Signed-off-by: David Ward <david.ward@ll.mit.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>

A parameter set exists for WRED mode, called wred_set, to hold the same
values for qavg and qidlestart across all VQs. The WRED mode values had
been previously held in the VQ for the default DP. After these values
were moved to wred_set, the VQ for the default DP was no longer created
automatically (so that it could be omitted on purpose, to have packets
in the default DP enqueued directly to the device without using RED).

However, gred_dump() was overlooked during that change; in WRED mode it
still reads qavg/qidlestart from the VQ for the default DP, which might
not even exist. As a result, this command sequence will cause an oops:

tc qdisc add dev $DEV handle $HANDLE parent $PARENT gred setup \
    DPs 3 default 2 grio
tc qdisc change dev $DEV handle $HANDLE gred DP 0 prio 8 $RED_OPTIONS
tc qdisc change dev $DEV handle $HANDLE gred DP 1 prio 8 $RED_OPTIONS

This fixes gred_dump() in WRED mode to use the values held in wred_set.
Signed-off-by: David Ward <david.ward@ll.mit.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>

If either call to pcan_usb_pro_send_req() in
drivers/net/can/usb/peak_usb/pcan_usb_pro.c::pcan_usb_pro_init()
fails, we'll leak the memory we allocated to 'usb_if' with kzalloc()
when the 'usb_if' variable goes out of scope without having been
assigned to anything as we 'return err;'.
Fix this by adding appropriate kfree(usb_if) calls to the error paths.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Stephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

At the beginning of ks_rcv(), a for loop retrieves the
header information relevant to all the frames stored
in the mac's internal buffers. The number of pending
frames is stored as an 8 bits field in KS_RXFCTR.
If interrupts are disabled long enough to allow for more than
32 frames to accumulate in the MAC's internal buffers, a buffer
overflow occurs.
This patch fixes the problem by making the
driver's frame_head_info buffer big enough.
Well actually, since the chip appears to have 12K of
internal rx buffers and the shortest ethernet frame should
be 64 bytes long, maybe the limit could be set to
12*1024/64 = 192 frames, but 255 should be safer.
Signed-off-by: Davide Ciminaghi <ciminaghi@gnudd.com>
Signed-off-by: Raffaele Recalcati <raffaele.recalcati@bticino.it>
Signed-off-by: David S. Miller <davem@davemloft.net>

There are times we turn of the laser before shutdown.  This is a bad thing
if we want to wake on lan to work so now we make sure the laser is on
before shutdown if we support WoL.
Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com>
Tested-by: Stephen Ko <stephen.s.ko@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

A workaround was previously put in the driver to reset the device when
transitioning to Sx in order to activate the changed settings of the PHY
OEM bits (Low Power Link Up, or LPLU, and GbE disable configuration) for
82577/8/9 devices.  After further review, it was found such a reset can
cause the 82579 to confuse which version of 82579 it actually is and broke
LPLU on all 82577/8/9 devices.  The workaround during an S0->Sx transition
on 82579 (instead of resetting the PHY) is to restart auto-negotiation
after the OEM bits are configured; the restart of auto-negotiation
activates the new OEM bits as does the reset.  With 82577/8, the reset is
changed to a generic reset which fixes the LPLU bits getting set wrong.
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

The SMSC911x driver resets the ->head, ->data and ->tail pointers in the
skb on the reset path in order to avoid buffer overflow due to packet
padding performed by the hardware.

This patch fixes the receive path so that the skb pointers are fixed up
after the data has been read from the device, The error path is also
fixed to use number of words consistently and prevent erroneous FIFO
fastforwarding when skipping over bad data.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Move the ks8851_rdreg16 call above the call to request_irq and cache
the result for subsequent repeated use.  A spurious interrupt may
otherwise cause a crash.  Thanks to Stephen Boyd, Flavio Leitner, and
Ben Hutchings for feedback.
Signed-off-by: Matt Renzelmann <mjr@cs.wisc.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>

Also fix MAINTAINERS file to reflect autorship.

Daniel and Ariane changed coding style but not any functional changes in the driver
itself.
Signed-off-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

We set intr mask before its handler is registered, this does not work well when
8139cp is sharing irq line with other devices. As the irq could be enabled by
the device before 8139cp's hander is registered which may lead unhandled
irq. Fix this by introducing an helper cp_irq_enable() and call it after
request_irq().
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Problem:
There was two separate work_struct structures which share one
handler. Unfortunately getting atl1_adapter structure from
work_struct in case of DMA error was done from incorrect
offset which cause kernel panics.

