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>
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>
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
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
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>
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>
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>
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
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
UAPI Changes:
* connector: Support analog-TV mode property
* media: Add MEDIA_BUS_FMT_RGB565_1X24_CPADHI,
MEDIA_BUS_FMT_RGB666_1X18 and MEDIA_BUS_FMT_RGB666_1X24_CPADHI
Cross-subsystem Changes:
* dma-buf: Documentation fixes
* i2c: Introduce i2c_client_get_device_id() helper
Core Changes:
* Improve support for analog TV output
* bridge: Remove unused drm_bridge_chain functions
* debugfs: Add per-device helpers and convert various DRM drivers
* dp-mst: Various fixes
* fbdev emulation: Always pick 32 bpp as default
* KUnit: Add tests for managed helpers; Various cleanups
* panel-orientation: Add quirks for Lenovo Yoga Tab 3 X90F and DynaBook K50
* TTM: Open-code ttm_bo_wait() and remove the helper
Driver Changes:
* Fix preferred depth and bpp values throughout DRM drivers
* Remove #CONFIG_PM guards throughout DRM drivers
* ast: Various fixes
* bridge: Implement i2c's probe_new in various drivers; Fixes; ite-it6505:
Locking fixes, Cache EDID data; ite-it66121: Support IT6610 chip,
Cleanups; lontium-tl9611: Fix HDMI on DragonBoard 845c; parade-ps8640:
Use atomic bridge functions
* gud: Convert to DRM shadow-plane helpers; Perform flushing synchronously
during atomic update
* ili9486: Support 16-bit pixel data
* imx: Split off IPUv3 driver; Various fixes
* mipi-dbi: Convert to DRM shadow-plane helpers plus rsp driver changes;i
Support separate I/O-voltage supply
* mxsfb: Depend on ARCH_MXS or ARCH_MXC
* omapdrm: Various fixes
* panel: Use ktime_get_boottime() to measure power-down delay in various
drivers; Fix auto-suspend delay in various drivers; orisetech-ota5601a:
Add support
* sprd: Cleanups
* sun4i: Convert to new TV-mode property
* tidss: Various fixes
* v3d: Various fixes
* vc4: Convert to new TV-mode property; Support Kunit tests; Cleanups;
dpi: Support RGB565 and RGB666 formats; dsi: Convert DSI driver to
bridge
* virtio: Improve tracing
* vkms: Support small cursors in IGT tests; Various fixes
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Merge tag 'drm-misc-next-2023-01-03' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
drm-misc-next for v6.3:
UAPI Changes:
* connector: Support analog-TV mode property
* media: Add MEDIA_BUS_FMT_RGB565_1X24_CPADHI,
MEDIA_BUS_FMT_RGB666_1X18 and MEDIA_BUS_FMT_RGB666_1X24_CPADHI
Cross-subsystem Changes:
* dma-buf: Documentation fixes
* i2c: Introduce i2c_client_get_device_id() helper
Core Changes:
* Improve support for analog TV output
* bridge: Remove unused drm_bridge_chain functions
* debugfs: Add per-device helpers and convert various DRM drivers
* dp-mst: Various fixes
* fbdev emulation: Always pick 32 bpp as default
* KUnit: Add tests for managed helpers; Various cleanups
* panel-orientation: Add quirks for Lenovo Yoga Tab 3 X90F and DynaBook K50
* TTM: Open-code ttm_bo_wait() and remove the helper
Driver Changes:
* Fix preferred depth and bpp values throughout DRM drivers
* Remove #CONFIG_PM guards throughout DRM drivers
* ast: Various fixes
* bridge: Implement i2c's probe_new in various drivers; Fixes; ite-it6505:
Locking fixes, Cache EDID data; ite-it66121: Support IT6610 chip,
Cleanups; lontium-tl9611: Fix HDMI on DragonBoard 845c; parade-ps8640:
Use atomic bridge functions
* gud: Convert to DRM shadow-plane helpers; Perform flushing synchronously
during atomic update
* ili9486: Support 16-bit pixel data
* imx: Split off IPUv3 driver; Various fixes
* mipi-dbi: Convert to DRM shadow-plane helpers plus rsp driver changes;i
Support separate I/O-voltage supply
* mxsfb: Depend on ARCH_MXS or ARCH_MXC
* omapdrm: Various fixes
* panel: Use ktime_get_boottime() to measure power-down delay in various
drivers; Fix auto-suspend delay in various drivers; orisetech-ota5601a:
Add support
* sprd: Cleanups
* sun4i: Convert to new TV-mode property
* tidss: Various fixes
* v3d: Various fixes
* vc4: Convert to new TV-mode property; Support Kunit tests; Cleanups;
dpi: Support RGB565 and RGB666 formats; dsi: Convert DSI driver to
bridge
* virtio: Improve tracing
* vkms: Support small cursors in IGT tests; Various fixes
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
From: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/Y7QIwlfElAYWxRcR@linux-uq9g
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
subsystem, which is part of the DRM subsystem.
