Re: [PATCH v5 2/3] drm/amdgpu: Reset the clear flag in buddy during resume

[Arunpravin Paneer Selvam <arunpravin.paneerselvam@amd.com>]

On 7/16/2025 4:31 PM, Christian König wrote:
> On 16.07.25 12:47, Christian König wrote:
>> On 16.07.25 12:28, Arunpravin Paneer Selvam wrote:
>>> Hi Dave,
>>>
>>> I am trying to push this series into drm-misc-fixes, but I get the below error when dim push-branch drm-misc-fixes.
>>>
>>> dim:ERROR:e24c180b4300("drm/amdgpu:Reset the clear flag in buddy during resume"): Mandatory Maintainer Acked-by missing., aborting
>>>
>>> Looks like maintainers Acked-by is required to push the patches into drm-misc-fixes ?
>> Strange, it should work with my Acked-by. Let me give it a try.
> I successfully pushed the patch to drm-misc-fixes.
>
> No idea why that didn't worked for you. Maybe update your dim script Arun.

Thanks Christian, I will check the dim script.

Regards,

Arun.

>
> Regards,
> Christian.
>
>> Regards,
>> Christian.
>>
>>> Regards,
>>>
>>> Arun.
>>>
>>> On 7/16/2025 1:21 PM, Arunpravin Paneer Selvam wrote:
>>>> - Added a handler in DRM buddy manager to reset the cleared
>>>>     flag for the blocks in the freelist.
>>>>
>>>> - This is necessary because, upon resuming, the VRAM becomes
>>>>     cluttered with BIOS data, yet the VRAM backend manager
>>>>     believes that everything has been cleared.
>>>>
>>>> v2:
>>>>     - Add lock before accessing drm_buddy_clear_reset_blocks()(Matthew Auld)
>>>>     - Force merge the two dirty blocks.(Matthew Auld)
>>>>     - Add a new unit test case for this issue.(Matthew Auld)
>>>>     - Having this function being able to flip the state either way would be
>>>>       good. (Matthew Brost)
>>>>
>>>> v3(Matthew Auld):
>>>>     - Do merge step first to avoid the use of extra reset flag.
>>>>
>>>> Signed-off-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
>>>> Suggested-by: Christian König <christian.koenig@amd.com>
>>>> Acked-by: Christian König <christian.koenig@amd.com>
>>>> Reviewed-by: Matthew Auld <matthew.auld@intel.com>
>>>> Cc: stable@vger.kernel.org
>>>> Fixes: a68c7eaa7a8f ("drm/amdgpu: Enable clear page functionality")
>>>> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3812
>>>> ---
>>>>    drivers/gpu/drm/amd/amdgpu/amdgpu_device.c   |  2 +
>>>>    drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h      |  1 +
>>>>    drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 17 ++++++++
>>>>    drivers/gpu/drm/drm_buddy.c                  | 43 ++++++++++++++++++++
>>>>    include/drm/drm_buddy.h                      |  2 +
>>>>    5 files changed, 65 insertions(+)
>>>>
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>>> index 723ab95d8c48..ac92220f9fc3 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>>> @@ -5327,6 +5327,8 @@ int amdgpu_device_resume(struct drm_device *dev, bool notify_clients)
>>>>            dev->dev->power.disable_depth--;
>>>>    #endif
>>>>        }
>>>> +
>>>> +    amdgpu_vram_mgr_clear_reset_blocks(adev);
>>>>        adev->in_suspend = false;
>>>>          if (amdgpu_acpi_smart_shift_update(dev, AMDGPU_SS_DEV_D0))
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
>>>> index 215c198e4aff..2309df3f68a9 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
>>>> @@ -155,6 +155,7 @@ int amdgpu_vram_mgr_reserve_range(struct amdgpu_vram_mgr *mgr,
>>>>                      uint64_t start, uint64_t size);
>>>>    int amdgpu_vram_mgr_query_page_status(struct amdgpu_vram_mgr *mgr,
>>>>                          uint64_t start);
