IB/mlx4: Fix possible deadlock on sm_lock spinlock

The sm_lock spinlock is taken in the process context by
mlx4_ib_modify_device, and in the interrupt context by update_sm_ah,
so we need to take that spinlock with irqsave, and release it with
irqrestore.

Lockdeps reports this as follows:

    [ INFO: inconsistent lock state ]
    3.5.0+ #20 Not tainted
    inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
    swapper/0/0 [HC1[1]:SC0[0]:HE0:SE1] takes:
    (&(&ibdev->sm_lock)->rlock){?.+...}, at: [<ffffffffa028af1d>] update_sm_ah+0xad/0x100 [mlx4_ib]
    {HARDIRQ-ON-W} state was registered at:
      [<ffffffff810b84a0>] mark_irqflags+0x120/0x190
      [<ffffffff810b9ce7>] __lock_acquire+0x307/0x4c0
      [<ffffffff810b9f51>] lock_acquire+0xb1/0x150
      [<ffffffff815523b1>] _raw_spin_lock+0x41/0x50
      [<ffffffffa028d563>] mlx4_ib_modify_device+0x63/0x240 [mlx4_ib]
      [<ffffffffa026d1fc>] ib_modify_device+0x1c/0x20 [ib_core]
      [<ffffffffa026c353>] set_node_desc+0x83/0xc0 [ib_core]
      [<ffffffff8136a150>] dev_attr_store+0x20/0x30
      [<ffffffff81201fd6>] sysfs_write_file+0xe6/0x170
      [<ffffffff8118da38>] vfs_write+0xc8/0x190
      [<ffffffff8118dc01>] sys_write+0x51/0x90
      [<ffffffff8155b869>] system_call_fastpath+0x16/0x1b

    ...
    *** DEADLOCK ***

    1 lock held by swapper/0/0:

    stack backtrace:
    Pid: 0, comm: swapper/0 Not tainted 3.5.0+ #20
    Call Trace:
    <IRQ>  [<ffffffff810b7bea>] print_usage_bug+0x18a/0x190
    [<ffffffff810b7370>] ? print_irq_inversion_bug+0x210/0x210
    [<ffffffff810b7fb2>] mark_lock_irq+0xf2/0x280
    [<ffffffff810b8290>] mark_lock+0x150/0x240
    [<ffffffff810b84ef>] mark_irqflags+0x16f/0x190
    [<ffffffff810b9ce7>] __lock_acquire+0x307/0x4c0
    [<ffffffffa028af1d>] ? update_sm_ah+0xad/0x100 [mlx4_ib]
    [<ffffffff810b9f51>] lock_acquire+0xb1/0x150
    [<ffffffffa028af1d>] ? update_sm_ah+0xad/0x100 [mlx4_ib]
    [<ffffffff815523b1>] _raw_spin_lock+0x41/0x50
    [<ffffffffa028af1d>] ? update_sm_ah+0xad/0x100 [mlx4_ib]
    [<ffffffffa026b2fa>] ? ib_create_ah+0x1a/0x40 [ib_core]
    [<ffffffffa028af1d>] update_sm_ah+0xad/0x100 [mlx4_ib]
    [<ffffffff810c27c3>] ? is_module_address+0x23/0x30
    [<ffffffffa028b05b>] handle_port_mgmt_change_event+0xeb/0x150 [mlx4_ib]
    [<ffffffffa028c177>] mlx4_ib_event+0x117/0x160 [mlx4_ib]
    [<ffffffff81552501>] ? _raw_spin_lock_irqsave+0x61/0x70
    [<ffffffffa022718c>] mlx4_dispatch_event+0x6c/0x90 [mlx4_core]
    [<ffffffffa0221b40>] mlx4_eq_int+0x500/0x950 [mlx4_core]

Reported by: Or Gerlitz <ogerlitz@mellanox.com>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <roland@purestorage.com>
serial: Change Kconfig entry for CLPS711X-target

This trivial patch adds a short description for SERIAL_CLPS711X Kconfig
entry, removes excess dependence on the ARM-platform (this is done
globally for the platform), allows the driver to be compiled by default
and removes unnecessary description about GRUB and LILO, because these
bootloaders do not supported this platform.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: ifx6x60: fix paging fault on spi_register_driver

[  117.240866] BUG: unable to handle kernel paging request at 815b627c
[  117.240866] IP: [<813fe94b>] spi_register_driver+0xb/0x50
...
[  117.240866] Call Trace:
[  117.240866]  [<817de977>] ifx_spi_init+0xbe/0xf0

The root cause is, spi_register_driver() is trying to write into the
passed *const* struct spi_driver.