Solution:
The useless work_struct for DMA error removed and
handler name changed to more generic one.
Signed-off-by: Tony Zelenoff <antonz@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The skb struct ubuf_info callback gets passed struct ubuf_info
itself, not the arg value as the field name and the function signature
seem to imply. Rename the arg field to ctx to match usage,
add documentation and change the callback argument type
to make usage clear and to have compiler check correctness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit e675f0cc ("ppp: Don't stop and
restart queue on every TX packet") introduced a race condition which
could leave the net queue stopped even when the channel is no longer
busy. By calling netif_stop_queue() from ppp_start_xmit(), based on the
return value from ppp_xmit_process() but *after* all the locks have been
dropped, we could potentially do so *after* the channel has actually
finished transmitting and attempted to re-wake the queue.

Fix this by moving the netif_stop_queue() into ppp_xmit_process() under
the xmit lock. I hadn't done this previously, because it gets called
from other places than ppp_start_xmit(). But I now think it's the better
option. The net queue *should* be stopped if the channel becomes
congested due to writes from pppd, anyway.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If the ipv6 dst cache which copy from the dst generated by ICMPV6 RA packet.
this dst cache will not check expire because it has no RTF_EXPIRES flag.
So this dst cache will always be used until the dst gc run.

Change the struct dst_entry,add a union contains new pointer from and expires.
When rt6_info.rt6i_flags has no RTF_EXPIRES flag,the dst.expires has no use.
we can use this field to point to where the dst cache copy from.
The dst.from is only used in IPV6.

rt6_check_expired check if rt6_info.dst.from is expired.

ip6_rt_copy only set dst.from when the ort has flag RTF_ADDRCONF
and RTF_DEFAULT.then hold the ort.

ip6_dst_destroy release the ort.

Add some functions to operate the RTF_EXPIRES flag and expires(from) together.
and change the code to use these new adding functions.

Changes from v5:
modify ip6_route_add and ndisc_router_discovery to use new adding functions.

Only set dst.from when the ort has flag RTF_ADDRCONF
and RTF_DEFAULT.then hold the ort.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use dev_dbg instead of dev_err for reporting in cfhsi_wakeup_cb.
Signed-off-by: Kim Lilliestierna <kim.xx.lilliestierna@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix memory leak of RX flip-buffer.
Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Added kfree_skb() calls in the chnk_net.c file on
the error paths.
Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Applications using L2TP/IP sockets want to be able to bind() an L2TP/IP
socket to set the local tunnel id while leaving the auto-assigned source
address alone. So if no source address is supplied, don't overwrite
the address already stored in the socket.
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The l2tp_ip socket close handler does not update the module refcount
correctly which prevents module unload after the first bind() call on
an L2TPv3 IP encapulation socket.
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit 2e57b79c misplaced its
parenthesis and now tx_fifo_errors will only be incremented if an
ENOMEM error is not written to the syslog.

Correct the parenthesis and indentation to the original goal of
counting all non ENOMEM errors and ratelimiting only the messages.
Signed-of-by: Torsten Kaiser <just.for.lkml@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

At the point of this error-handling code, alloc_skb has succeded, so free
the resulting skb by jumping to the err label.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

Recently an oops was reported in phonet if there was a failure during
network namespace creation.

