commit cab46214 upstream.

With an RTL8191SU USB adaptor, sometimes the hints for a fragmented
packet are set, but the packet length is too large. Allocate enough
space to prevent memory corruption and a resulting kernel panic [1].

[1] http://www.spinics.net/lists/linux-wireless/msg136546.htmlSigned-off-by: Haggai Eran <haggai.eran@gmail.com>
ACKed-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit e5babdf9 upstream.

Since commit bd31b859 (which is in 3.2-rc1) nw_gpio_lock is a raw spinlock
that needs usage of the corresponding raw functions.

This fixes:

  drivers/mtd/maps/dc21285.c: In function 'nw_en_write':
  drivers/mtd/maps/dc21285.c:41:340: warning: passing argument 1 of 'spinlock_check' from incompatible pointer type
    spin_lock_irqsave(&nw_gpio_lock, flags);

  In file included from include/linux/seqlock.h:35:0,
                   from include/linux/time.h:5,
                   from include/linux/stat.h:18,
                   from include/linux/module.h:10,
                   from drivers/mtd/maps/dc21285.c:8:
  include/linux/spinlock.h:299:102: note: expected 'struct spinlock_t *' but argument is of type 'struct raw_spinlock_t *'
   static inline raw_spinlock_t *spinlock_check(spinlock_t *lock)
                                                                                                        ^
  drivers/mtd/maps/dc21285.c:43:25: warning: passing argument 1 of 'spin_unlock_irqrestore' from incompatible pointer type
    spin_unlock_irqrestore(&nw_gpio_lock, flags);
                           ^
  In file included from include/linux/seqlock.h:35:0,
                   from include/linux/time.h:5,
                   from include/linux/stat.h:18,
                   from include/linux/module.h:10,
                   from drivers/mtd/maps/dc21285.c:8:
  include/linux/spinlock.h:370:91: note: expected 'struct spinlock_t *' but argument is of type 'struct raw_spinlock_t *'
   static inline void spin_unlock_irqrestore(spinlock_t *lock, unsigned long flags)

Fixes: bd31b859 ("locking, ARM: Annotate low level hw locks as raw")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 6e91f8cb upstream.

If, at the time __rcu_process_callbacks() is invoked,  there are callbacks
in Tiny RCU's callback list, but none of them are ready to be invoked,
the current list-management code will knit the non-ready callbacks out
of the list.  This can result in hangs and possibly worse.  This commit
therefore inserts a check for there being no callbacks that can be
invoked immediately.

This bug is unlikely to occur -- you have to get a new callback between
the time rcu_sched_qs() or rcu_bh_qs() was called, but before we get to
__rcu_process_callbacks().  It was detected by the addition of RCU-bh
testing to rcutorture, which in turn was instigated by Iftekhar Ahmed's
mutation testing.  Although this bug was made much more likely by
915e8a4f (rcu: Remove fastpath from __rcu_process_callbacks()), this
did not cause the bug, but rather made it much more probable.   That
said, it takes more than 40 hours of rcutorture testing, on average,
for this bug to appear, so this fix cannot be considered an emergency.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
[bwh: Backported to 3.2: adjust filename, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 76e838c9 upstream.

We need to return error to caller if command is not sent to
controller succesfully.
Signed-off-by: Subbaraya Sundeep Bhatta <sbhatta@xilinx.com>
Fixes: 72246da4 (usb: Introduce DesignWare USB3 DRD Driver)
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 39fa10f7 upstream.

Since we are messing with state in the worker.

v2: drop the changes in the mst worker
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 8687634b upstream.

In RS485 mode, we may want to set the delay_rts_after_send value to 0.
In the datasheet, the 0 value is said to "disable" the Transmitter Timeguard but
this is exactly the expected behavior if we want no delay...

Moreover, if the value was set to non-zero value by device-tree or earlier
ioctl command, it was impossible to change it back to zero.
Reported-by: Sami Pietikäinen <Sami.Pietikainen@wapice.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit d079abd1 upstream.

Too many spaces were introduced in commit 63adc6fb ("pktgen: cleanup
checkpatch warnings"), thus misaligning "src_min:" to other columns.

Fixes: 63adc6fb ("pktgen: cleanup checkpatch warnings")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 12c35005 upstream.

WM8955_K_8_0_MASK bits is controlled by WM8955_PLL_CONTROL_3 rather than
WM8955_PLL_CONTROL_2.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit ebb6ad73 upstream.

VMID Control 0 BIT[2:1] is VMID Divider Enable and Select

00 = VMID disabled (for OFF mode)
01 = 2 x 50kΩ divider (for normal operation)
10 = 2 x 250kΩ divider (for low power standby)
11 = 2 x 5kΩ divider (for fast start-up)

So WM8903_VMID_RES_250K should be 2 << 1, which is 4.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 14ba3ec1 upstream.

