Commit Graph

5774 Commits

Author SHA1 Message Date
Amos Kong
f49819560f virtio-rng: skip reading when we start to remove the device
Before we really unregister the hwrng device, reading will get stuck if
the virtio device is reset. We should return error for reading when we
start to remove the device.

Signed-off-by: Amos Kong <akong@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-09-11 22:28:38 +09:30
Amos Kong
3856e54837 virtio-rng: fix stuck of hot-unplugging busy device
When we try to hot-remove a busy virtio-rng device from QEMU monitor,
the device can't be hot-removed. Because virtio-rng driver hangs at
wait_for_completion_killable().

This patch exits the waiting by completing have_data completion before
unregistering, resets data_avail to avoid the hwrng core use wrong
buffer bytes.

Signed-off-by: Amos Kong <akong@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-09-11 22:28:34 +09:30
Amit Shah
34679ec7a0 virtio: rng: add derating factor for use by hwrng core
The khwrngd thread is started when a hwrng device of sufficient
quality is registered.  The virtio-rng device is backed by the
hypervisor, and we trust the hypervisor to provide real entropy.

A malicious or badly-implemented hypervisor is a scenario that's
irrelevant -- such a setup is bound to cause all sorts of badness, and a
compromised hwrng is the least of the user's worries.

Given this, we might as well assume that the quality of randomness we
receive is perfectly trustworthy.  Hence, we use 100% for the factor,
indicating maximum confidence in the source.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: H. Peter Anvin <hpa@linux.intel.com>
Reviewed-by: Amos Kong <akong@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-08-15 10:26:01 +05:30
Linus Torvalds
801a71a858 Cheers,
Rusty.
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Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull virtio updates from Rusty Russell.

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  Revert "hwrng: virtio - ensure reads happen after successful probe"
  virtio: rng: delay hwrng_register() till driver is ready
  virtio: rng: re-arrange struct elements for better packing
  virtio: rng: remove unused struct element
  virtio: Replace DEFINE_PCI_DEVICE_TABLE macro use
  virtio: console: remove unnecessary null test before debugfs_remove_recursive
2014-08-10 21:31:04 -07:00
Linus Torvalds
a7d7a143d0 Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
Pull DRM updates from Dave Airlie:
 "Like all good pull reqs this ends with a revert, so it must mean we
  tested it,

[ Ed. That's _one_ way of looking at it ]

  This pull is missing nouveau, Ben has been stuck trying to track down
  a very longstanding bug that revealed itself due to some other
  changes.  I've asked him to send you a direct pull request for nouveau
  once he cleans things up.  I'm away until Monday so don't want to
  delay things, you can make a decision on that when he sends it, I have
  my phone so I can ack things just not really merge much.

  It has one trivial conflict with your tree in armada_drv.c, and also
  the pull request contains some component changes that are already in
  your tree, the base tree from Russell went via Greg's tree already,
  but some stuff still shows up in here that doesn't when I merge my
  tree into yours.

  Otherwise all pretty standard graphics fare, one new driver and
  changes all over the place.

  New drivers:
   - sti kms driver for STMicroelectronics chipsets stih416 and stih407.

  core:
   - lots of cleanups to the drm core
   - DP MST helper code merged
   - universal cursor planes.
   - render nodes enabled by default

  panel:
   - better panel interfaces
   - new panel support
   - non-continuous cock advertising ability

  ttm:
   - shrinker fixes

  i915:
   - hopefully ditched UMS support
   - runtime pm fixes
   - psr tracking and locking - now enabled by default
   - userptr fixes
   - backlight brightness fixes
   - MST support merged
   - runtime PM for dpms
   - primary planes locking fixes
   - gen8 hw semaphore support
   - fbc fixes
   - runtime PM on SOix sleep state hw.
   - mmio base page flipping
   - lots of vlv/chv fixes.
   - universal cursor planes

  radeon:
   - Hawaii fixes
   - display scalar support for non-fixed mode displays
   - new firmware format support
   - dpm on more asics by default
   - GPUVM improvements
   - uncached and wc GTT buffers
   - BOs > visible VRAM

  exynos:
   - i80 interface support
   - module auto-loading
   - ipp driver consolidated.

  armada:
   - irq handling in crtc layer only
   - crtc renumbering
   - add component support
   - DT interaction changes.

  tegra:
   - load as module fixes
   - eDP bpp and sync polarity fixed
   - DSI non-continuous clock mode support
   - better support for importing buffers from nouveau

  msm:
   - mdp5/adq8084 v1.3 hw enablement
   - devicetree clk changse
   - ifc6410 board working

  tda998x:
   - component support
   - DT documentation update

  vmwgfx:
   - fix compat shader namespace"

* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (551 commits)
  Revert "drm: drop redundant drm_file->is_master"
  drm/panel: simple: Use devm_gpiod_get_optional()
  drm/dsi: Replace upcasting macro by function
  drm/panel: ld9040: Replace upcasting macro by function
  drm/exynos: dp: Modify driver to support drm_panel
  drm/exynos: Move DP setup into commit()
  drm/panel: simple: Add AUO B133HTN01 panel support
  drm/panel: simple: Support delays in panel functions
  drm/panel: simple: Add proper definition for prepare and unprepare
  drm/panel: s6e8aa0: Add proper definition for prepare and unprepare
  drm/panel: ld9040: Add proper definition for prepare and unprepare
  drm/tegra: Add support for panel prepare and unprepare routines
  drm/exynos: dsi: Add support for panel prepare and unprepare routines
  drm/exynos: dpi: Add support for panel prepare and unprepare routines
  drm/panel: simple: Add dummy prepare and unprepare routines
  drm/panel: s6e8aa0: Add dummy prepare and unprepare routines
  drm/panel: ld9040: Add dummy prepare and unprepare routines
  drm/panel: Provide convenience wrapper for .get_modes()
  drm/panel: add .prepare() and .unprepare() functions
  drm/panel: simple: Remove simple-panel compatible
  ...
2014-08-07 17:36:12 -07:00
Linus Torvalds
f4f142ed4e Cleanups and bug fixes to /dev/random, add a new getrandom(2) system
call, which is a superset of OpenBSD's getentropy(2) call, for use
 with userspace crypto libraries such as LibreSSL.  Also add the
 ability to have a kernel thread to pull entropy from hardware rng
 devices into /dev/random.
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Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random

Pull randomness updates from Ted Ts'o:
 "Cleanups and bug fixes to /dev/random, add a new getrandom(2) system
  call, which is a superset of OpenBSD's getentropy(2) call, for use
  with userspace crypto libraries such as LibreSSL.

  Also add the ability to have a kernel thread to pull entropy from
  hardware rng devices into /dev/random"

* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
  hwrng: Pass entropy to add_hwgenerator_randomness() in bits, not bytes
  random: limit the contribution of the hw rng to at most half
  random: introduce getrandom(2) system call
  hw_random: fix sparse warning (NULL vs 0 for pointer)
  random: use registers from interrupted code for CPU's w/o a cycle counter
  hwrng: add per-device entropy derating
  hwrng: create filler thread
  random: add_hwgenerator_randomness() for feeding entropy from devices
  random: use an improved fast_mix() function
  random: clean up interrupt entropy accounting for archs w/o cycle counters
  random: only update the last_pulled time if we actually transferred entropy
  random: remove unneeded hash of a portion of the entropy pool
  random: always update the entropy pool under the spinlock
2014-08-06 08:16:24 -07:00
Linus Torvalds
bb2cbf5e93 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "In this release:

   - PKCS#7 parser for the key management subsystem from David Howells
   - appoint Kees Cook as seccomp maintainer
   - bugfixes and general maintenance across the subsystem"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (94 commits)
  X.509: Need to export x509_request_asymmetric_key()
  netlabel: shorter names for the NetLabel catmap funcs/structs
  netlabel: fix the catmap walking functions
  netlabel: fix the horribly broken catmap functions
  netlabel: fix a problem when setting bits below the previously lowest bit
  PKCS#7: X.509 certificate issuer and subject are mandatory fields in the ASN.1
  tpm: simplify code by using %*phN specifier
  tpm: Provide a generic means to override the chip returned timeouts
  tpm: missing tpm_chip_put in tpm_get_random()
  tpm: Properly clean sysfs entries in error path
  tpm: Add missing tpm_do_selftest to ST33 I2C driver
  PKCS#7: Use x509_request_asymmetric_key()
  Revert "selinux: fix the default socket labeling in sock_graft()"
  X.509: x509_request_asymmetric_keys() doesn't need string length arguments
  PKCS#7: fix sparse non static symbol warning
  KEYS: revert encrypted key change
  ima: add support for measuring and appraising firmware
  firmware_class: perform new LSM checks
  security: introduce kernel_fw_from_file hook
  PKCS#7: Missing inclusion of linux/err.h
  ...
2014-08-06 08:06:39 -07:00
Linus Torvalds
e7fda6c4c3 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer and time updates from Thomas Gleixner:
 "A rather large update of timers, timekeeping & co

   - Core timekeeping code is year-2038 safe now for 32bit machines.
     Now we just need to fix all in kernel users and the gazillion of
     user space interfaces which rely on timespec/timeval :)

   - Better cache layout for the timekeeping internal data structures.

   - Proper nanosecond based interfaces for in kernel users.

   - Tree wide cleanup of code which wants nanoseconds but does hoops
     and loops to convert back and forth from timespecs.  Some of it
     definitely belongs into the ugly code museum.

