IB/hfi1: Do not free hfi1 cdev parent structure early
The deletion of a cdev is not a fence for holding off references to the
structure. The driver attempts to delete the cdev and then proceeds to
free the parent structure, the hfi1_devdata, or dd. This can potentially
lead to a kernel panic in situations where a user has an FD for the cdev
open, and the pci device gets removed. If the user then closes the FD
there will be a NULL dereference when trying to do put on the cdev's
kobject.
Fix this by pointing the cdev's kobject.parent at a new kobject embedded
in its parent structure. Also take a reference when the device is opened
and put it back when it is closed.
Reviewed-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/staging/rdma/hfi1/hfi.h b/drivers/staging/rdma/hfi1/hfi.h
index 337bd2d..4417a0f 100644
--- a/drivers/staging/rdma/hfi1/hfi.h
+++ b/drivers/staging/rdma/hfi1/hfi.h
@@ -1169,6 +1169,7 @@
atomic_t aspm_disabled_cnt;
struct hfi1_affinity *affinity;
+ struct kobject kobj;
};
/* 8051 firmware version helper */