The patches:
- Add a new directory at drivers/accel.
- Add a new major (261) for compute accelerators.
- Add a new DRM minor type for compute accelerators.
- Integrate the accel core code with DRM core code.
- Add documentation for the accel subsystem.
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Merge tag 'drm-accel-2022-11-22' of https://git.kernel.org/pub/scm/linux/kernel/git/ogabbay/accel into drm-next
This tag contains the patches that add the new compute acceleration
subsystem, which is part of the DRM subsystem.
The patches:
- Add a new directory at drivers/accel.
- Add a new major (261) for compute accelerators.
- Add a new DRM minor type for compute accelerators.
- Integrate the accel core code with DRM core code.
- Add documentation for the accel subsystem.
Signed-off-by: Dave Airlie <airlied@redhat.com>
some acks from the list (some are in the patch series):
Acked-by: Daniel Stone <daniels@collabora.com>
Acked-by: Sonal Santan <sonal.santan@amd.com>
Acked-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Tested-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
From: Oded Gabbay <ogabbay@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20221122112222.GA352082@ogabbay-vm-u20.habana-labs.com
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>
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
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
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
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
Invalidate all BOs CPU mappings once device is removed.
v3: Move the code from TTM into drm_dev_unplug
Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/414809/
Signed-off-by: Christian König <christian.koenig@amd.com>
Now that the legacy PCI support code doesn't need to write to the
drm_driver structure, it can be treated as const through the whole DRM
core, unconditionally. This allows declaring the structure as const in
all drivers, removing one possible attack vector.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
It's nice if a big function/ioctl table like this is const. Only
downside here is that we need a few more #ifdef to paper over the
differences when CONFIG_DRM_LEGACY is enabled. Maybe provides more
motivation to sunset that horror show :-)
v2:
- Fix super important checkpatch warning (Sam)
- Update the kerneldoc example too (Sam)
Acked-by: Maxime Ripard <mripard@kernel.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Sam Ravnborg <sam@ravnborg.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@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201104100425.1922351-4-daniel.vetter@ffwll.ch
Following functions are only used internally, not by drivers:
- devm_drm_dev_init
Also, now that we have a very slick and polished way to allocate a
drm_device with devm_drm_dev_alloc, update all the docs to reflect the
new reality. Mostly this consists of deleting old and misleading
hints. Two main ones:
- it is no longer required that the drm_device base class is first in
the structure. devm_drm_dev_alloc can cope with it being anywhere
- obviously embedded now strongly recommends using devm_drm_dev_alloc
v2: Fix typos (Noralf)
v3: Split out the removal of drm_dev_init, that's blocked on some
discussions on how to convert vgem/vkms/i915-selftests. Adjust commit
message to reflect that.
Cc: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Noralf Trønnes <noralf@tronnes.org> (v2)
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Luben Tuikov <luben.tuikov@amd.com>
Cc: amd-gfx@lists.freedesktop.org
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200902072627.3617301-1-daniel.vetter@ffwll.ch
Fix below warnings reported by coccicheck:
./drivers/gpu/drm/drm_drv.c:819:2-7: WARNING: NULL check before some freeing functions is not needed.
Fixes: 5dad34f3c444 ("drm: Cleanups after drmm_add_final_kfree rollout")
Signed-off-by: Li Heng <liheng40@huawei.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1595474863-33112-1-git-send-email-liheng40@huawei.com
Add a new macro helper to combine the usual init sequence in drivers,
consisting of a kzalloc + devm_drm_dev_init + drmm_add_final_kfree
triplet. This allows us to remove the rather unsightly
drmm_add_final_kfree from all currently merged drivers.
The kerneldoc is only added for this new function. Existing kerneldoc
and examples will be udated at the very end, since once all drivers
are converted over to devm_drm_dev_alloc we can unexport a lot of
interim functions and make the documentation for driver authors a lot
cleaner and less confusing. There will be only one true way to
initialize a drm_device at the end of this, which is going to be
devm_drm_dev_alloc.
v2:
- Actually explain what this is for in the commit message (Sam)
- Fix checkpatch issues (Sam)
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200415074034.175360-2-daniel.vetter@ffwll.ch
All collected together to provide a consistent story in one patch,
instead of the somewhat bumpy refactor-evolution leading to this.
