user/sven/linux.git/drivers/gpu/drm/drm_lock.c, branch v4.11.3

sched/headers: Prepare for new header dependencies before moving code to

2017-03-02T07:42:29Z

We are going to split out of , which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder file that just maps to to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

drm: Avoid NULL dereference for DRM_LEGACY debug message

2016-11-28T07:39:41Z

smatch warns: drivers/gpu/drm/drm_lock.c:188 drm_legacy_lock() warn: variable dereferenced before check 'master->lock.hw_lock' (see line 177) Signed-off-by: Chris Wilson Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/20161127170910.29106-2-chris@chris-wilson.co.uk

drm: Used DRM_LEGACY for all legacy functions

2016-08-08T08:05:23Z

Except for nouveau, only legacy drivers need this really. And nouveau is already marked up with DRIVER_KMS_LEGACY_CONTEXT as the special case. I've tried to be careful to leave everything related to modeset still using the DRIVER_MODESET flag. Otherwise it's a direct replacement of !DRIVER_MODESET with DRIVER_LEGACY checks. Also helps readability since fewer negative checks overall. Reviewed-by: David Herrmann Reviewed-by: Frank Binns Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1470251470-30830-2-git-send-email-daniel.vetter@ffwll.ch

drm: Extract drm_is_current_master

2016-06-21T19:58:12Z

Just rolling out a bit of abstraction to be able to clean up the master logic in the next step. Cc: Chris Wilson Cc: Thomas Hellstrom Reviewed-by: Chris Wilson Reviewed-by: Emil Velikov Signed-off-by: Daniel Vetter

drm: Move master pointer from drm_minor to drm_device

2016-06-21T19:43:24Z

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 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 Cc: Chris Wilson Reviewed-by: Chris Wilson (v2) Reviewed-by: Emil Velikov (v2) Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1466499262-18717-1-git-send-email-daniel.vetter@ffwll.ch

drm: Hide hw.lock cleanup in filp->release better

2016-06-16T08:16:37Z

A few things: - Rename the cleanup function from drm_master_release to drm_legacy_lock_release. It doesn't relase any master stuff, but just the legacy hw lock. - Hide it in drm_lock.c, which allows us to make a few more functions static in there. To avoid forward decl we need to shuffle the code a bit though. - Push the check for ->master into the function itself. - Only call this for !DRIVER_MODESET. End result: Another place that takes struct_mutex gone for good for modern drivers. v2: Remove leftover comment. Reviewed-by: Chris Wilson Reviewed-by: Emil Velikov Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1465930269-7883-3-git-send-email-daniel.vetter@ffwll.ch

signals: kill block_all_signals() and unblock_all_signals()

2015-11-07T01:50:42Z

It is hardly possible to enumerate all problems with block_all_signals() and unblock_all_signals(). Just for example, 1. block_all_signals(SIGSTOP/etc) simply can't help if the caller is multithreaded. Another thread can dequeue the signal and force the group stop. 2. Even is the caller is single-threaded, it will "stop" anyway. It will not sleep, but it will spin in kernel space until SIGCONT or SIGKILL. And a lot more. In short, this interface doesn't work at all, at least the last 10+ years. Daniel said: Yeah the only times I played around with the DRM_LOCK stuff was when old drivers accidentally deadlocked - my impression is that the entire DRM_LOCK thing was never really tested properly ;-) Hence I'm all for purging where this leaks out of the drm subsystem. Signed-off-by: Oleg Nesterov Acked-by: Daniel Vetter Acked-by: Dave Airlie Cc: Richard Weinberger Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

drm: Reject DRI1 hw lock ioctl functions for kms drivers

2015-07-02T15:00:48Z

I've done some extensive history digging across libdrm, mesa and xf86-video-{intel,nouveau,ati}. The only potential user of this with kms drivers I could find was ttmtest, which once used drmGetLock still. But that mistake was quickly fixed up. Even the intel xvmc library (which otherwise was really good with using dri1 stuff in kms mode) managed to never take the hw lock for dri2 (and hence kms). Hence it should be save to unconditionally disallow this. Cc: Peter Antoine Reviewed-by: Peter Antoine Signed-off-by: Daniel Vetter

drm: unexport drm_global_mutex

2014-09-12T09:19:47Z

Drivers really, really have no business even looking at this lock. And thankfully they don't. So unexport it and move the declaration to drm_internal.h. Signed-off-by: Daniel Vetter

drm: move drm-lock API to drm_legacy.h

2014-09-10T07:43:34Z

Same as the other legacy APIs, most of this is internal, so prefix it with drm_legacy_* and move into drm_legacy.h. Signed-off-by: David Herrmann Reviewed-by: Thierry Reding Signed-off-by: Dave Airlie