Commit Graph

570162 Commits

Author SHA1 Message Date
Linus Torvalds 0cbeafb245 Merge branch 'akpm' (patches from Andrew)
Merge second patch-bomb from Andrew Morton:

 - more MM stuff:

    - Kirill's page-flags rework

    - Kirill's now-allegedly-fixed THP rework

    - MADV_FREE implementation

    - DAX feature work (msync/fsync).  This isn't quite complete but DAX
      is new and it's good enough and the guys have a handle on what
      needs to be done - I expect this to be wrapped in the next week or
      two.

  - some vsprintf maintenance work

  - various other misc bits

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (145 commits)
  printk: change recursion_bug type to bool
  lib/vsprintf: factor out %pN[F] handler as netdev_bits()
  lib/vsprintf: refactor duplicate code to special_hex_number()
  printk-formats.txt: remove unimplemented %pT
  printk: help pr_debug and pr_devel to optimize out arguments
  lib/test_printf.c: test dentry printing
  lib/test_printf.c: add test for large bitmaps
  lib/test_printf.c: account for kvasprintf tests
  lib/test_printf.c: add a few number() tests
  lib/test_printf.c: test precision quirks
  lib/test_printf.c: check for out-of-bound writes
  lib/test_printf.c: don't BUG
  lib/kasprintf.c: add sanity check to kvasprintf
  lib/vsprintf.c: warn about too large precisions and field widths
  lib/vsprintf.c: help gcc make number() smaller
  lib/vsprintf.c: expand field_width to 24 bits
  lib/vsprintf.c: eliminate potential race in string()
  lib/vsprintf.c: move string() below widen_string()
  lib/vsprintf.c: pull out padding code from dentry_name()
  printk: do cond_resched() between lines while outputting to consoles
  ...
2016-01-17 12:58:52 -08:00
Linus Torvalds 58cf279aca Merge tag 'gpio-v4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO updates from Linus Walleij:
 "Here is the bulk of GPIO changes for v4.5.

  Notably there are big refactorings mostly by myself, aimed at getting
  the gpio_chip into a shape that makes me believe I can proceed to
  preserve state for a proper userspace ABI (character device) that has
  already been proposed once, but resulted in the feedback that I need
  to go back and restructure stuff.  So I've been restructuring stuff.
  On the way I ran into brokenness (return code from the get_value()
  callback) and had to fix it.  Also, refactored generic GPIO to be
  simpler.

  Some of that is still waiting to trickle down from the subsystems all
  over the kernel that provide random gpio_chips, I've touched every
  single GPIO driver in the kernel now, oh man I didn't know I was
  responsible for so much...

  Apart from that we're churning along as usual.

  I took some effort to test and retest so it should merge nicely and we
  shook out a couple of bugs in -next.

  Infrastructural changes:

   - In struct gpio_chip, rename the .dev node to .parent to better
     reflect the fact that this is not the GPIO struct device
     abstraction.  We will add that soon so this would be totallt
     confusing.

   - It was noted that the driver .get_value() callbacks was sometimes
     reporting negative -ERR values to the gpiolib core, expecting them
     to be propagated to consumer gpiod_get_value() and gpio_get_value()
     calls.  This was not happening, so as there was a mess of drivers
     returning negative errors and some returning "anything else than
     zero" to indicate that a line was active.  As some would have bit
     31 set to indicate "line active" it clashed with negative error
     codes.  This is fixed by the largeish series clamping values in all
     drivers with !!value to [0,1] and then augmenting the code to
     propagate error codes to consumers.  (Includes some ACKed patches
     in other subsystems.)

   - Add a void *data pointer to struct gpio_chip.  The container_of()
     design pattern is indeed very nice, but we want to reform the
     struct gpio_chip to be a non-volative, stateless business, and keep
     states internal to the gpiolib to be able to hold on to the state
     when adding a proper userspace ABI (character device) further down
     the road.  To achieve this, drivers need a handle at the internal
     state that is not dependent on their struct gpio_chip() so we add
     gpiochip_add_data() and gpiochip_get_data() following the pattern
     of many other subsystems.  All the "use gpiochip data pointer"
     patches transforms drivers to this scheme.

