media: atomisp: Fix premature setting of HMM_BO_DEVICE_INITED flag

The HMM_BO_DEVICE_INITED flag was being set in hmm_bo_device_init()
before key initialization steps like kmem_cache_create(),
kmem_cache_alloc(), and __bo_init().

This means that if any of these steps fail, the flag remains set,
misleading other parts of the driver (e.g. hmm_bo_alloc())
into thinking the device is initialized. This could lead
to undefined behavior or invalid memory use.

Additionally, since __bo_init() is called from inside
hmm_bo_device_init() after the flag was already set, its internal
check for HMM_BO_DEVICE_INITED is redundant.

- Move the flag assignment to the end after all allocations succeed.
- Remove redundant check of the flag inside __bo_init()

See the link [1] below for a backtrace which happens when deliberately
triggering the problem of the flag getting set too early.

Link: https://lore.kernel.org/linux-media/CAGn2d8ONZpOHXex8kjeUDgRPiMqKp8vZ=xhGbEDGphV1t7ZEFw@mail.gmail.com/ [1]
Signed-off-by: Abdelrahman Fekry <abdelrahmanfekry375@gmail.com>
Link: https://lore.kernel.org/r/20250628052536.43737-1-abdelrahmanfekry375@gmail.com
Reviewed-by: Hans de Goede <hansg@kernel.org>
Signed-off-by: Hans de Goede <hansg@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This commit is contained in:
Abdelrahman Fekry
2025-06-28 08:25:36 +03:00
committed by Mauro Carvalho Chehab
parent 5e2330ef08
commit bd290dddb0

View File

@@ -37,8 +37,6 @@ static int __bo_init(struct hmm_bo_device *bdev, struct hmm_buffer_object *bo,
unsigned int pgnr)
{
check_bodev_null_return(bdev, -EINVAL);
var_equal_return(hmm_bo_device_inited(bdev), 0, -EINVAL,
"hmm_bo_device not inited yet.\n");
/* prevent zero size buffer object */
if (pgnr == 0) {
dev_err(atomisp_dev, "0 size buffer is not allowed.\n");
@@ -341,7 +339,6 @@ int hmm_bo_device_init(struct hmm_bo_device *bdev,
spin_lock_init(&bdev->list_lock);
mutex_init(&bdev->rbtree_mutex);
bdev->flag = HMM_BO_DEVICE_INITED;
INIT_LIST_HEAD(&bdev->entire_bo_list);
bdev->allocated_rbtree = RB_ROOT;
@@ -376,6 +373,8 @@ int hmm_bo_device_init(struct hmm_bo_device *bdev,
__bo_insert_to_free_rbtree(&bdev->free_rbtree, bo);
bdev->flag = HMM_BO_DEVICE_INITED;
return 0;
}