According to the datasheet:
R10 (0Ah) VMID Impedance Control

BIT 3:2 VMIDSEL DEFAULT 00

DESCRIPTION: VMID impedance selection control
00: 75kΩ output
01: 300kΩ output
10: 2.5kΩ output

WM8737_VMIDSEL_MASK is 0xC (VMIDSEL - [3:2]),
so it needs to left shift WM8737_VMIDSEL_SHIFT bits for setting these bits.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 5fa7dadc upstream.

Fixes: 1d11911a ("crypto: talitos - fix warning: 'alg' may be used uninitialized in this function")
Signed-off-by: Horia Geanta <horia.geanta@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 073db4a5 upstream.

On A MIPS 32-cores machine a BUG_ON was triggered because some acesses to
mtd->usecount were done without taking mtd_table_mutex.
kernel: Call Trace:
kernel: [<ffffffff80401818>] __put_mtd_device+0x20/0x50
kernel: [<ffffffff804086f4>] blktrans_release+0x8c/0xd8
kernel: [<ffffffff802577e0>] __blkdev_put+0x1a8/0x200
kernel: [<ffffffff802579a4>] blkdev_close+0x1c/0x30
kernel: [<ffffffff8022006c>] __fput+0xac/0x250
kernel: [<ffffffff80171208>] task_work_run+0xd8/0x120
kernel: [<ffffffff8012c23c>] work_notifysig+0x10/0x18
kernel:
kernel:
        Code: 2442ffff  ac8202d8  000217fe <00020336> dc820128  10400003
               00000000  0040f809  00000000
kernel: ---[ end trace 080fbb4579b47a73 ]---

Fixed by taking the mutex in blktrans_open and blktrans_release.

Note that this locking is already suggested in
include/linux/mtd/blktrans.h:

struct mtd_blktrans_ops {
...
	/* Called with mtd_table_mutex held; no race with add/remove */
	int (*open)(struct mtd_blktrans_dev *dev);
	void (*release)(struct mtd_blktrans_dev *dev);
...
};

But we weren't following it.

Originally reported by (and patched by) Zhang and Giuseppe,
independently. Improved and rewritten.
Reported-by: Zhang Xingcai <zhangxingcai@huawei.com>
Reported-by: Giuseppe Cantavenera <giuseppe.cantavenera.ext@nokia.com>
Tested-by: Giuseppe Cantavenera <giuseppe.cantavenera.ext@nokia.com>
Acked-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 1fa2337a upstream.

The maximum size for a DiSEqC command is 6, according to the
userspace API. However, the code allows to write up much more values:
	drivers/media/dvb-frontends/cx24116.c:983 cx24116_send_diseqc_msg() error: buffer overflow 'd->msg' 6 <= 23
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 12f4543f upstream.

The maximum size for a DiSEqC command is 6, according to the
userspace API. However, the code allows to write up to 7 values:
	drivers/media/dvb-frontends/s5h1420.c:193 s5h1420_send_master_cmd() error: buffer overflow 'cmd->msg' 6 <= 7
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 5de2755c upstream.

Because we drop cpu_base->lock around calling hrtimer::function, it is
possible for hrtimer_start() to come in between and enqueue the timer.

If hrtimer::function then returns HRTIMER_RESTART we'll hit the BUG_ON
because HRTIMER_STATE_ENQUEUED will be set.

Since the above is a perfectly valid scenario, remove the BUG_ON and
make the enqueue_hrtimer() call conditional on the timer not being
enqueued already.

NOTE: in that concurrent scenario its entirely common for both sites
to want to modify the hrtimer, since hrtimers don't provide
serialization themselves be sure to provide some such that the
hrtimer::function and the hrtimer_start() caller don't both try and
fudge the expiration state at the same time.

To that effect, add a WARN when someone tries to forward an already
enqueued timer, the most common way to change the expiry of self
restarting timers. Ideally we'd put the WARN in everything modifying
the expiry but most of that is inlines and we don't need the bloat.

Fixes: 2d44ae4d ("hrtimer: clean up cpu->base locking tricks")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Roman Gushchin <klamm@yandex-team.ru>
Cc: Paul Turner <pjt@google.com>
Link: http://lkml.kernel.org/r/20150415113105.GT5029@twins.programming.kicks-ass.netSigned-off-by: Thomas Gleixner <tglx@linutronix.de>
[bwh: Backported to 3.2: adjust filename, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 1d0a0b2f upstream.

ACPICA commit b60612373a4ef63b64a57c124576d7ddb6d8efb6

For physical addresses, since the address may exceed 32-bit address range
after calculation, we should use 0x%8.8X%8.8X instead of ACPI_PRINTF_UINT
and ACPI_FORMAT_UINT64() instead of
ACPI_FORMAT_NATIVE_UINT()/ACPI_FORMAT_TO_UINT().

This patch also removes above replaced macros as there are no users.

This is a preparation to switch acpi_physical_address to 64-bit on 32-bit
kernel builds.

