From: Tao Liu thomas.liu@ucloud.cn
[ Upstream commit ca465e1f1f9b38fe916a36f7d80c5d25f2337c81 ]
If cma_listen_on_all() fails it leaves the per-device ID still on the listen_list but the state is not set to RDMA_CM_ADDR_BOUND.
When the cmid is eventually destroyed cma_cancel_listens() is not called due to the wrong state, however the per-device IDs are still holding the refcount preventing the ID from being destroyed, thus deadlocking:
task:rping state:D stack: 0 pid:19605 ppid: 47036 flags:0x00000084 Call Trace: __schedule+0x29a/0x780 ? free_unref_page_commit+0x9b/0x110 schedule+0x3c/0xa0 schedule_timeout+0x215/0x2b0 ? __flush_work+0x19e/0x1e0 wait_for_completion+0x8d/0xf0 _destroy_id+0x144/0x210 [rdma_cm] ucma_close_id+0x2b/0x40 [rdma_ucm] __destroy_id+0x93/0x2c0 [rdma_ucm] ? __xa_erase+0x4a/0xa0 ucma_destroy_id+0x9a/0x120 [rdma_ucm] ucma_write+0xb8/0x130 [rdma_ucm] vfs_write+0xb4/0x250 ksys_write+0xb5/0xd0 ? syscall_trace_enter.isra.19+0x123/0x190 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9
Ensure that cma_listen_on_all() atomically unwinds its action under the lock during error.
Fixes: c80a0c52d85c ("RDMA/cma: Add missing error handling of listen_id") Link: https://lore.kernel.org/r/20210913093344.17230-1-thomas.liu@ucloud.cn Signed-off-by: Tao Liu thomas.liu@ucloud.cn Reviewed-by: Leon Romanovsky leonro@nvidia.com Signed-off-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/infiniband/core/cma.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c index 107462905b21..dbbacc8e9273 100644 --- a/drivers/infiniband/core/cma.c +++ b/drivers/infiniband/core/cma.c @@ -1746,15 +1746,16 @@ static void cma_cancel_route(struct rdma_id_private *id_priv) } }
-static void cma_cancel_listens(struct rdma_id_private *id_priv) +static void _cma_cancel_listens(struct rdma_id_private *id_priv) { struct rdma_id_private *dev_id_priv;
+ lockdep_assert_held(&lock); + /* * Remove from listen_any_list to prevent added devices from spawning * additional listen requests. */ - mutex_lock(&lock); list_del(&id_priv->list);
while (!list_empty(&id_priv->listen_list)) { @@ -1768,6 +1769,12 @@ static void cma_cancel_listens(struct rdma_id_private *id_priv) rdma_destroy_id(&dev_id_priv->id); mutex_lock(&lock); } +} + +static void cma_cancel_listens(struct rdma_id_private *id_priv) +{ + mutex_lock(&lock); + _cma_cancel_listens(id_priv); mutex_unlock(&lock); }
@@ -2587,7 +2594,7 @@ static int cma_listen_on_all(struct rdma_id_private *id_priv) return 0;
err_listen: - list_del(&id_priv->list); + _cma_cancel_listens(id_priv); mutex_unlock(&lock); if (to_destroy) rdma_destroy_id(&to_destroy->id);