As mentioned in the previous commit, we currently prevent new modesets
on recently-removed MST connectors by returning no encoder from our
->best_encoder() callback once the MST port has disappeared. This is
wrong however, because it prevents legacy modesetting users from being
able to disable CRTCs on MST connectors after the connector's respective
topology has disappeared.
So, fix this by instead by just always returning a valid encoder.
Changes since v2:
- Remove usage of atomic MST helper for now, since that got replaced
with a much simpler solution
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Ben Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20181008232437.5571-3-lyude@redhat.com
This was only added for the drm's fbdev emulation support, so that it
would try harder to show the Oops.
Unfortunately this never really worked reliably, and in practice ended
up pushing the real Oops off the screen due to plentyfull locking,
sleep-while-atomic and other issues. So we removed all that support
from the fbdev emulation a while back. Aside: We've also removed the
kgdb support, for similar reasons.
Since it's such a small patch I figured I don't split this up into the
usual 3-phase removal.
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Alexander Kapshuk <alexander.kapshuk@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: David Lechner <david@lechnology.com>
Cc: nouveau@lists.freedesktop.org
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180822085405.10787-1-daniel.vetter@ffwll.ch
We have a bunch of neat little macros all over the place which should
move to kernel.h. But some of them died in bikesheds on lkml, and we
need a decent home for them.
Start out by moving the for_each_if macro there.
v2: Rename to drm_util.h instead (Dave&Sean)
Cc: Sean Paul <seanpaul@chromium.org>
Acked-by: Sean Paul <seanpaul@chromium.org>
Cc: Dave Airlie <airlied@gmail.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180905135711.28370-1-daniel.vetter@ffwll.ch
Core Changes:
- add support for DisplayPort CEC-Tunneling-over-AUX (Hans Verkuil)
- more doc updates (Daniel Vetter)
- fourcc: Add is_yuv field to drm_format_info (Ayan Kumar Halder)
- dma-buf: correctly place BUG_ON (Michel Dänzer)
Driver Changes:
- more vkms support(Rodrigo Siqueira)
- many fixes and small improments to all drivers
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Merge tag 'drm-misc-next-2018-07-18' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
drm-misc-next for 4.19:
Core Changes:
- add support for DisplayPort CEC-Tunneling-over-AUX (Hans Verkuil)
- more doc updates (Daniel Vetter)
- fourcc: Add is_yuv field to drm_format_info (Ayan Kumar Halder)
- dma-buf: correctly place BUG_ON (Michel Dänzer)
Driver Changes:
- more vkms support(Rodrigo Siqueira)
- many fixes and small improments to all drivers
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180718200826.GA20165@juma
Workaround for issues seen on systems with large amounts of RAM, caused
by display not supporting the same physical address limits as the other
parts of the GPU.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
This was causing problems on a system with a large amount of RAM, where
display push buffers were being fetched incorrectly when placed in high
system memory addresses.
While this commit will resolve the issue on that particular system, the
issue will be avoided completely with another patch to more fully solve
problems with display and large amounts of system memory on Pascal.
It's still probably a good idea to disable this to prevent weird issues
in the future.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Depending on the kernel configuration, early ARM architecture setup code
may have attached the GPU to a DMA/IOMMU mapping that transparently uses
the IOMMU to back the DMA API. Tegra requires special handling for IOMMU
backed buffers (a special bit in the GPU's MMU page tables indicates the
memory path to take: via the SMMU or directly to the memory controller).
Transparently backing DMA memory with an IOMMU prevents Nouveau from
properly handling such memory accesses and causes memory access faults.
As a side-note: buffers other than those allocated in instance memory
don't need to be physically contiguous from the GPU's perspective since
the GPU can map them into contiguous buffers using its own MMU. Mapping
these buffers through the IOMMU is unnecessary and will even lead to
performance degradation because of the additional translation. One
exception to this are compressible buffers which need large pages. In
order to enable these large pages, multiple small pages will have to be
combined into one large (I/O virtually contiguous) mapping via the
IOMMU. However, that is a topic outside the scope of this fix and isn't
currently supported. An implementation will want to explicitly create
these large pages in the Nouveau driver, so detaching from a DMA/IOMMU
mapping would still be required.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Nicolas Chauvet <kwizart@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
In the quest to remove all stack VLA usage from the kernel[1], this
allocates the working buffers before starting the writing so it won't
abort in the middle. This needs an initial walk of the lists to figure
out how large the buffer should be.
[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
This patch unifies the naming of DRM functions for reference counting
of struct drm_device. The resulting code is more aligned with the rest
of the Linux kernel interfaces.
