Commit Graph

601971 Commits

Author SHA1 Message Date
Andrew F. Davis 6b891a2647 gpio: Only descend into gpio directory when CONFIG_GPIOLIB is set
When CONFIG_GPIOLIB is not set make will still descend into the gpio
directory but nothing will be built. This produces unneeded build
artifacts and messages in addition to slowing the build. Fix this here.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-14 08:58:06 +02:00
Andrew Jeffery 3a0000f0ca gpio: Fix paths to GPIO driver source files
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-13 09:30:31 +02:00
Vignesh R a246b8198f gpio: pca953x: Fix NBANK calculation for PCA9536
NBANK() macro assumes that ngpios is a multiple of 8(BANK_SZ) and
hence results in 0 banks for PCA9536 which has just 4 gpios. This is
wrong as PCA9356 has 1 bank with 4 gpios. This results in uninitialized
PCA953X_INVERT register. Fix this by using DIV_ROUND_UP macro in
NBANK().

Cc: stable@vger.kernel.org
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-13 09:21:28 +02:00
Christian Lamparter c0d30ecfe2 gpio: mmio: add MyBook Live GPIO support
This patch adds support for the Western Digital's
MyBook Live memory-mapped GPIO controllers.

The GPIOs will be supported by the generic driver
for memory-mapped GPIO controllers.

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 11:16:50 +02:00
Álvaro Fernández Rojas e698613ada gpio: mmio: add DT support for memory-mapped GPIOs
This patch adds support for defining memory-mapped GPIOs which
are compatible with the existing gpio-mmio interface. The generic
library provides support for many memory-mapped GPIO controllers
that are found in various on-board FPGA and ASIC solutions that
are used to control board's switches, LEDs, chip-selects,
Ethernet/USB PHY power, etc.

For setting GPIOs there are three configurations:
	1. single input/output register resource (named "dat"),
	2. set/clear pair (named "set" and "clr"),
	3. single output register resource and single input resource
	   ("set" and dat").

The configuration is detected by which resources are present.
For the single output register, this drives a 1 by setting a bit
and a zero by clearing a bit.  For the set clr pair, this drives
a 1 by setting a bit in the set register and clears it by setting
a bit in the clear register.

For setting the GPIO direction, there are three configurations:
	a. simple bidirectional GPIOs that requires no configuration.
	b. an output direction register (named "dirout")
	   where a 1 bit indicates the GPIO is an output.
	c. an input direction register (named "dirin")
	   where a 1 bit indicates the GPIO is an input.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 11:15:11 +02:00
Paul Gortmaker 54b729987b gpio: lpc18xx: convert GPIO_LPC18XX from bool to tristate
The Kconfig currently controlling compilation of this code is:

 config GPIO_LPC18XX
       bool "NXP LPC18XX/43XX GPIO support"

...meaning that it currently is not being built as a module by anyone.

When targeting orphaned modular code in non-modular drivers, this
came up.  Joachim indicated that the driver was actually meant to
be tristate but ended up bool by accident.  So here we make it
tristate instead of removing the modular code that was essentially
orphaned.

Cc: Joachim Eastwood <manabian@gmail.com>
Acked-by: Joachim Eastwood <manabian@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: linux-gpio@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 11:04:01 +02:00
Kamlakant Patel baa1b920a8 gpio: Add ACPI support for XLP GPIO controller
Add ACPI support for GPIO controller on Broadcom Vulcan ARM64.
ACPI ID for this device is BRCM9006.

Signed-off-by: Kamlakant Patel <kamlakant.patel@broadcom.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:54:13 +02:00
Kamlakant Patel 1630a0624a gpio: xlp: Fix vulcan IRQ descriptor allocation
irq_alloc_descs need not be called in case of Vulcan, where we use
a dynamic IRQ range for GPIO interrupt numbers.

Update code not to call irq_alloc_descs and pass 0 as irq_base in
case of Vulcan.

Signed-off-by: Kamlakant Patel <kamlakant.patel@broadcom.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:52:49 +02:00
Alexander Shiyan 1bdb5c8e03 gpio: clps711x: Remove board support
Since board support for the CLPS711X platform was removed,
remove the board support from the driver.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:49:58 +02:00
Alexander Shiyan 2e607fca7a gpio: syscon: Change the compatibility string
This patch changes the compatibility string to match with the smallest
supported chip (EP7209). Since the DT-support for this CPU is not yet
announced, this change is safe.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:48:17 +02:00
Alexander Shiyan 1a4d458bdf gpio: clps711x: Change the compatibility string
This patch changes the compatibility string to match with the smallest
supported chip (EP7209). Since the DT-support for this CPU is not yet
announced, this change is safe.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:48:09 +02:00
Iban Rodriguez 8e7c1b803d gpio: xilinx: Add support to set multiple GPIO at once
Add function to set multiple GPIO of the same chip at the same time
and register it

Signed-off-by: Iban Rodriguez <irodriguez@cemitec.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:33:45 +02:00
Andy Shevchenko c4d1cbd7cf gpio: pca953x: enfore type for i2c_smbus_write_word_data()
The commit 9b8e3ec343 ("gpio: pca953x: Use correct u16 value for register
word write") fixed regression in pca953x_write_regs(). At the same time the
solution introduced a sparse warning:

drivers/gpio/gpio-pca953x.c:168:39: warning: incorrect type in argument 3 (different base types)
drivers/gpio/gpio-pca953x.c:168:39:    expected unsigned short [unsigned] [usertype] value
drivers/gpio/gpio-pca953x.c:168:39:    got restricted __le16 [usertype] <noident>

Fix the code by enforcing the type of i2c_smbus_write_word_data() parameter.

Cc: Yong Li <sdliyong@gmail.com>
Cc: Phil Reid <preid@electromag.com.au>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:02:24 +02:00
Linus Walleij 0ee3741499 microblaze: remove ARCH_WANT_OPTIONAL_GPIOLIB
This symbols is not needed to get access to selecting the
GPIOLIB anymore: any arch can select GPIOLIB.

Cc: Michael Büsch <m@bues.ch>
Cc: Michal Simek <monstr@monstr.eu>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 09:56:46 +02:00
Linus Walleij b14dbe6ffa ia64: remove ARCH_WANT_OPTIONAL_GPIOLIB
This symbols is not needed to get access to selecting the
GPIOLIB anymore: any arch can select GPIOLIB.

Cc: Michael Büsch <m@bues.ch>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 09:56:17 +02:00
Linus Walleij c40d54a184 unicore: do away with ARCH_REQUIRE_GPIOLIB
Replace "select ARCH_REQUIRE_GPIOLIB" with "select GPIOLIB"
as this can now be selected directly.

Cc: Michael Büsch <m@bues.ch>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 09:55:46 +02:00
Linus Walleij fdcfdfa1b5 sh: do away with ARCH_[WANT_OPTIONAL|REQUIRE]_GPIOLIB
This replaces:

- "select ARCH_REQUIRE_GPIOLIB" with "select GPIOLIB" as this can
  now be selected directly.

- "select ARCH_WANT_OPTIONAL_GPIOLIB" with no dependency: GPIOLIB
  is now selectable by everyone, so we need not declare our
  intent to select it.

When ordering the symbols the following rationale was used:
if the selects were in alphabetical order, I moved select GPIOLIB
to be in alphabetical order, but if the selects were not
maintained in alphabetical order, I just replaced
"select ARCH_REQUIRE_GPIOLIB" with "select GPIOLIB".

Cc: Michael Büsch <m@bues.ch>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: linux-sh@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 09:55:20 +02:00
Linus Walleij 86c55af4a4 powerpc: do away with ARCH_[WANT_OPTIONAL|REQUIRE]_GPIOLIB
This replaces:

- "select ARCH_REQUIRE_GPIOLIB" with "select GPIOLIB" as this can
  now be selected directly.

- "select ARCH_WANT_OPTIONAL_GPIOLIB" with no dependency: GPIOLIB
  is now selectable by everyone, so we need not declare our
  intent to select it.

When ordering the symbols the following rationale was used:
if the selects were in alphabetical order, I moved select GPIOLIB
to be in alphabetical order, but if the selects were not
maintained in alphabetical order, I just replaced
"select ARCH_REQUIRE_GPIOLIB" with "select GPIOLIB".

Cc: Michael Büsch <m@bues.ch>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 09:54:53 +02:00
Linus Walleij 8636f344cf openrisc: do away with ARCH_REQUIRE_GPIOLIB
Replace "select ARCH_REQUIRE_GPIOLIB" with "select GPIOLIB"
as this can now be selected directly.

Cc: Michael Büsch <m@bues.ch>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: linux@lists.openrisc.net
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 09:54:19 +02:00
Linus Walleij 86ede3d41b pinctrl: xway: use devm_gpiochip_add_data()
Avoid a gpiochip_free() and use standard functions.

Cc: John Crispin <blogic@openwrt.org>
Cc: Pramod Gurav <pramod.gurav@smartplayin.com>
Cc: Martin Schiller <mschiller@tdt.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-07 09:37:21 +02:00
Andy Shevchenko 8c7a92dad1 gpio: pca953x: remove redundant assignments
There are few redundant assignments of ret variable which is updated anyway.
Remove them for good.

While here, correct indentation of the constant definition and remove one empty
line.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-07 09:35:17 +02:00
Linus Walleij d4f80b8199 hexagon: update TODO list
The symbol that will be selected when GPIO is implemented
for Hexagon will be GPIOLIB, we have removed
ARCH_REQUIRE_GPIOLIB and ARCH_WANT_OPTIONAL_GPIOLIB.

Cc: Michael Büsch <m@bues.ch>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: linux-hexagon@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-07 09:35:16 +02:00
Kishon Vijay Abraham I adc2847550 gpio: pcf857x: restore the initial line state of all pcf lines
The reset values for all the PCF lines are high and hence on
shutdown we should drive all the lines high in order to
bring it to the reset state.

This is actually required since PCF doesn't have a reset
line and even after warm reset (by invoking "reboot" in
prompt) the PCF lines maintains it's previous programmed
state. This becomes a problem if the boards are designed to
work with the default initial state.

DRA7XX_evm uses PCF8575 and one of the PCF output lines
feeds to MMC/SD VDD and this line should be driven high in order
for the MMC/SD to be detected.  This line is modelled as
regulator and the hsmmc driver takes care of enabling and
disabling it. In the case of 'reboot', during shutdown path
as part of it's cleanup process the hsmmc driver disables
this regulator. This makes MMC *boot* not functional.

Fix it by driving all the pcf lines high.

This patch was sent long back
(https://patchwork.ozlabs.org/patch/420382/)
But there was a concern that contention might occur if the
PCF shutdown handler is invoked before the shutdown handler
of the PCF's consumers. In that case PCF shutdown handler can't
drive all the pcf lines high without knowing if the PCF
consumers are still active.

However commit 52cdbdd498 ("driver core: correct device's
shutdown order") will make sure shutdown handler of PCF's
consumers are invoked before invoking the shutdown
handler of PCF. So it should be safe to merge this now.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-07 09:35:16 +02:00
Masahiro Yamada 2ec64c9d0d gpio: remove redundant owner assignments of drivers
A platform_driver need not set an owner since it will be populated
by platform_driver_register().
Likewise for mcb_driver (gpio-menz127.c).

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-07 09:35:16 +02:00
Masahiro Yamada 602cf63875 gpio: of: add missing of_node_put() to of_gpiochip_add_pin_range()
As the comment block of of_parse_phandle_with_fixed_args() says,
the caller is responsible to call of_node_put() on the returned
node when done.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-07 09:35:16 +02:00
Laxman Dewangan 23087a0500 gpio: max77620: use the new open drain callback
The MAX77620 have a GPIO pins which can act as open drain or
push pull mode. Implement support for controlling this from GPIO
descriptor tables or other hardware descriptions such as
device tree by implementing the .set_single_ended() callback.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-07 09:35:16 +02:00
Laxman Dewangan ff93ec7496 gpio: max77620: Configure interrupt trigger level
The GPIO sub modules of MAX77620 offers to configure the GPIO
interrupt trigger level as RISING and FALLING edge.

Pass this information to regmap-irg when registering for GPIO
interrupts.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-07 09:35:15 +02:00
Linus Walleij 8e293fb057 gpio: stmpe: implement .get_direction()
This implements the .get_direction() callback for the STMPE
expander GPIO.

Cc: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-07 09:35:15 +02:00
Vignesh R 353661dfe1 gpio: pca953x: Add support for TI PCA9536
TI PCA9536 is 4-Bit I2C GPIO expander without interrupt support[1].
Add support for the same.

[1] TRM: http://www.ti.com/lit/ds/symlink/pca9536.pdf

Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-07 09:35:15 +02:00
Laxman Dewangan 02c5ba1ee9 gpio: max77620: add gpio driver for MAX77620/MAX20024
MAXIM Semiconductor's PMIC, MAX77620/MAX20024 has 8 GPIO
pins. It also supports interrupts from these pins.

Add GPIO driver for these pins to control via GPIO APIs.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-07 09:35:15 +02:00
Laxman Dewangan f72677939c gpio: add DT binding doc for gpio of PMIC max77620/max20024
Maxim Semiconductor's PMIC MAX77620/MAX20024 has 8 GPIO pins
which act as GPIO as well as special function mode.

Add DT binding document to support these pins in GPIO
mode via GPIO framework.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-07 09:35:15 +02:00
Linus Torvalds af8c34ce6a Linux 4.7-rc2 2016-06-05 14:31:26 -07:00
Linus Torvalds 5975b2c0c1 Merge branch 'parisc-4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc fixes from Helge Deller:

 - Fix printk time stamps on SMP systems which got wrong due to a patch
   which was added during the merge window

 - Fix two bugs in the stack backtrace code: Races in module unloading
   and possible invalid accesses to memory due to wrong instruction
   decoding (Mikulas Patocka)

 - Fix userspace crash when syscalls access invalid unaligned userspace
   addresses.  Those syscalls will now return EFAULT as expected.
   (tagged for stable kernel series)

* 'parisc-4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Move die_if_kernel() prototype into traps.h header
  parisc: Fix pagefault crash in unaligned __get_user() call
  parisc: Fix printk time during boot
  parisc: Fix backtrace on PA-RISC
2016-06-05 11:15:33 -07:00
Linus Torvalds d834502e2f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull key handling update from James Morris:
 "This alters a new keyctl function added in the current merge window to
  allow for a future extension planned for the next merge window"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  KEYS: Add placeholder for KDF usage with DH
2016-06-05 11:02:00 -07:00
Eric W. Biederman eedf265aa0 devpts: Make each mount of devpts an independent filesystem.
The /dev/ptmx device node is changed to lookup the directory entry "pts"
in the same directory as the /dev/ptmx device node was opened in.  If
there is a "pts" entry and that entry is a devpts filesystem /dev/ptmx
uses that filesystem.  Otherwise the open of /dev/ptmx fails.

The DEVPTS_MULTIPLE_INSTANCES configuration option is removed, so that
userspace can now safely depend on each mount of devpts creating a new
instance of the filesystem.

Each mount of devpts is now a separate and equal filesystem.

Reserved ttys are now available to all instances of devpts where the
mounter is in the initial mount namespace.

A new vfs helper path_pts is introduced that finds a directory entry
named "pts" in the directory of the passed in path, and changes the
passed in path to point to it.  The helper path_pts uses a function
path_parent_directory that was factored out of follow_dotdot.

In the implementation of devpts:
 - devpts_mnt is killed as it is no longer meaningful if all mounts of
   devpts are equal.
 - pts_sb_from_inode is replaced by just inode->i_sb as all cached
   inodes in the tty layer are now from the devpts filesystem.
 - devpts_add_ref is rolled into the new function devpts_ptmx.  And the
   unnecessary inode hold is removed.
 - devpts_del_ref is renamed devpts_release and reduced to just a
   deacrivate_super.
 - The newinstance mount option continues to be accepted but is now
   ignored.

In devpts_fs.h definitions for when !CONFIG_UNIX98_PTYS are removed as
they are never used.

Documentation/filesystems/devices.txt is updated to describe the current
situation.

This has been verified to work properly on openwrt-15.05, centos5,
centos6, centos7, debian-6.0.2, debian-7.9, debian-8.2, ubuntu-14.04.3,
ubuntu-15.10, fedora23, magia-5, mint-17.3, opensuse-42.1,
slackware-14.1, gentoo-20151225 (13.0?), archlinux-2015-12-01.  With the
caveat that on centos6 and on slackware-14.1 that there wind up being
two instances of the devpts filesystem mounted on /dev/pts, the lower
copy does not end up getting used.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Greg KH <greg@kroah.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Serge Hallyn <serge.hallyn@ubuntu.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
Cc: Jann Horn <jann@thejh.net>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Florian Weimer <fw@deneb.enyo.de>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-05 10:36:01 -07:00
Helge Deller 58f1c654d1 parisc: Move die_if_kernel() prototype into traps.h header
Signed-off-by: Helge Deller <deller@gmx.de>
2016-06-05 08:49:01 +02:00
Helge Deller 8b78f26088 parisc: Fix pagefault crash in unaligned __get_user() call
One of the debian buildd servers had this crash in the syslog without
any other information:

 Unaligned handler failed, ret = -2
 clock_adjtime (pid 22578): Unaligned data reference (code 28)
 CPU: 1 PID: 22578 Comm: clock_adjtime Tainted: G  E  4.5.0-2-parisc64-smp #1 Debian 4.5.4-1
 task: 000000007d9960f8 ti: 00000001bde7c000 task.ti: 00000001bde7c000

      YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI
 PSW: 00001000000001001111100000001111 Tainted: G            E
 r00-03  000000ff0804f80f 00000001bde7c2b0 00000000402d2be8 00000001bde7c2b0
 r04-07  00000000409e1fd0 00000000fa6f7fff 00000001bde7c148 00000000fa6f7fff
 r08-11  0000000000000000 00000000ffffffff 00000000fac9bb7b 000000000002b4d4
 r12-15  000000000015241c 000000000015242c 000000000000002d 00000000fac9bb7b
 r16-19  0000000000028800 0000000000000001 0000000000000070 00000001bde7c218
 r20-23  0000000000000000 00000001bde7c210 0000000000000002 0000000000000000
 r24-27  0000000000000000 0000000000000000 00000001bde7c148 00000000409e1fd0
 r28-31  0000000000000001 00000001bde7c320 00000001bde7c350 00000001bde7c218
 sr00-03  0000000001200000 0000000001200000 0000000000000000 0000000001200000
 sr04-07  0000000000000000 0000000000000000 0000000000000000 0000000000000000

 IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000402d2e84 00000000402d2e88
  IIR: 0ca0d089    ISR: 0000000001200000  IOR: 00000000fa6f7fff
  CPU:        1   CR30: 00000001bde7c000 CR31: ffffffffffffffff
  ORIG_R28: 00000002369fe628
  IAOQ[0]: compat_get_timex+0x2dc/0x3c0
  IAOQ[1]: compat_get_timex+0x2e0/0x3c0
  RP(r2): compat_get_timex+0x40/0x3c0
 Backtrace:
  [<00000000402d4608>] compat_SyS_clock_adjtime+0x40/0xc0
  [<0000000040205024>] syscall_exit+0x0/0x14

This means the userspace program clock_adjtime called the clock_adjtime()
syscall and then crashed inside the compat_get_timex() function.
Syscalls should never crash programs, but instead return EFAULT.