   - The Generic GPIO chip header has been merged into the general
     <linux/gpio/driver.h> header, and the custom header for that
     removed.  Instead of having a separate mm_gpio_chip struct for
     these generic drivers, merge that into struct gpio_chip,
     simplifying the code and removing the need for separate and
     confusing includes.

  Misc improvements:

   - Stabilize the way GPIOs are looked up from the ACPI legacy
     specification.

   - Incremental driver features for PXA, PCA953X, Lantiq (patches from
     the OpenWRT community), RCAR, Zynq, PL061, 104-idi-48

  New drivers:

   - Add a GPIO chip to the ALSA SoC AC97 driver.

   - Add a new Broadcom NSP SoC driver (this lands in the pinctrl dir,
     but the branch is merged here too to account for infrastructural
     changes).

   - The sx150x driver now supports the sx1502"

* tag 'gpio-v4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (220 commits)
  gpio: generic: make bgpio_pdata always visible
  gpiolib: fix chip order in gpio list
  gpio: mpc8xxx: Do not use gpiochip_get_data() in mpc8xxx_gpio_save_regs()
  gpio: mm-lantiq: Do not use gpiochip_get_data() in ltq_mm_save_regs()
  gpio: brcmstb: Allow building driver for BMIPS_GENERIC
  gpio: brcmstb: Set endian flags for big-endian MIPS
  gpio: moxart: fix build regression
  gpio: xilinx: Do not use gpiochip_get_data() in xgpio_save_regs()
  leds: pca9532: use gpiochip data pointer
  leds: tca6507: use gpiochip data pointer
  hid: cp2112: use gpiochip data pointer
  bcma: gpio: use gpiochip data pointer
  avr32: gpio: use gpiochip data pointer
  video: fbdev: via: use gpiochip data pointer
  gpio: pch: Optimize pch_gpio_get()
  Revert "pinctrl: lantiq: Implement gpio_chip.to_irq"
  pinctrl: nsp-gpio: use gpiochip data pointer
  pinctrl: vt8500-wmt: use gpiochip data pointer
  pinctrl: exynos5440: use gpiochip data pointer
  pinctrl: at91-pio4: use gpiochip data pointer
  ...
2016-01-17 12:32:01 -08:00
Linus Torvalds 6606b342fe Merge git://www.linux-watchdog.org/linux-watchdog
Pull watchdog updates from Wim Van Sebroeck:
 "This adds following items:

   - watchdog restart handler support
   - watchdog reboot notifier support
   - watchdog sysfs attributes
   - support for the following new devices: AMD Mullins platform, AMD
     Carrizo platform, meson8b SoC, CSRatlas7, TS-4800, Alphascale
     asm9260-wdt, Zodiac, Sigma Designs SMP86xx/SMP87xx
   - Changes in refcounting for the watchdog core
   - watchdog core improvements
   - and small fixes"

