We encountered a use-after-free bug when unloading the driver:

[ 3562.116059] BUG: KASAN: use-after-free in ib_mad_post_receive_mads+0xddc/0xed0 [ib_core]
[ 3562.117233] Read of size 4 at addr ffff8882ca5aa868 by task kworker/u13:2/23862
[ 3562.118385]
[ 3562.119519] CPU: 2 PID: 23862 Comm: kworker/u13:2 Tainted: G           OE     5.1.0-for-upstream-dbg-2019-05-19_16-44-30-13 #1
[ 3562.121806] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu2 04/01/2014
[ 3562.123075] Workqueue: ib-comp-unb-wq ib_cq_poll_work [ib_core]
[ 3562.124383] Call Trace:
[ 3562.125640]  dump_stack+0x9a/0xeb
[ 3562.126911]  print_address_description+0xe3/0x2e0
[ 3562.128223]  ? ib_mad_post_receive_mads+0xddc/0xed0 [ib_core]
[ 3562.129545]  __kasan_report+0x15c/0x1df
[ 3562.130866]  ? ib_mad_post_receive_mads+0xddc/0xed0 [ib_core]
[ 3562.132174]  kasan_report+0xe/0x20
[ 3562.133514]  ib_mad_post_receive_mads+0xddc/0xed0 [ib_core]
[ 3562.134835]  ? find_mad_agent+0xa00/0xa00 [ib_core]
[ 3562.136158]  ? qlist_free_all+0x51/0xb0
[ 3562.137498]  ? mlx4_ib_sqp_comp_worker+0x1970/0x1970 [mlx4_ib]
[ 3562.138833]  ? quarantine_reduce+0x1fa/0x270
[ 3562.140171]  ? kasan_unpoison_shadow+0x30/0x40
[ 3562.141522]  ib_mad_recv_done+0xdf6/0x3000 [ib_core]
[ 3562.142880]  ? _raw_spin_unlock_irqrestore+0x46/0x70
[ 3562.144277]  ? ib_mad_send_done+0x1810/0x1810 [ib_core]
[ 3562.145649]  ? mlx4_ib_destroy_cq+0x2a0/0x2a0 [mlx4_ib]
[ 3562.147008]  ? _raw_spin_unlock_irqrestore+0x46/0x70
[ 3562.148380]  ? debug_object_deactivate+0x2b9/0x4a0
[ 3562.149814]  __ib_process_cq+0xe2/0x1d0 [ib_core]
[ 3562.151195]  ib_cq_poll_work+0x45/0xf0 [ib_core]
[ 3562.152577]  process_one_work+0x90c/0x1860
[ 3562.153959]  ? pwq_dec_nr_in_flight+0x320/0x320
[ 3562.155320]  worker_thread+0x87/0xbb0
[ 3562.156687]  ? __kthread_parkme+0xb6/0x180
[ 3562.158058]  ? process_one_work+0x1860/0x1860
[ 3562.159429]  kthread+0x320/0x3e0
[ 3562.161391]  ? kthread_park+0x120/0x120
[ 3562.162744]  ret_from_fork+0x24/0x30
...
[ 3562.187615] Freed by task 31682:
[ 3562.188602]  save_stack+0x19/0x80
[ 3562.189586]  __kasan_slab_free+0x11d/0x160
[ 3562.190571]  kfree+0xf5/0x2f0
[ 3562.191552]  ib_mad_port_close+0x200/0x380 [ib_core]
[ 3562.192538]  ib_mad_remove_device+0xf0/0x230 [ib_core]
[ 3562.193538]  remove_client_context+0xa6/0xe0 [ib_core]
[ 3562.194514]  disable_device+0x14e/0x260 [ib_core]
[ 3562.195488]  __ib_unregister_device+0x79/0x150 [ib_core]
[ 3562.196462]  ib_unregister_device+0x21/0x30 [ib_core]
[ 3562.197439]  mlx4_ib_remove+0x162/0x690 [mlx4_ib]
[ 3562.198408]  mlx4_remove_device+0x204/0x2c0 [mlx4_core]
[ 3562.199381]  mlx4_unregister_interface+0x49/0x1d0 [mlx4_core]
[ 3562.200356]  mlx4_ib_cleanup+0xc/0x1d [mlx4_ib]
[ 3562.201329]  __x64_sys_delete_module+0x2d2/0x400
[ 3562.202288]  do_syscall_64+0x95/0x470
[ 3562.203277]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

The problem was that the MAD PD was deallocated before the MAD CQ.
There was completion work pending for the CQ when the PD got deallocated.
When the mad completion handling reached procedure
ib_mad_post_receive_mads(), we got a use-after-free bug in the following
line of code in that procedure:
   sg_list.lkey = qp_info->port_priv->pd->local_dma_lkey;
(the pd pointer in the above line is no longer valid, because the
pd has been deallocated).

We fix this by allocating the PD before the CQ in procedure
ib_mad_port_open(), and deallocating the PD after freeing the CQ
in procedure ib_mad_port_close().

Since the CQ completion work queue is flushed during ib_free_cq(),
no completions will be pending for that CQ when the PD is later
deallocated.

Note that freeing the CQ before deallocating the PD is the practice
in the ULPs.

Fixes: 4be90bc6 ("IB/mad: Remove ib_get_dma_mr calls")
Signed-off-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Link: https://lore.kernel.org/r/20190801121449.24973-1-leon@kernel.orgSigned-off-by: NDoug Ledford <dledford@redhat.com>

Decode more information from the packet and include it in the trace.
Reviewed-by: N"Ruhl, Michael J" <michael.j.ruhl@intel.com>
Signed-off-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Trace agent details when agents are [un]registered.  In addition, report
agent details on send/recv.
Reviewed-by: N"Ruhl, Michael J" <michael.j.ruhl@intel.com>
Reviewed-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Trace received MAD details.
Reviewed-by: N"Ruhl, Michael J" <michael.j.ruhl@intel.com>
Reviewed-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Use the standard Linux trace mechanism to trace MADs being sent.  4 trace
points are added, when the MAD is posted to the qp, when the MAD is
completed, if a MAD is resent, and when the MAD completes in error.
Reviewed-by: N"Ruhl, Michael J" <michael.j.ruhl@intel.com>
Suggested-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Pull the allocation function out into its own function to reduce the
length of ib_register_mad_agent() a little and keep all the allocation
logic together.
Signed-off-by: NMatthew Wilcox <willy@infradead.org>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

We have many loops iterating over all of the end port numbers on a struct
ib_device, simplify them with a for_each helper.
Reviewed-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Make all the required change to start use the ib_device_ops structure.
Signed-off-by: NKamal Heib <kamalheib1@gmail.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The ucma users supply timeout in u32 format, it means that any number
with most significant bit set will be converted to negative value
by various rdma_*, cma_* and sa_query functions, which treat timeout
as int.

In the lowest level, the timeout is converted back to be unsigned long.
Remove this ambiguous conversion by updating all function signatures to
receive unsigned long.
Reported-by: NNoa Osherovich <noaos@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

While registering a mad agent, a user space can trigger various errors
and flood the logs.

Therefore, decrease verbosity and rate limit such error messages.
While we are at it, use __func__ to print function name.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

When requested QP type is not supported for a {device, port}, return the
error right away before validating all parameters during mad agent
registration time.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Reviewed-by: NDaniel Jurgens <danielj@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The upstream kernel commit cited below modified the workqueue in the
new CQ API to be bound to a specific CPU (instead of being unbound).
This caused ALL users of the new CQ API to use the same bound WQ.

Specifically, MAD handling was severely delayed when the CPU bound
to the WQ was busy handling (higher priority) interrupts.

This caused a delay in the MAD "heartbeat" response handling,
which resulted in ports being incorrectly classified as "down".

To fix this, add a new "unbound" WQ type to the new CQ API, so that users
have the option to choose either a bound WQ or an unbound WQ.

For MADs, choose the new "unbound" WQ.