   - Consolidation of the timekeeping interface zoo.

   - A fast NMI safe accessor to clock monotonic for tracing.  This is a
     long standing request to support correlated user/kernel space
     traces.  With proper NTP frequency correction it's also suitable
     for correlation of traces accross separate machines.

   - Checkpoint/restart support for timerfd.

   - A few NOHZ[_FULL] improvements in the [hr]timer code.

   - Code move from kernel to kernel/time of all time* related code.

   - New clocksource/event drivers from the ARM universe.  I'm really
     impressed that despite an architected timer in the newer chips SoC
     manufacturers insist on inventing new and differently broken SoC
     specific timers.

[ Ed. "Impressed"? I don't think that word means what you think it means ]

   - Another round of code move from arch to drivers.  Looks like most
     of the legacy mess in ARM regarding timers is sorted out except for
     a few obnoxious strongholds.

   - The usual updates and fixlets all over the place"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (114 commits)
  timekeeping: Fixup typo in update_vsyscall_old definition
  clocksource: document some basic timekeeping concepts
  timekeeping: Use cached ntp_tick_length when accumulating error
  timekeeping: Rework frequency adjustments to work better w/ nohz
  timekeeping: Minor fixup for timespec64->timespec assignment
  ftrace: Provide trace clocks monotonic
  timekeeping: Provide fast and NMI safe access to CLOCK_MONOTONIC
  seqcount: Add raw_write_seqcount_latch()
  seqcount: Provide raw_read_seqcount()
  timekeeping: Use tk_read_base as argument for timekeeping_get_ns()
  timekeeping: Create struct tk_read_base and use it in struct timekeeper
  timekeeping: Restructure the timekeeper some more
  clocksource: Get rid of cycle_last
  clocksource: Move cycle_last validation to core code
  clocksource: Make delta calculation a function
  wireless: ath9k: Get rid of timespec conversions
  drm: vmwgfx: Use nsec based interfaces
  drm: i915: Use nsec based interfaces
  timekeeping: Provide ktime_get_raw()
  hangcheck-timer: Use ktime_get_ns()
  ...
2014-08-05 17:46:42 -07:00
Stephen Boyd
e02b876597 hwrng: Pass entropy to add_hwgenerator_randomness() in bits, not bytes
rng_get_data() returns the number of bytes read from the hardware.
The entropy argument to add_hwgenerator_randomness() is passed
directly to credit_entropy_bits() so we should be passing the
number of bits, not bytes here.

Fixes: be4000bc46 "hwrng: create filler thread"
Acked-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-05 16:50:10 -04:00
Theodore Ts'o
48d6be955a random: limit the contribution of the hw rng to at most half
For people who don't trust a hardware RNG which can not be audited,
the changes to add support for RDSEED can be troubling since 97% or
more of the entropy will be contributed from the in-CPU hardware RNG.

We now have a in-kernel khwrngd, so for those people who do want to
implicitly trust the CPU-based system, we could create an arch-rng
hw_random driver, and allow khwrng refill the entropy pool.  This
allows system administrator whether or not they trust the CPU (I
assume the NSA will trust RDRAND/RDSEED implicitly :-), and if so,
what level of entropy derating they want to use.

The reason why this is a really good idea is that if different people
use different levels of entropy derating, it will make it much more
difficult to design a backdoor'ed hwrng that can be generally
exploited in terms of the output of /dev/random when different attack
targets are using differing levels of entropy derating.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-05 16:41:50 -04:00
Theodore Ts'o
c6e9d6f388 random: introduce getrandom(2) system call
The getrandom(2) system call was requested by the LibreSSL Portable
developers.  It is analoguous to the getentropy(2) system call in
OpenBSD.

The rationale of this system call is to provide resiliance against
file descriptor exhaustion attacks, where the attacker consumes all
available file descriptors, forcing the use of the fallback code where
/dev/[u]random is not available.  Since the fallback code is often not
well-tested, it is better to eliminate this potential failure mode
entirely.

The other feature provided by this new system call is the ability to
request randomness from the /dev/urandom entropy pool, but to block
until at least 128 bits of entropy has been accumulated in the
/dev/urandom entropy pool.  Historically, the emphasis in the
/dev/urandom development has been to ensure that urandom pool is
initialized as quickly as possible after system boot, and preferably
before the init scripts start execution.

This is because changing /dev/urandom reads to block represents an
interface change that could potentially break userspace which is not
acceptable.  In practice, on most x86 desktop and server systems, in
general the entropy pool can be initialized before it is needed (and
in modern kernels, we will printk a warning message if not).  However,
on an embedded system, this may not be the case.  And so with this new
interface, we can provide the functionality of blocking until the
urandom pool has been initialized.  Any userspace program which uses
this new functionality must take care to assure that if it is used
during the boot process, that it will not cause the init scripts or
other portions of the system startup to hang indefinitely.

