Re: [PATCH] drm/amdgpu: use dirty framebuffer helper

[root <arthur.marsh@internode.on.net>]

Hi, I recently experienced lock-ups that only responded to magic sysreq 
reboots when the amdgpu module was loading on my pc (Athlon II X4 640 CPU,
with Radeon R7 250 - Cape Verde).

.config has:

CONFIG_DRM_AMDGPU=m
CONFIG_DRM_AMDGPU_SI=y
# CONFIG_DRM_AMDGPU_CIK is not set
# CONFIG_DRM_AMDGPU_USERPTR is not set

kernel command line has:

amdgpu.audio=1 amdgpu.si_support=1 radeon.si_support=0 page_owner=on \
amdgpu.gpu_recovery=1

Bisecting lead to:

commit 66f99628eb24409cb8feb5061f78283c8b65f820
Author: Hamza Mahfooz <hamza.mahfooz@amd.com>
Date:   Tue Sep 6 15:01:49 2022 -0400

    drm/amdgpu: use dirty framebuffer helper
    
    Currently, we aren't handling DRM_IOCTL_MODE_DIRTYFB. So, use
    drm_atomic_helper_dirtyfb() as the dirty callback in the amdgpu_fb_funcs
    struct.
    
    Signed-off-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
    Acked-by: Alex Deucher <alexander.deucher@amd.com>
    Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
index c20922a5af9f..5b09c8f4fe95 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
@@ -38,6 +38,7 @@
 #include <linux/pci.h>
 #include <linux/pm_runtime.h>
 #include <drm/drm_crtc_helper.h>
+#include <drm/drm_damage_helper.h>
 #include <drm/drm_edid.h>
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_fb_helper.h>
@@ -496,6 +497,7 @@ bool amdgpu_display_ddc_probe(struct amdgpu_connector *amdgpu_connector,
 static const struct drm_framebuffer_funcs amdgpu_fb_funcs = {
        .destroy = drm_gem_fb_destroy,
        .create_handle = drm_gem_fb_create_handle,
+       .dirty = drm_atomic_helper_dirtyfb,
 };
 
 uint32_t amdgpu_display_supported_domains(struct amdgpu_device *adev,

After doing a git bisect reset, git pull and reverting the patch above, I
rebuilt the kernel and am successfully running with the amdgpu module loaded
and using the Radeon R7 250 GPU.

I am happy to supply any further configuration details.

Arthur Marsh.