When list_for_each_entry() completes the iteration over the whole list without breaking the loop, the iterator value will be a bogus pointer computed based on the head element. While it is safe to use the pointer to determine if it was computed based on the head element, either with list_entry_is_head() or &pos->member == head, using the iterator variable after the loop should be avoided. In preparation to limit the scope of a list iterator to the list traversal loop, use a dedicated pointer to point to the found element [1]. Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@xxxxxxxxxxxxxx/ [1] Signed-off-by: Jakob Koschel <jakobkoschel@xxxxxxxxx> --- drivers/infiniband/hw/hfi1/tid_rdma.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/infiniband/hw/hfi1/tid_rdma.c b/drivers/infiniband/hw/hfi1/tid_rdma.c index 2a7abf7a1f7f..b12abf83a91c 100644 --- a/drivers/infiniband/hw/hfi1/tid_rdma.c +++ b/drivers/infiniband/hw/hfi1/tid_rdma.c @@ -1239,7 +1239,7 @@ static int kern_alloc_tids(struct tid_rdma_flow *flow) struct hfi1_ctxtdata *rcd = flow->req->rcd; struct hfi1_devdata *dd = rcd->dd; u32 ngroups, pageidx = 0; - struct tid_group *group = NULL, *used; + struct tid_group *group = NULL, *used, *iter; u8 use; flow->tnode_cnt = 0; @@ -1248,13 +1248,15 @@ static int kern_alloc_tids(struct tid_rdma_flow *flow) goto used_list; /* First look at complete groups */ - list_for_each_entry(group, &rcd->tid_group_list.list, list) { - kern_add_tid_node(flow, rcd, "complete groups", group, - group->size); + list_for_each_entry(iter, &rcd->tid_group_list.list, list) { + kern_add_tid_node(flow, rcd, "complete groups", iter, + iter->size); - pageidx += group->size; - if (!--ngroups) + pageidx += iter->size; + if (!--ngroups) { + group = iter; break; + } } if (pageidx >= flow->npagesets) @@ -1277,7 +1279,7 @@ static int kern_alloc_tids(struct tid_rdma_flow *flow) * However, if we are at the head, we have reached the end of the * complete groups list from the first loop above */ - if (group && &group->list == &rcd->tid_group_list.list) + if (!group) goto bail_eagain; group = list_prepare_entry(group, &rcd->tid_group_list.list, list); base-commit: f82da161ea75dc4db21b2499e4b1facd36dab275 -- 2.25.1