SYNOPSIS
	#include <linux/random.h>

	int getrandom(void *buf, size_t buflen, unsigned int flags);

DESCRIPTION
	The system call getrandom() fills the buffer pointed to by buf
	with up to buflen random bytes which can be used to seed user
	space random number generators (i.e., DRBG's) or for other
	cryptographic uses.  It should not be used for Monte Carlo
	simulations or other programs/algorithms which are doing
	probabilistic sampling.

	If the GRND_RANDOM flags bit is set, then draw from the
	/dev/random pool instead of the /dev/urandom pool.  The
	/dev/random pool is limited based on the entropy that can be
	obtained from environmental noise, so if there is insufficient
	entropy, the requested number of bytes may not be returned.
	If there is no entropy available at all, getrandom(2) will
	either block, or return an error with errno set to EAGAIN if
	the GRND_NONBLOCK bit is set in flags.

	If the GRND_RANDOM bit is not set, then the /dev/urandom pool
	will be used.  Unlike using read(2) to fetch data from
	/dev/urandom, if the urandom pool has not been sufficiently
	initialized, getrandom(2) will block (or return -1 with the
	errno set to EAGAIN if the GRND_NONBLOCK bit is set in flags).

	The getentropy(2) system call in OpenBSD can be emulated using
	the following function:

            int getentropy(void *buf, size_t buflen)
            {
                    int     ret;

                    if (buflen > 256)
                            goto failure;
                    ret = getrandom(buf, buflen, 0);
                    if (ret < 0)
                            return ret;
                    if (ret == buflen)
                            return 0;
            failure:
                    errno = EIO;
                    return -1;
            }

RETURN VALUE
       On success, the number of bytes that was filled in the buf is
       returned.  This may not be all the bytes requested by the
       caller via buflen if insufficient entropy was present in the
       /dev/random pool, or if the system call was interrupted by a
       signal.

       On error, -1 is returned, and errno is set appropriately.

ERRORS
	EINVAL		An invalid flag was passed to getrandom(2)

	EFAULT		buf is outside the accessible address space.

	EAGAIN		The requested entropy was not available, and
			getentropy(2) would have blocked if the
			GRND_NONBLOCK flag was not set.

	EINTR		While blocked waiting for entropy, the call was
			interrupted by a signal handler; see the description
			of how interrupted read(2) calls on "slow" devices
			are handled with and without the SA_RESTART flag
			in the signal(7) man page.

NOTES
	For small requests (buflen <= 256) getrandom(2) will not
	return EINTR when reading from the urandom pool once the
	entropy pool has been initialized, and it will return all of
	the bytes that have been requested.  This is the recommended
	way to use getrandom(2), and is designed for compatibility
	with OpenBSD's getentropy() system call.

	However, if you are using GRND_RANDOM, then getrandom(2) may
	block until the entropy accounting determines that sufficient
	environmental noise has been gathered such that getrandom(2)
	will be operating as a NRBG instead of a DRBG for those people
	who are working in the NIST SP 800-90 regime.  Since it may
	block for a long time, these guarantees do *not* apply.  The
	user may want to interrupt a hanging process using a signal,
	so blocking until all of the requested bytes are returned
	would be unfriendly.

	For this reason, the user of getrandom(2) MUST always check
	the return value, in case it returns some error, or if fewer
	bytes than requested was returned.  In the case of
	!GRND_RANDOM and small request, the latter should never
	happen, but the careful userspace code (and all crypto code
	should be careful) should check for this anyway!

	Finally, unless you are doing long-term key generation (and
	perhaps not even then), you probably shouldn't be using
	GRND_RANDOM.  The cryptographic algorithms used for
	/dev/urandom are quite conservative, and so should be
	sufficient for all purposes.  The disadvantage of GRND_RANDOM
	is that it can block, and the increased complexity required to
	deal with partially fulfilled getrandom(2) requests.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Zach Brown <zab@zabbo.net>
2014-08-05 16:41:22 -04:00
Linus Torvalds
79eb238c76 TTY / Serial driver update for 3.17-rc1
Here's the big tty / serial driver update for 3.17-rc1.
 
 Nothing major, just a number of fixes and new features for different
 serial drivers, and some more tty core fixes and documentation of the
 tty locks.
 
 All of these have been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty / serial driver update from Greg KH:
 "Here's the big tty / serial driver update for 3.17-rc1.

  Nothing major, just a number of fixes and new features for different
  serial drivers, and some more tty core fixes and documentation of the
  tty locks.