Signed-off-by: Thomas Zimmermann <tdz@users.sourceforge.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
This patch unifies the naming of DRM functions for reference counting
of struct drm_gem_object. The resulting code is more aligned with the
rest of the Linux kernel interfaces.
Signed-off-by: Thomas Zimmermann <tdz@users.sourceforge.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
This patch unifies the naming of DRM functions for reference counting
of struct drm_framebuffer. The resulting code is more aligned with the
rest of the Linux kernel interfaces.
Signed-off-by: Thomas Zimmermann <tdz@users.sourceforge.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Similar to commit 0bf8bf50ed ("module: Remove
const attribute from alias for MODULE_DEVICE_TABLE")
Fixes many -Wduplicate-decl-specifier warnings due to the combination of
const typeof() of already const variables.
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Smatch complains that "value" can be uninitialized when kstrtol()
returns -ERANGE.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Noticed this as I was skimming through, if we fail to allocate memory
for cli we'll end up returning without dropping the runtime PM ref we
got. Additionally, we'll even return the wrong return code! (ret most
likely will == 0 here, we want -ENOMEM).
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Fixes various reclocking related issues on prime systems.
Signed-off-by: Karol Herbst <karolherbst@gmail.com>
Signed-off-by: Martin Peres <martin.peres@free.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
If the entry size is too small, default to invalid values for both
boost_id and tdp_id, so as to default to the base clock in both cases.
Signed-off-by: Karol Herbst <karolherbst@gmail.com>
Signed-off-by: Martin Peres <martin.peres@free.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
With instantaneous high precision vblank timestamping
that updates at leading edge of vblank, the emulated
"hw vblank counter" from vblank timestamping, which
increments at leading edge of vblank, and reliable
page flip execution and completion at leading edge of
vblank, we should meet the requirements for fast/
immediate vblank irq disable/enable.
This is only allowed on nv50+ gpu's, ie. the ones with
atomic modesetting. One requirement for immediate vblank
disable is that high precision vblank timestamping works
reliably all the time on all connectors. This is not the
case on all pre-nv50 parts for analog VGA outputs, where we
currently don't always have support for scanout position
queries and therefore fall back to vblank interrupt
timestamping. The implementation in nv04_head_state() does
not return valid values for vblanks, vtotal, hblanks, htotal
for VGA outputs on all cards, but those are needed for scanout
position queries.
Testing on Linux-4.12-rc5 + drm-next on a GeForce 9500 GT
(NV G96) with timing measurement equipment indicates this
works fine, so allow immediate vblank disable for power
saving.
For debugging in case of unexpected trouble, booting
with kernel cmdline option drm.vblankoffdelay=0
(or echo 0 > /sys/module/drm/parameters/vblankoffdelay)
would keep vblank irqs permanently on to approximate old
behavior.
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Use drm_*_get() and drm_*_put() helpers instead of drm_*_reference() and
drm_*_unreference() helpers.
Generated by: scripts/coccinelle/api/drm-get-put.cocci
Fixes: 30ed49b55b ("drm/nouveau/kms/nv50-: move code underneath dispnv50/")
Signed-off-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Change values to u32, there's no need for them to be 64-bit.
Reported-by: Colin Ian King <colin.king@canonical.com>
Suggested-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
This allows to have the related MODULE_FIRMWARE tag only
on relevant arch (arm64).
This will saves about 400k on initramfs when not relevant
Signed-off-by: Nicolas Chauvet <kwizart@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Currently nouveau doesn't actually expose the state debugfs file that's
usually provided for any modesetting driver that supports atomic, even
if nouveau is loaded with atomic=1. This is due to the fact that the
standard debugfs files that DRM creates for atomic drivers is called
when drm_get_pci_dev() is called from nouveau_drm.c. This happens well
before we've initialized the display core, which is currently
responsible for setting the DRIVER_ATOMIC cap.
So, move the atomic option into nouveau_drm.c and just add the
DRIVER_ATOMIC cap whenever it's enabled on the kernel commandline. This
shouldn't cause any actual issues, as the atomic ioctl will still fail
as expected even if the display core doesn't disable it until later in
the init sequence. This also provides the added benefit of being able to
use the state debugfs file to check the current display state even if
clients aren't allowed to modify it through anything other than the
legacy ioctls.
Additionally, disable the DRIVER_ATOMIC cap in nv04's display core, as
this was already disabled there previously.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
This both uses the legacy modesetting structures in a racy manner, and
additionally also doesn't even check the right variable (enabled != the
CRTC is actually turned on for atomic).