[  163.733755] ------------[ cut here ]------------
[  163.734501] kernel BUG at include/net/netns/generic.h:45!
[  163.734501] invalid opcode: 0000 [#1] PREEMPT SMP
[  163.734501] CPU 2
[  163.734501] Pid: 19145, comm: trinity Tainted: G        W 3.4.0-rc1-next-20120405-sasha-dirty #57
[  163.734501] RIP: 0010:[<ffffffff824d6062>]  [<ffffffff824d6062>] phonet_pernet+0x182/0x1a0
[  163.734501] RSP: 0018:ffff8800674d5ca8  EFLAGS: 00010246
[  163.734501] RAX: 000000003fffffff RBX: 0000000000000000 RCX: ffff8800678c88d8
[  163.734501] RDX: 00000000003f4000 RSI: ffff8800678c8910 RDI: 0000000000000282
[  163.734501] RBP: ffff8800674d5cc8 R08: 0000000000000000 R09: 0000000000000000
[  163.734501] R10: 0000000000000000 R11: 0000000000000000 R12: ffff880068bec920
[  163.734501] R13: ffffffff836b90c0 R14: 0000000000000000 R15: 0000000000000000
[  163.734501] FS:  00007f055e8de700(0000) GS:ffff88007d000000(0000) knlGS:0000000000000000
[  163.734501] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  163.734501] CR2: 00007f055e6bb518 CR3: 0000000070c16000 CR4: 00000000000406e0
[  163.734501] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  163.734501] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  163.734501] Process trinity (pid: 19145, threadinfo ffff8800674d4000, task ffff8800678c8000)
[  163.734501] Stack:
[  163.734501]  ffffffff824d5f00 ffffffff810e2ec1 ffff880067ae0000 00000000ffffffd4
[  163.734501]  ffff8800674d5cf8 ffffffff824d667a ffff880067ae0000 00000000ffffffd4
[  163.734501]  ffffffff836b90c0 0000000000000000 ffff8800674d5d18 ffffffff824d707d
[  163.734501] Call Trace:
[  163.734501]  [<ffffffff824d5f00>] ? phonet_pernet+0x20/0x1a0
[  163.734501]  [<ffffffff810e2ec1>] ? get_parent_ip+0x11/0x50
[  163.734501]  [<ffffffff824d667a>] phonet_device_destroy+0x1a/0x100
[  163.734501]  [<ffffffff824d707d>] phonet_device_notify+0x3d/0x50
[  163.734501]  [<ffffffff810dd96e>] notifier_call_chain+0xee/0x130
[  163.734501]  [<ffffffff810dd9d1>] raw_notifier_call_chain+0x11/0x20
[  163.734501]  [<ffffffff821cce12>] call_netdevice_notifiers+0x52/0x60
[  163.734501]  [<ffffffff821cd235>] rollback_registered_many+0x185/0x270
[  163.734501]  [<ffffffff821cd334>] unregister_netdevice_many+0x14/0x60
[  163.734501]  [<ffffffff823123e3>] ipip_exit_net+0x1b3/0x1d0
[  163.734501]  [<ffffffff82312230>] ? ipip_rcv+0x420/0x420
[  163.734501]  [<ffffffff821c8515>] ops_exit_list+0x35/0x70
[  163.734501]  [<ffffffff821c911b>] setup_net+0xab/0xe0
[  163.734501]  [<ffffffff821c9416>] copy_net_ns+0x76/0x100
[  163.734501]  [<ffffffff810dc92b>] create_new_namespaces+0xfb/0x190
[  163.734501]  [<ffffffff810dca21>] unshare_nsproxy_namespaces+0x61/0x80
[  163.734501]  [<ffffffff810afd1f>] sys_unshare+0xff/0x290
[  163.734501]  [<ffffffff8187622e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[  163.734501]  [<ffffffff82665539>] system_call_fastpath+0x16/0x1b
[  163.734501] Code: e0 c3 fe 66 0f 1f 44 00 00 48 c7 c2 40 60 4d 82 be 01 00 00 00 48 c7 c7 80 d1 23 83 e8 48 2a c4 fe e8 73 06 c8 fe 48 85 db 75 0e <0f> 0b 0f 1f 40 00 eb fe 66 0f 1f 44 00 00 48 83 c4 10 48 89 d8
[  163.734501] RIP  [<ffffffff824d6062>] phonet_pernet+0x182/0x1a0
[  163.734501]  RSP <ffff8800674d5ca8>
[  163.861289] ---[ end trace fb5615826c548066 ]---

After investigation it turns out there were two issues.
1) Phonet was not implementing network devices but was using register_pernet_device
   instead of register_pernet_subsys.

   This was allowing there to be cases when phonenet was not initialized and
   the phonet net_generic was not set for a network namespace when network
   device events were being reported on the netdevice_notifier for a network
   namespace leading to the oops above.

2) phonet_exit_net was implementing a confusing and special case of handling all
   network devices from going away that it was hard to see was correct, and would
   only occur when the phonet module was removed.

   Now that unregister_netdevice_notifier has been modified to synthesize unregistration
   events for the network devices that are extant when called this confusing special
   case in phonet_exit_net is no longer needed.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We already synthesize events in register_netdevice_notifier and synthesizing
events in unregister_netdevice_notifier allows to us remove the need for
special case cleanup code.

This change should be safe as it adds no new cases for existing callers
of unregiser_netdevice_notifier to handle.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Merge fixes from Andrew Morton.