  All of these have been in linux-next for a while"

* tag 'tty-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (82 commits)
  tty/n_gsm.c: fix a memory leak in gsmld_open
  pch_uart: don't hardcode PCI slot to get DMA device
  tty: n_gsm, use setup_timer
  Revert "ARC: [arcfpga] stdout-path now suffices for earlycon/console"
  serial: sc16is7xx: Correct initialization of s->clk
  serial: 8250_dw: Add support for deferred probing
  serial: 8250_dw: Add optional reset control support
  serial: st-asc: Fix overflow in baudrate calculation
  serial: st-asc: Don't call BUG in asc_console_setup()
  tty: serial: msm: Make of_device_id array const
  tty/n_gsm.c: get gsm->num after gsm_activate_mux
  serial/core: Fix too big allocation for attribute member
  drivers/tty/serial: use correct type for dma_map/unmap
  serial: altera_jtaguart: Fix putchar function passed to uart_console_write()
  serial/uart/8250: Add tunable RX interrupt trigger I/F of FIFO buffers
  Serial: allow port drivers to have a default attribute group
  tty: kgdb_nmi: Automatically manage tty enable
  serial: altera_jtaguart: Adpot uart_console_write()
  serial: samsung: improve code clarity by defining a variable
  serial: samsung: correct the case and default order in switch
  ...
2014-08-04 18:51:19 -07:00
Linus Torvalds
2521129a6d Char / Misc driver patches for 3.17-rc1
Here's the big driver misc / char pull request for 3.17-rc1.
 
 Lots of things in here, the thunderbolt support for Apple laptops, some
 other new drivers, testing fixes, and other good things.  All have been
 in linux-next for a long time.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char / misc driver patches from Greg KH:
 "Here's the big driver misc / char pull request for 3.17-rc1.

  Lots of things in here, the thunderbolt support for Apple laptops,
  some other new drivers, testing fixes, and other good things.  All
  have been in linux-next for a long time"

* tag 'char-misc-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (119 commits)
  misc: bh1780: Introduce the use of devm_kzalloc
  Lattice ECP3 FPGA: Correct endianness
  drivers/misc/ti-st: Load firmware from ti-connectivity directory.
  dt-bindings: extcon: Add support for SM5502 MUIC device
  extcon: sm5502: Change internal hardware switch according to cable type
  extcon: sm5502: Detect cable state after completing platform booting
  extcon: sm5502: Add support new SM5502 extcon device driver
  extcon: arizona: Get MICVDD against extcon device
  extcon: Remove unnecessary OOM messages
  misc: vexpress: Fix sparse non static symbol warnings
  mei: drop unused hw dependent fw status functions
  misc: bh1770glc: Use managed functions
  pcmcia: remove DEFINE_PCI_DEVICE_TABLE usage
  misc: remove DEFINE_PCI_DEVICE_TABLE usage
  ipack: Replace DEFINE_PCI_DEVICE_TABLE macro use
  drivers/char/dsp56k.c: drop check for negativity of unsigned parameter
  mei: fix return value on disconnect timeout
  mei: don't schedule suspend in pm idle
  mei: start disconnect request timer consistently
  mei: reset client connection state on timeout
  ...
2014-08-04 17:32:24 -07:00
Dave Airlie
5d42f82a9b Linux 3.16
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Merge tag 'v3.16' into drm-next

Linux 3.16

backmerge requested by i915, nouveau and radeon authors

Conflicts:
	drivers/gpu/drm/i915/i915_gem_render_state.c
	drivers/gpu/drm/i915/intel_drv.h
2014-08-05 09:04:59 +10:00
Mathias Krause
08d645c181 agp: remove read/write stubs
The VFS layer handles those in the very same way, if unset. No need for
additional stubs.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-08-02 06:43:51 +10:00
Andy Shevchenko
a3d64df849 tpm: simplify code by using %*phN specifier
Instead of looping by ourselves we may use %*phN specifier to dump a small
buffer.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
[ PHuewe: removed now unused variable i ]
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-07-29 23:10:56 +02:00
Jason Gunthorpe
8e54caf407 tpm: Provide a generic means to override the chip returned timeouts
Some Atmel TPMs provide completely wrong timeouts from their
TPM_CAP_PROP_TIS_TIMEOUT query. This patch detects that and returns
new correct values via a DID/VID table in the TIS driver.

Tested on ARM using an AT97SC3204T FW version 37.16

Cc: <stable@vger.kernel.org>
[PHuewe: without this fix these 'broken' Atmel TPMs won't function on
older kernels]
Signed-off-by: "Berg, Christopher" <Christopher.Berg@atmel.com>
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-07-29 23:10:56 +02:00
Jarkko Sakkinen
3e14d83ef9 tpm: missing tpm_chip_put in tpm_get_random()
Regression in 41ab999c. Call to tpm_chip_put is missing. This
will cause TPM device driver not to unload if tmp_get_random()
is called.