Fixes: b7363e67 ("IB/device: Convert ib-comp-wq to be CPU-bound")
Signed-off-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.m>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Instead of declaring and passing a dummy 'bad_wr' pointer, pass NULL
as third argument to ib_post_(send|recv|srq_recv)().
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Allocate agent IDs from a global IDR instead of an atomic variable.
This eliminates the possibility of reusing an ID which is already in
use after 4 billion registrations.  We limit the assigned ID to be less
than 2^24 as the mlx4 driver uses the most significant byte of the agent
ID to store the slave number.  Users unlucky enough to see a collision
between agent numbers and slave numbers see messages like:

 mlx4_ib: egress mad has non-null tid msb:1 class:4 slave:0

and the MAD layer stops working.

We look up the agent under protection of the RCU lock, which means we
have to free the agent using kfree_rcu, and only increment the reference
counter if it is not 0.
Signed-off-by: NMatthew Wilcox <mawilcox@microsoft.com>
Reported-by: NHans Westgaard Ry <hans.westgaard.ry@oracle.com>
Acked-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Tested-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Document this (it's implicitly true due to sleeping operations already
in use in both registration and deregistration).  Use this fact to use
spin_lock_irq instead of spin_lock_irqsave.  This improves performance
slightly.
Signed-off-by: NMatthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

If the gid_attr argument is NULL then the functions behave identically to
rdma_query_gid. ib_query_gid just calls ib_get_cached_gid, so everything
can be consolidated to one function.

Now that all callers either use rdma_query_gid() or ib_get_cached_gid(),
ib_query_gid() API is removed.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Let's perform checks in-place instead of BUG_ONs.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

There is no need to check existence of mad_queue, because we already did
pointer dereference before call to dequeue_mad().
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Currently, the kernel protects access to the agent ID allocator on a per
port basis using a spinlock, so it is impossible for two apps/threads on
the same port to get the same TID, but it is entirely possible for two
threads on different ports to end up with the same TID.

As this can be confusing (regardless of it being legal according to the
IB Spec 1.3, C13-18.1.1, in section 13.4.6.4 - TransactionID usage),
and as the rdma-core user space API for /dev/umad devices implies unique
TIDs even across ports, make the TID an atomic type so that no two
allocations, regardless of port number, will be the same.
Signed-off-by: NHåkon Bugge <haakon.bugge@oracle.com>
Reviewed-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NZhu Yanjun <yanjun.zhu@oracle.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

These duplicate includes have been found with scripts/checkincludes.pl but
they have been removed manually to avoid removing false positives.
Signed-off-by: NPravin Shedge <pravin.shedge4linux@gmail.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Below kernel crash is observed when Pkey security enforcement fails on
received MADs. This issue is reported in [1].

ib_free_recv_mad() accesses the rmpp_list, whose initialization is
needed before accessing it.
When security enformcent fails on received MADs, MAD processing avoided
due to security checks failed.

OpenSM[3770]: SM port is down
kernel: BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
kernel: IP: ib_free_recv_mad+0x44/0xa0 [ib_core]
kernel: PGD 0
kernel: P4D 0
kernel:
kernel: Oops: 0002 [#1] SMP
kernel: CPU: 0 PID: 2833 Comm: kworker/0:1H Tainted: P          IO    4.13.4-1-pve #1
kernel: Hardware name: Dell       XS23-TY3        /9CMP63, BIOS 1.71 09/17/2013
kernel: Workqueue: ib-comp-wq ib_cq_poll_work [ib_core]
kernel: task: ffffa069c6541600 task.stack: ffffb9a729054000
kernel: RIP: 0010:ib_free_recv_mad+0x44/0xa0 [ib_core]
kernel: RSP: 0018:ffffb9a729057d38 EFLAGS: 00010286
kernel: RAX: ffffa069cb138a48 RBX: ffffa069cb138a10 RCX: 0000000000000000
kernel: RDX: ffffb9a729057d38 RSI: 0000000000000000 RDI: ffffa069cb138a20
kernel: RBP: ffffb9a729057d60 R08: ffffa072d2d49800 R09: ffffa069cb138ae0
kernel: R10: ffffa069cb138ae0 R11: ffffa072b3994e00 R12: ffffb9a729057d38
kernel: R13: ffffa069d1c90000 R14: 0000000000000000 R15: ffffa069d1c90880
kernel: FS:  0000000000000000(0000) GS:ffffa069dba00000(0000) knlGS:0000000000000000
kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
kernel: CR2: 0000000000000008 CR3: 00000011f51f2000 CR4: 00000000000006f0
kernel: Call Trace:
kernel:  ib_mad_recv_done+0x5cc/0xb50 [ib_core]
kernel:  __ib_process_cq+0x5c/0xb0 [ib_core]
kernel:  ib_cq_poll_work+0x20/0x60 [ib_core]
kernel:  process_one_work+0x1e9/0x410
kernel:  worker_thread+0x4b/0x410
kernel:  kthread+0x109/0x140
kernel:  ? process_one_work+0x410/0x410
kernel:  ? kthread_create_on_node+0x70/0x70
kernel:  ? SyS_exit_group+0x14/0x20
kernel:  ret_from_fork+0x25/0x30
kernel: RIP: ib_free_recv_mad+0x44/0xa0 [ib_core] RSP: ffffb9a729057d38
kernel: CR2: 0000000000000008