Link: https://github.com/acpica/acpica/commit/b6061237Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
[gdavis: Move tbprint.c changes to tbutils.c due to lack of commit
	 "42f47869 ACPICA: Split table print utilities to a new a
	 separate file" in linux-3.10.y]
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit cc2080b0 upstream.

ACPICA commit 7f06739db43a85083a70371c14141008f20b2198

For physical addresses, since the address may exceed 32-bit address range
after calculation, we should use %8.8X%8.8X (see ACPI_FORMAT_UINT64()) to
convert the %p formats.

This is a preparation to switch acpi_physical_address to 64-bit on 32-bit
kernel builds.

Link: https://github.com/acpica/acpica/commit/7f06739dSigned-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
[gdavis: Move tbinstall.c changes to tbutils.c due to lack of commit
	 "42f47869 ACPICA: Split table print utilities to a new a
	 separate file" in linux-3.10.y]
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2:
 - Drop inapplicable changes to drivers/acpi/acpica/utaddress.c and
   acpi_tb_install_table()
 - Fix similar format issues in acpi_tb_add_table() and
   acpi_tb_install_table() that aren't present upstream]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 0b232fca upstream.

Cleanup output for Processor(). Length is a byte, not a word.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 85e014b4 upstream.

commit f254e3c5 upstream.

ACPICA commit 7d9fd64397d7c38899d3dc497525f6e6b044e0e3

OSPMs like Linux expect an acpi_physical_address returning value from
acpi_find_root_pointer(). This triggers warnings if sizeof (acpi_size) doesn't
equal to sizeof (acpi_physical_address):
  drivers/acpi/osl.c:275:3: warning: passing argument 1 of 'acpi_find_root_pointer' from incompatible pointer type [enabled by default]
  In file included from include/acpi/acpi.h:64:0,
                   from include/linux/acpi.h:36,
                   from drivers/acpi/osl.c:41:
  include/acpi/acpixf.h:433:1: note: expected 'acpi_size *' but argument is of type 'acpi_physical_address *'
This patch corrects acpi_find_root_pointer().

Link: https://github.com/acpica/acpica/commit/7d9fd643Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit d657784b upstream.

Minimal fix to allow leon to be built.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Konrad Eisele <konrad@gaisler.com>
Cc: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 9f613601 upstream.

__sync_fetch_and_and and __sync_fetch_and_or are functions that are provided
by gcc and depending on the target architecture may be implemented in libgcc,
which is not always available in the kernel. This leads to a build failure
on ARMv5:

drivers/built-in.o: In function `line6_pcm_release':
:(.text+0x3bfe80): undefined reference to `__sync_fetch_and_and_4'
drivers/built-in.o: In function `line6_pcm_acquire':
:(.text+0x3bff30): undefined reference to `__sync_fetch_and_or_4'

To work around this, we can use the kernel-provided cmpxchg macro.

Build-tested only.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Markus Grabner <grabner@icg.tugraz.at>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2:
 - Adjust context
 - Fix up two more instances of __sync_fetch_and_and() that were removed
   separately upstream]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit ca0ad83d upstream.

The Debian experimental linux source package (3.8.5-1) build fails
with the following errors:
...
MODPOST 2016 modules
ERROR: "__ucmpdi2" [fs/btrfs/btrfs.ko] undefined!
ERROR: "__ucmpdi2" [drivers/md/dm-verity.ko] undefined!

The attached patch resolves this problem.  It is based on the s390
implementation of ucmpdi2.c.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 9aa272b4 upstream.

Running mtd-utils/tests/ubi-tests/io_basic.c could cause
soft lockup or watchdog reset. It is because *updatevol*
will perform ubi_check_volume() after updating finish
and this function will full scan the updated lebs if the
volume is initialized as STATIC_VOLUME.

This patch adds *cond_resched()* in the loop of lebs scan
to avoid soft lockup.

