During system suspend after connector switch off its dpms field
is set to connector previous dpms state. To properly resume dpms field
should be set to its actual state (off) before resuming to previous dpms state.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Before DPMS off driver disables vblank.
It should be balanced by vblank enable after DPMS on.
The patch fixes issue with page_flip ioctl not being able
to acquire vblank counter introduced by patch:
drm: Always reject drm_vblank_get() after drm_vblank_off()
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
HPD events can be generated by components even if drm_dev is not fully
initialized, to skip such events kms poll initialization should
be performed at the end of load callback followed directly by forced
connection detection.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
In case of error during plane initialization load callback
incorrectly return success, this patch fixes it.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
All KMS objects are destroyed by drm_mode_config_cleanup in proper order
so component drivers should not care about it.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Initialization of vblank with MAX_CRTC caused attempts
to disabling vblanks for non-existing crtcs in case
drm used fewer crtcs. The patch fixes it.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
When screen objects are enabled, the bpp is assumed to be 32, otherwise
it is set to 16.
v2:
* Use u32 instead of u64 for assumed_bpp.
* Fixed mechanism to check for screen objects
* Limit the back buffer size to VRAM.
Signed-off-by: Sinclair Yeh <syeh@vmware.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Cc: <stable@vger.kernel.org>
The hash key computation in vmw_cmdbuf_res_remove incorrectly didn't take
the resource type into account, contrary to all the other related functions.
This becomes important when the cmdbuf resource manager handles more than
one resource type.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
After:
commit d059f652e7
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
AuthorDate: Fri Jul 25 18:07:40 2014 +0200
drm: Handle legacy per-crtc locking with full acquire ctx
drm_mode_cursor_common() was switched to use drm_modeset_(un)lock_crtc()
which uses full aquire ctx. So dropping/reaquiring the lock via
drm_modeset_(un)lock() directly isn't the right thing to do, as lockdep
kindly points out.
The 'FIXME's about sorting out whether vmwgfx *really* needs to lock-all
for cursor updates still apply.
Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Tested-by: Thomas Hellstrom <thellstrom@vmware.com>
- dpm stability fixes for SI and KV
- remove an invalid pci id
- kmalloc_array fixes
- minor cleanups
* 'drm-fixes-3.18' of git://people.freedesktop.org/~agd5f/linux:
drm/radeon: remove some buggy dead code
drm/radeon: remove invalid pci id
drm/radeon: dpm fixes for asrock systems
radeon: clean up coding style differences in radeon_get_bios()
drm/radeon: Use drm_malloc_ab instead of kmalloc_array
drm/radeon/dpm: disable ulv support on SI
bunch of DP fixes, and some backlight fix.
* tag 'drm-intel-fixes-2014-10-30' of git://anongit.freedesktop.org/drm-intel:
drm/i915/dp: only use training pattern 3 on platforms that support it
drm/i915: Ignore VBT backlight check on Macbook 2, 1
drm/i915: Fix GMBUSFREQ on vlv/chv
drm/i915: Ignore long hpds on eDP ports
drm/i915: Do a dummy DPCD read before the actual read
Ivybridge + 30" monitor prints a drm error on every modeset, since IVB
doesn't support DP3 we should even bother trying to use it.
This regression has been introduced in
commit 06ea66b6bb
Author: Todd Previte <tprevite@gmail.com>
Date: Mon Jan 20 10:19:39 2014 -0700
drm/i915: Enable 5.4Ghz (HBR2) link rate for Displayport 1.2-capable
devices
Reported-by: Dave Airlie <airlied@redhat.com>
Reference: http://mid.gmane.org/1414566170-9868-1-git-send-email-airlied@gmail.com
Cc: Todd Previte <tprevite@gmail.com>
Cc: stable@vger.kernel.org (3.15+)
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
The calculation of "num_shader_engines" has a precedence bug because
the right shift happens before the mask, but this variable is never used
so we can just delete it.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
commit c675949ec5
Author: Jani Nikula <jani.nikula@intel.com>
Date: Wed Apr 9 11:31:37 2014 +0300
drm/i915: do not setup backlight if not available according to VBT
prevents backlight setup on Macbook 2,1. Apply quirk to ignore the VBT
check so backlight is set up properly.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=81438
Signed-off-by: Jens Stein Jørgensen <jens.s.stein@gmail.com>
Cc: stable@vger.kernel.org (3.15+)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Should avoid kmalloc failures due to large number of array entries.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=81991
Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Three changes for the Armada DRM driver:
1. Add back the flags which tell the DRM core that we can do vblank. This
was removed in error during the recent restructuring, and came to light
while trying textured Xv rendering.
