6.15-stable review patch. If anyone has any objections, please let me know.
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From: Arunpravin Paneer Selvam Arunpravin.PaneerSelvam@amd.com
commit 95a16160ca1d75c66bf7a1c5e0bcaffb18e7c7fc upstream.
- 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 Signed-off-by: Christian König christian.koenig@amd.com Link: https://lore.kernel.org/r/20250716075125.240637-2-Arunpravin.PaneerSelvam@am... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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(+)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c @@ -5123,6 +5123,8 @@ exit: dev->dev->power.disable_depth--; #endif } + + amdgpu_vram_mgr_clear_reset_blocks(adev); adev->in_suspend = false;
if (adev->enable_mes) --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h @@ -154,6 +154,7 @@ int amdgpu_vram_mgr_reserve_range(struct 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); --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c @@ -783,6 +783,23 @@ uint64_t amdgpu_vram_mgr_vis_usage(struc }
/** + * 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 * * @man: TTM memory type manager --- 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 *bl 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 * * @mm: DRM buddy manager --- a/include/drm/drm_buddy.h +++ b/include/drm/drm_buddy.h @@ -160,6 +160,8 @@ int drm_buddy_block_trim(struct drm_budd 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,