Also some thoughts on what the next steps could be:
- Create a macro called devm_drm_dev_alloc() which essentially wraps
the kzalloc(); devm_drm_dev_init(); drmm_add_final_kfree() combo.
Needs to be a macro since we'll have to do some typeof trickery and
casting to make this fully generic for all drivers that embed struct
drm_device into their own thing.
- A lot of the simple drivers now have essentially just
drm_dev_unplug(); drm_atomic_helper_shutdown(); as their
$bus_driver->remove hook. We could create a devm_mode_config_reset
which sets drm_atomic_helper_shutdown as it's cleanup action, and a
devm_drm_dev_register with drm_dev_unplug as it's cleanup action,
and simple drivers wouldn't have a need for a ->remove function at
all, and we could delete them.
- For more complicated drivers we need drmm_ versions of a _lot_ more
things. All the userspace visible objects (crtc, plane, encoder,
crtc), anything else hanging of those (maybe a drmm_get_edid, at
least for panels and other built-in stuff).
Also some more thoughts on why we're not reusing devm_ with maybe a
fake struct device embedded into the drm_device (we can't use the
kdev, since that's in each drm_minor).
- Code review gets extremely tricky, since every time you see a devm_
you need to carefully check whether the fake device (with the
drm_device lifetim) or the real device (with the lifetim of the
underlying physical device and driver binding) are used. That's not
going to help at all, and we have enormous amounts of drivers who
use devm_ where they really shouldn't. Having different types makes
sure the compiler type checks this for us and ensures correctness.
- The set of functions are very much non-overlapping. E.g.
devm_ioremap makes total sense, drmm_ioremap has the wrong lifetime,
since hw resources need to be cleaned out at driver unbind and wont
outlive that like a drm_device. Similar, but other way round for
drmm_connector_init (which is the only correct version, devm_ for
drm_connector is just buggy). Simply not having the wrong version
again prevents bugs.
Finally I guess this opens a huge todo for all the drivers. I'm
semi-tempted to do a tree-wide s/devm_kzalloc/drmm_kzalloc/ since most
likely that'll fix an enormous amount of bugs and most likely not
cause any issues at all (aside from maybe holding onto memory slightly
too long).
v2:
- Doc improvements from Laurent.
- Also add kerneldoc for the new drmm_add_action_or_reset.
v3:
- Remove kerneldoc for drmm_remove_action.
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
fixup docs
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-52-daniel.vetter@ffwll.ch
drm_mode_config_cleanup is idempotent, so no harm in calling this
twice. This allows us to gradually switch drivers over by removing
explicit drm_mode_config_cleanup calls.
With this step it's now also possible that (at least for simple
drivers) automatic resource cleanup can be done correctly without a
drm_driver->release hook. Therefore allow this now in
devm_drm_dev_init().
Also with drmm_ explicit drm_driver->release hooks are kinda not the
best option: Drivers can always just register their current release
hook with drmm_add_action, but even better they could split them up to
simplify the unwinding for the driver load failure case. So deprecate
that hook to discourage future users.
v2: Fixup the example in the kerneldoc too.
v3:
- For paranoia, double check that minor->dev == dev in the release
hook, because I botched the pointer math in the drmm library.
- Call drm_mode_config_cleanup when drmm_add_action fails, we'd be
missing some mutex_destroy and ida_cleanup otherwise (Laurent)
v4: Add a drmm_add_action_or_reset (like devm_ has) to encapsulate this
pattern (Noralf).
v5: Fix oversight in the new drmm_add_action_or_reset macro (Noralf)
v4: Review from Sam:
- drmm_mode_config_init wrapper (also suggested by Thomas)
- improve commit message, explain better why ->relase is deprecated
v5:
- Make drmm_ the main function, with the old one as compat wrapper
(Sam)
- Add FIXME comments to drm_mode_config_cleanup/init() that drivers
shouldn't use these anymore.
- Move drmm_add_action_or_reset helper to an earlier patch.
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: "Noralf Trønnes" <noralf@tronnes.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-27-daniel.vetter@ffwll.ch
Nothing special here, except that this is the first time that we
automatically clean up something that's initialized with an explicit
driver call. But the cleanup was done at the very end of the release
sequence for all drivers, and that's still the case. At least without
more uses of drmm_ through explicit driver calls.