Cc: <stable@vger.kernel.org> # 3.7+
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-07-29 23:10:55 +02:00
Stefan Berger
b49e1043c4 tpm: Properly clean sysfs entries in error path
Properly clean the sysfs entries in the error path

Cc: <stable@vger.kernel.org>
Reported-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-07-29 23:10:55 +02:00
Jason Gunthorpe
f07a5e9a33 tpm: Add missing tpm_do_selftest to ST33 I2C driver
Most device drivers do call 'tpm_do_selftest' which executes a
TPM_ContinueSelfTest. tpm_i2c_stm_st33 is just pointlessly different,
I think it is bug.

These days we have the general assumption that the TPM is usable by
the kernel immediately after the driver is finished, so we can no
longer defer the mandatory self test to userspace.

Cc: <stable@vger.kernel.org> # 3.12+
Reported-by: Richard Marciel <rmaciel@linux.vnet.ibm.com>
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-07-29 23:10:55 +02:00
Amit Shah
eeec626366 Revert "hwrng: virtio - ensure reads happen after successful probe"
This reverts commit e052dbf554.

Now that we use the virtio ->scan() function to register with the hwrng
core, we will not get read requests till probe is successfully finished.

So revert the workaround we had in place to refuse read requests while
we were not yet setup completely.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-07-27 21:07:20 +09:30
Amit Shah
5c06273401 virtio: rng: delay hwrng_register() till driver is ready
Instead of calling hwrng_register() in the probe routing, call it in the
scan routine.  This ensures that when hwrng_register() is successful,
and it requests a few random bytes to seed the kernel's pool at init,
we're ready to service that request.

This will also enable us to remove the workaround added previously to
check whether probe was completed, and only then ask for data from the
host.  The revert follows in the next commit.

There's a slight behaviour change here on unsuccessful hwrng_register().
Previously, when hwrng_register() failed, the probe() routine would
fail, and the vqs would be torn down, and driver would be marked not
initialized.  Now, the vqs will remain initialized, driver would be
marked initialized as well, but won't be available in the list of RNGs
available to hwrng core.  To fix the failures, the procedure remains the
same, i.e. unload and re-load the module, and hope things succeed the
next time around.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-07-27 21:07:19 +09:30
Amit Shah
6062829fcd virtio: rng: re-arrange struct elements for better packing
Re-arrange the elements of the virtrng_info struct to pack it better.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-07-27 21:07:18 +09:30
Amit Shah
373445d02b virtio: rng: remove unused struct element
vdev is unused in struct virtrng_info, remove it.

CC: Amos Kong <akong@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-07-27 21:07:17 +09:30
Fabian Frederick
5885e48e44 virtio: console: remove unnecessary null test before debugfs_remove_recursive
Fix checkpatch warning:
WARNING: debugfs_remove_recursive(NULL) is safe this check is probably not required

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: virtualization@lists.linux-foundation.org
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-07-27 21:07:14 +09:30
Thomas Gleixner
2044fdb03e hangcheck-timer: Use ktime_get_ns()
There is no point in having a S390 private implementation and there is
no point in using the raw monotonic time. The NTP freqeuency
adjustment of CLOCK_MONOTONIC is really not doing any harm for the
hang check timer.

Use ktime_get_ns() for everything and get rid of the timespec
conversions.

V2: Drop the raw monotonic and the S390 special case

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-07-23 15:01:49 -07:00
Linus Torvalds
b8d2d12804 Fix a BUG splat found by trinity.
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Merge tag 'random_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random

Pull /dev/random fix from Ted Ts'o:
 "Fix a BUG splat found by trinity"

* tag 'random_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
  random: check for increase of entropy_count because of signed conversion
2014-07-18 20:26:46 -10:00
Linus Torvalds
4e10627529 Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fixes from Herbert Xu:
 "This push fixes a boot hang in virt guests when the virtio RNG is
  enabled"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  hwrng: virtio - ensure reads happen after successful probe
  hwrng: fetch randomness only after device init
2014-07-18 20:25:54 -10:00
Hannes Frederic Sowa
79a8468747 random: check for increase of entropy_count because of signed conversion
The expression entropy_count -= ibytes << (ENTROPY_SHIFT + 3) could
actually increase entropy_count if during assignment of the unsigned
expression on the RHS (mind the -=) we reduce the value modulo
2^width(int) and assign it to entropy_count. Trinity found this.

[ Commit modified by tytso to add an additional safety check for a
  negative entropy_count -- which should never happen, and to also add
  an additional paranoia check to prevent overly large count values to
  be passed into urandom_read().  ]

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-07-19 01:42:13 -04:00
Andrey Utkin
389345cf6d drivers/char/dsp56k.c: drop check for negativity of unsigned parameter
[linux-3.16-rc5/drivers/char/dsp56k.c:386]: (style) Checking if unsigned
variable 'arg' is less than zero.