2. Fixing a refcount leak with Xv overlay.
3. As per recent discussion, the drm_vblank_pre_modeset() calls can cause
deadlock with other changes to generic code. This change prevents those
deadlocks by switching to the drm_crtc_vblank_*() calls instead.
* 'drm-armada-fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
drm/armada: convert to use vblank_on/off calls
drm/armada: fix page_flip refcounting leak
drm/armada: add IRQ support back
vlv_cdclk_freq is in kHz but we need MHz for the GMBUSFREQ divider.
This is a regression from:
commit f8bf63fdcb
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date: Fri Jun 13 13:37:54 2014 +0300
drm/i915: Kill duplicated cdclk readout code from i2c
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Turning vdd on/off can generate a long hpd pulse on eDP ports. In order
to handle hpd we would need to turn on vdd to perform aux transfers.
This would lead to an endless cycle of
"vdd off -> long hpd -> vdd on -> detect -> vdd off -> ..."
So ignore long hpd pulses on eDP ports. eDP panels should be physically
tied to the machine anyway so they should not actually disappear and
thus don't need long hpd handling. Short hpds are still needed for link
re-train and whatnot so we can't just turn off the hpd interrupt
entirely for eDP ports. Perhaps we could turn it off whenever the panel
is disabled, but just ignoring the long hpd seems sufficient.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Todd Previte <tprevite@gmail.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Sometimes we seem to get utter garbage from DPCD reads. The resulting
buffer is filled with the same byte, and the operation completed without
errors. My HP ZR24w monitor seems particularly susceptible to this
problem once it's gone into a sleep mode.
The issue seems to happen only for the first AUX message that wakes the
sink up. But as the first AUX read we often do is the DPCD receiver
cap it does wreak a bit of havoc with subsequent link training etc. when
the receiver cap bw/lane/etc. information is garbage.
A sufficient workaround seems to be to perform a single byte dummy read
before reading the actual data. I suppose that just wakes up the sink
sufficiently and we can just throw away the returned data in case it's
crap. DP_DPCD_REV seems like a sufficiently safe location to read here.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Todd Previte <tprevite@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
qemu as used by xend/xm toolstack uses a different subvendor id.
Bind the drm driver also to this emulated card.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
Limit primary to qemu vgamem size, to avoid reaching
qemu guest bug "requested primary larger than framebuffer"
on resizing screen too large to fit.
Remove unneeded and misleading variables.
Related to:
https://bugzilla.redhat.com/show_bug.cgi?id=1127552
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
two nouveau fixes.
* 'linux-3.18' of git://anongit.freedesktop.org/git/nouveau/linux-2.6:
drm/nouveau: fix regression on agp boards
drm/gt215/gr: fix initialisation on gddr5 boards
Extends the fix in f2f9a2cbaf to also
workaround permission issues noticed by people using AGP systems.
Cc: stable@vger.kernel.org # 3.16: f2f9a2c: drm/nouveau: fix regression
Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
The binary driver modifies the default context to have this value, rather
than 0x3d0040, *after* it's filled the buffer with the usual golden data.
We don't really have anything in place to locate the correct offset to do
these type of modifications outside of the generation function, so this
will have to do.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
first set of i915 fixes, all over.
* tag 'drm-intel-next-fixes-2014-10-17' of git://anongit.freedesktop.org/drm-intel:
drm/i915: fix short vs. long hpd detection
drm/i915: Don't trust the DP_DETECT bit for eDP ports on CHV
drm/i915: properly reenable gen8 pipe IRQs
drm/i915: Move DIV_ROUND_CLOSEST_ULL macro to header
drm/i915: intel_backlight scale() math WA
First round of fixes for 3.18.
