* [PATCH 7.2 472/556] drm/amdgpu: Fix init ordering in amdgpu_vram_mgr_init()
[not found] <20260909134230.441546314@linuxfoundation.org>
@ 2026-09-09 13:42 ` Greg Kroah-Hartman
2026-09-09 13:43 ` [PATCH 7.2 500/556] drm/ttm: Drop tt->restore after successful restore Greg Kroah-Hartman
1 sibling, 0 replies; 2+ messages in thread
From: Greg Kroah-Hartman @ 2026-09-09 13:42 UTC (permalink / raw)
To: stable
Cc: Greg Kroah-Hartman, patches, Sashiko-bot, Friedrich Vock,
Maarten Lankhorst, Tejun Heo, Maxime Ripard, Christian König,
Alex Deucher, amd-gfx, dri-devel, Thomas Hellström,
Arunpravin Paneer Selvam, Maarten Lankhorst,
Thadeu Lima de Souza Cascardo
7.2-stable review patch. If anyone has any objections, please let me know.
------------------
From: Thomas Hellström <thomas.hellstrom@linux.intel.com>
commit e773798e14ac0aea54ca9676083b91f445e5bc59 upstream.
drmm_cgroup_register_region() is called before INIT_LIST_HEAD() and
gpu_buddy_init() in amdgpu_vram_mgr_init(). If it fails, the function
returns early and bypasses those initializations.
Since adev->mman.initialized is set to true before amdgpu_vram_mgr_init()
is called, a failure triggers amdgpu_ttm_fini(), which calls
amdgpu_vram_mgr_fini(), which then:
- Calls list_for_each_entry_safe() on reservations_pending and
reserved_pages, whose list_head::next pointers are zero-initialized
(NULL). The loop does not recognize them as empty and dereferences NULL.
- Calls gpu_buddy_fini(), which iterates free_trees[] unconditionally
via for_each_free_tree(). Since mm->free_trees is NULL
(never allocated), this dereferences NULL.
Both result in a kernel panic on the module load error path.
Fix by moving drmm_cgroup_register_region() to after the list and buddy
allocator are fully initialized, so the teardown path is safe to run.
Reported-by: Sashiko-bot <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260428073116.15687-1-thomas.hellstrom@linux.intel.com?part=4
Fixes: 2b624a2c1865 ("drm/ttm: Handle cgroup based eviction in TTM")
Cc: Friedrich Vock <friedrich.vock@gmx.de>
Cc: Maarten Lankhorst <dev@lankhorst.se>
Cc: Tejun Heo <tj@kernel.org>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: amd-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Cc: stable@vger.kernel.org # v6.14+
Assisted-by: GitHub_Copilot:claude-sonnet-4.6
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
Reviewed-By: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Tested-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Link: https://patch.msgid.link/20260725100036.2372-2-thomas.hellstrom@linux.intel.com
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Maarten Lankhorst <dev@lankhorst.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
@@ -918,9 +918,6 @@ int amdgpu_vram_mgr_init(struct amdgpu_d
struct ttm_resource_manager *man = &mgr->manager;
int err;
- man->cg = drmm_cgroup_register_region(adev_to_drm(adev), "vram", adev->gmc.real_vram_size);
- if (IS_ERR(man->cg))
- return PTR_ERR(man->cg);
ttm_resource_manager_init(man, &adev->mman.bdev,
adev->gmc.real_vram_size);
@@ -935,6 +932,10 @@ int amdgpu_vram_mgr_init(struct amdgpu_d
if (err)
return err;
+ man->cg = drmm_cgroup_register_region(adev_to_drm(adev), "vram", adev->gmc.real_vram_size);
+ if (IS_ERR(man->cg))
+ return PTR_ERR(man->cg);
+
ttm_set_driver_manager(&adev->mman.bdev, TTM_PL_VRAM, &mgr->manager);
ttm_resource_manager_set_used(man, true);
return 0;
^ permalink raw reply [flat|nested] 2+ messages in thread
* [PATCH 7.2 500/556] drm/ttm: Drop tt->restore after successful restore
[not found] <20260909134230.441546314@linuxfoundation.org>
2026-09-09 13:42 ` [PATCH 7.2 472/556] drm/amdgpu: Fix init ordering in amdgpu_vram_mgr_init() Greg Kroah-Hartman
@ 2026-09-09 13:43 ` Greg Kroah-Hartman
1 sibling, 0 replies; 2+ messages in thread
From: Greg Kroah-Hartman @ 2026-09-09 13:43 UTC (permalink / raw)
To: stable
Cc: Greg Kroah-Hartman, patches, Thomas Hellström,
Christian Koenig, Huang Rui, Matthew Auld, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Simona Vetter,
dri-devel, linux-kernel, Matthew Brost
7.2-stable review patch. If anyone has any objections, please let me know.
------------------
From: Matthew Brost <matthew.brost@intel.com>
commit 941ac10529b3be5965a88d432a161ab459672ba8 upstream.
ttm_pool_restore_and_alloc() can successfully complete the restore
process via ttm_pool_restore_commit(), but tt->restore is not dropped
afterward. As a result, subsequent backup/restore flows observe what
appears to be a completed restore, while in reality shmem handles are
still installed in tt->pages, leading to the stack trace below.
Fix this by freeing and dropping tt->restore in
ttm_pool_restore_and_alloc() upon successful completion of the restore.