>>>> +void amdgpu_vram_mgr_clear_reset_blocks(struct amdgpu_device *adev);
>>>>      bool amdgpu_res_cpu_visible(struct amdgpu_device *adev,
>>>>                    struct ttm_resource *res);
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
>>>> index abdc52b0895a..07c936e90d8e 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
>>>> @@ -782,6 +782,23 @@ uint64_t amdgpu_vram_mgr_vis_usage(struct amdgpu_vram_mgr *mgr)
>>>>        return atomic64_read(&mgr->vis_usage);
>>>>    }
>>>>    +/**
>>>> + * amdgpu_vram_mgr_clear_reset_blocks - reset clear blocks
>>>> + *
>>>> + * @adev: amdgpu device pointer
>>>> + *
>>>> + * Reset the cleared drm buddy blocks.
>>>> + */
>>>> +void amdgpu_vram_mgr_clear_reset_blocks(struct amdgpu_device *adev)
>>>> +{
>>>> +    struct amdgpu_vram_mgr *mgr = &adev->mman.vram_mgr;
>>>> +    struct drm_buddy *mm = &mgr->mm;
>>>> +
>>>> +    mutex_lock(&mgr->lock);
>>>> +    drm_buddy_reset_clear(mm, false);
>>>> +    mutex_unlock(&mgr->lock);
>>>> +}
>>>> +
>>>>    /**
>>>>     * amdgpu_vram_mgr_intersects - test each drm buddy block for intersection
>>>>     *
>>>> diff --git a/drivers/gpu/drm/drm_buddy.c b/drivers/gpu/drm/drm_buddy.c
>>>> index a1e652b7631d..a94061f373de 100644
>>>> --- a/drivers/gpu/drm/drm_buddy.c
>>>> +++ b/drivers/gpu/drm/drm_buddy.c
>>>> @@ -405,6 +405,49 @@ drm_get_buddy(struct drm_buddy_block *block)
>>>>    }
>>>>    EXPORT_SYMBOL(drm_get_buddy);
>>>>    +/**
>>>> + * drm_buddy_reset_clear - reset blocks clear state
>>>> + *
>>>> + * @mm: DRM buddy manager
>>>> + * @is_clear: blocks clear state
>>>> + *
>>>> + * Reset the clear state based on @is_clear value for each block
>>>> + * in the freelist.
>>>> + */
>>>> +void drm_buddy_reset_clear(struct drm_buddy *mm, bool is_clear)
>>>> +{
>>>> +    u64 root_size, size, start;
>>>> +    unsigned int order;
>>>> +    int i;
>>>> +
>>>> +    size = mm->size;
>>>> +    for (i = 0; i < mm->n_roots; ++i) {
>>>> +        order = ilog2(size) - ilog2(mm->chunk_size);
>>>> +        start = drm_buddy_block_offset(mm->roots[i]);
>>>> +        __force_merge(mm, start, start + size, order);
>>>> +
>>>> +        root_size = mm->chunk_size << order;
>>>> +        size -= root_size;
>>>> +    }
>>>> +
>>>> +    for (i = 0; i <= mm->max_order; ++i) {
>>>> +        struct drm_buddy_block *block;
>>>> +
>>>> +        list_for_each_entry_reverse(block, &mm->free_list[i], link) {
>>>> +            if (is_clear != drm_buddy_block_is_clear(block)) {
>>>> +                if (is_clear) {
>>>> +                    mark_cleared(block);
>>>> +                    mm->clear_avail += drm_buddy_block_size(mm, block);
>>>> +                } else {
>>>> +                    clear_reset(block);
>>>> +                    mm->clear_avail -= drm_buddy_block_size(mm, block);
>>>> +                }
>>>> +            }
>>>> +        }
>>>> +    }
>>>> +}
>>>> +EXPORT_SYMBOL(drm_buddy_reset_clear);
>>>> +
>>>>    /**
>>>>     * drm_buddy_free_block - free a block
>>>>     *
>>>> diff --git a/include/drm/drm_buddy.h b/include/drm/drm_buddy.h
>>>> index 9689a7c5dd36..513837632b7d 100644
>>>> --- a/include/drm/drm_buddy.h
>>>> +++ b/include/drm/drm_buddy.h
>>>> @@ -160,6 +160,8 @@ int drm_buddy_block_trim(struct drm_buddy *mm,
>>>>                 u64 new_size,
>>>>                 struct list_head *blocks);
>>>>    +void drm_buddy_reset_clear(struct drm_buddy *mm, bool is_clear);
>>>> +
>>>>    void drm_buddy_free_block(struct drm_buddy *mm, struct drm_buddy_block *block);
>>>>      void drm_buddy_free_list(struct drm_buddy *mm,