- Use gart for DMA ring tests to avoid caching issues with HDP
- SI dpm stability fixes
- Performance stabilization fixes
- misc other things
* 'drm-fixes-3.18' of git://people.freedesktop.org/~agd5f/linux:
drm/radeon: reduce sparse false positive warnings
drm/radeon: fix vm page table block size calculation
drm/ttm: Don't evict BOs outside of the requested placement range
drm/ttm: Don't skip fpfn check if lpfn is 0 in ttm_bo_mem_compat
drm/radeon: use gart memory for DMA ring tests
drm/radeon: fix speaker allocation setup
drm/radeon: initialize sadb to NULL in the audio code
Revert "drm/radeon/dpm: drop clk/voltage dependency filters for SI"
Revert "drm/radeon: drop btc_get_max_clock_from_voltage_dependency_table"
A future commit changes the way various vblank calls behave, which
causes drivers to break. Converting to use the drm_crtc_vblank_on/off
calls avoids this breakage.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
A refcounting leak was found of the original frame buffer attached to
the CRTC when using the page_flip ioctl, resulting in the frame buffer
never being freed.
This was not obvious initially, as if the page flip subsequently
re-attaches the original frame buffer, the refcounts will be balanced.
However, if the original frame buffer is freed, then it will be leaked.
Fix this by ensuring that we take a reference on the incoming fb, but
rely on the queued work to drop that ref count.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
include radeon_asic.h header file in the various xxx_dpm.c files
to reduce sparse false positive warnings. Not so great patch
in itself, but reducing warning count from 391 to 258 may help
to see real problems..
Signed-off-by: Michele Curti <michele.curti@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
The page offset is 12 bits. For example if we have an
8 GB VM, we'd need 33 bits. The number of bits needed
for PD + PT is 21 (33 - 12 or log2(8) + 18), not 20
(log2(8) + 17).
Noticed by Alexey during code review.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
The radeon driver uses placement range restrictions for several reasons,
in particular to make sure BOs in VRAM can be accessed by the CPU, e.g.
during a page fault.
Without this change, TTM could evict other BOs while trying to satisfy
the requested placement, even if the evicted BOs were outside of the
requested placement range. Doing so didn't free up any space in the
requested placement range, so the (potentially high) eviction cost was
incurred for no benefit.
Nominating for stable because radeon driver changes in 3.17 made this
much more noticeable than before.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=84662
Cc: stable@vger.kernel.org
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Avoids HDP cache flush issues when using vram which can
cause ring test failures on certain boards.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Alexander Fyodorov <halcy@yandex.ru>
Cc: stable@vger.kernel.org
If the sad_count is 0, set the hw to stereo and change
the error message to a warn. A lot of monitors don't
set the speaker allocation block.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Fix short vs. long hpd detection for non-g4x and non-pch split
platforms.
Broken since introduction in
commit 13cf550448
Author: Dave Airlie <airlied@redhat.com>
Date: Wed Jun 18 11:29:35 2014 +1000
drm/i915: rework digital port IRQ handling (v2)
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=83175
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
On CHV the display DDC pins may be muxed to an alternate function if
there's no need for DDC on a specific port, which is the case for eDP
ports since there's no way to plug in a DP++ HDMI dongle.
This causes problems when trying to determine if the port is present
since the the DP_DETECTED bit is the latched state of the DDC SDA pin
at boot. If the DDC pins are muxed to an alternate function the bit
may indicate that the port isn't present.
To work around this look at the VBT as well as the DP_DETECTED bit
to determine if we should attempt registering an eDP port. Do this
only for ports B and C since port D doesn't support eDP (no PPS/BLC).
In theory someone could also wire up a normal DP port w/o DDC lines.
That would just mean that simple DP++ HDMI dongles wouldn't work
on such a port. With this change we would still fail to register
such DP ports. But let's hope no one wires their board in such a way,
and if they do we can extend the VBT checks to cover normal DP ports
as well.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=84265
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Pull drm updates from Dave Airlie:
"This is the main git pull for the drm,
I pretty much froze major pulls at -rc5/6 time, and haven't had much
fallout, so will probably continue doing that.