* git://www.linux-watchdog.org/linux-watchdog: (60 commits)
  watchdog: asm9260: remove __init and __exit annotations
  watchdog: Drop pointer to watchdog device from struct watchdog_device
  watchdog: ziirave: Use watchdog infrastructure to create sysfs attributes
  watchdog: Add support for creating driver specific sysfs attributes
  watchdog: kill unref/ref ops
  watchdog: stmp3xxx: Remove unused variables
  watchdog: add MT7621 watchdog support
  hwmon: (sch56xx) Drop watchdog driver data reference count callbacks
  watchdog: da9055_wdt: Drop reference counting
  watchdog: da9052_wdt: Drop reference counting
  watchdog: Separate and maintain variables based on variable lifetime
  watchdog: diag288: Stop re-using watchdog core internal flags
  watchdog: Create watchdog device in watchdog_dev.c
  watchdog: qcom-wdt: Do not set 'dev' in struct watchdog_device
  watchdog: mena21: Do not use device pointer from struct watchdog_device
  watchdog: gpio: Do not use device pointer from struct watchdog_device
  watchdog: tangox: Print info message using pointer to platform device
  watchdog: bcm2835_wdt: Drop log message if watchdog is stopped
  devicetree: watchdog: add binding for Sigma Designs SMP8642 watchdog
  watchdog: add support for Sigma Designs SMP86xx/SMP87xx
  ...
2016-01-17 12:15:38 -08:00
Linus Torvalds a016af2e70 Merge tag 'sound-4.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound updates from Takashi Iwai:
 "We've had quite busy weeks in this cycle.  Looking at ALSA core, the
  significant changes are a few fixes wrt timer and sequencer ioctls
  that have been revealed by fuzzer recently.  Other than that, ASoC
  core got a few updates about DAI link handling, but these are rather
  straightforward refactoring.

  In drivers scene, ASoC received quite lots of new drivers in addition
  to bunch of updates for still ongoing Intel Skylake support and
  topology API.  HD-audio gained a new HDMI/DP hotplug notification via
  component.  FireWire got a pile of code refactoring/updates with
  SCS.1x driver integration.

  More highlights are shown below.

  [ NOTE: this contains also many commits for DRM.  This is due to the
    pull of drm stable branch into sound tree, as the base of i915 audio
    component work for HD-audio.  The highlights below don't contain
    these DRM changes, as these are supposed to be pulled via drm tree
    in anyway sooner or later.  ]

  Core:
   - Handful fixes to harden ALSA timer and sequencer ioctls against
     races reported by syzkaller fuzzer
   - Irq description string can be unique to each card; only for
     HD-audio for now

  ASoC:
   - Conversion of the array of DAI links to a list for supporting
     dynamically adding and removing DAI links
   - Topology API enhancements to make everything more component based
     and being able to specify PCM links via topology
   - Some more fixes for the topology code, though it is still not final
     and ready for enabling in production; we really need to get to the
     point where that can be done
   - A pile of changes for Intel SkyLake drivers which hopefully deliver
     some useful initial functionality for systems with this chipset,
     though there is more work still to come
   - Lots of new features and cleanups for the Renesas drivers
   - ANC support for WM5110
   - New drivers: Imagination Technologies IPs, Atmel class D speaker,
     Cirrus CS47L24 and WM1831, Dialog DA7128, Realtek RT5659 and
     RT56156, Rockchip RK3036, TI PC3168A, and AMD ACP
   - Rename PCM1792a driver to be generic pcm179x

  HD-Audio:
   - Use audio component for i915 HDMI/DP hotplug handling
   - On-demand binding with i915 driver
   - bdl_pos_adj parameter adjustment for Baytrail controllers
   - Enable power_save_node for CX20722; this shouldn't lead to
     regression, hopefully
   - Kabylake HDMI/DP codec support
   - Quirks for Lenovo E50-80, Dell Latitude E-series, and other Dell
     machines
   - A few code refactoring

  FireWire:
   - Lots of code cleanup and refactoring
   - Integrate the support of SCS.1x devices into snd-oxfw driver;
     snd-scs1x driver is obsoleted

  USB-audio:
   - Fix possible NULL dereference at disconnection
   - A regression fix for Native Instruments devices

  Misc:
   - A few code cleanups of fm801 driver"

