On 22 June 2015 at 14:02, Daniel Vetter <daniel.vetter@xxxxxxxx> wrote: > We should never nest these since in theory kms drivers should know > when a pipe is on/off and call the corresponding enable/disable > functions for the vblank helper code only once. But for historical > reasons (the shared-with-ums version of this code in modeset_pre/post > needed to be able to cope with silly userspace that lost track of > things) we still have this bit of "robustness" around. > > Enforce this with a WARN_ON, preparing to eventually rip out this > special handling. Hello, just wanted to mention that this warning triggered on tegra124 and that I find it a bit disruptive: WARNING: CPU: 0 PID: 52 at drivers/gpu/drm/drm_irq.c:1323 drm_vblank_on+0x10c/0x130() Modules linked in: CPU: 0 PID: 52 Comm: kworker/0:1 Not tainted 4.1.0-next-20150625ccu-00024-gd8cbda3 #2295 Hardware name: NVIDIA Tegra SoC (Flattened Device Tree) Workqueue: events output_poll_execute [<c021b12c>] (unwind_backtrace) from [<c0215388>] (show_stack+0x20/0x24) [<c0215388>] (show_stack) from [<c0a9637c>] (dump_stack+0x8c/0x9c) [<c0a9637c>] (dump_stack) from [<c0256b58>] (warn_slowpath_common+0x94/0xc4) [<c0256b58>] (warn_slowpath_common) from [<c0256c44>] (warn_slowpath_null+0x2c/0x34) [<c0256c44>] (warn_slowpath_null) from [<c0686d38>] (drm_vblank_on+0x10c/0x130) [<c0686d38>] (drm_vblank_on) from [<c0686d84>] (drm_crtc_vblank_on+0x28/0x2c) [<c0686d84>] (drm_crtc_vblank_on) from [<c06cd518>] (tegra_crtc_commit+0x18/0x1c) [<c06cd518>] (tegra_crtc_commit) from [<c067b014>] (drm_atomic_helper_commit_modeset_enables+0xa0/0x198) [<c067b014>] (drm_atomic_helper_commit_modeset_enables) from [<c06cb068>] (tegra_atomic_complete.isra.1+0x38/0x5c) [<c06cb068>] (tegra_atomic_complete.isra.1) from [<c06cb0f4>] (tegra_atomic_commit+0x68/0x98) [<c06cb0f4>] (tegra_atomic_commit) from [<c06a1690>] (drm_atomic_commit+0x54/0x74) [<c06a1690>] (drm_atomic_commit) from [<c067b6ec>] (drm_atomic_helper_set_config+0x1b4/0x414) [<c067b6ec>] (drm_atomic_helper_set_config) from [<c068f43c>] (drm_mode_set_config_internal+0x68/0xe4) [<c068f43c>] (drm_mode_set_config_internal) from [<c067d34c>] (restore_fbdev_mode+0xe8/0x108) [<c067d34c>] (restore_fbdev_mode) from [<c067f390>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x2c/0x68) [<c067f390>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c067f3f4>] (drm_fb_helper_set_par+0x28/0x44) [<c067f3f4>] (drm_fb_helper_set_par) from [<c067f328>] (drm_fb_helper_hotplug_event+0xcc/0x108) [<c067f328>] (drm_fb_helper_hotplug_event) from [<c06cce98>] (tegra_fb_output_poll_changed+0x28/0x2c) [<c06cce98>] (tegra_fb_output_poll_changed) from [<c0674228>] (drm_kms_helper_hotplug_event+0x34/0x38) [<c0674228>] (drm_kms_helper_hotplug_event) from [<c06743dc>] (output_poll_execute+0x158/0x198) [<c06743dc>] (output_poll_execute) from [<c026d830>] (process_one_work+0x154/0x48c) [<c026d830>] (process_one_work) from [<c026dbbc>] (worker_thread+0x54/0x568) [<c026dbbc>] (worker_thread) from [<c02739ec>] (kthread+0xec/0x104) [<c02739ec>] (kthread) from [<c0211228>] (ret_from_fork+0x14/0x2c) Regards, Tomeu > Cc: Yogesh Mohan Marimuthu <yogesh.mohan.marimuthu@xxxxxxxxx> > Cc: Gaurav K Singh <gaurav.k.singh@xxxxxxxxx> > Cc: Michel Dänzer <michel.daenzer@xxxxxxx> > Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx> > --- > drivers/gpu/drm/drm_irq.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c > index f9cc68fbd2a3..3819465abe22 100644 > --- a/drivers/gpu/drm/drm_irq.c > +++ b/drivers/gpu/drm/drm_irq.c > @@ -1219,6 +1219,8 @@ void drm_vblank_off(struct drm_device *dev, int crtc) > vblank_disable_and_save(dev, crtc); > wake_up(&vblank->queue); > > + WARN_ON(vblank->inmodeset); > + > /* > * Prevent subsequent drm_vblank_get() from re-enabling > * the vblank interrupt by bumping the refcount. > @@ -1318,6 +1320,8 @@ void drm_vblank_on(struct drm_device *dev, int crtc) > return; > > spin_lock_irqsave(&dev->vbl_lock, irqflags); > + WARN_ON(!vblank->inmodeset); > + > /* Drop our private "prevent drm_vblank_get" refcount */ > if (vblank->inmodeset) { > atomic_dec(&vblank->refcount); > -- > 2.1.4 > > _______________________________________________ > dri-devel mailing list > dri-devel@xxxxxxxxxxxxxxxxxxxxx > http://lists.freedesktop.org/mailman/listinfo/dri-devel _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel