iio:trigger: Fix use_count race condition

When using more than one trigger consumer it can happen that multiple threads
perform a read-modify-update cycle on 'use_count' concurrently. This can cause
updates to be lost and use_count can get stuck at non-zero value, in which case
the IIO core assumes that at least one thread is still running and will wait for
it to finish before running any trigger handlers again. This effectively renders
the trigger disabled and a reboot is necessary before it can be used again. To
fix this make use_count an atomic variable. Also set it to the number of
consumers before starting the first consumer, otherwise it might happen that
use_count drops to 0 even though not all consumers have been run yet.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Tested-by: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
iio: ti_am335x_adc: Fix wrong samples received on 1st read

Previously we tried to read data form ADC even before ADC sequencer
finished sampling. This led to wrong samples.
We now wait on ADC status register idle bit to be set.

Signed-off-by: Patil, Rachna <rachna@ti.com>
Signed-off-by: Zubair Lutfullah <zubair.lutfullah@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
KVM: s390: move kvm_guest_enter,exit closer to sie

Any uaccess between guest_enter and guest_exit could trigger a page fault,
the page fault handler would handle it as a guest fault and translate a
user address as guest address.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
CC: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: s390: fix pfmf non-quiescing control handling

Fix the test within handle_pfmf() if the host has the NQ key-setting
facility installed.
Right now the code would incorrectly generate a program check in the
guest if the NQ control bit for a pfmf request was set and if the host
has the NQ key-setting facility installed.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
staging: zcache: fix "zcache=" kernel parameter

Commit 835f2f5 ("staging: zcache: enable zcache to be built/loaded as
a module") introduced an incorrect handling of "zcache=" parameter.

Inside zcache_comp_init() function, zcache_comp_name variable is
checked for being empty. If not empty, the above variable is tested
for being compatible with Crypto API. Unfortunately, after that
function ends unconditionally (by the "goto out" directive) and returns:
- non-zero value if verification succeeded, wrongly indicating an error
- zero value if verification failed, falsely informing that function
  zcache_comp_init() ended properly.

A solution to this problem is as following:
1. Move the "goto out" directive inside the "if (!ret)" statement
2. In case that crypto_has_comp() returned 0, change the value of ret
   to non-zero before "goto out" to indicate an error.

This patch replaces an earlier one from Michal Hocko (based on report
from Cristian Rodriguez):

	http://permalink.gmane.org/gmane.linux.kernel.mm/102484

It also addressed the same issue but didn't fix the zcache_comp_init()
for case when the compressor data passed to "zcache=" option was invalid
or unsupported.

Signed-off-by: Piotr Sarna <p.sarna@partner.samsung.com>
[bzolnier: updated patch description]
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: stable <stable@vger.kernel.org> # 3.10
Cc: Cristian Rodriguez <crrodriguez@opensuse.org>
Cc: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usb: core: don't try to reset_device() a port that got just disconnected

The USB hub driver's event handler contains a check to catch SuperSpeed
devices that transitioned into the SS.Inactive state and tries to fix
them with a reset. It decides whether to do a plain hub port reset or
call the usb_reset_device() function based on whether there was a device
attached to the port.

However, there are device/hub combinations (found with a JetFlash
Transcend mass storage stick (8564:1000) on the root hub of an Intel
LynxPoint PCH) which can transition to the SS.Inactive state on
disconnect (and stay there long enough for the host to notice). In this
case, above-mentioned reset check will call usb_reset_device() on the
stale device data structure. The kernel will send pointless LPM control
messages to the no longer connected device address and can even cause
several 5 second khubd stalls on some (buggy?) host controllers, before
finally accepting the device's fate amongst a flurry of error messages.

This patch makes the choice of reset dependent on the port status that
has just been read from the hub in addition to the existence of an
in-kernel data structure for the device, and only proceeds with the more
extensive reset if both are valid.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
usb: xhci: add missing dma-mapping.h includes

A randconfig build hit the following build errors because xhci.c and
xhci-mem.c use dma mapping functions but don't include
<linux/dma-mapping.h>. Add the missing includes to fix the build errors.

drivers/usb/host/xhci.c In function 'xhci_gen_setup':
drivers/usb/host/xhci.c +4872 : error: implicit declaration of function 'dma_set_mask'
drivers/usb/host/xhci.c +4872 : error: implicit declaration of function 'DMA_BIT_MASK'

drivers/usb/host/xhci-mem.c In function 'xhci_free_stream_ctx':
drivers/usb/host/xhci-mem.c +435 : error: implicit declaration of function 'dma_free_coherent'
drivers/usb/host/xhci-mem.c In function 'xhci_alloc_stream_ctx':
drivers/usb/host/xhci-mem.c +463 : error: implicit declaration of function 'dma_alloc_coherent'

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
[SCSI] megaraid_sas: megaraid_sas driver init fails in kdump kernel

Problem: When Hardware IOMMU is on, megaraid_sas driver initialization fails
in kdump kernel with LSI MegaRAID controller(device id-0x73).

