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| author | Zhu Yanjun <yanjun.zhu@oracle.com> | 2019-06-06 04:00:03 -0400 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-06-06 10:32:16 -0700 |
| commit | 85cb928787eab6a2f4ca9d2a798b6f3bed53ced1 (patch) | |
| tree | ba00eee29d1ce0b1fa287a89a4f97a0828c5b0bc /net/rds | |
| parent | 8d037f92de5f34b44312c4df6c115c6df92d7085 (diff) | |
| download | lwn-85cb928787eab6a2f4ca9d2a798b6f3bed53ced1.tar.gz lwn-85cb928787eab6a2f4ca9d2a798b6f3bed53ced1.zip | |
net: rds: fix memory leak in rds_ib_flush_mr_pool
When the following tests last for several hours, the problem will occur.
Server:
rds-stress -r 1.1.1.16 -D 1M
Client:
rds-stress -r 1.1.1.14 -s 1.1.1.16 -D 1M -T 30
The following will occur.
"
Starting up....
tsks tx/s rx/s tx+rx K/s mbi K/s mbo K/s tx us/c rtt us cpu
%
1 0 0 0.00 0.00 0.00 0.00 0.00 -1.00
1 0 0 0.00 0.00 0.00 0.00 0.00 -1.00
1 0 0 0.00 0.00 0.00 0.00 0.00 -1.00
1 0 0 0.00 0.00 0.00 0.00 0.00 -1.00
"
>From vmcore, we can find that clean_list is NULL.
>From the source code, rds_mr_flushd calls rds_ib_mr_pool_flush_worker.
Then rds_ib_mr_pool_flush_worker calls
"
rds_ib_flush_mr_pool(pool, 0, NULL);
"
Then in function
"
int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool,
int free_all, struct rds_ib_mr **ibmr_ret)
"
ibmr_ret is NULL.
In the source code,
"
...
list_to_llist_nodes(pool, &unmap_list, &clean_nodes, &clean_tail);
if (ibmr_ret)
*ibmr_ret = llist_entry(clean_nodes, struct rds_ib_mr, llnode);
/* more than one entry in llist nodes */
if (clean_nodes->next)
llist_add_batch(clean_nodes->next, clean_tail, &pool->clean_list);
...
"
When ibmr_ret is NULL, llist_entry is not executed. clean_nodes->next
instead of clean_nodes is added in clean_list.
So clean_nodes is discarded. It can not be used again.
The workqueue is executed periodically. So more and more clean_nodes are
discarded. Finally the clean_list is NULL.
Then this problem will occur.
Fixes: 1bc144b62524 ("net, rds, Replace xlist in net/rds/xlist.h with llist")
Signed-off-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/rds')
| -rw-r--r-- | net/rds/ib_rdma.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/net/rds/ib_rdma.c b/net/rds/ib_rdma.c index d664e9ade74d..0b347f46b2f4 100644 --- a/net/rds/ib_rdma.c +++ b/net/rds/ib_rdma.c @@ -428,12 +428,14 @@ int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool, wait_clean_list_grace(); list_to_llist_nodes(pool, &unmap_list, &clean_nodes, &clean_tail); - if (ibmr_ret) + if (ibmr_ret) { *ibmr_ret = llist_entry(clean_nodes, struct rds_ib_mr, llnode); - + clean_nodes = clean_nodes->next; + } /* more than one entry in llist nodes */ - if (clean_nodes->next) - llist_add_batch(clean_nodes->next, clean_tail, &pool->clean_list); + if (clean_nodes) + llist_add_batch(clean_nodes, clean_tail, + &pool->clean_list); } |