Passing an object_count of sufficient size will make
object_count * 4 wrap around to be very small, then a later function
will happily iterate off the end of the object_ids array. Using
array_size() will saturate at SIZE_MAX, the kmalloc() will fail and
we'll return an -ENOMEM to the norty userspace.
Fixes: 62884cd386 ("drm: Add four ioctls for managing drm mode object leases [v7]")
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: <stable@vger.kernel.org> # v4.15+
Signed-off-by: Dave Airlie <airlied@redhat.com>
Sending the exact same hotplug event is not great uapi. Luckily the
only already merged implementation of leases (in the -modesetting
driver) doesn't care about what kind of uevent it gets, and
unconditionally processes both hotplug and lease changes. So we can
still adjust the uapi here.
But e.g. weston tries to filter stuff, and I guess others might want
to do that too. Try to make that possible. Cc: stable since it's uapi
adjustement that we want to roll out everywhere.
Michel Dänzer mentioned on irc that -amdgpu also has lease support. It
has the same code flow as -modesetting though, so we can still go
ahead.
v2: Mention -amdgpu (Michel)
Cc: Keith Packard <keithp@keithp.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: stable@vger.kernel.org
Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181129094226.30591-1-daniel.vetter@ffwll.ch
UAPI Changes:
- Add syncobj timeline support to drm.
Cross-subsystem Changes:
- Remove shared fence staging in dma-buf's fence object, and allow
reserving more than 1 fence and add more paranoia when debugging.
- Constify infoframe functions in video/hdmi.
Core Changes:
- Add vkms todo, and a lot of assorted doc fixes.
- Drop transitional helpers and convert drivers to use drm_atomic_helper_shutdown().
- Move atomic state helper functions to drm_atomic_state_helper.[ch]
- Refactor drm selftests, and add new tests.
- DP MST atomic state cleanups.
- Drop EXPORT_SYMBOL from drm leases.
- Lease cleanups and fixes.
- Create render node for vgem.
Driver Changes:
- Fix build failure in imx without fbdev emulation.
- Add rotation quirk for GPD win2 panel.
- Add support for various CDTech panels, Banana Pi Panel, DLC1010GIG,
Olimex LCD-O-LinuXino, Samsung S6D16D0, Truly NT35597 WQXGA,
Himax HX8357D, simulated RTSM AEMv8.
- Add dw_hdmi support to rockchip driver.
- Fix YUV support in vc4.
- Fix resource id handling in virtio.
- Make rockchip use dw-mipi-dsi bridge driver, and add dual dsi support.
- Advertise that tinydrm only supports DRM_FORMAT_MOD_LINEAR.
- Convert many drivers to use atomic helpers, and drm_fbdev_generic_setup().
- Add Mali linear tiled formats, and enable them in the Mali-DP driver.
- Add support for H6 DE3 mixer 0, DW HDMI, HDMI PHY and TCON TOP.
- Assorted driver cleanups and fixes.
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Merge tag 'drm-misc-next-2018-11-07' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
drm-misc-next for v4.21, part 1:
UAPI Changes:
- Add syncobj timeline support to drm.
Cross-subsystem Changes:
- Remove shared fence staging in dma-buf's fence object, and allow
reserving more than 1 fence and add more paranoia when debugging.
- Constify infoframe functions in video/hdmi.
Core Changes:
- Add vkms todo, and a lot of assorted doc fixes.
- Drop transitional helpers and convert drivers to use drm_atomic_helper_shutdown().
- Move atomic state helper functions to drm_atomic_state_helper.[ch]
- Refactor drm selftests, and add new tests.
- DP MST atomic state cleanups.
- Drop EXPORT_SYMBOL from drm leases.
- Lease cleanups and fixes.
- Create render node for vgem.
Driver Changes:
- Fix build failure in imx without fbdev emulation.
- Add rotation quirk for GPD win2 panel.
- Add support for various CDTech panels, Banana Pi Panel, DLC1010GIG,
Olimex LCD-O-LinuXino, Samsung S6D16D0, Truly NT35597 WQXGA,
Himax HX8357D, simulated RTSM AEMv8.
- Add dw_hdmi support to rockchip driver.
- Fix YUV support in vc4.
- Fix resource id handling in virtio.
