[PATCH 6.19 270/781] drm/buddy: release free_trees array on buddy mm teardown

Greg Kroah-Hartman
2026-02-25T01:31:49Z

From: Michał Grzelak <michal.grzelak@intel.com>

[ Upstream commit 7d0507772406e129329983b8b807e5b499bd74fd ]

During initialization of DRM buddy memory manager at drm_buddy_init,
mm->free_trees array is allocated for both clear and dirty RB trees.
During cleanup happening at drm_buddy_fini it is never freed, leading to
following memory leaks observed on xe module load & unload cycles:

kmemleak_alloc+0x4a/0x90
__kmalloc_cache_noprof+0x488/0x800
drm_buddy_init+0xc2/0x330 [drm_buddy]
__xe_ttm_vram_mgr_init+0xc3/0x190 [xe]
xe_ttm_stolen_mgr_init+0xf5/0x9d0 [xe]
xe_device_probe+0x326/0x9e0 [xe]
xe_pci_probe+0x39a/0x610 [xe]
local_pci_probe+0x47/0xb0
pci_device_probe+0xf3/0x260
really_probe+0xf1/0x3c0
__driver_probe_device+0x8c/0x180
driver_probe_device+0x24/0xd0
__driver_attach+0x10f/0x220
bus_for_each_dev+0x7f/0xe0
driver_attach+0x1e/0x30
bus_add_driver+0x151/0x290

Deallocate array for free trees when cleaning up buddy memory manager
in the same way as if going through out_free_tree label.

Fixes: d4cd665c98c1 ("drm/buddy: Separate clear and dirty free block trees")
Signed-off-by: Michał Grzelak <michal.grzelak@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
Link: https://patch.msgid.link/20251208102714.4008260-2-michal.grzelak@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/drm_buddy.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/drm_buddy.c b/drivers/gpu/drm/drm_buddy.c
index 2f279b46bd2cf..8308116058cc1 100644
--- a/drivers/gpu/drm/drm_buddy.c
+++ b/drivers/gpu/drm/drm_buddy.c
@@ -420,6 +420,7 @@ void drm_buddy_fini(struct drm_buddy *mm)

for_each_free_tree(i)
kfree(mm->free_trees[i]);
+ kfree(mm->free_trees);
kfree(mm->roots);
}
EXPORT_SYMBOL(drm_buddy_fini);
--
2.51.0