From 11fee7afbdcfab3830e393c4f871c146160c73ee Mon Sep 17 00:00:00 2001 From: Paulo Zanoni Date: Tue, 14 Oct 2014 18:11:35 -0300 Subject: [PATCH] drm/i915: call drm_vblank_cleanup() earlier at unload In its current place, it just segfaults while trying to access the CRTC structures: [ 9132.421681] Call Trace: [ 9132.421707] [] i915_get_crtc_scanoutpos+0x1e8/0x220 [i915] [ 9132.421727] [] drm_calc_vbltimestamp_from_scanoutpos+0x94/0x330 [drm] [ 9132.421744] [] ?vblank_disable_and_save+0x40/0x1e0 [drm] [ 9132.421769] [] i915_get_vblank_timestamp+0x68/0xb0 [i915] [ 9132.421786] [] drm_get_last_vbltimestamp+0x44/0x80 [drm] [ 9132.421801] [] vblank_disable_and_save+0x1a6/0x1e0 [drm] [ 9132.421817] [] drm_vblank_cleanup+0x61/0xa0 [drm] [ 9132.421849] [] i915_driver_unload+0xde/0x290 [i915] [ 9132.421867] [] drm_dev_unregister+0x24/0xb0 [drm] [ 9132.421884] [] drm_put_dev+0x1e/0x70 [drm] [ 9132.421901] [] i915_pci_remove+0x10/0x20 [i915] [ 9132.421910] [] pci_device_remove+0x36/0xb0 [ 9132.421920] [] __device_release_driver+0x7a/0xf0 [ 9132.421928] [] driver_detach+0xb8/0xc0 [ 9132.421936] [] bus_remove_driver+0x4a/0xb0 [ 9132.421944] [] driver_unregister+0x27/0x50 [ 9132.421953] [] pci_unregister_driver+0x25/0x70 [ 9132.421971] [] drm_pci_exit+0x78/0xa0 [drm] [ 9132.422000] [] i915_exit+0x20/0x94e [i915] [ 9132.422009] [] SyS_delete_module+0x13c/0x1f0 [ 9132.422019] [] ? trace_hardirqs_on_thunk+0x3a/0x3f [ 9132.422028] [] system_call_fastpath+0x16/0x1b This means it has to be before intel_modeset_cleanup, which cleans the CRTC structures. But if we move it to before intel_fbdev_fini(), we get WARNs because intel_fbdev_fini() still tries to use the vblanks, so the only acceptable point for drm_vblank_cleanup() seems to be this place. Related commit: commit cbb47d179fb345c579cd8cd884693903fceed26a Author: Chris Wilson Date: Mon Sep 23 17:33:20 2013 -0300 drm/i915: Add some missing steps to i915_driver_load error path Testsuite: igt/drv_module_reload Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=77511 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=83484 Cc: Chris Wilson Signed-off-by: Paulo Zanoni --- drivers/gpu/drm/i915/i915_dma.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c index 85d14e1..1b39807 100644 --- a/drivers/gpu/drm/i915/i915_dma.c +++ b/drivers/gpu/drm/i915/i915_dma.c @@ -1853,8 +1853,12 @@ int i915_driver_unload(struct drm_device *dev) acpi_video_unregister(); - if (drm_core_check_feature(dev, DRIVER_MODESET)) { + if (drm_core_check_feature(dev, DRIVER_MODESET)) intel_fbdev_fini(dev); + + drm_vblank_cleanup(dev); + + if (drm_core_check_feature(dev, DRIVER_MODESET)) { intel_modeset_cleanup(dev); /* @@ -1895,8 +1899,6 @@ int i915_driver_unload(struct drm_device *dev) i915_free_hws(dev); } - drm_vblank_cleanup(dev); - intel_teardown_gmbus(dev); intel_teardown_mchbar(dev); -- 2.1.1