This locking path needs proper auditing but probably too late for changes at this point for 2.6.36, so lets go with the quick fix, which is to drop the lock around schedule.
Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This is done by
1) Wake up lock waiters when we close the master file descriptor.
Not when the master structure is removed, since the latter
requires the waiters themselves to release the refcount on the
master structure -> Deadlock.
2) Send a SIGTERM to all clients waiting for the lock.
Normally these clients will get a SIGPIPE when the X server dies,
but clients may also spin trying to grab the DRM lock, without
getting any sort of notification.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
That return code is for in-kernel use only.
Use EINTR instead.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
This is step one towards having multiple masters sharing a drm
device in order to get fast-user-switching to work.
It splits out the information associated with the drm master
into a separate kref counted structure, and allocates this when
a master opens the device node. It also allows the current master
to abdicate (say while VT switched), and a new master to take over
the hardware.
It moves the Intel and radeon drivers to using the sarea from
within the new master structures.
Signed-off-by: Dave Airlie <airlied@redhat.com>
It's not used in any other drivers, and doesn't look like it will be from
drm.git master.
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@linux.ie>
To synchronize clip lists with the X server, the DRM lock must be held while
looking at drawable clip lists. To synchronize with other ring access, the
ring mutex must be held while inserting commands into the ring. Failure to
do the first resulted in easy visual corruption when moving windows, and the
second could have corrupted the ring with DRI2.
Grabbing the DRM lock involves using the DRM tasklet mechanism, grabbing the
ring mutex means potentially sleeping. Deal with both of these by always
running the tasklet from a work handler.
Also, protect from clip list changes since the vblank request was queued by
making sure the window has at least one rectangle while looking inside,
preventing oopses .
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
There is a problem with debugging the X server and gdb crashes in
the xkb startup code.
This avoids the problem by allowing the master process to get signals.
It should be safe as the signal blocker is mainly so that you can
Ctrl-Z a 3D application without locking up the whole box. Ctrl-Z the
X server isn't something many people do.
Signed-off-by: Dave Airlie <airlied@redhat.com>
If a specific tasklet shares data with irq context,
it needs to take a private irq-blocking spinlock within
the tasklet itself.
Signed-off-by: Dave Airlie <airlied@redhat.com>
With the coming of kernel based modesetting and the memory manager stuff,
the everything in one directory approach was getting very ugly and
starting to be unmanageable.
This restructures the drm along the lines of other kernel components.
It creates a drivers/gpu/drm directory and moves the hw drivers into
subdirectores. It moves the includes into an include/drm, and
sets up the unifdef for the userspace headers we should be exporting.
Signed-off-by: Dave Airlie <airlied@redhat.com>