- Make rockchip use dw-mipi-dsi bridge driver, and add dual dsi support.
- Advertise that tinydrm only supports DRM_FORMAT_MOD_LINEAR.
- Convert many drivers to use atomic helpers, and drm_fbdev_generic_setup().
- Add Mali linear tiled formats, and enable them in the Mali-DP driver.
- Add support for H6 DE3 mixer 0, DW HDMI, HDMI PHY and TCON TOP.
- Assorted driver cleanups and fixes.
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/be7ebd91-edd9-8fa4-4286-1c57e3165113@linux.intel.com
It's lockless, and userspace might chance it underneath us. That's not
really a problem, all userspace gets is a slightly dysfunctional
lease with the current code. But this might change, and gcc might
decide to reload a few too many times, and then boom. So better safe
than sorry.
v2: Remove the now unused lessor_priv argument from validate_lease()
(Keith).
v3: Actually add everything ... silly me.
Cc: Keith Packard <keithp@keithp.com>
Cc: Dave Airlie <airlied@gmail.com>
Acked-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181105101211.22737-1-daniel.vetter@ffwll.ch
I spent a bit of time scratching heads and figuring out why the igts
don't work. Probably useful to keep this work.
Cc: Keith Packard <keithp@keithp.com>
Cc: Dave Airlie <airlied@gmail.com>
Acked-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20181102132543.16486-1-daniel.vetter@ffwll.ch
Leases are entirely implemented within drm.ko, no need to even tempt
drivers into doing nasty things. And if there's really a need, we can
always re-export these again.
Cc: Keith Packard <keithp@keithp.com>
Cc: Dave Airlie <airlied@gmail.com>
Acked-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181102143107.25722-1-daniel.vetter@ffwll.ch
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Merge tag 'drm-next-2018-10-24' of git://anongit.freedesktop.org/drm/drm
Pull drm updates from Dave Airlie:
"This is going to rebuild more than drm as it adds a new helper to
list.h for doing bulk updates. Seemed like a reasonable addition to
me.
Otherwise the usual merge window stuff lots of i915 and amdgpu, not so
much nouveau, and piles of everything else.
Core:
- Adds a new list.h helper for doing bulk list updates for TTM.
- Don't leak fb address in smem_start to userspace (comes with EXPORT
workaround for people using mali out of tree hacks)
- udmabuf device to turn memfd regions into dma-buf
- Per-plane blend mode property
- ref/unref replacements with get/put
- fbdev conflicting framebuffers code cleaned up
- host-endian format variants
- panel orientation quirk for Acer One 10
bridge:
- TI SN65DSI86 chip support
vkms:
- GEM support.
- Cursor support
amdgpu:
- Merge amdkfd and amdgpu into one module
- CEC over DP AUX support
- Picasso APU support + VCN dynamic powergating
- Raven2 APU support
- Vega20 enablement + kfd support
- ACP powergating improvements
- ABGR/XBGR display support
- VCN jpeg support
- xGMI support
- DC i2c/aux cleanup
- Ycbcr 4:2:0 support
- GPUVM improvements
- Powerplay and powerplay endian fixes
- Display underflow fixes
vmwgfx:
- Move vmwgfx specific TTM code to vmwgfx
- Split out vmwgfx buffer/resource validation code
- Atomic operation rework
bochs:
- use more helpers
- format/byteorder improvements
qxl:
- use more helpers
i915:
- GGTT coherency getparam
- Turn off resource streamer API
- More Icelake enablement + DMC firmware
- Full PPGTT for Ivybridge, Haswell and Valleyview
- DDB distribution based on resolution
- Limited range DP display support
nouveau:
- CEC over DP AUX support
- Initial HDMI 2.0 support
virtio-gpu:
- vmap support for PRIME objects
tegra:
- Initial Tegra194 support
- DMA/IOMMU integration fixes
msm:
- a6xx perf improvements + clock prefix
- GPU preemption optimisations
- a6xx devfreq support
- cursor support
rockchip:
- PX30 support
- rgb output interface support
mediatek:
- HDMI output support on mt2701 and mt7623
rcar-du:
- Interlaced modes on Gen3
- LVDS on R8A77980
- D3 and E3 SoC support
hisilicon:
- misc fixes
mxsfb:
- runtime pm support
sun4i:
- R40 TCON support
- Allwinner A64 support
- R40 HDMI support
omapdrm:
- Driver rework changing display pipeline ordering to use common code
- DMM memory barrier and irq fixes
- Errata workarounds
exynos:
- out-bridge support for LVDS bridge driver
- Samsung 16x16 tiled format support
- Plane alpha and pixel blend mode support
tilcdc:
- suspend/resume update
mali-dp:
- misc updates"
* tag 'drm-next-2018-10-24' of git://anongit.freedesktop.org/drm/drm: (1382 commits)
firmware/dmc/icl: Add missing MODULE_FIRMWARE() for Icelake.
