6.6-stable review patch. If anyone has any objections, please let me know.
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From: Ville Syrjälä ville.syrjala@linux.intel.com
[ Upstream commit 582dc04b0658ef3b90aeb49cbdd9747c2f1eccc3 ]
Calling i915_gem_object_get_dma_address() from the vblank evade critical section triggers might_sleep().
While we know that we've already pinned the framebuffer and thus i915_gem_object_get_dma_address() will in fact not sleep in this case, it seems reasonable to keep the unconditional might_sleep() for maximum coverage.
So let's instead pre-populate the dma address during fb pinning, which all happens before we enter the vblank evade critical section.
We can use u32 for the dma address as this class of hardware doesn't support >32bit addresses.
Cc: stable@vger.kernel.org Fixes: 0225a90981c8 ("drm/i915: Make cursor plane registers unlocked") Reported-by: Borislav Petkov bp@alien8.de Closes: https://lore.kernel.org/intel-gfx/20240227100342.GAZd2zfmYcPS_SndtO@fat_crat... Signed-off-by: Ville Syrjälä ville.syrjala@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20240325175738.3440-1-ville.sy... Tested-by: Borislav Petkov (AMD) bp@alien8.de Reviewed-by: Chaitanya Kumar Borah chaitanya.kumar.borah@intel.com (cherry picked from commit c1289a5c3594cf04caa94ebf0edeb50c62009f1f) Signed-off-by: Rodrigo Vivi rodrigo.vivi@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/i915/display/intel_cursor.c | 4 +--- drivers/gpu/drm/i915/display/intel_display_types.h | 1 + drivers/gpu/drm/i915/display/intel_fb_pin.c | 10 ++++++++++ 3 files changed, 12 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_cursor.c b/drivers/gpu/drm/i915/display/intel_cursor.c index 0d21c34f74990..61df6cd3f3778 100644 --- a/drivers/gpu/drm/i915/display/intel_cursor.c +++ b/drivers/gpu/drm/i915/display/intel_cursor.c @@ -34,12 +34,10 @@ static u32 intel_cursor_base(const struct intel_plane_state *plane_state) { struct drm_i915_private *dev_priv = to_i915(plane_state->uapi.plane->dev); - const struct drm_framebuffer *fb = plane_state->hw.fb; - struct drm_i915_gem_object *obj = intel_fb_obj(fb); u32 base;
if (DISPLAY_INFO(dev_priv)->cursor_needs_physical) - base = i915_gem_object_get_dma_address(obj, 0); + base = plane_state->phys_dma_addr; else base = intel_plane_ggtt_offset(plane_state);
diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h index 7fc92b1474cc4..8b0dc2b75da4a 100644 --- a/drivers/gpu/drm/i915/display/intel_display_types.h +++ b/drivers/gpu/drm/i915/display/intel_display_types.h @@ -701,6 +701,7 @@ struct intel_plane_state { #define PLANE_HAS_FENCE BIT(0)
struct intel_fb_view view; + u32 phys_dma_addr; /* for cursor_needs_physical */
/* Plane pxp decryption state */ bool decrypt; diff --git a/drivers/gpu/drm/i915/display/intel_fb_pin.c b/drivers/gpu/drm/i915/display/intel_fb_pin.c index fffd568070d41..a131656757f2b 100644 --- a/drivers/gpu/drm/i915/display/intel_fb_pin.c +++ b/drivers/gpu/drm/i915/display/intel_fb_pin.c @@ -254,6 +254,16 @@ int intel_plane_pin_fb(struct intel_plane_state *plane_state) return PTR_ERR(vma);
plane_state->ggtt_vma = vma; + + /* + * Pre-populate the dma address before we enter the vblank + * evade critical section as i915_gem_object_get_dma_address() + * will trigger might_sleep() even if it won't actually sleep, + * which is the case when the fb has already been pinned. + */ + if (phys_cursor) + plane_state->phys_dma_addr = + i915_gem_object_get_dma_address(intel_fb_obj(fb), 0); } else { struct intel_framebuffer *intel_fb = to_intel_framebuffer(fb);