Source code is

            if (arg > 31 || arg < 0)
                return -EINVAL;

But

static long dsp56k_ioctl(struct file *file, unsigned int cmd,
             unsigned long arg)

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=80411
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Andrey Utkin <andrey.krieger.utkin@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-17 18:38:37 -07:00
Torsten Duwe
9dda727d37 hw_random: fix sparse warning (NULL vs 0 for pointer)
Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-15 04:49:41 -04:00
Theodore Ts'o
ee3e00e9e7 random: use registers from interrupted code for CPU's w/o a cycle counter
For CPU's that don't have a cycle counter, or something equivalent
which can be used for random_get_entropy(), random_get_entropy() will
always return 0.  In that case, substitute with the saved interrupt
registers to add a bit more unpredictability.

Some folks have suggested hashing all of the registers
unconditionally, but this would increase the overhead of
add_interrupt_randomness() by at least an order of magnitude, and this
would very likely be unacceptable.

The changes in this commit have been benchmarked as mostly unaffecting
the overhead of add_interrupt_randomness() if the entropy counter is
present, and doubling the overhead if it is not present.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Jörn Engel <joern@logfs.org>
2014-07-15 04:49:41 -04:00
Torsten Duwe
0f734e6e76 hwrng: add per-device entropy derating
This patch introduces a derating factor to struct hwrng for
the random bits going into the kernel input pool, and a common
default derating for drivers which do not specify one.

Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Acked-by: H. Peter Anvin <hpa@zytor.com>
2014-07-15 04:49:40 -04:00
Torsten Duwe
be4000bc46 hwrng: create filler thread
This can be viewed as the in-kernel equivalent of hwrngd;
like FUSE it is a good thing to have a mechanism in user land,
but for some reasons (simplicity, secrecy, integrity, speed)
it may be better to have it in kernel space.

This patch creates a thread once a hwrng registers, and uses
the previously established add_hwgenerator_randomness() to feed
its data to the input pool as long as needed. A derating factor
is used to bias the entropy estimation and to disable this
mechanism entirely when set to zero.

Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Acked-by: H. Peter Anvin <hpa@zytor.com>
2014-07-15 04:49:40 -04:00
Torsten Duwe
c84dbf61a7 random: add_hwgenerator_randomness() for feeding entropy from devices
This patch adds an interface to the random pool for feeding entropy
in-kernel.

Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Acked-by: H. Peter Anvin <hpa@zytor.com>
2014-07-15 04:49:40 -04:00
Theodore Ts'o
43759d4f42 random: use an improved fast_mix() function
Use more efficient fast_mix() function.  Thanks to George Spelvin for
doing the leg work to find a more efficient mixing function.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: George Spelvin <linux@horizon.com>
2014-07-15 04:49:40 -04:00
Theodore Ts'o
840f95077f random: clean up interrupt entropy accounting for archs w/o cycle counters
For architectures that don't have cycle counters, the algorithm for
deciding when to avoid giving entropy credit due to back-to-back timer
interrupts didn't make any sense, since we were checking every 64
interrupts.  Change it so that we only give an entropy credit if the
majority of the interrupts are not based on the timer.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: George Spelvin <linux@horizon.com>
2014-07-15 04:49:39 -04:00
Theodore Ts'o
cff850312c random: only update the last_pulled time if we actually transferred entropy
In xfer_secondary_pull(), check to make sure we need to pull from the
secondary pool before checking and potentially updating the
last_pulled time.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: George Spelvin <linux@horizon.com>
2014-07-15 04:49:39 -04:00
Theodore Ts'o
85608f8e16 random: remove unneeded hash of a portion of the entropy pool
We previously extracted a portion of the entropy pool in
mix_pool_bytes() and hashed it in to avoid racing CPU's from returning
duplicate random values.  Now that we are using a spinlock to prevent
this from happening, this is no longer necessary.  So remove it, to
simplify the code a bit.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: George Spelvin <linux@horizon.com>
2014-07-15 04:49:39 -04:00
Theodore Ts'o
91fcb532ef random: always update the entropy pool under the spinlock
Instead of using lockless techniques introduced in commit
902c098a36, use spin_trylock to try to grab entropy pool's lock.  If
we can't get the lock, then just try again on the next interrupt.

Based on discussions with George Spelvin.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: George Spelvin <linux@horizon.com>
2014-07-15 04:49:39 -04:00
Amit Shah
e052dbf554 hwrng: virtio - ensure reads happen after successful probe
The hwrng core asks for random data in the hwrng_register() call itself
from commit d9e7972619.  This doesn't play well with virtio -- the
DRIVER_OK bit is only set by virtio core on a successful probe, and
we're not yet out of our probe routine when this call is made.  This
causes the host to not acknowledge any requests we put in the virtqueue,
and the insmod or kernel boot process just waits for data to arrive from
the host, which never happens.