This fixes issues on my P50 regarding the dedicated GPU not entering
runtime suspend.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: stable@vger.kernel.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
A CRTC being enabled doesn't mean it's on! It doesn't even necessarily
mean it's being used. This fixes runtime PM leaks on the P50 I've got
next to me.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
When MST and atomic were introduced to nouveau, another structure that
could contain a drm_connector embedded within it was introduced; struct
nv50_mstc. This meant that we no longer would be able to simply loop
through our connector list and assume that nouveau_connector() would
return a proper pointer for each connector, since the assertion that
all connectors coming from nouveau have a full nouveau_connector struct
became invalid.
Unfortunately, none of the actual code that looped through connectors
ever got updated, which means that we've been causing invalid memory
accesses for quite a while now.
An example that was caught by KASAN:
[ 201.038698] ==================================================================
[ 201.038792] BUG: KASAN: slab-out-of-bounds in nvif_notify_get+0x190/0x1a0 [nouveau]
[ 201.038797] Read of size 4 at addr ffff88076738c650 by task kworker/0:3/718
[ 201.038800]
[ 201.038822] CPU: 0 PID: 718 Comm: kworker/0:3 Tainted: G O 4.18.0-rc4Lyude-Test+ #1
[ 201.038825] Hardware name: LENOVO 20EQS64N0B/20EQS64N0B, BIOS N1EET78W (1.51 ) 05/18/2018
[ 201.038882] Workqueue: events nouveau_display_hpd_work [nouveau]
[ 201.038887] Call Trace:
[ 201.038894] dump_stack+0xa4/0xfd
[ 201.038900] print_address_description+0x71/0x239
[ 201.038929] ? nvif_notify_get+0x190/0x1a0 [nouveau]
[ 201.038935] kasan_report.cold.6+0x242/0x2fe
[ 201.038942] __asan_report_load4_noabort+0x19/0x20
[ 201.038970] nvif_notify_get+0x190/0x1a0 [nouveau]
[ 201.038998] ? nvif_notify_put+0x1f0/0x1f0 [nouveau]
[ 201.039003] ? kmsg_dump_rewind_nolock+0xe4/0xe4
[ 201.039049] nouveau_display_init.cold.12+0x34/0x39 [nouveau]
[ 201.039089] ? nouveau_user_framebuffer_create+0x120/0x120 [nouveau]
[ 201.039133] nouveau_display_resume+0x5c0/0x810 [nouveau]
[ 201.039173] ? nvkm_client_ioctl+0x20/0x20 [nouveau]
[ 201.039215] nouveau_do_resume+0x19f/0x570 [nouveau]
[ 201.039256] nouveau_pmops_runtime_resume+0xd8/0x2a0 [nouveau]
[ 201.039264] pci_pm_runtime_resume+0x130/0x250
[ 201.039269] ? pci_restore_standard_config+0x70/0x70
[ 201.039275] __rpm_callback+0x1f2/0x5d0
[ 201.039279] ? rpm_resume+0x560/0x18a0
[ 201.039283] ? pci_restore_standard_config+0x70/0x70
[ 201.039287] ? pci_restore_standard_config+0x70/0x70
[ 201.039291] ? pci_restore_standard_config+0x70/0x70
[ 201.039296] rpm_callback+0x175/0x210
[ 201.039300] ? pci_restore_standard_config+0x70/0x70
[ 201.039305] rpm_resume+0xcc3/0x18a0
[ 201.039312] ? rpm_callback+0x210/0x210
[ 201.039317] ? __pm_runtime_resume+0x9e/0x100
[ 201.039322] ? kasan_check_write+0x14/0x20
[ 201.039326] ? do_raw_spin_lock+0xc2/0x1c0
[ 201.039333] __pm_runtime_resume+0xac/0x100
[ 201.039374] nouveau_display_hpd_work+0x67/0x1f0 [nouveau]
[ 201.039380] process_one_work+0x7a0/0x14d0
[ 201.039388] ? cancel_delayed_work_sync+0x20/0x20
[ 201.039392] ? lock_acquire+0x113/0x310
[ 201.039398] ? kasan_check_write+0x14/0x20
[ 201.039402] ? do_raw_spin_lock+0xc2/0x1c0
[ 201.039409] worker_thread+0x86/0xb50
[ 201.039418] kthread+0x2e9/0x3a0
[ 201.039422] ? process_one_work+0x14d0/0x14d0
[ 201.039426] ? kthread_create_worker_on_cpu+0xc0/0xc0
[ 201.039431] ret_from_fork+0x3a/0x50
[ 201.039441]
[ 201.039444] Allocated by task 79:
[ 201.039449] save_stack+0x43/0xd0
[ 201.039452] kasan_kmalloc+0xc4/0xe0
[ 201.039456] kmem_cache_alloc_trace+0x10a/0x260
[ 201.039494] nv50_mstm_add_connector+0x9a/0x340 [nouveau]
[ 201.039504] drm_dp_add_port+0xff5/0x1fc0 [drm_kms_helper]
[ 201.039511] drm_dp_send_link_address+0x4a7/0x740 [drm_kms_helper]
[ 201.039518] drm_dp_check_and_send_link_address+0x1a7/0x210 [drm_kms_helper]
[ 201.039525] drm_dp_mst_link_probe_work+0x71/0xb0 [drm_kms_helper]
[ 201.039529] process_one_work+0x7a0/0x14d0