* emailed from Andrew Morton <akpm@linux-foundation.org>: (14 patches)
  panic: fix stack dump print on direct call to panic()
  drivers/rtc/rtc-pl031.c: enable clock on all ST variants
  Revert "mm: vmscan: fix misused nr_reclaimed in shrink_mem_cgroup_zone()"
  hugetlb: fix race condition in hugetlb_fault()
  drivers/rtc/rtc-twl.c: use static register while reading time
  drivers/rtc/rtc-s3c.c: add placeholder for driver private data
  drivers/rtc/rtc-s3c.c: fix compilation error
  MAINTAINERS: add PCDP console maintainer
  memcg: do not open code accesses to res_counter members
  drivers/rtc/rtc-efi.c: fix section mismatch warning
  drivers/rtc/rtc-r9701.c: reset registers if invalid values are detected
  drivers/char/random.c: fix boot id uniqueness race
  memcg: fix broken boolen expression
  memcg: fix up documentation on global LRU

Pull networking fixes from David Miller:

 1) Fix bluetooth userland regression reported by Keith Packard, from
    Gustavo Padovan.

 2) Revert ath9k PS idle change, from Sujith Manoharan.

 3) Correct default TCP memory limits (again), from Eric Dumazet.

 4) Fix tcp_rcv_rtt_update() accidental use of unscaled RTT, from Neal
    Cardwell.

 5) We made a facility for layers like wireless to say how much tailroom
    they need in the SKB for link layer stuff such as wireless
    encryption etc., but TCP works hard to fill every SKB out to the end
    defeating this specification.

    This leads to every TCP packet getting reallocated by the wireless
    code in order to have the right amount of tailroom available.

    Fix TCP to only fill SKBs out to the real amount of data area it
    asked for during the allocation, this way it won't eat into the
    slack added for the device's tailroom needs.

    Reported by Marc Merlin and fixed by Eric Dumazet.

 6) Leaks, endian bugs, and new device IDs in bluetooth from Santosh
    Nayak, João Paulo Rechi Vita, Cho, Yu-Chen, Andrei Emeltchenko,
    AceLan Kao, and Andrei Emeltchenko.

 7) OOPS on tty_close fix in bluetooth's hci_ldisc from Johan Hovold.

 8) netfilter erroneously scales TCP window twice, fix from Changli Gao.

 9) Memleak fix in wext-core from Julia Lawall.

10) Consistently handle invalid TCP packets in ipv4 vs.  ipv6 conntrack,
    from Jozsef Kadlecsik.

11) Validate IP header length properly in netfilter conntrack's
    ipv4_get_l4proto().

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (39 commits)
  NFC: Fix the LLCP Tx fragmentation loop
  rtlwifi: Add missing DMA buffer unmapping for PCI drivers
  rtlwifi: Preallocate USB read buffers and eliminate kalloc in read routine
  tcp: avoid order-1 allocations on wifi and tx path
  net: allow pskb_expand_head() to get maximum tailroom
  bridge: Do not send queries on multicast group leaves
  MAINTAINERS: Mark NATSEMI driver as orphan'd.
  tcp: fix tcp_rcv_rtt_update() use of an unscaled RTT sample
  tcp: restore correct limit
  Revert "ath9k: fix going to full-sleep on PS idle"
  rt2x00: Fix rfkill_polling register function.
  bcma: fix build error on MIPS; implicit pcibios_enable_device
  netfilter: nf_conntrack: fix incorrect logic in nf_conntrack_init_net
  netfilter: nf_ct_ipv4: packets with wrong ihl are invalid
  netfilter: nf_ct_ipv4: handle invalid IPv4 and IPv6 packets consistently
  net/wireless/wext-core.c: add missing kfree
  rtlwifi: Fix oops on rate-control failure
  mac80211: Convert WARN_ON to WARN_ON_ONCE
  rtlwifi: rtl8192de: Fix firmware initialization
  nl80211: ensure interface is up in various APIs
  ...

Pull drm fixes from Dave Airlie:
 "Mostly exynos and intel.

  Intel has 3 regression fixers (more info in intel merge commit), along
  with some other make hw work fixes, exynos has some cleanups and an
  ioctl fix.

  A couple of radeon fixes, couple of build fixes, and a savage
  userspace interface possible overflow fix."