Helped by Richard Weinberger <richard@nod.at>

[ 2158.067096] INFO: rcu_sched self-detected stall on CPU { 1}  (t=2101 jiffies g=1606 c=1605 q=56)
[ 2158.172867] CPU: 1 PID: 2073 Comm: io_basic Tainted: G           O 3.10.53 #21
[ 2158.172898] [<c000f624>] (unwind_backtrace+0x0/0x120) from [<c000c294>] (show_stack+0x10/0x14)
[ 2158.172918] [<c000c294>] (show_stack+0x10/0x14) from [<c008ac3c>] (rcu_check_callbacks+0x1c0/0x660)
[ 2158.172936] [<c008ac3c>] (rcu_check_callbacks+0x1c0/0x660) from [<c002b480>] (update_process_times+0x38/0x64)
[ 2158.172953] [<c002b480>] (update_process_times+0x38/0x64) from [<c005ff38>] (tick_sched_handle+0x54/0x60)
[ 2158.172966] [<c005ff38>] (tick_sched_handle+0x54/0x60) from [<c00601ac>] (tick_sched_timer+0x44/0x74)
[ 2158.172978] [<c00601ac>] (tick_sched_timer+0x44/0x74) from [<c003f348>] (__run_hrtimer+0xc8/0x1b8)
[ 2158.172992] [<c003f348>] (__run_hrtimer+0xc8/0x1b8) from [<c003fd9c>] (hrtimer_interrupt+0x128/0x2a4)
[ 2158.173007] [<c003fd9c>] (hrtimer_interrupt+0x128/0x2a4) from [<c0246f1c>] (arch_timer_handler_virt+0x28/0x30)
[ 2158.173022] [<c0246f1c>] (arch_timer_handler_virt+0x28/0x30) from [<c0086214>] (handle_percpu_devid_irq+0x9c/0x124)
[ 2158.173036] [<c0086214>] (handle_percpu_devid_irq+0x9c/0x124) from [<c0082bd8>] (generic_handle_irq+0x20/0x30)
[ 2158.173049] [<c0082bd8>] (generic_handle_irq+0x20/0x30) from [<c000969c>] (handle_IRQ+0x64/0x8c)
[ 2158.173060] [<c000969c>] (handle_IRQ+0x64/0x8c) from [<c0008544>] (gic_handle_irq+0x3c/0x60)
[ 2158.173074] [<c0008544>] (gic_handle_irq+0x3c/0x60) from [<c02f0f80>] (__irq_svc+0x40/0x50)
[ 2158.173083] Exception stack(0xc4043c98 to 0xc4043ce0)
[ 2158.173092] 3c80:                                                       c4043ce4 00000019
[ 2158.173102] 3ca0: 1f8a865f c050ad10 1f8a864c 00000031 c04b5970 0003ebce 00000000 f3550000
[ 2158.173113] 3cc0: bf00bc68 00000800 0003ebce c4043ce0 c0186d14 c0186cb8 80000013 ffffffff
[ 2158.173130] [<c02f0f80>] (__irq_svc+0x40/0x50) from [<c0186cb8>] (read_current_timer+0x4/0x38)
[ 2158.173145] [<c0186cb8>] (read_current_timer+0x4/0x38) from [<1f8a865f>] (0x1f8a865f)
[ 2183.927097] BUG: soft lockup - CPU#1 stuck for 22s! [io_basic:2073]
[ 2184.002229] Modules linked in: nandflash(O) [last unloaded: nandflash]
Signed-off-by: Wang Kai <morgan.wang@huawei.com>
Signed-off-by: hujianyang <hujianyang@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit f05ff433 upstream.

This is no longer needed with the fixed, new and improved definition
of cpu_has_mips_r2_exec_hazard in <asm/cpu-features.h>.

For a discussion, see http://patchwork.linux-mips.org/patch/9539/.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 9cdf30bd upstream.

Returns a non-zero value if the current processor implementation requires
an IHB instruction to deal with an instruction hazard as per MIPS R2
architecture specification, zero otherwise.

For a discussion, see http://patchwork.linux-mips.org/patch/9539/.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[bwh: Backported to 3.2: trim the CPU type list]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 73bf3c2a upstream.

udelay() in PCI/PCIe read/write callbacks cause 30ms IRQ latency on Octeon
platforms because these operations are called from PCI_OP_READ() and
PCI_OP_WRITE() under raw_spin_lock_irqsave().
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: linux-mips@linux-mips.org
Cc: David Daney <ddaney@cavium.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Masanari Iida <standby24x7@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Mathias <mathias.rulf@nokia.com>
Patchwork: https://patchwork.linux-mips.org/patch/9576/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 4d46a67a upstream.

The lazy cache flushing implemented in the MIPS kernel suffers from a
race condition that is exposed by do_set_pte() in mm/memory.c.

A pre-condition is a file-system that writes to the page from the CPU
in its readpage method and then calls flush_dcache_page(). One example
is ubifs. Another pre-condition is that the dcache flush is postponed
in __flush_dcache_page().

Upon a page fault for an executable mapping not existing in the
page-cache, the following will happen:
1. Write to the page
2. flush_dcache_page
3. flush_icache_page
4. set_pte_at
5. update_mmu_cache (commits the flush of a dcache-dirty page)

Between steps 4 and 5 another thread can hit the same page and it will
encounter a valid pte. Because the data still is in the L1 dcache the CPU
will fetch stale data from L2 into the icache and execute garbage.

This fix moves the commit of the cache flush to step 3 to close the
race window. It also reduces the amount of flushes on non-executable
mappings because we never enter __flush_dcache_page() for non-aliasing
CPUs.

Regressions can occur in drivers that mistakenly relies on the
flush_dcache_page() in get_user_pages() for DMA operations.