drm/i915/icl: Fix signal_levels
drm/i915/icl: Fix DDI/TC port clk_off bits
drm/i915/icl: create function to identify combophy port
drm/i915/gen9+: Fix initial readout for Y tiled framebuffers
drm/i915: Large page offsets for pread/pwrite
drm/i915/selftests: Disable shrinker across mmap-exhaustion
drm/i915/dp: Link train Fallback on eDP only if fallback link BW can fit panel's native mode
drm/i915: Fix intel_dp_mst_best_encoder()
drm/i915: Skip vcpi allocation for MSTB ports that are gone
drm/i915: Don't unset intel_connector->mst_port
drm/i915: Only reset seqno if actually idle
drm/i915: Use the correct crtc when sanitizing plane mapping
drm/i915: Restore vblank interrupts earlier
drm/i915: Check fb stride against plane max stride
drm/amdgpu/vcn:Fix uninitialized symbol error
drm: panel-orientation-quirks: Add quirk for Acer One 10 (S1003)
drm/amd/amdgpu: Fix debugfs error handling
drm/amdgpu: Update gc_9_0 golden settings.
drm/amd/powerplay: update PPtable with DC BTC and Tvr SocLimit fields
...
fd_install() moves the reference given to it into the file descriptor table
of the current process. If the current process is multithreaded, then
immediately after fd_install(), another thread can close() the file
descriptor and cause the file's resources to be cleaned up.
Since the reference to "lessee" is held by the file, we must not access
"lessee" after the fd_install() call.
As far as I can tell, to reach this codepath, the caller must have an open
file descriptor to a DRI device in master mode. I'm not sure what the
requirements for that are.
Signed-off-by: Jann Horn <jannh@google.com>
Fixes: 62884cd386 ("drm: Add four ioctls for managing drm mode object leases [v7]")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20181001153117.216923-1-jannh@google.com
If the ioctl is not supported on a particular piece of HW/driver
combination, report ENOTSUP (aka EOPNOTSUPP) so that it can be easily
distinguished from both the lack of the ioctl and from a regular invalid
parameter.
v2: Across all the kms ioctls we had a mixture of reporting EINVAL,
ENODEV and a few ENOTSUPP (most where EINVAL) for a failed
drm_core_check_feature(). Update everybody to report ENOTSUPP.
v3: ENOTSUPP is an internal errno! It's value (524) does not correspond
to a POSIX errno, the one we want is ENOTSUP. However,
uapi/asm-generic/errno.h doesn't include ENOTSUP but man errno says
"ENOTSUP and EOPNOTSUPP have the same value on Linux,
but according to POSIX.1 these error values should be
distinct."
so use EOPNOTSUPP as its equivalent.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> #v2
Link: https://patchwork.freedesktop.org/patch/msgid/20180913192050.24812-1-chris@chris-wilson.co.uk
it's exactly the same thing as
dentry_open(&file->f_path, file->f_flags, file->f_cred)
... and rename it to file_clone_open(), while we are at it.
'filp' naming convention is bogus; sure, it's "file pointer",
but we generally don't do that kind of Hungarian notation.
Some of the instances have too many callers to touch, but this
one has only two, so let's sanitize it while we can...
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Failure of ->open() should *not* be followed by fput(). Fixed by
using filp_clone_open(), which gets the cleanups right.