20545 [ 309.784531] RIP: 0010:sg_alloc_append_table_from_pages+0x38c/0x490
20547 [ 309.809570] RSP: 0018:ffffc9000623b838 EFLAGS: 00010206
20548 [ 309.814827] RAX: 0000000000001000 RBX: ffff88816e42a160 RCX: 0000000000000000
20549 [ 309.821986] RDX: 0000000000002000 RSI: 0000000000000003 RDI: 0000000000001000
20550 [ 309.829147] RBP: ffff88816e42a168 R08: 0000000000000002 R09: 000000007ffff000
20551 [ 309.836310] R10: ffffc9000623b928 R11: 0000000000000000 R12: 000000007ffff000
20552 [ 309.843471] R13: ffff88815ba5a100 R14: 0000000000000000 R15: 0000000000000001
20553 [ 309.850634] FS: 00007f9ff305e700(0000) GS:ffff888276c94000(0000) knlGS:0000000000000000
20554 [ 309.858749] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
20555 [ 309.864519] CR2: 00007f9fca701000 CR3: 00000001565e2005 CR4: 0000000008f70ef0
20556 [ 309.871678] PKRU: 55555558
20557 [ 309.874403] Call Trace:
20558 [ 309.876866] <TASK>
20559 [ 309.878988] sg_alloc_table_from_pages_segment+0x60/0x100
20560 [ 309.884415] ? ttm_resource_manager_usage+0x36/0x60 [ttm]
20561 [ 309.889845] ? xe_tt_map_sg+0x7d/0xd0 [xe]
20562 [ 309.894045] xe_tt_map_sg+0x7d/0xd0 [xe]
20563 [ 309.898037] xe_bo_move+0x927/0xaa0 [xe]
20564 [ 309.902029] ttm_bo_handle_move_mem+0xba/0x170 [ttm]
20565 [ 309.907022] ttm_bo_validate+0xbe/0x190 [ttm]
20566 [ 309.911405] xe_bo_validate+0x9a/0x120 [xe]
20567 [ 309.915663] xe_gpuvm_validate+0xd9/0x140 [xe]
20568 [ 309.920206] drm_gpuvm_validate+0x2f0/0x5b0 [drm_gpuvm]
20569 [ 309.925459] ? drm_exec_lock_obj+0x63/0x210 [drm_exec]
20570 [ 309.930627] xe_vm_validate_rebind+0x46/0xb0 [xe]
20571 [ 309.935428] xe_exec_fn+0x20/0x40 [xe]
20572 [ 309.939249] drm_gpuvm_exec_lock+0x78/0xc0 [drm_gpuvm]
20573 [ 309.944410] xe_validation_exec_lock+0x5a/0xa0 [xe]
20574 [ 309.949385] xe_exec_ioctl+0x806/0xc30 [xe]
20575 [ 309.953639] ? ttwu_queue_wakelist+0xd9/0xf0
20576 [ 309.957935] ? __pfx_xe_exec_fn+0x10/0x10 [xe]
20577 [ 309.962449] ? __wake_up_common+0x73/0xa0
20578 [ 309.966482] ? __pfx_xe_exec_ioctl+0x10/0x10 [xe]
20579 [ 309.971263] drm_ioctl_kernel+0xa3/0x100
20580 [ 309.975209] drm_ioctl+0x213/0x440
20581 [ 309.978637] ? __pfx_xe_exec_ioctl+0x10/0x10 [xe]
20582 [ 309.983415] xe_drm_ioctl+0x67/0xd0 [xe]
20583 [ 309.987408] __x64_sys_ioctl+0x7f/0xd0
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@gmail.com>
Cc: Simona Vetter <simona@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org
Fixes: b63d715b8090 ("drm/ttm/pool, drm/ttm/tt: Provide a helper to shrink pages")
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patch.msgid.link/20260617015531.1164189-1-matthew.brost@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/ttm/ttm_pool.c | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)
--- a/drivers/gpu/drm/ttm/ttm_pool.c
+++ b/drivers/gpu/drm/ttm/ttm_pool.c
@@ -917,6 +917,7 @@ int ttm_pool_restore_and_alloc(struct tt
{
struct ttm_pool_tt_restore *restore = tt->restore;
struct ttm_pool_alloc_state alloc;
+ int ret;
if (WARN_ON(!ttm_tt_is_backed_up(tt)))
return -EINVAL;
@@ -940,14 +941,22 @@ int ttm_pool_restore_and_alloc(struct tt
} else {
alloc = restore->snapshot_alloc;
if (ttm_pool_restore_valid(restore)) {
- int ret = ttm_pool_restore_commit(restore, tt->backup,
- ctx, &alloc);
+ ret = ttm_pool_restore_commit(restore, tt->backup,
+ ctx, &alloc);
if (ret)
return ret;
}
- if (!alloc.remaining_pages)
+ if (!alloc.remaining_pages) {
+ ret = ttm_pool_apply_caching(&alloc);
+ if (ret)
+ return ret;
+
+ kfree(tt->restore);
+ tt->restore = NULL;
+
return 0;
+ }
}
return __ttm_pool_alloc(pool, tt, ctx, &alloc, restore);
^ permalink raw reply [flat|nested] 2+ messages in thread
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2026-09-09 13:42 ` [PATCH 7.2 472/556] drm/amdgpu: Fix init ordering in amdgpu_vram_mgr_init() Greg Kroah-Hartman
2026-09-09 13:43 ` [PATCH 7.2 500/556] drm/ttm: Drop tt->restore after successful restore Greg Kroah-Hartman
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