1. 06 5月, 2016 2 次提交
  2. 05 5月, 2016 11 次提交
  3. 04 5月, 2016 26 次提交
  4. 03 5月, 2016 1 次提交
    • M
      drm/atomic: Add WARN_ON when state->acquire_ctx is not set. · 7f4eaa89
      Maarten Lankhorst 提交于
      When I was writing an atomic wrapper for rmfb, I ran into the
      following backtrace from lockdep:
      
      =============================================
      [ INFO: possible recursive locking detected ]
      4.5.0-patser+ #4696 Tainted: G     U
      ---------------------------------------------
      kworker/2:2/2608 is trying to acquire lock:
       (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffc00c9ddc>] drm_modeset_lock+0x7c/0x120 [drm]
      
      but task is already holding lock:
       (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffc00c98cd>] modeset_backoff+0x8d/0x220 [drm]
      
      other info that might help us debug this:
       Possible unsafe locking scenario:
      
             CPU0
             ----
        lock(crtc_ww_class_mutex);
        lock(crtc_ww_class_mutex);
      
       *** DEADLOCK ***
      
       May be due to missing lock nesting notation
      
      4 locks held by kworker/2:2/2608:
       #0:  ("events"){.+.+.+}, at: [<ffffffff810a5eea>] process_one_work+0x15a/0x6c0
       #1:  ((&arg.work)){+.+.+.}, at: [<ffffffff810a5eea>] process_one_work+0x15a/0x6c0
       #2:  (crtc_ww_class_acquire){+.+.+.}, at: [<ffffffffc004532a>] drm_atomic_helper_remove_fb+0x4a/0x1d0 [drm_kms_helper]
       #3:  (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffc00c98cd>] modeset_backoff+0x8d/0x220 [drm]
      
      While lockdep probably catches this bug when it happens, it's better
      to explicitly warn when state->acquire_ctx is not set.
      Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      Link: http://patchwork.freedesktop.org/patch/msgid/1462266751-29123-1-git-send-email-maarten.lankhorst@linux.intel.com
      7f4eaa89