* tag 'sound-4.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (722 commits)
  ALSA: timer: Code cleanup
  ALSA: timer: Harden slave timer list handling
  ALSA: hda - Add fixup for Dell Latitidue E6540
  ALSA: timer: Fix race among timer ioctls
  ALSA: hda - add codec support for Kabylake display audio codec
  ALSA: timer: Fix double unlink of active_list
  ALSA: usb-audio: Fix mixer ctl regression of Native Instrument devices
  ALSA: hda - fix the headset mic detection problem for a Dell laptop
  ALSA: hda - Fix white noise on Dell Latitude E5550
  ALSA: hda_intel: add card number to irq description
  ALSA: seq: Fix race at timer setup and close
  ALSA: seq: Fix missing NULL check at remove_events ioctl
  ALSA: usb-audio: Avoid calling usb_autopm_put_interface() at disconnect
  ASoC: hdac_hdmi: remove unused hdac_hdmi_query_pin_connlist
  ASoC: AMD: Add missing include file
  ALSA: hda - Fixup inverted internal mic for Lenovo E50-80
  ALSA: usb: Add native DSD support for Oppo HA-1
  ASoC: Make aux_dev more like a generic component
  ASoC: bcm2835: cleanup includes by ordering them alphabetically
  ASoC: AMD: Manage ACP 2.x SRAM banks power
  ...
2016-01-17 12:05:31 -08:00
Linus Torvalds e535d74bc5 Merge tag 'docs-4.5' of git://git.lwn.net/linux
Pull documentation updates from Jon Corbet:
 "A relatively boring cycle in the docs tree.  There's a few kernel-doc
  fixes and various document tweaks.

  One patch reaches out of the documentation subtree to fix a comment in
  init/do_mounts_rd.c.  There didn't seem to be anybody more appropriate
  to take that one, so I accepted it"

* tag 'docs-4.5' of git://git.lwn.net/linux: (29 commits)
  thermal: add description for integral_cutoff unit
  Documentation: update libhugetlbfs site url
  Documentation: Explain pci=conf1,conf2 more verbosely
  DMA-API: fix confusing sentence in Documentation/DMA-API.txt
  Documentation: translations: update linux cross reference link
  Documentation: fix typo in CodingStyle
  init, Documentation: Remove ramdisk_blocksize mentions
  Documentation-getdelays: Apply a recommendation from "checkpatch.pl" in main()
  Documentation: HOWTO: update versions from 3.x to 4.x
  Documentation: remove outdated references from translations
  Doc: treewide: Fix grammar "a" to "an"
  Documentation: cpu-hotplug: Fix sysfs mount instructions
  can-doc: Add hint about getting timestamps
  Fix CFQ I/O scheduler parameter name in documentation
  Documentation: arm: remove dead links from Marvell Berlin docs
  Documentation: HOWTO: update code cross reference link
  Doc: Docbook/iio: Fix typo in iio.tmpl
  DocBook: make index.html generation less verbose by default
  DocBook: Cleanup: remove an unused $(call) line
  DocBook: Add a help message for DOCBOOKS env var
  ...
2016-01-17 11:55:07 -08:00
Sergey Senozhatsky 06b031de22 printk: change recursion_bug type to bool
`recursion_bug' is used as recursion_bug toggle, so make it `bool'.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:31 -08:00
Andy Shevchenko 5b17aecfcd lib/vsprintf: factor out %pN[F] handler as netdev_bits()
Move switch case to the netdev_features_string() and rename it to
netdev_bits().  In the future we can extend it as needed.

Here we replace the fallback of %pN from '%p' with possible flags to
sticter '0x%p' without any flags variation.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:30 -08:00
Andy Shevchenko 3cab1e7112 lib/vsprintf: refactor duplicate code to special_hex_number()
special_hex_number() is a helper to print a fixed size type in a hex
format with '0x' prefix, zero padding, and small letters.  In the module
we have already several copies of such code.  Consolidate them under
special_hex_number() helper.

There are couple of differences though.

It seems nobody cared about the output in case of CONFIG_KALLSYMS=n,
when printing symbol address, because the asked field width is not
enough to care last 2 characters in the string represantation of the
pointer.  Fixed here.