Also for this one we need drmm_kcalloc, so lets add those.
The motivation here is to allow us to remove the explicit calls to
drm_dev_fini() from all drivers.
v2: Sort includes (Laurent)
v3: Motivate the change in the commit message better (Sam)
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-25-daniel.vetter@ffwll.ch
The cleanup here is somewhat tricky, since we can't tell apart the
allocated minor index from 0. So register a cleanup action first, and
if the index allocation fails, unregister that cleanup action again to
avoid bad mistakes.
The kdev for the minor already handles NULL, so no problem there.
Hence add drmm_remove_action() to the drm_managed library.
v2: Make pointer math around void ** consistent with what Laurent
suggested.
v3: Use drmm_add_action_or_reset and remove drmm_remove_action. Noticed
because of some questions from Thomas. This also means we need to move
the drmm_add_action_or_reset helper earlier in the series.
v4: Uh ... fix slightly embarrassing bug CI spotted.
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200324203936.3330994-1-daniel.vetter@ffwll.ch
Well for the simple stuff at least, vblank, gem and minor cleanup I
want to further split up as a demonstration.
v2: We need to clear drm_device->dev otherwise the debug drm printing
after our cleanup hook (e.g. in drm_manged_release) will chase
released memory and result in a use-after-free. Not really pretty, but
oh well.
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-22-daniel.vetter@ffwll.ch
We need to add a drmm_kstrdup for this, but let's start somewhere.
This is not exactly perfect onion unwinding, but it's jsut a kfree so
doesn't really matter at all.
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-21-daniel.vetter@ffwll.ch
A few things:
- Update the example driver in the documentation.
- We can drop the old kfree in drm_dev_release.
- Add a WARN_ON check in drm_dev_register to make sure everyone calls
drmm_add_final_kfree and there's no leaks.
v2: Restore the full cleanup, I accidentally left some moved code
behind when fixing the bisectability of the series.
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-20-daniel.vetter@ffwll.ch
I also did a full review of all callers, and only the xen driver
forgot to call drm_dev_put in the failure path. Fix that up too.
v2: I noticed that xen has a drm_driver.release hook, and uses
drm_dev_alloc(). We need to remove the kfree from
xen_drm_drv_release().
bochs also has a release hook, but leaked the drm_device ever since
commit 0a6659bdc5e8221da99eebb176fd9591435e38de
Author: Gerd Hoffmann <kraxel@redhat.com>
Date: Tue Dec 17 18:04:46 2013 +0100
drm/bochs: new driver
This patch here fixes that leak.
Same for virtio, started leaking with
commit b1df3a2b24a917f8853d43fe9683c0e360d2c33a
Author: Gerd Hoffmann <kraxel@redhat.com>
Date: Tue Feb 11 14:58:04 2020 +0100
drm/virtio: add drm_driver.release callback.
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Cc: xen-devel@lists.xenproject.org
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Cc: xen-devel@lists.xenproject.org
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-5-daniel.vetter@ffwll.ch
We have lots of these. And the cleanup code tends to be of dubious
quality. The biggest wrong pattern is that developers use devm_, which
ties the release action to the underlying struct device, whereas
all the userspace visible stuff attached to a drm_device can long
outlive that one (e.g. after a hotunplug while userspace has open
files and mmap'ed buffers). Give people what they want, but with more
correctness.
Mostly copied from devres.c, with types adjusted to fit drm_device and
a few simplifications - I didn't (yet) copy over everything. Since
the types don't match code sharing looked like a hopeless endeavour.
For now it's only super simplified, no groups, you can't remove
actions (but kfree exists, we'll need that soon). Plus all specific to
drm_device ofc, including the logging. Which I didn't bother to make
compile-time optional, since none of the other drm logging is compile
time optional either.
One tricky bit here is the chicken&egg between allocating your
drm_device structure and initiliazing it with drm_dev_init. For
perfect onion unwinding we'd need to have the action to kfree the
allocation registered before drm_dev_init registers any of its own
release handlers. But drm_dev_init doesn't know where exactly the
drm_device is emebedded into the overall structure, and by the time it
returns it'll all be too late. And forcing drivers to be able clean up
everything except the one kzalloc is silly.
