drm/amd/powerplay: fix segment fault issue in multi-display case.

Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Junwei Zhang <Jerry.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cgs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cgs.c
index 7a4b101..75cb5b9 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cgs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cgs.c
@@ -816,10 +816,13 @@ static int amdgpu_cgs_get_active_displays_info(void *cgs_device,
        struct drm_device *ddev = adev->ddev;
        struct drm_crtc *crtc;
        uint32_t line_time_us, vblank_lines;
+       struct cgs_mode_info *mode_info;
 
        if (info == NULL)
                return -EINVAL;
 
+       mode_info = info->mode_info;
+
        if (adev->mode_info.num_crtc && adev->mode_info.mode_config_initialized) {
                list_for_each_entry(crtc,
                                &ddev->mode_config.crtc_list, head) {
@@ -828,7 +831,7 @@ static int amdgpu_cgs_get_active_displays_info(void *cgs_device,
                                info->active_display_mask |= (1 << amdgpu_crtc->crtc_id);
                                info->display_count++;
                        }
-                       if (info->mode_info != NULL &&
+                       if (mode_info != NULL &&
                                crtc->enabled && amdgpu_crtc->enabled &&
                                amdgpu_crtc->hw_mode.clock) {
                                line_time_us = (amdgpu_crtc->hw_mode.crtc_htotal * 1000) /
@@ -836,10 +839,10 @@ static int amdgpu_cgs_get_active_displays_info(void *cgs_device,
                                vblank_lines = amdgpu_crtc->hw_mode.crtc_vblank_end -
                                                        amdgpu_crtc->hw_mode.crtc_vdisplay +
                                                        (amdgpu_crtc->v_border * 2);
-                               info->mode_info->vblank_time_us = vblank_lines * line_time_us;
-                               info->mode_info->refresh_rate = drm_mode_vrefresh(&amdgpu_crtc->hw_mode);
-                               info->mode_info->ref_clock = adev->clock.spll.reference_freq;
-                               info->mode_info++;
+                               mode_info->vblank_time_us = vblank_lines * line_time_us;
+                               mode_info->refresh_rate = drm_mode_vrefresh(&amdgpu_crtc->hw_mode);
+                               mode_info->ref_clock = adev->clock.spll.reference_freq;
+                               mode_info = NULL;
                        }
                }
        }