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	drm/crc-debugfs: User irqsafe spinlock in drm_crtc_add_crc_entry
We can be called from any context, we need to be prepared. Noticed this while hacking on vkms, which calls this function from a normal worker. Which really upsets lockdep. Cc: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com> Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com> Cc: Emil Velikov <emil.velikov@collabora.com> Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org> Reviewed-by: Benjamin Gaignard <benjamin.gaignard@linaro.org> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190605194556.16744-1-daniel.vetter@ffwll.ch
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					 1 changed files with 3 additions and 2 deletions
				
			
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			@ -396,8 +396,9 @@ int drm_crtc_add_crc_entry(struct drm_crtc *crtc, bool has_frame,
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	struct drm_crtc_crc *crc = &crtc->crc;
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	struct drm_crtc_crc_entry *entry;
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	int head, tail;
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	unsigned long flags;
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	spin_lock(&crc->lock);
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	spin_lock_irqsave(&crc->lock, flags);
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	/* Caller may not have noticed yet that userspace has stopped reading */
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	if (!crc->entries) {
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			@ -428,7 +429,7 @@ int drm_crtc_add_crc_entry(struct drm_crtc *crtc, bool has_frame,
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	head = (head + 1) & (DRM_CRC_ENTRIES_NR - 1);
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	crc->head = head;
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	spin_unlock(&crc->lock);
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	spin_unlock_irqrestore(&crc->lock, flags);
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	wake_up_interruptible(&crc->wq);
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