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| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2016-06-21 10:54:12 +0200 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2016-06-21 21:43:24 +0200 |
| commit | 95c081c17f284de50eaca60d4d55643a64d39019 (patch) | |
| tree | c67aa3d3c9008fc1b91d26b58fc9d57f1f820aab /drivers/gpu/drm/drm_lock.c | |
| parent | drm: sti: rework init sequence (diff) | |
| download | linux-95c081c17f284de50eaca60d4d55643a64d39019.tar.xz linux-95c081c17f284de50eaca60d4d55643a64d39019.zip | |
drm: Move master pointer from drm_minor to drm_device
There can only be one current master, and it's for the overall device.
Render/control minors don't support master-based auth at all.
This simplifies the master logic a lot, at least in my eyes: All these
additional pointer chases are just confusing.
While doing the conversion I spotted some locking fail:
- drm_lock/drm_auth check dev->master without holding the
master_mutex. This is fallout from
commit c996fd0b956450563454e7ccc97a82ca31f9d043
Author: Thomas Hellstrom <thellstrom@vmware.com>
Date: Tue Feb 25 19:57:44 2014 +0100
drm: Protect the master management with a drm_device::master_mutex v3
but I honestly don't care one bit about those old legacy drivers
using this.
- debugfs name info should just grab master_mutex.
- And the fbdev helper looked at it to figure out whether someone is
using KMS. We just need a consistent value, so READ_ONCE. Aside: We
should probably check if anyone has opened a control node too, but I
guess current userspace doesn't really do that yet.
v2: Balance locking, reported by Julia.
v3: Rebase on top of Chris' oops fixes.
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v2)
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com> (v2)
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1466499262-18717-1-git-send-email-daniel.vetter@ffwll.ch
Diffstat (limited to 'drivers/gpu/drm/drm_lock.c')
| -rw-r--r-- | drivers/gpu/drm/drm_lock.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/gpu/drm/drm_lock.c b/drivers/gpu/drm/drm_lock.c index 0fb8f9e73486..ae0a4d39deec 100644 --- a/drivers/gpu/drm/drm_lock.c +++ b/drivers/gpu/drm/drm_lock.c @@ -334,7 +334,7 @@ void drm_legacy_lock_release(struct drm_device *dev, struct file *filp) struct drm_file *file_priv = filp->private_data; /* if the master has gone away we can't do anything with the lock */ - if (!file_priv->minor->master) + if (!dev->master) return; if (drm_legacy_i_have_hw_lock(dev, file_priv)) { |