diff options
| author | Björn Töpel <bjorn.topel@intel.com> | 2018-08-10 12:28:02 +0300 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2018-08-10 17:06:48 +0300 |
| commit | eb91e4d4db06adef06e7f50c02813c13c6ca5a5b (patch) | |
| tree | f721fe92f603de042c70d5ffee725c226488873e | |
| parent | a736e074680745faa5dc6be8dd3c58ad4850aab9 (diff) | |
| download | linux-eb91e4d4db06adef06e7f50c02813c13c6ca5a5b.tar.xz | |
Revert "xdp: add NULL pointer check in __xdp_return()"
This reverts commit 36e0f12bbfd3016f495904b35e41c5711707509f.
The reverted commit adds a WARN to check against NULL entries in the
mem_id_ht rhashtable. Any kernel path implementing the XDP (generic or
driver) fast path is required to make a paired
xdp_rxq_info_reg/xdp_rxq_info_unreg call for proper function. In
addition, a driver using a different allocation scheme than the
default MEM_TYPE_PAGE_SHARED is required to additionally call
xdp_rxq_info_reg_mem_model.
For MEM_TYPE_ZERO_COPY, an xdp_rxq_info_reg_mem_model call ensures
that the mem_id_ht rhashtable has a properly inserted allocator id. If
not, this would be a driver bug. A NULL pointer kernel OOPS is
preferred to the WARN.
Suggested-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| -rw-r--r-- | net/core/xdp.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/net/core/xdp.c b/net/core/xdp.c index c013b836006b..57285383ed00 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -348,8 +348,7 @@ static void __xdp_return(void *data, struct xdp_mem_info *mem, bool napi_direct, rcu_read_lock(); /* mem->id is valid, checked in xdp_rxq_info_reg_mem_model() */ xa = rhashtable_lookup(mem_id_ht, &mem->id, mem_id_rht_params); - if (!WARN_ON_ONCE(!xa)) - xa->zc_alloc->free(xa->zc_alloc, handle); + xa->zc_alloc->free(xa->zc_alloc, handle); rcu_read_unlock(); default: /* Not possible, checked in xdp_rxq_info_reg_mem_model() */ |