The %pNF specifier used to be allowed with a specific field width,
though there is neither any user of it nor mention the possibility in
the documentation.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:30 -08:00
Rasmus Villemoes 64c734be70 printk-formats.txt: remove unimplemented %pT
%pT for task->comm has been proposed (several times, I think), but is
not actually implemented.  Remove it from printk-formats.txt and add it
back if/when it gets implemented.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:30 -08:00
Aaron Conole fe22cd9b7c printk: help pr_debug and pr_devel to optimize out arguments
Currently, pr_debug and pr_devel will not elide function call arguments
appearing in calls to the no_printk for these macros.  This is because
all side effects must be honored before proceeding to the 0-value
assignment in no_printk.

The behavior is contrary to documentation found in the CodingStyle and
the header file where these functions are declared.

This patch corrects that behavior by shunting out the call to no_printk
completely.  The format string is still checked by gcc for correctness,
but no code seems to be emitted in common cases.

[akpm@linux-foundation.org: remove braces, per Joe]
Fixes: 5264f2f75d ("include/linux/printk.h: use and neaten no_printk")
Signed-off-by: Aaron Conole <aconole@redhat.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Joe Perches <joe@perches.com>
Cc: Jason Baron <jbaron@akamai.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:29 -08:00
Rasmus Villemoes 251c723455 lib/test_printf.c: test dentry printing
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:29 -08:00
Rasmus Villemoes 857cca4d56 lib/test_printf.c: add test for large bitmaps
Following "lib/vsprintf.c: expand field_width to 24 bits", let's add a
test to see that we now actually support bitmaps with 65536 bits.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:29 -08:00
Rasmus Villemoes b79a7db37d lib/test_printf.c: account for kvasprintf tests
These should also count as performed tests.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:29 -08:00
Rasmus Villemoes 1ca8e8ebe9 lib/test_printf.c: add a few number() tests
This adds a few tests to test_number, one of which serves to document
another deviation from POSIX/C99 (printing 0 with an explicit precision
of 0).

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:28 -08:00
Rasmus Villemoes f176eb4ce9 lib/test_printf.c: test precision quirks
The kernel's printf doesn't follow the standards in a few corner cases
(which are probably mostly irrelevant).  Add tests that document the
current behaviour.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:28 -08:00
Rasmus Villemoes 331e4deb6d lib/test_printf.c: check for out-of-bound writes
Add a few padding bytes on either side of the test buffer, and check
that these (and the part of the buffer not used) are untouched by
vsnprintf.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:28 -08:00
Rasmus Villemoes fd0515d50f lib/test_printf.c: don't BUG
BUG is a completely unnecessarily big hammer, and we're more likely to
get the internal bug reported if we just pr_err() and ensure the test
suite fails.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:27 -08:00
Rasmus Villemoes 8e2a2bfdb8 lib/kasprintf.c: add sanity check to kvasprintf
kasprintf relies on being able to replay the formatting and getting the
same result (in particular, the same length).  This will almost always
work, but it is possible that the object pointed to by a %s or %p
argument changed under us (so we might get truncated output).  Add a
somewhat paranoid sanity check and let's see if it ever triggers.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:27 -08:00
Rasmus Villemoes 4d72ba014b lib/vsprintf.c: warn about too large precisions and field widths
The field width is overloaded to pass some extra information for some %p
extensions (e.g.  #bits for %pb).  But we might silently truncate the
passed value when we stash it in struct printf_spec (see e.g.
"lib/vsprintf.c: expand field_width to 24 bits").  Hopefully 23 value
bits should now be enough for everybody, but if not, let's make some
noise.

