github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-11-07 06:17:02 +01:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

8021q: publish vlan_devices_arrays entries with acquire/release

Browse Source 
Replace the smp_wmb()/smp_rmb() barrier pair with
smp_store_release()/smp_load_acquire() on
vg->vlan_devices_arrays[pidx][vidx].

vlan_group_prealloc_vid() publishes the array pointer via release;
__vlan_group_get_device() acquires it before accessing the array,
ensuring the allocated entries are visible.

Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Jinjie Ruan 2026-09-02 15:33:34 +08:00 committed by Jakub Kicinski
parent 2e9ff7bb66
commit d199b0d0bb
2 changed files with 5 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
net/8021q/vlan.c
View File

@ -70,10 +70,8 @@ static int vlan_group_prealloc_vid(struct vlan_group *vg,
if (array == NULL)
return -ENOBUFS;
/* paired with smp_rmb() in __vlan_group_get_device() */
smp_wmb();
vg->vlan_devices_arrays[pidx][vidx] = array;
/* paired with smp_load_acquire() in __vlan_group_get_device() */
smp_store_release(&vg->vlan_devices_arrays[pidx][vidx], array);
return 0;
}

8
net/8021q/vlan.h
View File

@ -56,11 +56,9 @@ static inline struct net_device *__vlan_group_get_device(struct vlan_group *vg,
{
struct net_device __rcu **array;
array = vg->vlan_devices_arrays[pidx]
[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
/* paired with smp_wmb() in vlan_group_prealloc_vid() */
smp_rmb();
/* Pairs with smp_store_release() in vlan_group_prealloc_vid() */
array = smp_load_acquire(&vg->vlan_devices_arrays[pidx]
[vlan_id / VLAN_GROUP_ARRAY_PART_LEN]);
return array ? rcu_dereference_raw(array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN]) : NULL;
}