Cc: stable@vger.kernel.org
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
drivers/gpu/drm/drm_lease.c:56: warning: No description found for parameter 'lessee_id'
drivers/gpu/drm/drm_lease.c:56: warning: Excess function parameter 'id' description in '_drm_find_lessee'
drivers/gpu/drm/drm_lease.c:114: warning: No description found for parameter 'file_priv'
drivers/gpu/drm/drm_lease.c:114: warning: Excess function parameter 'master' description in '_drm_lease_held'
drivers/gpu/drm/drm_lease.c:134: warning: No description found for parameter 'file_priv'
drivers/gpu/drm/drm_lease.c:134: warning: Excess function parameter 'master' description in 'drm_lease_held'
drivers/gpu/drm/drm_lease.c:158: warning: No description found for parameter 'crtcs_in'
drivers/gpu/drm/drm_lease.c:158: warning: Excess function parameter 'crtcs' description in 'drm_lease_filter_crtcs'
drivers/gpu/drm/drm_lease.c:311: warning: No description found for parameter 'top'
drivers/gpu/drm/drm_lease.c:311: warning: Excess function parameter 'master' description in '_drm_lease_revoke'
drivers/gpu/drm/drm_lease.c:494: warning: No description found for parameter 'lessor_priv'
drivers/gpu/drm/drm_lease.c:494: warning: Excess function parameter 'file_priv' description in 'drm_mode_create_lease_ioctl'
drivers/gpu/drm/drm_lease.c:672: warning: No description found for parameter 'lessee_priv'
drivers/gpu/drm/drm_lease.c:672: warning: Excess function parameter 'file_priv' description in 'drm_mode_get_lease_ioctl'
drivers/gpu/drm/drm_lease.c:733: warning: No description found for parameter 'lessor_priv'
drivers/gpu/drm/drm_lease.c:733: warning: Excess function parameter 'file_priv' description in 'drm_mode_revoke_lease_ioctl'
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180208110817.30057-1-chris@chris-wilson.co.uk
Patch bd36d3bab2 fixed a deadlock in the
failure path of drm_lease_create. This made the partially initialized
lease object visible for a short window of time.
To avoid having the lessee state appear transiently, I've rearranged
the code so that the lessor fields are not filled in until the
parameters are all validated and the function will succeed.
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171221065424.1304-1-keithp@keithp.com
This case can been seen when creating the lease with the same objects passed.
[ 605.515097] 2 locks held by testapp/3337:
[ 605.519027] #0: (&dev->mode_config.idr_mutex){......}, at: [<ffff0000085f1664>] drm_mode_create_lease_ioctl+0x384/0x858
[ 605.530045] #1: (&dev->mode_config.idr_mutex){......}, at: [<ffff0000085f11bc>] drm_lease_destroy+0x2c/0x110
Which was causing the process to hang:
[ 605.398827] [<ffff0000080856cc>] __switch_to+0x94/0xa8
[ 605.404030] [<ffff000008c05d00>] __schedule+0x1b0/0x698
[ 605.409322] [<ffff000008c06224>] schedule+0x3c/0xa8
[ 605.414260] [<ffff000008c06628>] schedule_preempt_disabled+0x20/0x38
[ 605.420677] [<ffff000008c07370>] mutex_lock_nested+0x158/0x340
[ 605.426572] [<ffff0000085f11bc>] drm_lease_destroy+0x2c/0x110
[ 605.432389] [<ffff0000085cecf0>] drm_master_put+0xc0/0xc8
[ 605.437845] [<ffff0000085f175c>] drm_mode_create_lease_ioctl+0x47c/0x858
[ 605.444612] [<ffff0000085d4460>] drm_ioctl+0x198/0x448
[ 605.449811] [<ffff000008201134>] do_vfs_ioctl+0xa4/0x748
[ 605.455192] [<ffff000008201864>] SyS_ioctl+0x8c/0xa0
[ 605.460216] [<ffff000008082f4c>] __sys_trace_return+0x0/0x4
drm_mode_create_lease_ioctl() calls drm_lease_create() which acquires a lock
on dev->mode_config.idr_mutex. In case of failure, drm_lease_create() calls
drm_master_put() which in turn tries to acquire the same lock when calling
drm_lease_destroy().
v2: - Reverse the order at exit in case of fail, so that unlocking takes place
before dropping the reference.