The IIR register contains the executed instruction, which disassebles
into "ldw 0(sr3,r5),r9".
This load-word instruction is part of __get_user() which tried to read the word
at %r5/IOR (0xfa6f7fff). This means the unaligned handler jumped in.  The
unaligned handler is able to emulate all ldw instructions, but it fails if it
fails to read the source e.g. because of page fault.

The following program reproduces the problem:

#define _GNU_SOURCE
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/mman.h>

int main(void) {
        /* allocate 8k */
        char *ptr = mmap(NULL, 2*4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
        /* free second half (upper 4k) and make it invalid. */
        munmap(ptr+4096, 4096);
        /* syscall where first int is unaligned and clobbers into invalid memory region */
        /* syscall should return EFAULT */
        return syscall(__NR_clock_adjtime, 0, ptr+4095);
}

To fix this issue we simply need to check if the faulting instruction address
is in the exception fixup table when the unaligned handler failed. If it
is, call the fixup routine instead of crashing.

While looking at the unaligned handler I found another issue as well: The
target register should not be modified if the handler was unsuccessful.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
2016-06-05 08:48:24 +02:00
Helge Deller 0032c08833 parisc: Fix printk time during boot
Avoid showing invalid printk time stamps during boot.

Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Aaro Koskinen <aaro.koskinen@iki.fi>
2016-06-05 08:45:09 +02:00
Mikulas Patocka be24a89700 parisc: Fix backtrace on PA-RISC
This patch fixes backtrace on PA-RISC

There were several problems:

1) The code that decodes instructions handles instructions that subtract
from the stack pointer incorrectly. If the instruction subtracts the
number X from the stack pointer the code increases the frame size by
(0x100000000-X).  This results in invalid accesses to memory and
recursive page faults.

2) Because gcc reorders blocks, handling instructions that subtract from
the frame pointer is incorrect. For example, this function
	int f(int a)
	{
		if (__builtin_expect(a, 1))
			return a;
		g();
		return a;
	}
is compiled in such a way, that the code that decreases the stack
pointer for the first "return a" is placed before the code for "g" call.
If we recognize this decrement, we mistakenly believe that the frame
size for the "g" call is zero.

To fix problems 1) and 2), the patch doesn't recognize instructions that
decrease the stack pointer at all. To further safeguard the unwind code
against nonsense values, we don't allow frame size larger than
Total_frame_size.

3) The backtrace is not locked. If stack dump races with module unload,
invalid table can be accessed.

This patch adds a spinlock when processing module tables.

Note, that for correct backtrace, you need recent binutils.
Binutils 2.18 from Debian 5 produce garbage unwind tables.
Binutils 2.21 work better (it sometimes forgets function frames, but at
least it doesn't generate garbage).

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2016-06-04 22:05:07 +02:00
Linus Torvalds 049ec1b5a7 Merge tag 'drm-fixes-for-v4.7-rc2' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
 "A bunch of ARM drivers got into the fixes vibe this time around, so
  this contains a bunch of fixes for imx, atmel hlcdc, arm hdlcd (only
  so many combos of hlcd), mediatek and omap drm.

  Other than that there is one mgag200 fix and a few core drm regression
  fixes"

* tag 'drm-fixes-for-v4.7-rc2' of git://people.freedesktop.org/~airlied/linux: (34 commits)
  drm/omap: fix unused variable warning.
  drm: hdlcd: Add information about the underlying framebuffers in debugfs
  drm: hdlcd: Cleanup the atomic plane operations
  drm/hdlcd: Fix up crtc_state->event handling
  drm: hdlcd: Revamp runtime power management
  drm/mediatek: mtk_dsi: Remove spurious drm_connector_unregister
  drm/mediatek: mtk_dpi: remove invalid error message
  drm: atmel-hlcdc: fix a NULL check
  drm: atmel-hlcdc: fix atmel_hlcdc_crtc_reset() implementation
  drm/mgag200: Black screen fix for G200e rev 4
  drm: Wrap direct calls to driver->gem_free_object from CMA
  drm: fix fb refcount issue with atomic modesetting
  drm: make drm_atomic_set_mode_prop_for_crtc() more reliable
  drm/sti: remove extra mode fixup
  drm: add missing drm_mode_set_crtcinfo call
  drm/omap: include gpio/consumer.h where needed
  drm/omap: include linux/seq_file.h where needed
  Revert "drm/omap: no need to select OMAP2_DSS"
  drm/omap: Remove regulator API abuse
  OMAPDSS: HDMI5: Change DDC timings
  ...
2016-06-04 12:30:36 -07:00
Linus Torvalds f2c6b9e4b2 VFIO fixes for v4.7-rc2
- Fix irqfd shutdown ordering, build warning, and VPD short read
   (Alex Williamson)
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Merge tag 'vfio-v4.7-rc2' of git://github.com/awilliam/linux-vfio

Pull VFIO fixes from Alex Williamson:
 "Fix irqfd shutdown ordering, build warning, and VPD short read"

* tag 'vfio-v4.7-rc2' of git://github.com/awilliam/linux-vfio:
  vfio/pci: Allow VPD short read
  vfio/type1: Fix build warning
  vfio/pci: Fix ordering of eventfd vs virqfd shutdown
2016-06-04 12:25:36 -07:00
Linus Torvalds 95b46aeb05 MMC core:
- Fix/restore behaviour when selecting bus width for (e)MMC
 
 MMC host:
  - sunxi: Fix eMMC HS-DDR modes on Allwinner A80
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Merge tag 'mmc-v4.7-rc1-2' of git://git.linaro.org/people/ulf.hansson/mmc

Pull MMC fixes from Ulf Hansson:
 "MMC core:
   - Fix/restore behaviour when selecting bus width for (e)MMC

  MMC host:
   - sunxi: Fix eMMC HS-DDR modes on Allwinner A80"

* tag 'mmc-v4.7-rc1-2' of git://git.linaro.org/people/ulf.hansson/mmc:
  mmc: sunxi: Re-enable eMMC HS-DDR modes on Allwinner A80
  mmc: sunxi: Fix DDR MMC timings for A80
  mmc: fix mmc mode selection for HS-DDR and higher
2016-06-04 12:20:26 -07:00
Linus Torvalds b2d5ad8223 Merge branch 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "The important part of this pull is Filipe's set of fixes for btrfs
  device replacement.  Filipe fixed a few issues seen on the list and a
  number he found on his own"

* 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: deal with duplciates during extent_map insertion in btrfs_get_extent
  Btrfs: fix race between device replace and read repair
  Btrfs: fix race between device replace and discard
  Btrfs: fix race between device replace and chunk allocation
  Btrfs: fix race setting block group back to RW mode during device replace
  Btrfs: fix unprotected assignment of the left cursor for device replace
  Btrfs: fix race setting block group readonly during device replace
  Btrfs: fix race between device replace and block group removal
  Btrfs: fix race between readahead and device replace/removal
2016-06-04 11:56:28 -07:00
Linus Torvalds a3021a59ca Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull Ceph fixes from Sage Weil:
 "We have a few follow-up fixes for the libceph refactor from Ilya, and
  then some cephfs + fscache fixes from Zheng.

  The first two FS-Cache patches are acked by David Howells and deemed
  trivial enough to go through our tree.  The rest fix some issues with
  the ceph fscache handling (disable cache for inodes opened for write,
  and simplify the revalidation logic accordingly, dropping the
  now-unnecessary work queue)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  ceph: use i_version to check validity of fscache
  ceph: improve fscache revalidation
  ceph: disable fscache when inode is opened for write
  ceph: avoid unnecessary fscache invalidation/revlidation
  ceph: call __fscache_uncache_page() if readpages fails
  FS-Cache: make check_consistency callback return int
  FS-Cache: wake write waiter after invalidating writes
  libceph: use %s instead of %pE in dout()s
  libceph: put request only if it's done in handle_reply()
  libceph: change ceph_osdmap_flag() to take osdc
2016-06-04 11:37:53 -07:00
Linus Torvalds eb10a7b7be ACPI fixes for v4.7-rc2
- Fix an incorrect check introduced by recent ACPICA changes which
    causes problems with booting KVM guests to happen, among other
    things (Lv Zheng).
 
  - Fix a backlight issue introduced by recent changes to the ACPI
    video driver (Aaron Lu).
 
  - Fix the ACPI processor initialization which attempts to register
    an IO region without checking if that really is necessary and
    sometimes prevents drivers loaded subsequently from registering
    their resources which leads to boot issues (Rafael Wysocki).
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Merge tag 'acpi-4.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI fixes from Rafael Wysocki:
 "Two fixes for problems introduced recently (ACPICA and the ACPI
  backlight driver) and one fix for an older issue that prevents at
  least one system from booting.

  Specifics:

   - Fix an incorrect check introduced by recent ACPICA changes which
     causes problems with booting KVM guests to happen, among other
     things (Lv Zheng).

   - Fix a backlight issue introduced by recent changes to the ACPI
     video driver (Aaron Lu).

   - Fix the ACPI processor initialization which attempts to register an
     IO region without checking if that really is necessary and
     sometimes prevents drivers loaded subsequently from registering
     their resources which leads to boot issues (Rafael Wysocki)"

* tag 'acpi-4.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / processor: Avoid reserving IO regions too early
  ACPICA / Hardware: Fix old register check in acpi_hw_get_access_bit_width()
  ACPI / Thermal / video: fix max_level incorrect value
2016-06-04 11:26:49 -07:00
Linus Torvalds 50163203e3 Power management fixes for v4.7-rc2
- Fix a silly mistake related to the clamp_val() usage in
    a function added by a recent commit (Rafael Wysocki).
 
  - Reduce the log level of an annoying message added to intel_pstate
    during the recent merge window (Srinivas Pandruvada).
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Merge tag 'pm-4.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "Two fixes for problems introduced recently in the cpufreq core and the
  intel_pstate driver.

  Specifics:

   - Fix a silly mistake related to the clamp_val() usage in a function
     added by a recent commit (Rafael Wysocki).

   - Reduce the log level of an annoying message added to intel_pstate
     during the recent merge window (Srinivas Pandruvada)"

* tag 'pm-4.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: Fix clamp_val() usage in cpufreq_driver_fast_switch()
  cpufreq: intel_pstate: Downgrade print level for _PPC
2016-06-04 11:07:57 -07:00
Linus Torvalds d46d0256cd Merge branch 'akpm' (patches from Andrew)
Merge various fixes from Andrew Morton:
 "10 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm, page_alloc: recalculate the preferred zoneref if the context can ignore memory policies
  mm, page_alloc: reset zonelist iterator after resetting fair zone allocation policy
  mm, oom_reaper: do not use siglock in try_oom_reaper()
  mm, page_alloc: prevent infinite loop in buffered_rmqueue()
  checkpatch: reduce git commit description style false positives
  mm/z3fold.c: avoid modifying HEADLESS page and minor cleanup
  memcg: add RCU locking around css_for_each_descendant_pre() in memcg_offline_kmem()
  mm: check the return value of lookup_page_ext for all call sites
  kdump: fix dmesg gdbmacro to work with record based printk
  mm: fix overflow in vm_map_ram()
2016-06-04 10:51:29 -07:00
Linus Torvalds 8c52b6dcdd Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
 - a few simple fixes for fallout from the recent gic-v3 changes
 - a workaround for a Cavium thunderX erratum
 - a bugfix for the pic32 irqchip to make external interrupts work proper
 - a missing return value in the generic IPI management code

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/irq-pic32-evic: Fix bug with external interrupts.
  irqchip/gicv3-its: numa: Enable workaround for Cavium thunderx erratum 23144
  irqchip/gic-v3: Fix quiescence check in gic_enable_redist
  irqchip/gic-v3: Fix copy+paste mistakes in defines
  irqchip/gic-v3: Fix ICC_SGI1R_EL1.INTID decoding mask
  genirq: Fix missing return value in irq_destroy_ipi()
2016-06-03 16:12:35 -07:00
Mel Gorman e46e7b77c9 mm, page_alloc: recalculate the preferred zoneref if the context can ignore memory policies
The optimistic fast path may use cpuset_current_mems_allowed instead of
of a NULL nodemask supplied by the caller for cpuset allocations.  The
preferred zone is calculated on this basis for statistic purposes and as
a starting point in the zonelist iterator.

However, if the context can ignore memory policies due to being atomic
or being able to ignore watermarks then the starting point in the
zonelist iterator is no longer correct.  This patch resets the zonelist
iterator in the allocator slowpath if the context can ignore memory
policies.  This will alter the zone used for statistics but only after
it is known that it makes sense for that context.  Resetting it before
entering the slowpath would potentially allow an ALLOC_CPUSET allocation
to be accounted for against the wrong zone.  Note that while nodemask is
not explicitly set to the original nodemask, it would only have been
overwritten if cpuset_enabled() and it was reset before the slowpath was
entered.

Link: http://lkml.kernel.org/r/20160602103936.GU2527@techsingularity.net
Fixes: c33d6c06f6 ("mm, page_alloc: avoid looking up the first zone in a zonelist twice")
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-03 16:02:57 -07:00
Mel Gorman 0d0bd89435 mm, page_alloc: reset zonelist iterator after resetting fair zone allocation policy
Geert Uytterhoeven reported the following problem that bisected to
commit c33d6c06f6 ("mm, page_alloc: avoid looking up the first zone
in a zonelist twice") on m68k/ARAnyM

