From c49b15b28c2aa9776c148208c2f76a4be5eb9934 Mon Sep 17 00:00:00 2001
From: Zhan Liu <zhan.liu@amd.com>
Date: Tue, 28 Jan 2020 16:38:53 -0500
Subject: drm/amd/display: Move drm_dp_mst_atomic_check() to the front of
Git-commit: ded58c7bbbf3b52c018db99fd4d530c3448a0c83
Patch-mainline: v5.6-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
dc_validate_global_state()
[Why]
Need to do atomic check first, then validate global state.
If not, when connecting both MST and HDMI displays and
set a bad mode via xrandr, system will hang.
[How]
Move drm_dp_mst_atomic_check() to the front of
dc_validate_global_state().
Signed-off-by: Zhan Liu <zhan.liu@amd.com>
Reviewed-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 2ac349849081..279541517a99 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -8167,6 +8167,16 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
goto fail;
#endif
+ /*
+ * Perform validation of MST topology in the state:
+ * We need to perform MST atomic check before calling
+ * dc_validate_global_state(), or there is a chance
+ * to get stuck in an infinite loop and hang eventually.
+ */
+ ret = drm_dp_mst_atomic_check(state);
+ if (ret)
+ goto fail;
+
if (dc_validate_global_state(dc, dm_state->context, false) != DC_OK) {
ret = -EINVAL;
goto fail;
@@ -8195,10 +8205,6 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
dc_retain_state(old_dm_state->context);
}
}
- /* Perform validation of MST topology in the state*/
- ret = drm_dp_mst_atomic_check(state);
- if (ret)
- goto fail;
/* Store the overall update type for use later in atomic check. */
for_each_new_crtc_in_state (state, crtc, new_crtc_state, i) {
--
2.28.0