Commit Graph

648628 Commits

Author SHA1 Message Date
Johan Hovold 39712e8bfa USB: serial: ti_usb_3410_5052: fix control-message error handling
Make sure to detect and return an error on zero-length control-message
transfers when reading from the device.

This addresses a potential failure to detect an empty transmit buffer
during close.

Also remove a redundant check for short transfer when sending a command.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:57 +01:00
Johan Hovold 1eac5c244f USB: serial: ssu100: fix control-message error handling
Make sure to detect short control-message transfers rather than continue
with zero-initialised data when retrieving modem status and during
device initialisation.

Fixes: 52af954599 ("USB: add USB serial ssu100 driver")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:57 +01:00
Johan Hovold 5ed8d41023 USB: serial: spcp8x5: fix modem-status handling
Make sure to detect short control transfers and return zero on success
when retrieving the modem status.

This fixes the TIOCMGET implementation which since e1ed212d85 ("USB:
spcp8x5: add proper modem-status support") has returned TIOCM_LE on
successful retrieval, and avoids leaking bits from the stack on short
transfers.

This also fixes the carrier-detect implementation which since the above
mentioned commit unconditionally has returned true.

Fixes: e1ed212d85 ("USB: spcp8x5: add proper modem-status support")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:56 +01:00
Johan Hovold 8c34cb8ddf USB: serial: quatech2: fix control-message error handling
Make sure to detect short control-message transfers when fetching
modem and line state in open and when retrieving registers.

This specifically makes sure that an errno is returned to user space on
errors in TIOCMGET instead of a zero bitmask.

Also drop the unused getdevice function which also lacked appropriate
error handling.

Fixes: f7a33e608d ("USB: serial: add quatech2 usb to serial driver")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:56 +01:00
Johan Hovold b5fda434b1 USB: serial: pl2303: fix line-setting error handling
Make sure to return an error on zero-length transfers when retrieving
the line settings even if the driver currently ignores the return value.

Also remove a redundant check for short transfer when setting the line
settings.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:56 +01:00
Johan Hovold cd8db057e9 USB: serial: mos7840: fix control-message error handling
Make sure to detect short transfers when reading a device register.

The modem-status handling had sufficient error checks in place, but move
handling of short transfers into the register accessor function itself
for consistency.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:56 +01:00
Johan Hovold 0d130367ab USB: serial: mos7720: fix control-message error handling
Make sure to log an error on short transfers when reading a device
register.

Also clear the provided buffer (which if often an uninitialised
automatic variable) on errors as the driver currently does not bother to
check for errors.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:56 +01:00
Johan Hovold 36356a669e USB: serial: mct_u232: fix modem-status error handling
Make sure to detect short control-message transfers so that errors are
logged when reading the modem status at open.

Note that while this also avoids initialising the modem status using
uninitialised heap data, these bits could not leak to user space as they
are currently not used.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:56 +01:00
Johan Hovold 750acdd781 USB: serial: iuu_phoenix: remove unused buffer from open
Remove code that allocated but never used a buffer during open.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:56 +01:00
Johan Hovold 3c0e25d883 USB: serial: io_edgeport: fix descriptor error handling
Make sure to detect short control-message transfers and log an error
when reading incomplete manufacturer and boot descriptors.

Note that the default all-zero descriptors will now be used after a
short transfer is detected instead of partially initialised ones.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:56 +01:00
Johan Hovold e4457d9798 USB: serial: io_edgeport: fix epic-descriptor handling
Use a dedicated buffer for the DMA transfer and make sure to detect
short transfers to avoid parsing a corrupt descriptor.

Fixes: 6e8cf7751f ("USB: add EPIC support to the io_edgeport driver")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:56 +01:00
Johan Hovold e3e574ad85 USB: serial: ftdi_sio: fix latency-timer error handling
Make sure to detect short responses when reading the latency timer to
avoid using stale buffer data.

Note that no heap data would currently leak through sysfs as
ASYNC_LOW_LATENCY is set by default.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:55 +01:00
Johan Hovold 427c3a95e3 USB: serial: ftdi_sio: fix modem-status error handling
Make sure to detect short responses when fetching the modem status in
order to avoid parsing uninitialised buffer data and having bits of it
leak to user space.

Note that we still allow for short 1-byte responses.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:55 +01:00
Johan Hovold b631433b17 USB: serial: ark3116: fix open error handling
Fix open error handling which failed to detect errors when reading the
MSR and LSR registers, something which could lead to the shadow
registers being initialised from errnos.

Note that calling the generic close implementation is sufficient in the
error paths as the interrupt urb has not yet been submitted and the
register updates have not been made.

Fixes: f4c1e8d597 ("USB: ark3116: Make existing functions 16450-aware
and add close and release functions.")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:55 +01:00
Johan Hovold 9fef37d7cf USB: serial: ark3116: fix register-accessor error handling
The current implementation failed to detect short transfers, something
which could lead to bits of the uninitialised heap transfer buffer
leaking to user space.

