/* * Copyright 2016 Intel Corp. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. */ #ifndef _DRM_IRQ_H_ #define _DRM_IRQ_H_ #include /** * struct drm_pending_vblank_event - pending vblank event tracking */ struct drm_pending_vblank_event { /** * @base: Base structure for tracking pending DRM events. */ struct drm_pending_event base; /** * @pipe: drm_crtc_index() of the &drm_crtc this event is for. */ unsigned int pipe; /** * @event: Actual event which will be sent to userspace. */ struct drm_event_vblank event; }; /** * struct drm_vblank_crtc - vblank tracking for a CRTC * * This structure tracks the vblank state for one CRTC. * * Note that for historical reasons - the vblank handling code is still shared * with legacy/non-kms drivers - this is a free-standing structure not directly * connected to struct &drm_crtc. But all public interface functions are taking * a struct &drm_crtc to hide this implementation detail. */ struct drm_vblank_crtc { /** * @dev: Pointer to the &drm_device. */ struct drm_device *dev; /** * @queue: Wait queue for vblank waiters. */ wait_queue_head_t queue; /**< VBLANK wait queue */ /** * @disable_timer: Disable timer for the delayed vblank disabling * hysteresis logic. Vblank disabling is controlled through the * drm_vblank_offdelay module option and the setting of the * max_vblank_count value in the &drm_device structure. */ struct timer_list disable_timer; /** * @seqlock: Protect vblank count and time. */ seqlock_t seqlock; /* protects vblank count and time */ /** * @count: Current software vblank counter. */ u32 count; /** * @time: Vblank timestamp corresponding to @count. */ struct timeval time; /** * @refcount: Number of users/waiters of the vblank interrupt. Only when * this refcount reaches 0 can the hardware interrupt be disabled using * @disable_timer. */ atomic_t refcount; /* number of users of vblank interruptsper crtc */ /** * @last: Protected by dev->vbl_lock, used for wraparound handling. */ u32 last; /** * @inmodeset: Tracks whether the vblank is disabled due to a modeset. * For legacy driver bit 2 additionally tracks whether an additional * temporary vblank reference has been acquired to paper over the * hardware counter resetting/jumping. KMS drivers should instead just * call drm_crtc_vblank_off() and drm_crtc_vblank_on(), which explicitly * save and restore the vblank count. */ unsigned int inmodeset; /* Display driver is setting mode */ /** * @pipe: drm_crtc_index() of the &drm_crtc corresponding to this * structure. */ unsigned int pipe; /** * @framedur_ns: Frame/Field duration in ns, used by * drm_calc_vbltimestamp_from_scanoutpos() and computed by * drm_calc_timestamping_constants(). */ int framedur_ns; /** * @linedur_ns: Line duration in ns, used by * drm_calc_vbltimestamp_from_scanoutpos() and computed by * drm_calc_timestamping_constants(). */ int linedur_ns; /** * @enabled: Tracks the enabling state of the corresponding &drm_crtc to * avoid double-disabling and hence corrupting saved state. Needed by * drivers not using atomic KMS, since those might go through their CRTC * disabling functions multiple times. */ bool enabled; }; int drm_irq_install(struct drm_device *dev, int irq); int drm_irq_uninstall(struct drm_device *dev); int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs); u32 drm_crtc_vblank_count(struct drm_crtc *crtc); u32 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc, struct timeval *vblanktime); void drm_crtc_send_vblank_event(struct drm_crtc *crtc, struct drm_pending_vblank_event *e); void drm_crtc_arm_vblank_event(struct drm_crtc *crtc, struct drm_pending_vblank_event *e); bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe); bool drm_crtc_handle_vblank(struct drm_crtc *crtc); int drm_crtc_vblank_get(struct drm_crtc *crtc); void drm_crtc_vblank_put(struct drm_crtc *crtc); void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe); void drm_crtc_wait_one_vblank(struct drm_crtc *crtc); void drm_crtc_vblank_off(struct drm_crtc *crtc); void drm_crtc_vblank_reset(struct drm_crtc *crtc); void drm_crtc_vblank_on(struct drm_crtc *crtc); void drm_vblank_cleanup(struct drm_device *dev); u32 drm_accurate_vblank_count(struct drm_crtc *crtc); u32 drm_vblank_no_hw_counter(struct drm_device *dev, unsigned int pipe); int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, unsigned int pipe, int *max_error, struct timeval *vblank_time, unsigned flags, const struct drm_display_mode *mode); void drm_calc_timestamping_constants(struct drm_crtc *crtc, const struct drm_display_mode *mode); /** * drm_crtc_vblank_waitqueue - get vblank waitqueue for the CRTC * @crtc: which CRTC's vblank waitqueue to retrieve * * This function returns a pointer to the vblank waitqueue for the CRTC. * Drivers can use this to implement vblank waits using wait_event() and related * functions. */ static inline wait_queue_head_t *drm_crtc_vblank_waitqueue(struct drm_crtc *crtc) { return &crtc->dev->vblank[drm_crtc_index(crtc)].queue; } #endif >
drm/i915: Check for NULL i915_vma in intel_unpin_fb_obj()
I've seen this trigger twice now, where the i915_gem_object_to_ggtt() call in intel_unpin_fb_obj() returns NULL, resulting in an oops immediately afterwards as the (inlined) call to i915_vma_unpin_fence() tries to dereference it. It seems to be some race condition where the object is going away at shutdown time, since both times happened when shutting down the X server. The call chains were different: - VT ioctl(KDSETMODE, KD_TEXT): intel_cleanup_plane_fb+0x5b/0xa0 [i915] drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper] intel_atomic_commit_tail+0x749/0xfe0 [i915] intel_atomic_commit+0x3cb/0x4f0 [i915] drm_atomic_commit+0x4b/0x50 [drm] restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper] drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper] drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper] intel_fbdev_set_par+0x18/0x70 [i915] fb_set_var+0x236/0x460 fbcon_blank+0x30f/0x350 do_unblank_screen+0xd2/0x1a0 vt_ioctl+0x507/0x12a0 tty_ioctl+0x355/0xc30 do_vfs_ioctl+0xa3/0x5e0 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x13/0x94 - i915 unpin_work workqueue: intel_unpin_work_fn+0x58/0x140 [i915] process_one_work+0x1f1/0x480 worker_thread+0x48/0x4d0 kthread+0x101/0x140 and this patch purely papers over the issue by adding a NULL pointer check and a WARN_ON_ONCE() to avoid the oops that would then generally make the machine unresponsive. Other callers of i915_gem_object_to_ggtt() seem to also check for the returned pointer being NULL and warn about it, so this clearly has happened before in other places. [ Reported it originally to the i915 developers on Jan 8, applying the ugly workaround on my own now after triggering the problem for the second time with no feedback. This is likely to be the same bug reported as https://bugs.freedesktop.org/show_bug.cgi?id=98829 https://bugs.freedesktop.org/show_bug.cgi?id=99134 which has a patch for the underlying problem, but it hasn't gotten to me, so I'm applying the workaround. ] Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Imre Deak <imre.deak@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'tools/virtio/uapi')