mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2025-03-08 21:16:29 +07:00
fc8fd40eb2
So I just wanted to add a new field to struct drm_device and accidentally stumbled over something. According to comments dev->open_count is protected by dev->count_lock, but that's totally not the case. It's protected by drm_global_mutex. Unfortunately the vga switcheroo callbacks took this comment at face value. The problem is that we can't just take the drm_global_mutex because: - It would lead to a locking inversion with the driver load/unload paths. - It wouldn't actually protect anything, for that we'd need to wrap the entire vga switcheroo code in the drm_global_mutex. And I'm not sure whether that would actually solve anything. What we probably want is a try_to_grab_switcheroo reference kind of thing which is used in the driver's ->open callback. Then we could move all that ->can_switch madness into the vga switcheroo core where it really belongs. But since that would amount to real work take the easy way out and just add a comment. It's definitely not going to make anything worse since doing switcheroo state changes while restarting X just isn't recommended. Even though the delayed switching code does exactly that. v2: - Simplify the ->can_switch implementations more (Thierry) - Fix comment about the dev->open_count locking (Thierry) Cc: Thierry Reding <treding@nvidia.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> (v1) Reviewed-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> |
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| .. | ||
| dvo_ch7xxx.c | ||
| dvo_ch7017.c | ||
| dvo_ivch.c | ||
| dvo_ns2501.c | ||
| dvo_sil164.c | ||
| dvo_tfp410.c | ||
| dvo.h | ||
| i915_cmd_parser.c | ||
| i915_debugfs.c | ||
| i915_dma.c | ||
| i915_drv.c | ||
| i915_drv.h | ||
| i915_gem_context.c | ||
| i915_gem_debug.c | ||
| i915_gem_dmabuf.c | ||
| i915_gem_evict.c | ||
| i915_gem_execbuffer.c | ||
| i915_gem_gtt.c | ||
| i915_gem_stolen.c | ||
| i915_gem_tiling.c | ||
| i915_gem.c | ||
| i915_gpu_error.c | ||
| i915_ioc32.c | ||
| i915_irq.c | ||
| i915_params.c | ||
| i915_reg.h | ||
| i915_suspend.c | ||
| i915_sysfs.c | ||
| i915_trace_points.c | ||
| i915_trace.h | ||
| i915_ums.c | ||
| intel_acpi.c | ||
| intel_bios.c | ||
| intel_bios.h | ||
| intel_crt.c | ||
| intel_ddi.c | ||
| intel_display.c | ||
| intel_dp.c | ||
| intel_drv.h | ||
| intel_dsi_cmd.c | ||
| intel_dsi_cmd.h | ||
| intel_dsi_pll.c | ||
| intel_dsi.c | ||
| intel_dsi.h | ||
| intel_dvo.c | ||
| intel_fbdev.c | ||
| intel_hdmi.c | ||
| intel_i2c.c | ||
| intel_lvds.c | ||
| intel_modes.c | ||
| intel_opregion.c | ||
| intel_overlay.c | ||
| intel_panel.c | ||
| intel_pm.c | ||
| intel_ringbuffer.c | ||
| intel_ringbuffer.h | ||
| intel_sdvo_regs.h | ||
| intel_sdvo.c | ||
| intel_sideband.c | ||
| intel_sprite.c | ||
| intel_tv.c | ||
| intel_uncore.c | ||
| Kconfig | ||
| Makefile | ||