    BUG: scheduling while atomic: cron/668/0x10c9a0c0
    Modules linked in:
    CPU: 0 PID: 668 Comm: cron Not tainted 4.6.0-atari-05133-gc33d6c06f60f710f #364
    Call Trace: [<0003d7d0>] __schedule_bug+0x40/0x54
      __schedule+0x312/0x388
      __schedule+0x0/0x388
      prepare_to_wait+0x0/0x52
      schedule+0x64/0x82
      schedule_timeout+0xda/0x104
      set_next_entity+0x18/0x40
      pick_next_task_fair+0x78/0xda
      io_schedule_timeout+0x36/0x4a
      bit_wait_io+0x0/0x40
      bit_wait_io+0x12/0x40
      __wait_on_bit+0x46/0x76
      wait_on_page_bit_killable+0x64/0x6c
      bit_wait_io+0x0/0x40
      wake_bit_function+0x0/0x4e
      __lock_page_or_retry+0xde/0x124
      do_scan_async+0x114/0x17c
      lookup_swap_cache+0x24/0x4e
      handle_mm_fault+0x626/0x7de
      find_vma+0x0/0x66
      down_read+0x0/0xe
      wait_on_page_bit_killable_timeout+0x77/0x7c
      find_vma+0x16/0x66
      do_page_fault+0xe6/0x23a
      res_func+0xa3c/0x141a
      buserr_c+0x190/0x6d4
      res_func+0xa3c/0x141a
      buserr+0x20/0x28
      res_func+0xa3c/0x141a
      buserr+0x20/0x28

The relationship is not obvious but it's due to a failure to rescan the
full zonelist after the fair zone allocation policy exhausts the batch
count.  While this is a functional problem, it's also a performance
issue.  A page allocator microbenchmark showed the following

                                   4.7.0-rc1                  4.7.0-rc1
                                     vanilla                 reset-v1r2
  Min      alloc-odr0-1     327.00 (  0.00%)           326.00 (  0.31%)
  Min      alloc-odr0-2     235.00 (  0.00%)           235.00 (  0.00%)
  Min      alloc-odr0-4     198.00 (  0.00%)           198.00 (  0.00%)
  Min      alloc-odr0-8     170.00 (  0.00%)           170.00 (  0.00%)
  Min      alloc-odr0-16    156.00 (  0.00%)           156.00 (  0.00%)
  Min      alloc-odr0-32    150.00 (  0.00%)           150.00 (  0.00%)
  Min      alloc-odr0-64    146.00 (  0.00%)           146.00 (  0.00%)
  Min      alloc-odr0-128   145.00 (  0.00%)           145.00 (  0.00%)
  Min      alloc-odr0-256   155.00 (  0.00%)           155.00 (  0.00%)
  Min      alloc-odr0-512   168.00 (  0.00%)           165.00 (  1.79%)
  Min      alloc-odr0-1024  175.00 (  0.00%)           174.00 (  0.57%)
  Min      alloc-odr0-2048  180.00 (  0.00%)           180.00 (  0.00%)
  Min      alloc-odr0-4096  187.00 (  0.00%)           186.00 (  0.53%)
  Min      alloc-odr0-8192  190.00 (  0.00%)           190.00 (  0.00%)
  Min      alloc-odr0-16384 191.00 (  0.00%)           191.00 (  0.00%)
  Min      alloc-odr1-1     736.00 (  0.00%)           445.00 ( 39.54%)
  Min      alloc-odr1-2     343.00 (  0.00%)           335.00 (  2.33%)
  Min      alloc-odr1-4     277.00 (  0.00%)           270.00 (  2.53%)
  Min      alloc-odr1-8     238.00 (  0.00%)           233.00 (  2.10%)
  Min      alloc-odr1-16    224.00 (  0.00%)           218.00 (  2.68%)
  Min      alloc-odr1-32    210.00 (  0.00%)           208.00 (  0.95%)
  Min      alloc-odr1-64    207.00 (  0.00%)           203.00 (  1.93%)
  Min      alloc-odr1-128   276.00 (  0.00%)           202.00 ( 26.81%)
  Min      alloc-odr1-256   206.00 (  0.00%)           202.00 (  1.94%)
  Min      alloc-odr1-512   207.00 (  0.00%)           202.00 (  2.42%)
  Min      alloc-odr1-1024  208.00 (  0.00%)           205.00 (  1.44%)
  Min      alloc-odr1-2048  213.00 (  0.00%)           212.00 (  0.47%)
  Min      alloc-odr1-4096  218.00 (  0.00%)           216.00 (  0.92%)
  Min      alloc-odr1-8192  341.00 (  0.00%)           219.00 ( 35.78%)

Note that order-0 allocations are unaffected but higher orders get a
small boost from this patch and a large reduction in system CPU usage
overall as can be seen here:

             4.7.0-rc1   4.7.0-rc1
               vanilla  reset-v1r2
  User           85.32       86.31
  System       2221.39     2053.36
  Elapsed      2368.89     2202.47

Fixes: c33d6c06f6 ("mm, page_alloc: avoid looking up the first zone in a zonelist twice")
Link: http://lkml.kernel.org/r/20160531100848.GR2527@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-03 16:02:56 -07:00