OpenCloudOS-Kernel/drivers/infiniband
Michael J. Ruhl f683c80ca6 IB/hfi1: Resolve kernel panics by reference counting receive contexts
Base receive contexts can be used by sub contexts.  Because of this,
resources for the context cannot be completely freed until all sub
contexts are done using the base context.

Introduce a reference count so that the base receive context can be
freed only when all sub contexts are done with it.

Use the provided function call for setting default send context
integrity rather than the manual method.

The cleanup path does not set all variables back to NULL after freeing
resources.  Since the clean up code can get called more than once,
(e.g. during context close and on the error path), it is necessary to
make sure that all the variables are NULLed.

Possible crash are:

BUG: unable to handle kernel paging request at 0000000001908900
IP: read_csr+0x24/0x30 [hfi1]
RIP: 0010:read_csr+0x24/0x30 [hfi1]
Call Trace:
 sc_disable+0x40/0x110 [hfi1]
 hfi1_file_close+0x16f/0x360 [hfi1]
 __fput+0xe7/0x210
 ____fput+0xe/0x10

or

kernel BUG at mm/slub.c:3877!
RIP: 0010:kfree+0x14f/0x170
Call Trace:
 hfi1_free_ctxtdata+0x19a/0x2b0 [hfi1]
 ? hfi1_user_exp_rcv_grp_free+0x73/0x80 [hfi1]
 hfi1_file_close+0x20f/0x360 [hfi1]
 __fput+0xe7/0x210
 ____fput+0xe/0x10

Fixes: Commit 62239fc6e5 ("IB/hfi1: Clean up on context initialization failure")
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-06-27 16:58:13 -04:00
..
core IB/core: Allow QP state transition from reset to error 2017-06-27 16:58:12 -04:00
hw IB/hfi1: Resolve kernel panics by reference counting receive contexts 2017-06-27 16:58:13 -04:00
sw IB/hfi1: Use QPN mask to avoid overflow 2017-06-27 16:58:12 -04:00
ulp IB/core,rdmavt,hfi1,opa-vnic: Send OPA cap_mask3 in trap 2017-06-27 16:58:12 -04:00
Kconfig IB/opa-vnic: Virtual Network Interface Controller (VNIC) netdev 2017-04-20 12:01:38 -04:00
Makefile IB/rdmavt: Create module framework and handle driver registration 2016-03-10 20:37:04 -05:00