[PATCH 5.4 262/453] RDMA/core: Do not indicate device ready when device enablement fails

From: Greg Kroah-Hartman
Date: Mon Dec 28 2020 - 08:50:27 EST


From: Jack Morgenstein <jackm@xxxxxxxxxxxxxxxxxx>

[ Upstream commit 779e0bf47632c609c59f527f9711ecd3214dccb0 ]

In procedure ib_register_device, procedure kobject_uevent is called
(advertising that the device is ready for userspace usage) even when
device_enable_and_get() returned an error.

As a result, various RDMA modules attempted to register for the device
even while the device driver was preparing to unregister the device.

Fix this by advertising the device availability only after enabling the
device succeeds.

Fixes: e7a5b4aafd82 ("RDMA/device: Don't fire uevent before device is fully initialized")
Link: https://lore.kernel.org/r/20201208073545.9723-3-leon@xxxxxxxxxx
Suggested-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
Signed-off-by: Jack Morgenstein <jackm@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/infiniband/core/device.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
index 59dc9f3cfb376..256d379bba676 100644
--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -1387,9 +1387,6 @@ int ib_register_device(struct ib_device *device, const char *name)
}

ret = enable_device_and_get(device);
- dev_set_uevent_suppress(&device->dev, false);
- /* Mark for userspace that device is ready */
- kobject_uevent(&device->dev.kobj, KOBJ_ADD);
if (ret) {
void (*dealloc_fn)(struct ib_device *);

@@ -1409,8 +1406,12 @@ int ib_register_device(struct ib_device *device, const char *name)
ib_device_put(device);
__ib_unregister_device(device);
device->ops.dealloc_driver = dealloc_fn;
+ dev_set_uevent_suppress(&device->dev, false);
return ret;
}
+ dev_set_uevent_suppress(&device->dev, false);
+ /* Mark for userspace that device is ready */
+ kobject_uevent(&device->dev.kobj, KOBJ_ADD);
ib_device_put(device);

return 0;
--
2.27.0