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (23 commits)
  drm/exynos: fixed exynos broken ioctl
  drm/i915: clear fencing tracking state when retiring requests
  drm/exynos: fix to pointer manager member of struct exynos_drm_subdrv
  drm/exynos: fix struct for operation callback functions to driver name
  drm/exynos: use define instead of default_win member in struct mixer_context
  drm/exynos: rename s/HDMI_OVERLAY_NUMBER/MIXER_WIN_NR
  drm/exynos: remove unused codes in hdmi and mixer
  drm/exynos: remove unnecessary type conversion of hdmi and mixer
  drm/i915: make rc6 module parameter read-only
  drm/i915: implement ColorBlt w/a
  drm/i915/ringbuffer: Exclude last 2 cachlines of ring on 845g
  Revert "drm/i915: reenable gmbus on gen3+ again"
  drm/radeon: only add the mm i2c bus if the hw_i2c module param is set
  vgaarb.h: fix build warnings
  drm/i915: properly compute dp dithering for user-created modes
  drm/radeon/kms: fix DVO setup on some r4xx chips
  drm/savage: fix integer overflows in savage_bci_cmdbuf()
  drm/radeon: replace udelay with mdelay for long timeouts
  drm/i915: Finish any pending operations on the framebuffer before disabling
  drm/i915: Removed IVB forced enable of sprite dest key.
  ...

Pull a few more fixes for md from NeilBrown:
 "Two are tagged for -stable.  They can cause an oops, but very rarely."

* tag 'md-3.4-fixes' of git://neil.brown.name/md:
  md/bitmap: prevent bitmap_daemon_work running while initialising bitmap
  md/raid1,raid10: Fix calculation of 'vcnt' when processing error recovery.
  MD: Bitmap version cleanup.

Commit 6e6f0a1f ("panic: don't print redundant backtraces on oops")
causes a regression where no stack trace will be printed at all for the
case where kernel code calls panic() directly while not processing an
oops, and of course there are 100's of instances of this type of call.

The original commit executed the check (!oops_in_progress), but this will
always be false because just before the dump_stack() there is a call to
bust_spinlocks(1), which does the following:

  void __attribute__((weak)) bust_spinlocks(int yes)
  {
	if (yes) {
		++oops_in_progress;

The proper way to resolve the problem that original commit tried to
solve is to avoid printing a stack dump from panic() when the either of
the following conditions is true:

  1) TAINT_DIE has been set (this is done by oops_end())
     This indicates and oops has already been printed.
  2) oops_in_progress > 1
     This guards against the rare case where panic() is invoked
     a second time, or in between oops_begin() and oops_end()
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: <stable@vger.kernel.org>	[3.3+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The ST variants of the PL031 all require bit 26 in the control register
to be set before they work properly.  Discovered this when testing on
the Nomadik board where it would suprisingly just stand still.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
Cc: Alessandro Rubini <rubini@unipv.it>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This reverts commit c38446cc.

Before the commit, the code makes senses to me but not after the commit.
The "nr_reclaimed" is the number of pages reclaimed by scanning through
the memcg's lru lists.  The "nr_to_reclaim" is the target value for the
whole function.  For example, we like to early break the reclaim if
reclaimed 32 pages under direct reclaim (not DEF_PRIORITY).

After the reverted commit, the target "nr_to_reclaim" is decremented each
time by "nr_reclaimed" but we still use it to compare the "nr_reclaimed".
It just doesn't make sense to me...
Signed-off-by: Ying Han <yinghan@google.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The race is as follows:

Suppose a multi-threaded task forks a new process (on cpu A), thus
bumping up the ref count on all the pages.  While the fork is occurring
(and thus we have marked all the PTEs as read-only), another thread in
the original process (on cpu B) tries to write to a huge page, taking an
access violation from the write-protect and calling hugetlb_cow().  Now,
suppose the fork() fails.  It will undo the COW and decrement the ref
count on the pages, so the ref count on the huge page drops back to 1.
Meanwhile hugetlb_cow() also decrements the ref count by one on the
original page, since the original address space doesn't need it any
more, having copied a new page to replace the original page.  This
leaves the ref count at zero, and when we call unlock_page(), we panic.