[ralf@linux-mips.org: Folded in patch 9346 to fix highmem issue.]
Signed-off-by: Lars Persson <larper@axis.com>
Cc: linux-mips@linux-mips.org
Cc: paul.burton@imgtec.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9346/
Patchwork: https://patchwork.linux-mips.org/patch/9738/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 34376a50 upstream.

The stop machine logic can lock up if all but one of the migration
threads make it through the disable-irq step and the one remaining
thread gets stuck in __do_softirq.  The reason __do_softirq can hang is
that it has a bail-out based on jiffies timeout, but in the lockup case,
jiffies itself is not incremented.

To work around this, re-add the max_restart counter in __do_irq and stop
processing irqs after 10 restarts.

Thanks to Tejun Heo and Rusty Russell and others for helping me track
this down.

This was introduced in 3.9 by commit c10d7367 ("softirq: reduce
latencies").

It may be worth looking into ath9k to see if it has issues with its irq
handler at a later date.

The hang stack traces look something like this:

    ------------[ cut here ]------------
    WARNING: at kernel/watchdog.c:245 watchdog_overflow_callback+0x9c/0xa7()
    Watchdog detected hard LOCKUP on cpu 2
    Modules linked in: ath9k ath9k_common ath9k_hw ath mac80211 cfg80211 nfsv4 auth_rpcgss nfs fscache nf_nat_ipv4 nf_nat veth 8021q garp stp mrp llc pktgen lockd sunrpc]
    Pid: 23, comm: migration/2 Tainted: G         C   3.9.4+ #11
    Call Trace:
     <NMI>   warn_slowpath_common+0x85/0x9f
      warn_slowpath_fmt+0x46/0x48
      watchdog_overflow_callback+0x9c/0xa7
      __perf_event_overflow+0x137/0x1cb
      perf_event_overflow+0x14/0x16
      intel_pmu_handle_irq+0x2dc/0x359
      perf_event_nmi_handler+0x19/0x1b
      nmi_handle+0x7f/0xc2
      do_nmi+0xbc/0x304
      end_repeat_nmi+0x1e/0x2e
     <<EOE>>
      cpu_stopper_thread+0xae/0x162
      smpboot_thread_fn+0x258/0x260
      kthread+0xc7/0xcf
      ret_from_fork+0x7c/0xb0
    ---[ end trace 4947dfa9b0a4cec3 ]---
    BUG: soft lockup - CPU#1 stuck for 22s! [migration/1:17]
    Modules linked in: ath9k ath9k_common ath9k_hw ath mac80211 cfg80211 nfsv4 auth_rpcgss nfs fscache nf_nat_ipv4 nf_nat veth 8021q garp stp mrp llc pktgen lockd sunrpc]
    irq event stamp: 835637905
    hardirqs last  enabled at (835637904): __do_softirq+0x9f/0x257
    hardirqs last disabled at (835637905): apic_timer_interrupt+0x6d/0x80
    softirqs last  enabled at (5654720): __do_softirq+0x1ff/0x257
    softirqs last disabled at (5654725): irq_exit+0x5f/0xbb
    CPU 1
    Pid: 17, comm: migration/1 Tainted: G        WC   3.9.4+ #11 To be filled by O.E.M. To be filled by O.E.M./To be filled by O.E.M.
    RIP: tasklet_hi_action+0xf0/0xf0
    Process migration/1
    Call Trace:
     <IRQ>
      __do_softirq+0x117/0x257
      irq_exit+0x5f/0xbb
      smp_apic_timer_interrupt+0x8a/0x98
      apic_timer_interrupt+0x72/0x80
     <EOI>
      printk+0x4d/0x4f
      stop_machine_cpu_stop+0x22c/0x274
      cpu_stopper_thread+0xae/0x162
      smpboot_thread_fn+0x258/0x260
      kthread+0xc7/0xcf
      ret_from_fork+0x7c/0xb0
Signed-off-by: Ben Greear <greearb@candelatech.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Pekka Riikonen <priikone@iki.fi>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>

commit c10d7367 upstream.

In various network workloads, __do_softirq() latencies can be up
to 20 ms if HZ=1000, and 200 ms if HZ=100.

This is because we iterate 10 times in the softirq dispatcher,
and some actions can consume a lot of cycles.

This patch changes the fallback to ksoftirqd condition to :

- A time limit of 2 ms.
- need_resched() being set on current task

When one of this condition is met, we wakeup ksoftirqd for further
softirq processing if we still have pending softirqs.

Using need_resched() as the only condition can trigger RCU stalls,
as we can keep BH disabled for too long.

I ran several benchmarks and got no significant difference in
throughput, but a very significant reduction of latencies (one order
of magnitude) :

In following bench, 200 antagonist "netperf -t TCP_RR" are started in
background, using all available cpus.