[ 201.039533] worker_thread+0x86/0xb50
[ 201.039537] kthread+0x2e9/0x3a0
[ 201.039541] ret_from_fork+0x3a/0x50
[ 201.039543]
[ 201.039546] Freed by task 0:
[ 201.039549] (stack is not available)
[ 201.039551]
[ 201.039555] The buggy address belongs to the object at ffff88076738c1a8
which belongs to the cache kmalloc-2048 of size 2048
[ 201.039559] The buggy address is located 1192 bytes inside of
2048-byte region [ffff88076738c1a8, ffff88076738c9a8)
[ 201.039563] The buggy address belongs to the page:
[ 201.039567] page:ffffea001d9ce200 count:1 mapcount:0 mapping:ffff88084000d0c0 index:0x0 compound_mapcount: 0
[ 201.039573] flags: 0x8000000000008100(slab|head)
[ 201.039578] raw: 8000000000008100 ffffea001da3be08 ffffea001da25a08 ffff88084000d0c0
[ 201.039582] raw: 0000000000000000 00000000000d000d 00000001ffffffff 0000000000000000
[ 201.039585] page dumped because: kasan: bad access detected
[ 201.039588]
[ 201.039591] Memory state around the buggy address:
[ 201.039594] ffff88076738c500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 201.039598] ffff88076738c580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 201.039601] >ffff88076738c600: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
[ 201.039604] ^
[ 201.039607] ffff88076738c680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 201.039611] ffff88076738c700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 201.039613] ==================================================================
Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: stable@vger.kernel.org
Cc: Karol Herbst <karolherbst@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Every codepath in nouveau that loops through the connector list
currently does so using the old method, which is prone to race
conditions from MST connectors being created and destroyed. This has
been causing a multitude of problems, including memory corruption from
trying to access connectors that have already been freed!
Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: stable@vger.kernel.org
Cc: Karol Herbst <karolherbst@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
The bo array has req->nr_buffers elements so the > should be >= so we
don't read beyond the end of the array.
Fixes: a1606a9596 ("drm/nouveau: new gem pushbuf interface, bump to 0.0.16")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
It was possible for this to be skipped when shutting down MST streams, and
leaving the core channel interlocked with a wndw channel update that never
happens - leading to a hung display.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Tested-By: Lyude Paul <lyude@redhat.com>
Since there's very few callers of these I've decided to do them all in
one patch. With this the unecessarily long drm_mode_connector_ prefix
is gone from the codebase! The only exception being struct
drm_mode_connector_set_property, which is part of the uapi so can't be
renamed.
Again done with sed+some manual fixups for indent issues.
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180709084016.23750-8-daniel.vetter@ffwll.ch
Use drm_connector_for_each_possible_encoder() for iterating
connector->encoder_ids[]. A bit more convenient not having
to deal with the implementation details.
v2: Replace drm_for_each_connector_encoder_ids() with
drm_connector_for_each_possible_encoder() (Daniel)
v3: Initialize nv_encoder to NULL to shut up gcc/smatch
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: nouveau@lists.freedesktop.org
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180702152927.13351-1-ville.syrjala@linux.intel.com
Ctxdmas for cursors from all heads are setup in the core channel, and due
to us tracking allocated handles per-window, we were failing with -EEXIST
on multiple-head setups trying to allocate duplicate handles.
The cursor code is hardcoded to use the core channel vram ctxdma already,
so just skip ctxdma allocation for cursor fbs to fix the issue.
Fixes: 5bca1621c0 ("drm/nouveau/kms/nv50-: move fb ctxdma tracking into windows")
Reported-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