	fork on CPU A				fault on CPU B
	=============				==============
	...
	down_write(&parent->mmap_sem);
	down_write_nested(&child->mmap_sem);
	...
	while duplicating vmas
		if error
			break;
	...
	up_write(&child->mmap_sem);
	up_write(&parent->mmap_sem);		...
						down_read(&parent->mmap_sem);
						...
						lock_page(page);
						handle COW
						page_mapcount(old_page) == 2
						alloc and prepare new_page
	...
	handle error
	page_remove_rmap(page);
	put_page(page);
	...
						fold new_page into pte
						page_remove_rmap(page);
						put_page(page);
						...
				oops ==>	unlock_page(page);
						up_read(&parent->mmap_sem);

The solution is to take an extra reference to the page while we are
holding the lock on it.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

RTC stores time and date in several registers.  Due to the fact that
these registers can't be read instantaneously, there is a chance that
reading from counting registers gives an error of one minute, one hour,
one day, etc.

To address this issue, the RTC has hardware support to copy the RTC
counting registers to static shadowed registers.  The current
implementation does not use this feature, and in a stress test, we can
reproduce this error at a rate of around two times per 300000 readings.

Fix the implementation to ensure that the right snapshot of time is
captured.
Signed-off-by: Konstantin Shlyakhovoy <x0155534@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: linux-omap <linux-omap@vger.kernel.org>
Acked-by: Mykola Oleksiienko <x0174904@ti.com>
Acked-by: Oleksandr Dmytryshyn <oleksandr.dmytryshyn@ti.com>
Acked-by: Graeme Gregory <gg@slimlogic.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Driver data field is a pointer, hence assigning that to an integer results
in compilation warnings.

Fixes following compilation warnings:

  drivers/rtc/rtc-s3c.c: In function `s3c_rtc_get_driver_data':
  drivers/rtc/rtc-s3c.c:452:3: warning: return makes integer from pointer without a cast [enabled by default]
  drivers/rtc/rtc-s3c.c: At top level:
  drivers/rtc/rtc-s3c.c:674:3: warning: initialization makes pointer from integer without a cast [enabled by default]
  drivers/rtc/rtc-s3c.c:674:3: warning: (near initialization for `s3c_rtc_dt_match[1].data') [enabled by default]
  drivers/rtc/rtc-s3c.c:677:3: warning: initialization makes pointer from integer without a cast [enabled by default]
  drivers/rtc/rtc-s3c.c:677:3: warning: (near initialization for `s3c_rtc_dt_match[2].data') [enabled by default]
  drivers/rtc/rtc-s3c.c:680:3: warning: initialization makes pointer from integer without a cast [enabled by default]
  drivers/rtc/rtc-s3c.c:680:3: warning: (near initialization for `s3c_rtc_dt_match[3].data') [enabled by default]
Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix this error:

  drivers/rtc/rtc-s3c.c: At top level:
  drivers/rtc/rtc-s3c.c:671:3: error: request for member `data' in something not a structure or union
  drivers/rtc/rtc-s3c.c:674:3: error: request for member `data' in something not a structure or union
  drivers/rtc/rtc-s3c.c:677:3: error: request for member `data' in something not a structure or union
  drivers/rtc/rtc-s3c.c:680:3: error: request for member `data' in something not a structure or union
Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add missing maintainer info for PCDP console code.
Signed-off-by: Khalid Aziz <khalid.aziz@hp.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We should use the accessor res_counter_read_u64 for that.

Although a purely cosmetic change is sometimes better delayed, to avoid
conflicting with other people's work, we are starting to have people
touching this code as well, and reproducing the open code behavior
because that's the standard =)

Time to fix it, then.
Signed-off-by: Glauber Costa <glommer@parallels.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

efi_rtc_init() uses platform_driver_probe(), so there's no need to also
set efi_rtc_driver's probe member (as it won't be used anyway).  This
fixes a modpost section mismatch warning (as efi_rtc_probe() validly is
__init).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hwclock refuses to set date/time if RTC registers contain invalid
values.  Check the date/time register values at probe time and
initialize them to make hwclock happy.
Signed-off-by: Andreas Dumberger <andreas.dumberger@tqs.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

/proc/sys/kernel/random/boot_id can be read concurrently by userspace
processes.  If two (or more) user-space processes concurrently read
boot_id when sysctl_bootid is not yet assigned, a race can occur making
boot_id differ between the reads.  Because the whole point of the boot id
is to be unique across a kernel execution, fix this by protecting this
operation with a spinlock.

Given that this operation is not frequently used, hitting the spinlock
on each call should not be an issue.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

action != CPU_DEAD || action != CPU_DEAD_FROZEN is always true.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>