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
RDMA/ocrdma: Don't call vlan_dev_real_dev() for non-VLAN netdevs

If CONFIG_VLAN_8021Q is not set, then vlan_dev_real_dev() just goes BUG(),
so we shouldn't call it unless we're actually dealing with a VLAN netdev.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
RDMA/ucma.c: Fix for events with wrong context on iWARP

It is possible for asynchronous RDMA_CM_EVENT_ESTABLISHED events to be
generated with ctx->uid == 0, because ucma_set_event_context() copies
ctx->uid to the event structure outside of ctx->file->mut.  This leads
to a crash in the userspace library, since it gets a bogus event.

Fix this by taking the mutex a bit earlier in ucma_event_handler.

Signed-off-by: Tatyana Nikolova <Tatyana.E.Nikolova@intel.com>
Signed-off-by: Sean Hefty <Sean.Hefty@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
IB/ipoib: Add missing locking when CM object is deleted

Commit b63b70d87741 ("IPoIB: Use a private hash table for path lookup
in xmit path") introduced a bug where in ipoib_cm_destroy_tx() a CM
object is moved between lists without any supported locking.  Under a
stress test, this eventually leads to list corruption and a crash.

Previously when this routine was called, callers were taking the
device priv lock.  Currently this function is called from the RCU
callback associated with neighbour deletion.  Fix the race by taking
the same lock we used to before.

Signed-off-by: Shlomo Pongratz <shlomop@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
IB/ipoib: Fix RCU pointer dereference of wrong object

Commit b63b70d87741 ("IPoIB: Use a private hash table for path lookup
in xmit path") introduced a bug where in ipoib_neigh_free() (which is
called from a few errors flows in the driver), rcu_dereference() is
invoked with the wrong pointer object, which results in a crash.

Signed-off-by: Shlomo Pongratz <shlomop@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
IB: Fix typos in infiniband drivers

Correct spelling typos in comments in drivers/infiniband.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
IB/qib: Fix error return code in qib_init_7322_variables()

Convert a 0 error return code to a negative one, as returned elsewhere
in the function.

A simplified version of the semantic match that finds this problem is
as follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
identifier ret;
expression e,e1,e2,e3,e4,x;
@@

(
if (\(ret != 0\|ret < 0\) || ...) { ... return ...; }
|
ret = 0
)
... when != ret = e1
*x = \(kmalloc\|kzalloc\|kcalloc\|devm_kzalloc\|ioremap\|ioremap_nocache\|devm_ioremap\|devm_ioremap_nocache\)(...);
... when != x = e2
    when != ret = e3
*if (x == NULL || ...)
{
  ... when != ret = e4
*  return ret;
}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
IB/srp: Fix a race condition

Avoid a crash caused by the scmnd->scsi_done(scmnd) call in
srp_process_rsp() being invoked with scsi_done == NULL.  This can
happen if a reply is received during or after a command abort.

Reported-by: Joseph Glanville <joseph.glanville@orionvm.com.au>
Reference: http://marc.info/?l=linux-rdma&m=134314367801595
Cc: <stable@vger.kernel.org>
Acked-by: David Dillow <dillowda@ornl.gov>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Roland Dreier <roland@purestorage.com>
mlx4_core: Allow large mlx4_buddy bitmaps

mlx4_buddy_init uses kmalloc() to allocate bitmaps, which fails when
the required size is beyond the max supported value (or when memory is
too fragmented to handle a huge allocation).  Extend this to use use
vmalloc() if kmalloc() fails, and take that into account when freeing
the bitmaps as well.

This fixes a driver load failure when log num mtt is 26 or higher, and
is a step in the direction of allowing to register huge amounts of
memory on large memory systems.

Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
mlx4_core: Fix integer overflow issues around MTT table

Fix some issues around int variables used in data structures related
to memory registration.