Then we start one "netperf -t TCP_RR", bound to the cpu handling the NIC
IRQ (hard+soft)

Before patch :

# netperf -H 7.7.7.84 -t TCP_RR -T2,2 -- -k
RT_LATENCY,MIN_LATENCY,MAX_LATENCY,P50_LATENCY,P90_LATENCY,P99_LATENCY,MEAN_LATENCY,STDDEV_LATENCY
MIGRATED TCP REQUEST/RESPONSE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET
to 7.7.7.84 () port 0 AF_INET : first burst 0 : cpu bind
RT_LATENCY=550110.424
MIN_LATENCY=146858
MAX_LATENCY=997109
P50_LATENCY=305000
P90_LATENCY=550000
P99_LATENCY=710000
MEAN_LATENCY=376989.12
STDDEV_LATENCY=184046.92

After patch :

# netperf -H 7.7.7.84 -t TCP_RR -T2,2 -- -k
RT_LATENCY,MIN_LATENCY,MAX_LATENCY,P50_LATENCY,P90_LATENCY,P99_LATENCY,MEAN_LATENCY,STDDEV_LATENCY
MIGRATED TCP REQUEST/RESPONSE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET
to 7.7.7.84 () port 0 AF_INET : first burst 0 : cpu bind
RT_LATENCY=40545.492
MIN_LATENCY=9834
MAX_LATENCY=78366
P50_LATENCY=33583
P90_LATENCY=59000
P99_LATENCY=69000
MEAN_LATENCY=38364.67
STDDEV_LATENCY=12865.26
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Miller <davem@davemloft.net>
Cc: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Rui Xiang <rui.xiang@huawei.com>

commit fa8cbaaf upstream.

Since commit 8a0a9bd4, this comment in mmap_rnd() does not
hold true as the value returned by get_random_int() will in fact be

different every single call. Remove the comment and simplify the code
back to its original desired form.

This reverts commit a5adc91a which is no longer necessary and
also fixes the sparc code that copied this same adjustment.
Signed-off-by: Dan McGee <dpmcgee@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Moritz Mühlenhoff <jmm@inutil.org>

commit 73af963f upstream.

__ptrace_may_access() checks get_dumpable/ptrace_has_cap/etc if task !=
current, this can can lead to surprising results.

For example, a sub-thread can't readlink("/proc/self/exe") if the
executable is not readable.  setup_new_exec()->would_dump() notices that
inode_permission(MAY_READ) fails and then it does
set_dumpable(suid_dumpable).  After that get_dumpable() fails.

(It is not clear why proc_pid_readlink() checks get_dumpable(), perhaps we
could add PTRACE_MODE_NODUMPABLE)

Change __ptrace_may_access() to use same_thread_group() instead of "task
== current".  Any security check is pointless when the tasks share the
same ->mm.
Signed-off-by: Mark Grondona <mgrondona@llnl.gov>
Signed-off-by: Ben Woodard <woodard@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Sheng Yong <shengyong1@huawei.com>

commit e1403b8e upstream.

task_struct->pid/tgid should go away.

1. Change same_thread_group() to use task->signal for comparison.

2. Change has_group_leader_pid(task) to compare task_pid(task) with
   signal->leader_pid.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Sergey Dyasly <dserrg@gmail.com>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Sheng Yong <shengyong1@huawei.com>

commit 55c844a4 upstream.

When rebooting our 24 CPU Westmere servers with 3.4-rc6, we
always see this warning msg:

Restarting system.
machine restart
------------[ cut here ]------------
WARNING: at arch/x86/kernel/smp.c:125
native_smp_send_reschedule+0x74/0xa7() Hardware name: X8DTN
Modules linked in: igb [last unloaded: scsi_wait_scan]
Pid: 1, comm: systemd-shutdow Not tainted 3.4.0-rc6+ #22
Call Trace:
 <IRQ>  [<ffffffff8102a41f>] warn_slowpath_common+0x7e/0x96
 [<ffffffff8102a44c>] warn_slowpath_null+0x15/0x17
 [<ffffffff81018cf7>] native_smp_send_reschedule+0x74/0xa7
 [<ffffffff810561c1>] trigger_load_balance+0x279/0x2a6
 [<ffffffff81050112>] scheduler_tick+0xe0/0xe9
 [<ffffffff81036768>] update_process_times+0x60/0x70
 [<ffffffff81062f2f>] tick_sched_timer+0x68/0x92
 [<ffffffff81046e33>] __run_hrtimer+0xb3/0x13c
 [<ffffffff81062ec7>] ? tick_nohz_handler+0xd0/0xd0
 [<ffffffff810474f2>] hrtimer_interrupt+0xdb/0x198
 [<ffffffff81019a35>] smp_apic_timer_interrupt+0x81/0x94
 [<ffffffff81655187>] apic_timer_interrupt+0x67/0x70
 <EOI>  [<ffffffff8101a3c4>] ? default_send_IPI_mask_allbutself_phys+0xb4/0xc4
 [<ffffffff8101c680>] physflat_send_IPI_allbutself+0x12/0x14
 [<ffffffff81018db4>] native_nmi_stop_other_cpus+0x8a/0xd6
 [<ffffffff810188ba>] native_machine_shutdown+0x50/0x67
 [<ffffffff81018926>] machine_shutdown+0xa/0xc
 [<ffffffff8101897e>] native_machine_restart+0x20/0x32
 [<ffffffff810189b0>] machine_restart+0xa/0xc
 [<ffffffff8103b196>] kernel_restart+0x47/0x4c
 [<ffffffff8103b2e6>] sys_reboot+0x13e/0x17c
 [<ffffffff8164e436>] ? _raw_spin_unlock_bh+0x10/0x12
 [<ffffffff810fcac9>] ? bdi_queue_work+0xcf/0xd8
 [<ffffffff810fe82f>] ? __bdi_start_writeback+0xae/0xb7
 [<ffffffff810e0d64>] ? iterate_supers+0xa3/0xb7
 [<ffffffff816547a2>] system_call_fastpath+0x16/0x1b
---[ end trace 320af5cb1cb60c5b ]---

