linux/drivers/infiniband
Mike Marciniszyn c62fb260a8 IB/hfi1,IB/qib: Fix qp_stats sleep with rcu read lock held
The qp init function does a kzalloc() while holding the RCU
lock that encounters the following warning with a debug kernel
when a cat of the qp_stats is done:

[  231.723948] rcu_scheduler_active = 1, debug_locks = 0
[  231.731939] 3 locks held by cat/11355:
[  231.736492]  #0:  (debugfs_srcu){......}, at: [<ffffffff813001a5>] debugfs_use_file_start+0x5/0x90
[  231.746955]  #1:  (&p->lock){+.+.+.}, at: [<ffffffff81289a6c>] seq_read+0x4c/0x3c0
[  231.755873]  #2:  (rcu_read_lock){......}, at: [<ffffffffa0a0c535>] _qp_stats_seq_start+0x5/0xd0 [hfi1]
[  231.766862]

The init functions do an implicit next which requires the rcu read lock
before the kzalloc().

Fix for both drivers is to change the scope of the init function to only
do the allocation and the initialization of the just allocated iter.

The implict next is moved back into the respective start functions to fix
the issue.

Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
CC: <stable@vger.kernel.org> # 4.6.x-
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-08-22 14:31:34 -04:00
..
core IB/core: Fix possible memory leak in cma_resolve_iboe_route() 2016-08-22 14:26:54 -04:00
hw IB/hfi1,IB/qib: Fix qp_stats sleep with rcu read lock held 2016-08-22 14:31:34 -04:00
sw Second round of merge items for 4.8 2016-08-04 20:26:31 -04:00
ulp IB/isert: fix error return code in isert_alloc_login_buf() 2016-08-22 14:26:55 -04:00
Kconfig Soft RoCE driver 2016-08-04 11:13:12 -04:00
Makefile IB/rdmavt: Create module framework and handle driver registration 2016-03-10 20:37:04 -05:00