Handle int overflow in mlx4_init_icm_table by using a u64 intermediate
variable and changing struct mlx4_icm_table num_obj field to be u32.

Change some more fields/variables to use u32 instead of int to prevent
a case where the variable becomes negative when bit 31 is set.

Also subtract log_mtts_per_seg from the exponent when computing
num_mtt, since its added later on in that very same code area.

This and the previous commit fixes some issues which actually prevent
commit db5a7a65c058 ("mlx4_core: Scale size of MTT table with system
RAM") from working.  Now, when the number of MTTs is scaled with the
size of the RAM we can map up to 8TB.

Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
mlx4_core: Clean up buddy bitmap allocation

 - Use kcalloc() / vzalloc() instead of an extra bitmap_zero().
 - Add __GFP_NOWARN to kcalloc() since we'll try vzalloc() if it fails.

Signed-off-by: Roland Dreier <roland@purestorage.com>
IB/mlx4: Check iboe netdev pointer before dereferencing it

Unlike other parts of the mlx4_ib code, the function build_mlx_header()
doesn't check if the iboe netdev of the given port is valid before
dereferencing it, which can cause a crash if the ethernet interface
has already been taken down.

Fix this by checking for a valid netdev pointer before using it to get
the port MAC address.

Signed-off-by: Kleber Sacilotto de Souza <klebers@linux.vnet.ibm.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Merge branches 'cma', 'ipoib', 'misc', 'mlx4', 'ocrdma', 'qib' and 'srp' into for-next
serial: mxs-auart: fix the wrong RTS hardware flow control

Without checking if the auart supports the hardware flow control or not,
the old mxs_auart_set_mctrl() asserted the RTS pin blindly.

This will causes the auart receives wrong data in the following case:
   The far-end has already started the write operation, and wait for
the auart asserts the RTS pin. Then the auart starts the read operation,
but mxs_auart_set_mctrl() may be called before we set the RTSCTS in the
mxs_auart_settermios(). So the RTS pin is asserted in a wrong situation,
and we get the wrong data in the end.

This bug has been catched when I connect the mx23(DTE) to the mx53(DCE).

This patch also replaces the AUART_CTRL2_RTS with AUART_CTRL2_RTSEN.
We should use the real the hardware flow control, not the software-controled
hardware flow control.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pmac_zilog,kdb: Fix console poll hook to return instead of loop

kdb <-> kgdb transitioning does not work properly with this UART
driver because the get character routine loops indefinitely as opposed
to returning NO_POLL_CHAR per the expectation of the KDB I/O driver
API.

The symptom is a kernel hang when trying to switch debug modes.

Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge tag 'tty-3.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull TTY fixes from Greg Kroah-Hartman:
 "Here are 4 tiny patches, each fixing a serial driver problem that
  people have reported.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'tty-3.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  pmac_zilog,kdb: Fix console poll hook to return instead of loop
  serial: mxs-auart: fix the wrong RTS hardware flow control
  serial: ifx6x60: fix paging fault on spi_register_driver
  serial: Change Kconfig entry for CLPS711X-target
Merge tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband

Pull infiniband/rdma fixes from Roland Dreier:
 "Grab bag of InfiniBand/RDMA fixes:
   - IPoIB fixes for regressions introduced by path database conversion
   - mlx4 fixes for bugs with large memory systems and regressions from
     SR-IOV patches
   - RDMA CM fix for passing bad event up to userspace
   - Other minor fixes"

* tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
  IB/mlx4: Check iboe netdev pointer before dereferencing it
  mlx4_core: Clean up buddy bitmap allocation
  mlx4_core: Fix integer overflow issues around MTT table
  mlx4_core: Allow large mlx4_buddy bitmaps
  IB/srp: Fix a race condition
  IB/qib: Fix error return code in qib_init_7322_variables()
  IB: Fix typos in infiniband drivers
  IB/ipoib: Fix RCU pointer dereference of wrong object
  IB/ipoib: Add missing locking when CM object is deleted
  RDMA/ucma.c: Fix for events with wrong context on iWARP
  RDMA/ocrdma: Don't call vlan_dev_real_dev() for non-VLAN netdevs
  IB/mlx4: Fix possible deadlock on sm_lock spinlock