Lots of changes all over, big internal header cleanup to make it clear
drm features are legacy things and what are things that modern KMS
drivers should be using. Also big move to use the new generic fences
in all the TTM drivers.
core:
atomic prep work,
vblank rework changes, allows immediate vblank disables
major header reworking and cleanups to better delinate legacy
interfaces from what KMS drivers should be using.
cursor planes locking fixes
ttm:
move to generic fences (affects all TTM drivers)
ppc64 caching fixes
radeon:
userptr support,
uvd for old asics,
reset rework for fence changes
better buffer placement changes,
dpm feature enablement
hdmi audio support fixes
intel:
Cherryview work,
180 degree rotation,
skylake prep work,
execlist command submission
full ppgtt prep work
cursor improvements
edid caching,
vdd handling improvements
nouveau:
fence reworking
kepler memory clock work
gt21x clock work
fan control improvements
hdmi infoframe fixes
DP audio
ast:
ppc64 fixes
caching fix
rcar:
rcar-du DT support
ipuv3:
prep work for capture support
msm:
LVDS support for mdp4, new panel, gpu refactoring
exynos:
exynos3250 SoC support, drop bad mmap interface,
mipi dsi changes, and component match support"
* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (640 commits)
drm/mst: rework payload table allocation to conform better.
drm/ast: Fix HW cursor image
drm/radeon/kv: add uvd/vce info to dpm debugfs output
drm/radeon/ci: add uvd/vce info to dpm debugfs output
drm/radeon: export reservation_object from dmabuf to ttm
drm/radeon: cope with foreign fences inside the reservation object
drm/radeon: cope with foreign fences inside display
drm/core: use helper to check driver features
drm/radeon/cik: write gfx ucode version to ucode addr reg
drm/radeon/si: print full CS when we hit a packet 0
drm/radeon: remove unecessary includes
drm/radeon/combios: declare legacy_connector_convert as static
drm/radeon/atombios: declare connector convert tables as static
drm/radeon: drop btc_get_max_clock_from_voltage_dependency_table
drm/radeon/dpm: drop clk/voltage dependency filters for BTC
drm/radeon/dpm: drop clk/voltage dependency filters for CI
drm/radeon/dpm: drop clk/voltage dependency filters for SI
drm/radeon/dpm: drop clk/voltage dependency filters for NI
drm/radeon: disable audio when we disable hdmi (v2)
drm/radeon: split audio enable between eg and r600 (v2)
...
Pull scheduler updates from Ingo Molnar:
"The main changes in this cycle were:
- Optimized support for Intel "Cluster-on-Die" (CoD) topologies (Dave
Hansen)
- Various sched/idle refinements for better idle handling (Nicolas
Pitre, Daniel Lezcano, Chuansheng Liu, Vincent Guittot)
- sched/numa updates and optimizations (Rik van Riel)
- sysbench speedup (Vincent Guittot)
- capacity calculation cleanups/refactoring (Vincent Guittot)
- Various cleanups to thread group iteration (Oleg Nesterov)
- Double-rq-lock removal optimization and various refactorings
(Kirill Tkhai)
- various sched/deadline fixes
... and lots of other changes"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
sched/dl: Use dl_bw_of() under rcu_read_lock_sched()
sched/fair: Delete resched_cpu() from idle_balance()
sched, time: Fix build error with 64 bit cputime_t on 32 bit systems
sched: Improve sysbench performance by fixing spurious active migration
sched/x86: Fix up typo in topology detection
x86, sched: Add new topology for multi-NUMA-node CPUs
sched/rt: Use resched_curr() in task_tick_rt()
sched: Use rq->rd in sched_setaffinity() under RCU read lock
sched: cleanup: Rename 'out_unlock' to 'out_free_new_mask'
sched: Use dl_bw_of() under RCU read lock
sched/fair: Remove duplicate code from can_migrate_task()
sched, mips, ia64: Remove __ARCH_WANT_UNLOCKED_CTXSW
sched: print_rq(): Don't use tasklist_lock
sched: normalize_rt_tasks(): Don't use _irqsave for tasklist_lock, use task_rq_lock()
sched: Fix the task-group check in tg_has_rt_tasks()
sched/fair: Leverage the idle state info when choosing the "idlest" cpu
sched: Let the scheduler see CPU idle states
sched/deadline: Fix inter- exclusive cpusets migrations
sched/deadline: Clear dl_entity params when setscheduling to different class
sched/numa: Kill the wrong/dead TASK_DEAD check in task_numa_fault()
...