The root cause seems to be the
default_send_IPI_mask_allbutself_phys() takes quite some time (I
measured it could be several ms) to complete sending NMIs to all
the other 23 CPUs, and for HZ=250/1000 system, the time is long
enough for a timer interrupt to happen, which will in turn
trigger to kick load balance to a stopped CPU and cause this
warning in native_smp_send_reschedule().

So disabling the local irq before stop_other_cpu() can fix this
problem (tested 25 times reboot ok), and it is fine as there
should be nobody caring the timer interrupt in such reboot
stage.

The latest 3.4 kernel slightly changes this behavior by sending
REBOOT_VECTOR first and only send NMI_VECTOR if the REBOOT_VCTOR
fails, and this patch is still needed to prevent the problem.
Signed-off-by: Feng Tang <feng.tang@intel.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120530231541.4c13433a@feng-i7Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Vinson Lee <vlee@twopensource.com>

commit 8c009100 upstream.
Signed-off-by: Jim Snow <jim.snow@intel.com>
Signed-off-by: Lukasz Anaczkowski <lukasz.anaczkowski@intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Vinson Lee <vlee@twopensource.com>
[lizf: Backported to 3.4:
 - adjust context
 - use debugf0() instead of edac_dbg()]
Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 5b889e37 upstream.

As reported by Josh Boyer <jwboyer@redhat.com>:
>	drivers/edac/sb_edac.c: In function 'get_memory_error_data':
> 	drivers/edac/sb_edac.c:861:2: warning: left shift count >= width of type
> 	[enabled by default]
> 	<snip>
> 	ERROR: "__udivdi3" [drivers/edac/sb_edac.ko] undefined!
> 	make[1]: *** [__modpost] Error 1
> 	make: *** [modules] Error 2

PS.: compile-tested only
Reported-by: Josh Boyer <jwboyer@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
[bwh: Prerequisite for "sb_edac: Fix erroneous bytes->gigabytes conversion"]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit a6dfa128 upstream.

A huge amount of NIC drivers use the DMA API, however if
compiled under 32-bit an very important part of the DMA API can
be ommitted leading to the drivers not working at all
(especially if used with 'swiotlb=force iommu=soft').

As Prashant Sreedharan explains it: "the driver [tg3] uses
DEFINE_DMA_UNMAP_ADDR(), dma_unmap_addr_set() to keep a copy of
the dma "mapping" and dma_unmap_addr() to get the "mapping"
value. On most of the platforms this is a no-op, but ... with
"iommu=soft and swiotlb=force" this house keeping is required,
... otherwise we pass 0 while calling pci_unmap_/pci_dma_sync_
instead of the DMA address."

As such enable this even when using 32-bit kernels.
Reported-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Prashant Sreedharan <prashant@broadcom.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Chan <mchan@broadcom.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: boris.ostrovsky@oracle.com
Cc: cascardo@linux.vnet.ibm.com
Cc: david.vrabel@citrix.com
Cc: sanjeevb@broadcom.com
Cc: siva.kallam@broadcom.com
Cc: vyasevich@gmail.com
Cc: xen-devel@lists.xensource.com
Link: http://lkml.kernel.org/r/20150417190448.GA9462@l.oracle.comSigned-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 3.2: also change the def_bool (cond) to
 def_bool y + depends]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

Based on 08adb7da upstream.

We found that after v3.10.73, recvmsg might return -EFAULT while -EINVAL
was expected.

We tested it through the recvmsg01 testcase come from LTP testsuit. It set
msg->msg_namelen to -1 and the recvmsg syscall returned errno 14, which is
unexpected (errno 22 is expected):

recvmsg01    4  TFAIL  :  invalid socket length ; returned -1 (expected -1),
errno 14 (expected 22)

Linux mainline has no this bug for commit 08adb7da fixes it accidentally.
However, it is too large and complex to be backported to LTS 3.10.