Actually this issue needs fix in firmware, but for firmware running in field,
this driver fix is proposed to resolve the issue.  At firmware initialization
time, if firmware does not come to ready state, driver will reset the adapter
and retry for firmware transition to ready state unconditionally(not only
executed for kdump kernel).

Signed-off-by: Sumit Saxena <sumit.saxena@lsi.com>
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
[SCSI] fnic: BUG: sleeping function called from invalid context during probe

I hit this during driver probe with the latest fnic updates (this trace
is from a backport into a distro kernel, but the issue is the same).

> BUG: sleeping function called from invalid context at mm/slab.c:3113
> in_atomic(): 0, irqs_disabled(): 1, pid: 610, name: work_for_cpu
> INFO: lockdep is turned off.
> irq event stamp: 0
> hardirqs last  enabled at (0): [<(null)>] (null)
> hardirqs last disabled at (0): [<ffffffff81070aa5>]
> copy_process+0x5e5/0x1670
> softirqs last  enabled at (0): [<ffffffff81070aa5>]
> copy_process+0x5e5/0x1670
> softirqs last disabled at (0): [<(null)>] (null)
> Pid: 610, comm: work_for_cpu Not tainted
> Call Trace:
>  [<ffffffff810b2d10>] ? print_irqtrace_events+0xd0/0xe0
>  [<ffffffff8105c1a7>] ? __might_sleep+0xf7/0x130
>  [<ffffffff81184efb>] ? kmem_cache_alloc_trace+0x20b/0x2d0
>  [<ffffffff8109709e>] ? __create_workqueue_key+0x3e/0x1d0
>  [<ffffffff8109709e>] ? __create_workqueue_key+0x3e/0x1d0
>  [<ffffffffa00c101c>] ? fnic_probe+0x977/0x11aa [fnic]
>  [<ffffffffa00c1048>] ? fnic_probe+0x9a3/0x11aa [fnic]
>  [<ffffffff81096f00>] ? do_work_for_cpu+0x0/0x30
>  [<ffffffff812c6da7>] ? local_pci_probe+0x17/0x20
>  [<ffffffff81096f18>] ? do_work_for_cpu+0x18/0x30
>  [<ffffffff8109cdc6>] ? kthread+0x96/0xa0
>  [<ffffffff8100c1ca>] ? child_rip+0xa/0x20
>  [<ffffffff81550f80>] ? _spin_unlock_irq+0x30/0x40
>  [<ffffffff8100bb10>] ? restore_args+0x0/0x30
>  [<ffffffff8109cd30>] ? kthread+0x0/0xa0
>  [<ffffffff8100c1c0>] ? child_rip+0x0/0x20

The problem is in this hunk of "FIP VLAN Discovery Feature Support"
(d3c995f1dcf938f1084388d92b8fb97bec366566)

create_singlethreaded_workqueue cannot be called with irqs disabled

@@ -620,7 +634,29 @@ static int __devinit fnic_probe(struct pci_dev
*pdev,
        vnic_dev_packet_filter(fnic->vdev, 1, 1, 0, 0, 0);
        vnic_dev_add_addr(fnic->vdev, FIP_ALL_ENODE_MACS);
        vnic_dev_add_addr(fnic->vdev, fnic->ctlr.ctl_src_addr);
+       fnic->set_vlan = fnic_set_vlan;
        fcoe_ctlr_init(&fnic->ctlr, FIP_MODE_AUTO);
+       setup_timer(&fnic->fip_timer, fnic_fip_notify_timer,
+                           (unsigned long)fnic);
+       spin_lock_init(&fnic->vlans_lock);
+       INIT_WORK(&fnic->fip_frame_work, fnic_handle_fip_frame);
+       INIT_WORK(&fnic->event_work, fnic_handle_event);
+       skb_queue_head_init(&fnic->fip_frame_queue);
+       spin_lock_irqsave(&fnic_list_lock, flags);
+       if (!fnic_fip_queue) {
+           fnic_fip_queue =
+               create_singlethread_workqueue("fnic_fip_q");
+           if (!fnic_fip_queue) {
+               spin_unlock_irqrestore(&fnic_list_lock, flags);
+               printk(KERN_ERR PFX "fnic FIP work queue "
+                        "create failed\n");
+               err = -ENOMEM;
+               goto err_out_free_max_pool;
+           }
+       }
+       spin_unlock_irqrestore(&fnic_list_lock, flags);
+       INIT_LIST_HEAD(&fnic->evlist);
+       INIT_LIST_HEAD(&fnic->vlans);
    } else {
        shost_printk(KERN_INFO, fnic->lport->host,
                 "firmware uses non-FIP mode\n");

The attempts to make fnic_fip_queue a single instance for the driver
while it's being created in probe look awkward anyway, why is this not
created in fnic_init_module like the event workqueue?

