From: Hou Tao <houtao1@xxxxxxxxxx>
bpf_selem_alloc() has two callers:
(1) bpf_sk_storage_clone_elem()
bpf_sk_storage_clone() has already disabled migration before invoking
bpf_sk_storage_clone_elem().
(2) bpf_local_storage_update()
Its callers include: cgrp/task/inode/sock storage ->map_update_elem()
callbacks and bpf_{cgrp|task|inode|sk}_storage_get() helpers. These
running contexts have already disabled migration
Therefore, there is no need to add extra migrate_{disable|enable} pair
in bpf_selem_alloc(). Also add a cant_migrate() check in
bpf_selem_alloc().
Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx>
---
kernel/bpf/bpf_local_storage.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c
index 12cf6382175e..fd48a2a17ccd 100644
--- a/kernel/bpf/bpf_local_storage.c
+++ b/kernel/bpf/bpf_local_storage.c
@@ -80,10 +80,10 @@ bpf_selem_alloc(struct bpf_local_storage_map *smap, void *owner,
if (charge_mem && mem_charge(smap, owner, smap->elem_size))
return NULL;
+ cant_migrate();
+
if (smap->bpf_ma) {
- migrate_disable();
selem = bpf_mem_cache_alloc_flags(&smap->selem_ma, gfp_flags);
- migrate_enable();
if (selem)
/* Keep the original bpf_map_kzalloc behavior
* before started using the bpf_mem_cache_alloc.
--
2.29.2