[1] : https://www.spinics.net/lists/linux-rdma/msg56190.html

Fixes: 47a2b338 ("IB/core: Enforce security on management datagrams")
Cc: stable@vger.kernel.org # 4.13+
Signed-off-by: NParav Pandit <parav@mellanox.com>
Reported-by: NChris Blake <chrisrblake93@gmail.com>
Reviewed-by: NDaniel Jurgens <danielj@mellanox.com>
Reviewed-by: NHal Rosenstock <hal@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Allocate and free a security context when creating and destroying a MAD
agent.  This context is used for controlling access to PKeys and sending
and receiving SMPs.

When sending or receiving a MAD check that the agent has permission to
access the PKey for the Subnet Prefix of the port.

During MAD and snoop agent registration for SMI QPs check that the
calling process has permission to access the manage the subnet  and
register a callback with the LSM to be notified of policy changes. When
notificaiton of a policy change occurs recheck permission and set a flag
indicating sending and receiving SMPs is allowed.

When sending and receiving MADs check that the agent has access to the
SMI if it's on an SMI QP.  Because security policy can change it's
possible permission was allowed when creating the agent, but no longer
is.
Signed-off-by: NDaniel Jurgens <danielj@mellanox.com>
Acked-by: NDoug Ledford <dledford@redhat.com>
[PM: remove the LSM hook init code]
Signed-off-by: NPaul Moore <paul@paul-moore.com>

Modify core and driver components to use accessor functions
introduced to access individual fields of rdma_ah_attr
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NDon Hiatt <don.hiatt@intel.com>
Reviewed-by: NSean Hefty <sean.hefty@intel.com>
Reviewed-by: NNiranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Rename ib_query_ah to rdma_query_ah so its in sync with the
rename of the ib address handle attribute
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NDon Hiatt <don.hiatt@intel.com>
Reviewed-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This patch simply renames struct ib_ah_attr to
rdma_ah_attr as these fields specify attributes that are
not necessarily specific to IB.
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NDon Hiatt <don.hiatt@intel.com>
Reviewed-by: NNiranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Reviewed-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The function ib_unregister_mad_agent always returns zero. And
this returned value is not checked. As such, chane the return
type to void.

CC: Joe Jin <joe.jin@oracle.com>
CC: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: NZhu Yanjun <yanjun.zhu@oracle.com>
Reviewed-by: NYuval Shaia <yuval.shaia@oracle.com>
Reviewed-by: NHal Rosenstock <hal@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Print the invalid port number to ease troubleshooting.
Signed-off-by: NYuval Shaia <yuval.shaia@oracle.com>
Reviewed-by: NLeon Romanovsky <leonro@mellanox.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The array ib_mad_mgmt_class_table.method_table has MAX_MGMT_CLASS
(80) elements. Hence compare the array index with that value instead
of with IB_MGMT_MAX_METHODS (128). This patch avoids that Coverity
reports the following:

Overrunning array class->method_table of 80 8-byte elements at element index 127 (byte offset 1016) using index convert_mgmt_class(mad_hdr->mgmt_class) (which evaluates to 127).