- Include detail information about deadlock (Daniel Vetter)
Signed-off-by: Marius Vlad <marius-cristian.vlad@nxp.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171213181048.32719-1-marius-cristian.vlad@nxp.com
drm_mode_create_lease
Creates a lease for a list of drm mode objects, returning an
fd for the new drm_master and a 64-bit identifier for the lessee
drm_mode_list_lesees
List the identifiers of the lessees for a master file
drm_mode_get_lease
List the leased objects for a master file
drm_mode_revoke_lease
Erase the set of objects managed by a lease.
This should suffice to at least create and query leases.
Changes for v2 as suggested by Daniel Vetter <daniel.vetter@ffwll.ch>:
* query ioctls only query the master associated with
the provided file.
* 'mask_lease' value has been removed
* change ioctl has been removed.
Changes for v3 suggested in part by Dave Airlie <airlied@gmail.com>
* Add revoke ioctl.
Changes for v4 suggested by Dave Airlie <airlied@gmail.com>
* Expand on the comment about the magic use of &drm_lease_idr_object
* Pad lease ioctl structures to align on 64-bit boundaries
Changes for v5 suggested by Dave Airlie <airlied@gmail.com>
* Check for non-negative object_id in create_lease to avoid debug
output from the kernel.
Changes for v6 provided by Dave Airlie <airlied@gmail.com>
* For non-universal planes add primary/cursor planes to lease
If we aren't exposing universal planes to this userspace client,
and it requests a lease on a crtc, we should implicitly export the
primary and cursor planes for the crtc.
If the lessee doesn't request universal planes, it will just see
the crtc, but if it does request them it will then see the plane
objects as well.
This also moves the object look ups earlier as a side effect, so
we'd exit the ioctl quicker for non-existant objects.
* Restrict leases to crtc/connector/planes.
This only allows leasing for objects we wish to allow.
Changes for v7 provided by Dave Airlie <airlied@gmail.com>
* Check pad args are 0
* Check create flags and object count are valid.
* Check return from fd allocation
* Refactor lease idr setup and add some simple validation
* Use idr_mutex uniformly (Keith)
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This provides new data structures to hold "lease" information about
drm mode setting objects, and provides for creating new drm_masters
which have access to a subset of the available drm resources.
An 'owner' is a drm_master which is not leasing the objects from
another drm_master, and hence 'owns' them.
A 'lessee' is a drm_master which is leasing objects from some other
drm_master. Each lessee holds the set of objects which it is leasing
from the lessor.
A 'lessor' is a drm_master which is leasing objects to another
drm_master. This is the same as the owner in the current code.
The set of objects any drm_master 'controls' is limited to the set of
objects it leases (for lessees) or all objects (for owners).
Objects not controlled by a drm_master cannot be modified through the
various state manipulating ioctls, and any state reported back to user
space will be edited to make them appear idle and/or unusable. For
instance, connectors always report 'disconnected', while encoders
report no possible crtcs or clones.
The full list of lessees leasing objects from an owner (either
directly, or indirectly through another lessee), can be searched from
an idr in the drm_master of the owner.
Changes for v2 as suggested by Daniel Vetter <daniel.vetter@ffwll.ch>:
* Sub-leasing has been disabled.
* BUG_ON for lock checking replaced with lockdep_assert_held
* 'change' ioctl has been removed.
* Leased objects can always be controlled by the lessor; the
'mask_lease' flag has been removed
* Checking for leased status has been simplified, replacing
the drm_lease_check function with drm_lease_held.
Changes in v3, some suggested by Dave Airlie <airlied@gmail.com>
* Add revocation. This allows leases to be effectively revoked by
removing all of the objects they have access to. The lease itself
hangs around as it's hanging off a file.
* Free the leases IDR when the master is destroyed
* _drm_lease_held should look at lessees, not lessor
* Allow non-master files to check for lease status
Changes in v4, suggested by Dave Airlie <airlied@gmail.com>
* Formatting and whitespace changes
Changes in v5 (airlied)
* check DRIVER_MODESET before lease destroy call
* check DRIVER_MODESET for lease revoke (Chris)
* Use idr_mutex uniformly for all lease elements of struct drm_master. (Keith)
Signed-off-by: Keith Packard <keithp@keithp.com>
Matthew Wilcox