Commit 281c9c36 (net: compat: Update get_compat_msghdr() to match
copy_msghdr_from_user() behaviour) made get_compat_msghdr() return
error if msg_sys->msg_namelen was negative, which changed the behaviors
of recvmsg and sendmsg syscall in a lib32 system:

Before commit 281c9c36, get_compat_msghdr() wouldn't fail and it would
return -EINVAL in move_addr_to_user() or somewhere if msg_sys->msg_namelen
was invalid and then syscall returned -EINVAL, which is correct.

And now, when msg_sys->msg_namelen is negative, get_compat_msghdr() will
fail and wants to return -EINVAL, however, the outer syscall will return
-EFAULT directly, which is unexpected.

This patch gets the return value of get_compat_msghdr() as well as
copy_msghdr_from_user(), then returns this expected value if
get_compat_msghdr() fails.

Fixes: 281c9c36 (net: compat: Update get_compat_msghdr() to match copy_msghdr_from_user() behaviour)
Signed-off-by: Junling Zheng <zhengjunling@huawei.com>
Signed-off-by: Hanbing Xu <xuhanbing@huawei.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

commit 43d77867 upstream.

Current implementation of unfreeze_partials() is so complicated,
but benefit from it is insignificant. In addition many code in
do {} while loop have a bad influence to a fail rate of cmpxchg_double_slab.
Under current implementation which test status of cpu partial slab
and acquire list_lock in do {} while loop,
we don't need to acquire a list_lock and gain a little benefit
when front of the cpu partial slab is to be discarded, but this is a rare case.
In case that add_partial is performed and cmpxchg_double_slab is failed,
remove_partial should be called case by case.

I think that these are disadvantages of current implementation,
so I do refactoring unfreeze_partials().

Minimizing code in do {} while loop introduce a reduced fail rate
of cmpxchg_double_slab. Below is output of 'slabinfo -r kmalloc-256'
when './perf stat -r 33 hackbench 50 process 4000 > /dev/null' is done.

** before **
Cmpxchg_double Looping
------------------------
Locked Cmpxchg Double redos   182685
Unlocked Cmpxchg Double redos 0

** after **
Cmpxchg_double Looping
------------------------
Locked Cmpxchg Double redos   177995
Unlocked Cmpxchg Double redos 1

We can see cmpxchg_double_slab fail rate is improved slightly.

Bolow is output of './perf stat -r 30 hackbench 50 process 4000 > /dev/null'.

** before **
 Performance counter stats for './hackbench 50 process 4000' (30 runs):

     108517.190463 task-clock                #    7.926 CPUs utilized            ( +-  0.24% )
         2,919,550 context-switches          #    0.027 M/sec                    ( +-  3.07% )
           100,774 CPU-migrations            #    0.929 K/sec                    ( +-  4.72% )
           124,201 page-faults               #    0.001 M/sec                    ( +-  0.15% )
   401,500,234,387 cycles                    #    3.700 GHz                      ( +-  0.24% )
   <not supported> stalled-cycles-frontend
   <not supported> stalled-cycles-backend
   250,576,913,354 instructions              #    0.62  insns per cycle          ( +-  0.13% )
    45,934,956,860 branches                  #  423.297 M/sec                    ( +-  0.14% )
       188,219,787 branch-misses             #    0.41% of all branches          ( +-  0.56% )

      13.691837307 seconds time elapsed                                          ( +-  0.24% )

** after **
 Performance counter stats for './hackbench 50 process 4000' (30 runs):

     107784.479767 task-clock                #    7.928 CPUs utilized            ( +-  0.22% )
         2,834,781 context-switches          #    0.026 M/sec                    ( +-  2.33% )
            93,083 CPU-migrations            #    0.864 K/sec                    ( +-  3.45% )
           123,967 page-faults               #    0.001 M/sec                    ( +-  0.15% )
   398,781,421,836 cycles                    #    3.700 GHz                      ( +-  0.22% )
   <not supported> stalled-cycles-frontend
   <not supported> stalled-cycles-backend
   250,189,160,419 instructions              #    0.63  insns per cycle          ( +-  0.09% )
    45,855,370,128 branches                  #  425.436 M/sec                    ( +-  0.10% )
       169,881,248 branch-misses             #    0.37% of all branches          ( +-  0.43% )

      13.596272341 seconds time elapsed                                          ( +-  0.22% )

No regression is found, but rather we can see slightly better result.
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Zefan Li <lizefan@huawei.com>

Commit 915f4f86 ("debugfs: leave freeing a symlink body until inode
eviction", commit 0db59e59 upstream) changed debugfs to define its
own super_operations and implement the evict_inode operation.

Luis Henriques pointed out that it needs to define the statfs
operation, as in simple_super_operations which it was using before.
Reported-by: Luis Henriques <luis.henriques@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>