CC: Kees Cook <keescook@chromium.org>
CC: Jason Cooper <jason@lakedaemon.net>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: <stable@vger.kernel.org> # For v3.15+
Reviewed-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-07-14 20:48:17 +08:00
Amit Shah
d3cc799647 hwrng: fetch randomness only after device init
Commit d9e7972619 "hwrng: add randomness to system from rng sources"
added a call to rng_get_data() from the hwrng_register() function.
However, some rng devices need initialization before data can be read
from them.

This commit makes the call to rng_get_data() depend on no init fn
pointer being registered by the device.  If an init function is
registered, this call is made after device init.

CC: Kees Cook <keescook@chromium.org>
CC: Jason Cooper <jason@lakedaemon.net>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: <stable@vger.kernel.org> # For v3.15+
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-07-14 20:48:17 +08:00
Greg Kroah-Hartman
ca17749259 Merge 3.16-rc5 into tty-next.
We want those fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-13 15:52:12 -07:00
Greg Kroah-Hartman
9f48c89862 Merge 3.16-rc5 into char-misc-next
This resolves a number of merge issues with changes in this tree and
Linus's tree at the same time.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-13 15:26:47 -07:00
Peter Hurley
69fee6885f char: synclink: Remove WARN_ON for bad port count
tty_port_close_start() already validates the port counts and issues
a diagnostic if validation fails.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-10 16:07:46 -07:00
Peter Hurley
e359a4e38d tty: Remove tty_hung_up_p() tests from tty drivers' open()
Since at least before 2.6.30, it has not been possible to observe
a hung up file pointer in a tty driver's open() method unless/until
the driver open() releases the tty_lock() (eg., before blocking).

This is because tty_open() adds the file pointer while holding
the tty_lock() _and_ doesn't release the lock until after calling
the tty driver's open() method. [ Before tty_lock(), this was
lock_kernel(). ]

Since __tty_hangup() first waits on the tty_lock() before
enumerating and hanging up the open file pointers, either
__tty_hangup() will wait for the tty_lock() or tty_open() will
not yet have added the file pointer. For example,

CPU 0                          |  CPU 1
                               |
tty_open                       |  __tty_hangup
  ..                           |    ..
  tty_lock                     |    ..
  tty_reopen                   |    tty_lock  / blocks
  ..                           |
  tty_add_file(tty, filp)      |
  ..                           |
  tty->ops->open(tty, filp)    |
    tty_port_open              |
      tty_port_block_til_ready |
        ..                     |
        while (1)              |
          ..                   |
          tty_unlock           |    / unblocks
          schedule             |    for each filp on tty->tty_files
                               |      f_ops = tty_hung_up_fops;
                               |    ..
                               |    tty_unlock
          tty_lock             |
  ..                           |
  tty_unlock                   |

Note that since tty_port_block_til_ready() and similar drop
the tty_lock while blocking, when woken, the file pointer
must then be tested for having been hung up.

Also, fix bit-rotted drivers that used extra_count to track the
port->count bump.

CC: Mikael Starvik <starvik@axis.com>
CC: Samuel Ortiz <samuel@sortiz.org>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-10 16:06:49 -07:00
Dan Carpenter
8a26af30ff char: xilinx_hwicap: missing error code if ioremap() fails
Return -ENOMEM instead of success if ioremap() fails.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-09 16:59:58 -07:00
Kees Cook
4171ee9e3c bsr: avoid format string leaking into device name
This makes sure a format string cannot accidentally leak into a device name.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-09 16:59:15 -07:00
Guenter Roeck
6d827fbcc3 i8k: Fix non-SMP operation
Commit f36fdb9f02 (i8k: Force SMM to run on CPU 0) adds support
for multi-core CPUs to the driver. Unfortunately, that causes it
to fail loading if compiled without SMP support, at least on
32 bit kernels. Kernel log shows "i8k: unable to get SMM Dell
signature", and function i8k_smm is found to return -EINVAL.

Testing revealed that the culprit is the missing return value check
of set_cpus_allowed_ptr.

Fixes: f36fdb9f02 (i8k: Force SMM to run on CPU 0)
Reported-by: Jim Bos <jim876@xs4all.nl>
Tested-by: Jim Bos <jim876@xs4all.nl>
Cc: stable@vger.kernel.org # 3.14+
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: Andreas Mohr <andi@lisas.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-09 16:45:36 -07:00
Guenter Roeck
7b88344631 i8k: Add support for Dell Precision 490 and Latitude D520
Both systems need non-standard parameters for fan multiplier
and maximum fan speed.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: Andreas Mohr <andi@lisas.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-09 16:41:36 -07:00