/* * Thunderbolt Cactus Ridge driver - NHI driver * * Copyright (c) 2014 Andreas Noever */ #ifndef DSL3510_H_ #define DSL3510_H_ #include #include /** * struct tb_nhi - thunderbolt native host interface */ struct tb_nhi { struct mutex lock; /* * Must be held during ring creation/destruction. * Is acquired by interrupt_work when dispatching * interrupts to individual rings. **/ struct pci_dev *pdev; void __iomem *iobase; struct tb_ring **tx_rings; struct tb_ring **rx_rings; struct work_struct interrupt_work; u32 hop_count; /* Number of rings (end point hops) supported by NHI. */ }; /** * struct tb_ring - thunderbolt TX or RX ring associated with a NHI */ struct tb_ring { struct mutex lock; /* must be acquired after nhi->lock */ struct tb_nhi *nhi; int size; int hop; int head; /* write next descriptor here */ int tail; /* complete next descriptor here */ struct ring_desc *descriptors; dma_addr_t descriptors_dma; struct list_head queue; struct list_head in_flight; struct work_struct work; bool is_tx:1; /* rx otherwise */ bool running:1; }; struct ring_frame; typedef void (*ring_cb)(struct tb_ring*, struct ring_frame*, bool canceled); /** * struct ring_frame - for use with ring_rx/ring_tx */ struct ring_frame { dma_addr_t buffer_phy; ring_cb callback; struct list_head list; u32 size:12; /* TX: in, RX: out*/ u32 flags:12; /* RX: out */ u32 eof:4; /* TX:in, RX: out */ u32 sof:4; /* TX:in, RX: out */ }; #define TB_FRAME_SIZE 0x100 /* minimum size for ring_rx */ struct tb_ring *ring_alloc_tx(struct tb_nhi *nhi, int hop, int size); struct tb_ring *ring_alloc_rx(struct tb_nhi *nhi, int hop, int size); void ring_start(struct tb_ring *ring); void ring_stop(struct tb_ring *ring); void ring_free(struct tb_ring *ring); int __ring_enqueue(struct tb_ring *ring, struct ring_frame *frame); /** * ring_rx() - enqueue a frame on an RX ring * * frame->buffer, frame->buffer_phy and frame->callback have to be set. The * buffer must contain at least TB_FRAME_SIZE bytes. * * frame->callback will be invoked with frame->size, frame->flags, frame->eof, * frame->sof set once the frame has been received. * * If ring_stop is called after the packet has been enqueued frame->callback * will be called with canceled set to true. * * Return: Returns ESHUTDOWN if ring_stop has been called. Zero otherwise. */ static inline int ring_rx(struct tb_ring *ring, struct ring_frame *frame) { WARN_ON(ring->is_tx); return __ring_enqueue(ring, frame); } /** * ring_tx() - enqueue a frame on an TX ring * * frame->buffer, frame->buffer_phy, frame->callback, frame->size, frame->eof * and frame->sof have to be set. * * frame->callback will be invoked with once the frame has been transmitted. * * If ring_stop is called after the packet has been enqueued frame->callback * will be called with canceled set to true. * * Return: Returns ESHUTDOWN if ring_stop has been called. Zero otherwise. */ static inline int ring_tx(struct tb_ring *ring, struct ring_frame *frame) { WARN_ON(!ring->is_tx); return __ring_enqueue(ring, frame); } #endif 6e77f6dfba96c543e55b6672d5a37e'>cpupower/utils/helpers/misc.c
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authorLinus Torvalds <torvalds@linux-foundation.org>2017-01-29 13:50:06 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-01-29 13:50:06 -0800
commit39cb2c9a316e77f6dfba96c543e55b6672d5a37e (patch)
tree98fe974ee4e20121253de7f61fc8d01bdb3821c1 /tools/power/cpupower/utils/helpers/misc.c
parent2c5d9555d6d937966d79d4c6529a5f7b9206e405 (diff)
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/power/cpupower/utils/helpers/misc.c')