Currently if uverbs is not loaded libibverbs latches into a permanent
disabled state on the first try to ibv_get_device_list. This is not
compatible with hot-plug which could insert the uverbs module at any
later point. Recheck for uverbs presence until we get a successful init
or a hard failure during init.
Cc: stable@xxxxxxxxxxxxxx
Fixes: c632072027a8 ("verbs: Refresh cahced ibv_device list")
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
---
libibverbs/device.c | 17 ++++++++++++++++-
1 file changed, 16 insertions(+), 1 deletion(-)
diff --git a/libibverbs/device.c b/libibverbs/device.c
index 448795a993af21..3900afd3f90bd3 100644
--- a/libibverbs/device.c
+++ b/libibverbs/device.c
@@ -64,7 +64,22 @@ LATEST_SYMVER_FUNC(ibv_get_device_list, 1_1, "IBVERBS_1.1",
pthread_mutex_lock(&dev_list_lock);
if (!initialized) {
- int ret = ibverbs_init();
+ char value[8];
+ int ret;
+
+ /*
+ * The uverbs module is not loaded, this is a ENOSYS return
+ * but it is not a hard failure, we can try again to see if it
+ * has become loaded since.
+ */
+ if (ibv_read_sysfs_file(ibv_get_sysfs_path(),
+ "class/infiniband_verbs/abi_version",
+ value, sizeof(value)) < 0) {
+ errno = -ENOSYS;
+ goto out;
+ }
+
+ ret = ibverbs_init();
initialized = (ret < 0) ? ret : 1;
}
--
2.19.0