Fixes: commit b7ab0b19 ("IB/mad: Verify mgmt class in received MADs")
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: NHal Rosenstock <hal@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

and rename class version define to indicate SM rather than SMP or SMI
Signed-off-by: NHal Rosenstock <hal@mellanox.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The prints after [k|v][m|z|c]alloc() functions are not needed,
because in case of failure, allocator will print their internal
error prints anyway.
Signed-off-by: NLeon Romanovsky <leon@kernel.org>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The workqueue "ib_nl" queues work items &ib_nl_timed_work and
&mad_agent_priv->local_work. It has been identity converted.

WQ_MEM_RECLAIM has been set to ensure forward progress under
memory pressure.
Signed-off-by: NBhaktipriya Shridhar <bhaktipriya96@gmail.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Instead of exposing ib_get_dma_mr to ULPs and letting them use it more or
less unchecked, this moves the capability of creating a global rkey into
the RDMA core, where it can be easily audited.  It also prints a warning
everytime this feature is used as well.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NJason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Make indentation consistent. Detected by smatch.
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Cc: Hal Rosenstock <hal@mellanox.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Reviewed-By: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NHal Rosenstock <hal@mellanox.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Consolidate ib_mad into ib_core, this commit eliminates
ib_mad.ko and makes it part of ib_core.ko
Signed-off-by: NMark Bloch <markb@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Remove the local workqueue to process mad completions and use the CQ API
instead.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHal Rosenstock <hal@mellanox.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Stop abusing wr_id and just pass the parameter explicitly.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHal Rosenstock <hal@mellanox.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

It was found that when a process was rapidly sending MADs other processes could
be hung in their unregister calls.

This would happen when process A was injecting packets fast enough that the
single threaded workqueue was never exiting ib_mad_completion_handler.
Therefore when process B called flush_workqueue via the unregister call it
would hang until process A stopped sending MADs.

The fix is to periodically reschedule ib_mad_completion_handler after
processing a large number of completions.  The number of completions chosen was
decided based on the defaults for the recv queue size.  However, it was kept
fixed such that increasing those queue sizes would not adversely affect
fairness in the future.
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Receipt of CM MAD with other than the Send method for an attribute
other than the ClassPortInfo attribute is invalid.

CM attributes other than ClassPortInfo only use the send method.

The SRP initiator does not maintain a timeout policy for CM connect
requests relies on the CM layer to do that. The result was that
the SRP initiator hung as the connect request never completed.

A new SRP target has been observed to respond to Send CM REQ
with GetResp of CM REQ with bad status. This is non conformant
with IBA spec but exposes a vulnerability in the current MAD/CM
code which will respond to the incoming GetResp of CM REQ as if
it was a valid incoming Send of CM REQ rather than tossing
this on the floor. It also causes the MAD layer not to
retransmit the original REQ even though it has not received a REP.
Reviewed-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NHal Rosenstock <hal@mellanox.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Adding an ability to query the IB cache by a netdev and get the
attributes of a GID. These parameters are necessary in order to
successfully resolve the required GID (when the netdevice is known)
and get the Ethernet L2 attributes from a GID.
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Reviewed-By: NDevesh Sharma <devesh.sharma@avagotech.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This patch split up struct ib_send_wr so that all non-trivial verbs
use their own structure which embedds struct ib_send_wr.  This dramaticly
shrinks the size of a WR for most common operations:

sizeof(struct ib_send_wr) (old):	96

sizeof(struct ib_send_wr):		48
sizeof(struct ib_rdma_wr):		64
sizeof(struct ib_atomic_wr):		96
sizeof(struct ib_ud_wr):		88
sizeof(struct ib_fast_reg_wr):		88
sizeof(struct ib_bind_mw_wr):		96
sizeof(struct ib_sig_handover_wr):	80

And with Sagi's pending MR rework the fast registration WR will also be
down to a reasonable size:

sizeof(struct ib_fastreg_wr):		64
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> [srp, srpt]
Reviewed-by: Chuck Lever <chuck.lever@oracle.com> [sunrpc]
Tested-by: NHaggai Eran <haggaie@mellanox.com>
Tested-by: NSagi Grimberg <sagig@mellanox.com>
Tested-by: NSteve Wise <swise@opengridcomputing.com>