Work around this by having a very special final_kfree pointer. This
also avoids troubles with the list head possibly disappearing from
underneath us when we release all resources attached to the
drm_device.
v2: Do all the kerneldoc at the end, to avoid lots of fairly pointless
shuffling while getting everything into shape.
v3: Add static to add/del_dr (Neil)
Move typo fix to the right patch (Neil)
v4: Enforce contract for drmm_add_final_kfree:
Use ksize() to check that the drm_device is indeed contained somewhere
in the final kfree(). Because we need that or the entire managed
release logic blows up in a pile of use-after-frees. Motivated by a
discussion with Laurent.
v5: Review from Laurent:
- %zu instead of casting size_t
- header guards
- sorting of includes
- guarding of data assignment if we didn't allocate it for a NULL
pointer
- delete spurious newline
- cast void* data parameter correctly in ->release call, no idea how
this even worked before
v6: Review from Sam
- Add the kerneldoc for the managed sub-struct back in, even if it
doesn't show up in the generated html somehow.
- Explain why __always_inline.
- Fix bisectability around the final kfree() in drm_dev_relase(). This
is just interim code which will disappear again.
- Some whitespace polish.
- Add debug output when drmm_add_action or drmm_kmalloc fail.
v7: My bisectability fix wasn't up to par as noticed by smatch.
v8: Remove unecessary {} around if else
v9: Use kstrdup_const, which requires kfree_const and introducing a free_dr()
helper (Thomas).
v10: kfree_const goes boom on the plain "kmalloc" assignment, somehow
we need to wrap that in kstrdup_const() too!! Also renumber revision
log, I somehow reset it midway thruh.
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Neil Armstrong <narmstrong@baylibre.com
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200324124540.3227396-1-daniel.vetter@ffwll.ch
The docs say possible_clones should always include the encoder itself.
Since most drivers don't want to deal with the complexities of cloning
let's allow them to set possible_clones=0 and instead we'll fix that
up in the core.
We can't put this special case into drm_encoder_init() because drivers
will have to fill up possible_clones after adding all the relevant
encoders. Otherwise they wouldn't know the proper encoder indexes to
use. So we'll just do it just before registering the device.
v2: Don't set the bit if possible_clones!=0 so that the
validation (coming soon) will WARN (Thomas)
Fix up the docs to allow possible_clones==0 (Daniel)
.late_register() is too late, introduce drm_mode_config_validate()
which gets called _before_ we register the char device (Daniel)
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211162208.16224-2-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This catches the majority of drivers (unfortunately not if we take
users into account, because all the big drivers have at least a
lastclose hook).
With the prep patches out of the way all drm state is fully protected
and either prevents or can deal with the races from dropping the BKL
around open/close. The only thing left to audit are the various driver
hooks - by keeping the BKL around if any of them are set we have a
very simple cop-out!
Note that one of the biggest prep pieces to get here was making
dev->open_count atomic, which was done in
commit 7e13ad896484a0165a68197a2e64091ea28c9602
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Fri Jan 24 13:01:07 2020 +0000
drm: Avoid drm_global_mutex for simple inc/dec of dev->open_count
v2:
- Rebase and fix locking in drm_open() (Chris)
- Indentation fix in drm_release
- Typo fix in the commit message (Sam)
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200204150146.2006481-6-daniel.vetter@ffwll.ch
We want to only take the BKL on crap drivers, but to know whether
we have a crap driver we first need to look it up. Split this shuffle
out from the main BKL-disabling patch, for more clarity. Historical
aside: When the kernel-wide BKL was removed, it was replaced by
drm_global_mutex within the scope of the drm subsystem hence why these
two things are (almost) interchangeable as concepts here.
Since the minors are refcounted drm_minor_acquire is purely internal
and this does not have a driver visible effect.
v2: Push the locking even further into drm_open(), suggested by Chris.
This gives us more symmetry with drm_release(), and maybe a futuer
avenue where we make drm_global_mutex locking (partially) opt-in like
with drm_release_noglobal().
v3:
- Actually push this stuff correctly, don't unlock twice (Chris)
- Fix typo on commit message, plus explain why BKL = drm_global_mutex
(Sam)
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200204150146.2006481-5-daniel.vetter@ffwll.ch
In drm_dev_init, parent is checked for NULL via assert after
checked in devm_drm_dev_init(). The patch removes the duplicate
check and replaces the assertion with WARN_ON. Further, it returns
-EINVAL consistent with the usage in devm_drm_dev_init.
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20191215194345.4679-1-pakki001@umn.edu
We haven't done any backmerge for a while due to the merge window, and it
starts to become an issue for komeda. Let's bring 5.4-rc1 in.
Signed-off-by: Maxime Ripard <mripard@kernel.org>