Pull core locking updates from Ingo Molnar:
"The main updates in this cycle were:
- mutex MCS refactoring finishing touches: improve comments, refactor
and clean up code, reduce debug data structure footprint, etc.
- qrwlock finishing touches: remove old code, self-test updates.
- small rwsem optimization
- various smaller fixes/cleanups"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/lockdep: Revert qrwlock recusive stuff
locking/rwsem: Avoid double checking before try acquiring write lock
locking/rwsem: Move EXPORT_SYMBOL() lines to follow function definition
locking/rwlock, x86: Delete unused asm/rwlock.h and rwlock.S
locking/rwlock, x86: Clean up asm/spinlock*.h to remove old rwlock code
locking/semaphore: Resolve some shadow warnings
locking/selftest: Support queued rwlock
locking/lockdep: Restrict the use of recursive read_lock() with qrwlock
locking/spinlocks: Always evaluate the second argument of spin_lock_nested()
locking/Documentation: Update locking/mutex-design.txt disadvantages
locking/Documentation: Move locking related docs into Documentation/locking/
locking/mutexes: Use MUTEX_SPIN_ON_OWNER when appropriate
locking/mutexes: Refactor optimistic spinning code
locking/mcs: Remove obsolete comment
locking/mutexes: Document quick lock release when unlocking
locking/mutexes: Standardize arguments in lock/unlock slowpaths
locking: Remove deprecated smp_mb__() barriers
Pull vfs updates from Al Viro:
"The big thing in this pile is Eric's unmount-on-rmdir series; we
finally have everything we need for that. The final piece of prereqs
is delayed mntput() - now filesystem shutdown always happens on
shallow stack.
Other than that, we have several new primitives for iov_iter (Matt
Wilcox, culled from his XIP-related series) pushing the conversion to
->read_iter()/ ->write_iter() a bit more, a bunch of fs/dcache.c
cleanups and fixes (including the external name refcounting, which
gives consistent behaviour of d_move() wrt procfs symlinks for long
and short names alike) and assorted cleanups and fixes all over the
place.
This is just the first pile; there's a lot of stuff from various
people that ought to go in this window. Starting with
unionmount/overlayfs mess... ;-/"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (60 commits)
fs/file_table.c: Update alloc_file() comment
vfs: Deduplicate code shared by xattr system calls operating on paths
reiserfs: remove pointless forward declaration of struct nameidata
don't need that forward declaration of struct nameidata in dcache.h anymore
take dname_external() into fs/dcache.c
let path_init() failures treated the same way as subsequent link_path_walk()
fix misuses of f_count() in ppp and netlink
ncpfs: use list_for_each_entry() for d_subdirs walk
vfs: move getname() from callers to do_mount()
gfs2_atomic_open(): skip lookups on hashed dentry
[infiniband] remove pointless assignments
gadgetfs: saner API for gadgetfs_create_file()
f_fs: saner API for ffs_sb_create_file()
jfs: don't hash direct inode
[s390] remove pointless assignment of ->f_op in vmlogrdr ->open()
ecryptfs: ->f_op is never NULL
android: ->f_op is never NULL
nouveau: __iomem misannotations
missing annotation in fs/file.c
fs: namespace: suppress 'may be used uninitialized' warnings
...
The old code has problems with the Dell MST monitors due to some
assumptions I made that weren't true.
I initially thought the Virtual Channel Payload IDs had to be in
the DPCD table in ascending order, however it appears that assumption
is bogus.
The old code also assumed it was possible to insert a member
into the table and it would move other members up, like it does
when you remove table entries, however reality has shown this
isn't true.
So the new code allocates VCPIs separate from entries in the payload
tracking table, and when we remove an entry from the DPCD table,
I shuffle the tracking payload entries around in the struct.
This appears to make VT switch more robust (still not perfect)
with an MST enabled Dell monitor.
Signed-off-by: Dave Airlie <airlied@redhat.com>