Signed-off-by: Chris Leech <cleech@redhat.com>
Tested-by: Anantha Tungarakodi <atungara@cisco.com>
Acked-by: Hiral Patel <hiralpat@cisco.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
[SCSI] Don't attempt to send extended INQUIRY command if skip_vpd_pages is set

If a device has the skip_vpd_pages flag set we should simply fail the
scsi_get_vpd_page() call.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Stuart Foster <smf.linux@ntlworld.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Merge tag 'for-usb-linus-2013-07-31' of git://git.kernel.org/pub/scm/linux/kernel/git/sarah/xhci into usb-linus

Sarah writes:

xhci: Misc bug fixes for 3.11.

Hi Greg,

Here's two small fixes for 3.11.  The first patch fixes a 5 second hang in
khubd after a USB device disconnect on some xHCI hosts.  The second fixes a
build warning.

Sarah Sharp
MAINTAINERS: Add separate section for USB NETWORKING DRIVERS

There are several drivers in drivers/net/usb/ that
do not have specific MAINTAINERS that should have
emails forwarded to the linux-usb mailing list.

Add a section for those drivers.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge tag 'iio-fixes-for-3.11b' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus

Jonathan writes:

Second round of IIO fixes for the 3.11 cycle.

1) Fix a long term race in the IIO trigger handling.
   This only effects cases where a single trigger is in use
   by multiple devices.
2) ti_am335x fix an issue with incorrect data due to reading before
   the sequencer is finished.
i2c: i2c-mxs: Use DMA mode even for small transfers

Recently we have been seing some reports about PIO mode not working properly.

- http://www.spinics.net/lists/linux-i2c/msg11985.html
- http://marc.info/?l=linux-i2c&m=137235593101385&w=2
- https://lkml.org/lkml/2013/6/24/430

Let's use DMA mode even for small transfers.

Without this patch, i2c reads the incorrect sgtl5000 version on a mx28evk when
touchscreen is enabled:

[    5.856270] sgtl5000 0-000a: Device with ID register 0 is not a sgtl5000
[    9.877307] sgtl5000 0-000a: ASoC: failed to probe CODEC -19
[    9.883528] mxs-sgtl5000 sound.12: ASoC: failed to instantiate card -19
[    9.892955] mxs-sgtl5000 sound.12: snd_soc_register_card failed (-19)

Cc: <stable@vger.kernel.org>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Marek Vasut <marex@denx.de>

[wsa: we have a proper solution for -next, so this non intrusive
solution is OK for now]

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
i2c: Fix Kontron PLD prescaler calculation

Add some necessary braces that have been removed during driver cleanup.
This fixes the I2C prescaler calculation.

Signed-off-by: Michael Brunner <michael.brunner@kontron.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
LOCKD: Don't call utsname()->nodename from nlmclnt_setlockargs

Firstly, nlmclnt_setlockargs can be called from a reclaimer thread, in
which case we're in entirely the wrong namespace.

Secondly, commit 8aac62706adaaf0fab02c4327761561c8bda9448 (move
exit_task_namespaces() outside of exit_notify()) now means that
exit_task_work() is called after exit_task_namespaces(), which
triggers an Oops when we're freeing up the locks.

Fix this by ensuring that we initialise the nlm_host's rpc_client at mount
time, so that the cl_nodename field is initialised to the value of
utsname()->nodename that the net namespace uses. Then replace the
lockd callers of utsname()->nodename.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Toralf Förster <toralf.foerster@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Nix <nix@esperi.org.uk>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: stable@vger.kernel.org # 3.10.x
SUNRPC: Don't auto-disconnect from the local rpcbind socket

There is no need for the kernel to time out the AF_LOCAL connection to
the rpcbind socket, and doing so is problematic because when it is
time to reconnect, our process may no longer be using the same mount
namespace.

Reported-by: Nix <nix@esperi.org.uk>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: stable@vger.kernel.org # 3.9.x
ALSA: 6fire: fix DMA issues with URB transfer_buffer usage

Patch fixes 6fire not to use stack as URB transfer_buffer. URB buffers need to
be DMA-able, which stack is not. Furthermore, transfer_buffer should not be
allocated as part of larger device structure because DMA coherency issues and
patch fixes this issue too.

Cc: stable@vger.kernel.org
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Tested-by: Torsten Schenk <torsten.schenk@zoho.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
i2c: mv64xxx: Document the newly introduced allwinner compatible

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
nfsd4: Fix MACH_CRED NULL dereference

Fixes a NULL-dereference on attempts to use MACH_CRED protection over
auth_sys.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>