Do the same for the precision.  In both cases, clamping seems more
sensible than truncating.  While, according to POSIX, "A negative
precision is taken as if the precision were omitted.", the kernel's
printf has always treated that case as if the precision was 0, so we use
that as lower bound.  For the field width, the smallest representable
value is actually -(1<<23), but a negative field width means 'set the
LEFT flag and use the absolute value', so we want the absolute value to
fit.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:27 -08:00
Rasmus Villemoes 1c7a8e622e lib/vsprintf.c: help gcc make number() smaller
One consequence of the reorganization of struct printf_spec to make
field_width 24 bits was that number() gained about 180 bytes.  Since
spec is never passed to other functions, we can help gcc make number()
lose most of that extra weight by using local variables for the field
width and precision.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:26 -08:00
Rasmus Villemoes d048419311 lib/vsprintf.c: expand field_width to 24 bits
Maurizio Lombardi reported a problem [1] with the %pb extension: It
doesn't work for sufficiently large bitmaps, since the size is stashed
in the field_width field of the struct printf_spec, which is currently
an s16.  Concretely, this manifested itself in
/sys/bus/pseudo/drivers/scsi_debug/map being empty, since the bitmap
printer got a size of 0, which is the 16 bit truncation of the actual
bitmap size.

We do want to keep struct printf_spec at 8 bytes so that it can cheaply
be passed by value.  The qualifier field is only used for internal
bookkeeping in format_decode, so we might as well use a local variable
for that.  This gives us an additional 8 bits, which we can then use for
the field width.

To stay in 8 bytes, we need to do a little rearranging and make the type
member a bitfield as well.  For consistency, change all the members to
bit fields.  gcc doesn't generate much worse code with these changes (in
fact, bloat-o-meter says we save 300 bytes - which I think is a little
surprising).

I didn't find a BUILD_BUG/compiletime_assertion/... which would work
outside function context, so for now I just open-coded it.

[1] http://thread.gmane.org/gmane.linux.kernel/2034835

[akpm@linux-foundation.org: avoid open-coded BUILD_BUG_ON]
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reported-by: Maurizio Lombardi <mlombard@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:26 -08:00
Rasmus Villemoes 34fc8b9076 lib/vsprintf.c: eliminate potential race in string()
If the string corresponding to a %s specifier can change under us, we
might end up copying a \0 byte to the output buffer.  There might be
callers who expect the output buffer to contain a genuine C string whose
length is exactly the snprintf return value (assuming truncation hasn't
happened or has been checked for).

We can avoid this by only passing over the source string once, stopping
the first time we meet a nul byte (or when we reach the given
precision), and then letting widen_string() handle left/right space
padding.  As a small bonus, this code reuse also makes the generated
code slightly smaller.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:26 -08:00
Rasmus Villemoes 95508cfa10 lib/vsprintf.c: move string() below widen_string()
This is pure code movement, making sure the widen_string() helper is
defined before the string() function.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:26 -08:00
Rasmus Villemoes cfccde04e2 lib/vsprintf.c: pull out padding code from dentry_name()
Pull out the logic in dentry_name() which handles field width space
padding, in preparation for reusing it from string().  Rename the
widen() helper to move_right(), since it is used for handling the
!(flags & LEFT) case.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:25 -08:00
Tejun Heo 8d91f8b153 printk: do cond_resched() between lines while outputting to consoles
@console_may_schedule tracks whether console_sem was acquired through
lock or trylock.  If the former, we're inside a sleepable context and
console_conditional_schedule() performs cond_resched().  This allows
console drivers which use console_lock for synchronization to yield
while performing time-consuming operations such as scrolling.

However, the actual console outputting is performed while holding
irq-safe logbuf_lock, so console_unlock() clears @console_may_schedule
before starting outputting lines.  Also, only a few drivers call
console_conditional_schedule() to begin with.  This means that when a
lot of lines need to be output by console_unlock(), for example on a
console registration, the task doing console_unlock() may not yield for
a long time on a non-preemptible kernel.

If this happens with a slow console devices, for example a serial
console, the outputting task may occupy the cpu for a very long time.
Long enough to trigger softlockup and/or RCU stall warnings, which in
turn pile more messages, sometimes enough to trigger the next cycle of
warnings incapacitating the system.

Fix it by making console_unlock() insert cond_resched() between lines if
@console_may_schedule.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Calvin Owens <calvinowens@fb.com>
Acked-by: Jan Kara <jack@suse.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Kyle McMartin <kyle@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:25 -08:00