dev_unregister clarifying that devres managed
devices allocated with devm_drm_dev_alloc do not require calls

Documentation: vkms: clarify devres managed reference cleanup

added documentation to drm_dev_unregister clarifying that devres managed
devices allocated with devm_drm_dev_alloc do not require calls to
drm_dev_put.

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Brandon Pollack <brpol@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230425080240.3582324-1-brpol@chromium.org

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drm: remove drm_dev_set_unique

Not used by any drivers any more, the only use case in drm_dev_init()
can be inlined now.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Jeffr

drm: remove drm_dev_set_unique

Not used by any drivers any more, the only use case in drm_dev_init()
can be inlined now.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230316082035.567520-2-christian.koenig@amd.com

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drm/debugfs: create device-centered debugfs functions

Introduce the ability to track requests for the addition of DRM debugfs
files at any time and have them added all at once during
drm_dev_registe

drm/debugfs: create device-centered debugfs functions

Introduce the ability to track requests for the addition of DRM debugfs
files at any time and have them added all at once during
drm_dev_register().

Drivers can add DRM debugfs files to a device-managed list and, during
drm_dev_register(), all added files will be created at once.

Now, the drivers can use the functions drm_debugfs_add_file() and
drm_debugfs_add_files() to create DRM debugfs files instead of using the
drm_debugfs_create_files() function.

Co-developed-by: Wambui Karuga <wambui.karugax@gmail.com>
Signed-off-by: Wambui Karuga <wambui.karugax@gmail.com>
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Melissa Wen <mwen@igalia.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20221219120621.15086-2-mcanal@igalia.com

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drm/drv: Make use of local variable driver in drm_dev_register()

There is a local variable that contains dev->driver. Make use of it
instead of "open coding" it.

Signed-off-by: Uwe Kleine-König <u.

drm/drv: Make use of local variable driver in drm_dev_register()

There is a local variable that contains dev->driver. Make use of it
instead of "open coding" it.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20221219183147.1639399-1-u.kleine-koenig@pengutronix.de

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drm: initialize accel framework

Now that we have the accel framework code ready, let's call the
accel functions from all the appropriate places. These places are the
drm module init/exit functions,

drm: initialize accel framework

Now that we have the accel framework code ready, let's call the
accel functions from all the appropriate places. These places are the
drm module init/exit functions, and all the drm_minor handling
functions.

Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Tested-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Reviewed-by: Melissa Wen <mwen@igalia.com>

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drm/drv: Fix potential memory leak in drm_dev_init()

drm_dev_init() will add drm_dev_init_release() as a callback. When
drmm_add_action() failed, the release function won't be added. As the
result,

drm/drv: Fix potential memory leak in drm_dev_init()

drm_dev_init() will add drm_dev_init_release() as a callback. When
drmm_add_action() failed, the release function won't be added. As the
result, the ref cnt added by device_get() in drm_dev_init() won't be put
by drm_dev_init_release(), which leads to the memleak. Use
drmm_add_action_or_reset() instead of drmm_add_action() to prevent
memleak.

unreferenced object 0xffff88810bc0c800 (size 2048):
comm "modprobe", pid 8322, jiffies 4305809845 (age 15.292s)
hex dump (first 32 bytes):
e8 cc c0 0b 81 88 ff ff ff ff ff ff 00 00 00 00 ................
20 24 3c 0c 81 88 ff ff 18 c8 c0 0b 81 88 ff ff $<.............
backtrace:
[<000000007251f72d>] __kmalloc+0x4b/0x1c0
[<0000000045f21f26>] platform_device_alloc+0x2d/0xe0
[<000000004452a479>] platform_device_register_full+0x24/0x1c0
[<0000000089f4ea61>] 0xffffffffa0736051
[<00000000235b2441>] do_one_initcall+0x7a/0x380
[<0000000001a4a177>] do_init_module+0x5c/0x230
[<000000002bf8a8e2>] load_module+0x227d/0x2420
[<00000000637d6d0a>] __do_sys_finit_module+0xd5/0x140
[<00000000c99fc324>] do_syscall_64+0x3f/0x90
[<000000004d85aa77>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: 2cbf7fc6718b ("drm: Use drmm_ for drm_dev_init cleanup")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221101070716.9189-2-shangxiaojing@huawei.com

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drm: fix null-ptr-deref in drm_dev_init_release()

I got a null-ptr-deref report:

[drm:drm_dev_init [drm]] *ERROR* Cannot allocate anonymous inode: -12
==============================================

drm: fix null-ptr-deref in drm_dev_init_release()

I got a null-ptr-deref report:

[drm:drm_dev_init [drm]] *ERROR* Cannot allocate anonymous inode: -12
==================================================================
BUG: KASAN: null-ptr-deref in iput+0x3c/0x4a0
...
Call Trace:
dump_stack_lvl+0x6c/0x8b
kasan_report.cold+0x64/0xdb
__asan_load8+0x69/0x90
iput+0x3c/0x4a0
drm_dev_init_release+0x39/0xb0 [drm]
drm_managed_release+0x158/0x2d0 [drm]
drm_dev_init+0x3a7/0x4c0 [drm]
__devm_drm_dev_alloc+0x55/0xd0 [drm]
mi0283qt_probe+0x8a/0x2b5 [mi0283qt]
spi_probe+0xeb/0x130
...
entry_SYSCALL_64_after_hwframe+0x44/0xae

If drm_fs_inode_new() fails in drm_dev_init(), dev->anon_inode will point
to PTR_ERR(...) instead of NULL. This will result in null-ptr-deref when
drm_fs_inode_free(dev->anon_inode) is called.

drm_dev_init()
drm_fs_inode_new() // fail, dev->anon_inode = PTR_ERR(...)
drm_managed_release()
drm_dev_init_release()
drm_fs_inode_free() // access non-existent anon_inode

Define a temp variable and assign it to dev->anon_inode if the temp
variable is not PTR_ERR.

Fixes: 2cbf7fc6718b ("drm: Use drmm_ for drm_dev_init cleanup")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20211013114139.4042207-1-wanghai38@huawei.com

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drm: Add privacy-screen class (v4)

On some new laptops the LCD panel has a builtin electronic privacy-screen.
We want to export this functionality as a property on the drm connector
object. But ofte

drm: Add privacy-screen class (v4)

On some new laptops the LCD panel has a builtin electronic privacy-screen.
We want to export this functionality as a property on the drm connector
object. But often this functionality is not exposed on the GPU but on some
other (ACPI) device.

This commit adds a privacy-screen class allowing the driver for these
other devices to register themselves as a privacy-screen provider; and
allowing the drm/kms code to get a privacy-screen provider associated
with a specific GPU/connector combo.

Changes in v2:
- Make CONFIG_DRM_PRIVACY_SCREEN a bool which controls if the drm_privacy
code gets built as part of the main drm module rather then making it
a tristate which builds its own module.
- Add a #if IS_ENABLED(CONFIG_DRM_PRIVACY_SCREEN) check to
drm_privacy_screen_consumer.h and define stubs when the check fails.
Together these 2 changes fix several dependency issues.
- Remove module related code now that this is part of the main drm.ko
- Use drm_class as class for the privacy-screen devices instead of
adding a separate class for this

Changes in v3:
- Make the static inline drm_privacy_screen_get_state() stub set sw_state
and hw_state to PRIVACY_SCREEN_DISABLED to squelch an uninitialized
variable warning when CONFIG_DRM_PRIVICAY_SCREEN is not set

Changes in v4:
- Make drm_privacy_screen_set_sw_state() skip calling out to the hw if
hw_state == new_sw_state

Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211005202322.700909-3-hdegoede@redhat.com

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drm: Fix typo in comments

fix typo for drm

v1->v2:
respin with the change "iff ==> implies that"

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll

drm: Fix typo in comments

fix typo for drm

v1->v2:
respin with the change "iff ==> implies that"

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210730132729.376-1-caihuoqing@baidu.com

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drm: Add a prefetching memcpy_from_wc

Reading out of write-combining mapped memory is typically very slow
since the CPU doesn't prefetch. However some archs have special
instructions to do this.

So

drm: Add a prefetching memcpy_from_wc

Reading out of write-combining mapped memory is typically very slow
since the CPU doesn't prefetch. However some archs have special
instructions to do this.

So add a best-effort memcpy_from_wc taking dma-buf-map pointer
arguments that attempts to use a fast prefetching memcpy and
otherwise falls back to ordinary memcopies, taking the iomem tagging
into account.

The code is largely copied from i915_memcpy_from_wc.

Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Christian König <christian.koenig@amd.com>
Suggested-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://lore.kernel.org/r/20210602083818.241793-5-thomas.hellstrom@linux.intel.com
Link: https://patchwork.freedesktop.org/patch/msgid/20210602083818.241793-5-thomas.hellstrom@linux.intel.com

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drm: Mark PCI AGP helpers as legacy

DRM's AGP helpers for PCI are only required by legacy drivers. Put them
behind CONFIG_DRM_LEGACY and add the _legacy_ infix.

Signed-off-by: Thomas Zimmermann <tz

drm: Mark PCI AGP helpers as legacy

DRM's AGP helpers for PCI are only required by legacy drivers. Put them
behind CONFIG_DRM_LEGACY and add the _legacy_ infix.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210507185709.22797-4-tzimmermann@suse.de

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