Fixes: 149fc791a4 ("USB: ark3116: Setup some basic infrastructure for
new ark3116 driver.")
Fixes: f4c1e8d597 ("USB: ark3116: Make existing functions 16450-aware
and add close and release functions.")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 16:38:55 +01:00
Johan Hovold 2c85e0a961 USB: serial: kl5kusb105: remove unused termios structure
Remove unused termios structure from private data that was left by an
earlier purge by commit b1cff285ae ("usb serial: Eliminate bogus ioctl
code").

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 13:00:22 +01:00
Johan Hovold c2a24bb1e4 USB: serial: kl5kusb105: clean up struct definition
Drop redundant packed attribute from the port-settings struct which is
already 1-byte aligned. Also replace __u8 with u8 for the field types as
this is not a structure we share with user space.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 13:00:15 +01:00
Johan Hovold 2d11f28207 USB: serial: kl5kusb105: remove dead code
Remove dead and broken code that only served as a reminder to one day
implement modem control.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 13:00:04 +01:00
Johan Hovold 0546579330 USB: serial: kl5kusb105: make logging less verbose
Replace a couple of dev_info with dev_dbg and remove another.

Also use the port device for logging, and include a radix prefix when
logging the baudrate.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 12:59:41 +01:00
Johan Hovold 7c61b0d5e8 USB: serial: ch341: change initial line-control settings
Some CH340 devices appear unable to change the initial LCR settings, so
set a sane 8N1 default during probe to enable basic support for such
devices.

Also drop a redundant LCR read during device initialisation.

Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 12:32:21 +01:00
Johan Hovold 448b6dc5a9 USB: serial: ch341: rename LCR variable in set_termios
Rename the line-control-register variable in set_termios to "lcr" and
use u8 type to match the shadow register.

Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 12:32:21 +01:00
Johan Hovold e802446035 USB: serial: ch341: rename modem-status register
Rename the shadow modem-status register currently named "line_status" to
the less confusing "msr".

Also rename the helper function used to parse the interrupt data.

Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 12:32:20 +01:00
Johan Hovold beea33d4f9 USB: serial: ch341: rename shadow modem-control register
Rename the shadow modem-control register currently named "line_control"
to the less confusing "mcr".

Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 12:32:20 +01:00
Johan Hovold 91e0efcd4c USB: serial: ch341: clean up control debug messages
Clean up the control-transfer debug messages by dropping redundant
information and unnecessary casts.

Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 12:31:56 +01:00
Johan Hovold a0467a967f USB: serial: ch341: fix modem-status handling
The modem-status register was read as part of device configuration at
port_probe and then again at open (and reset-resume). During open (and
reset-resume) the MSR was read before submitting the interrupt URB,
something which could lead to an MSR-change going unnoticed when it
races with open (reset-resume).

Fix this by dropping the redundant reconfiguration of the port at every
open, and only read the MSR after the interrupt URB has been submitted.

Fixes: 664d5df92e ("USB: usb-serial ch341: support for DTR/RTS/CTS")
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 12:30:45 +01:00
Sudip Mukherjee 56e6d90797 USB: serial: cypress_m8: remove unused variable
The variable havedata was only being set but never used afterwards.

Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-01-16 12:26:58 +01:00
Linus Torvalds 49def18533 Linux 4.10-rc4 2017-01-15 16:21:59 -08:00
Linus Torvalds 99421c1cb2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull namespace fixes from Eric Biederman:
 "This tree contains 4 fixes.

  The first is a fix for a race that can causes oopses under the right
  circumstances, and that someone just recently encountered.

  Past that are several small trivial correct fixes. A real issue that
  was blocking development of an out of tree driver, but does not appear
  to have caused any actual problems for in-tree code. A potential
  deadlock that was reported by lockdep. And a deadlock people have
  experienced and took the time to track down caused by a cleanup that
  removed the code to drop a reference count"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  sysctl: Drop reference added by grab_header in proc_sys_readdir
  pid: fix lockdep deadlock warning due to ucount_lock
  libfs: Modify mount_pseudo_xattr to be clear it is not a userspace mount
  mnt: Protect the mountpoint hashtable with mount_lock
2017-01-15 16:09:50 -08:00
Linus Torvalds c928162756 char/misc driver fixes for 4.10-rc4
Here are some small char/misc driver fixes for 4.10-rc4 that resolve
 some reported issues.  The MEI driver issue resolves a lot of problems
 that people have been having, as does the mem driver fix.  The other
 minor fixes resolve other reported issues.
 
 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 'char-misc-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver fixes from Greg KH:
 "Here are some small char/misc driver fixes for 4.10-rc4 that resolve
  some reported issues.

  The MEI driver issue resolves a lot of problems that people have been
  having, as does the mem driver fix. The other minor fixes resolve
  other reported issues.

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

* tag 'char-misc-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  vme: Fix wrong pointer utilization in ca91cx42_slave_get
  auxdisplay: fix new ht16k33 build errors
  ppdev: don't print a free'd string
  extcon: return error code on failure
  drivers: char: mem: Fix thinkos in kmem address checks
  mei: bus: enable OS version only for SPT and newer
2017-01-15 12:40:53 -08:00
Linus Torvalds 2d5a7101a1 Driver core fix for 4.10-rc4
Here is a single patch being reverted to remove a feature that was added
 in 4.10-rc1 that isn't quite ready for release.  It will be redone as a
 debugfs file instead of a sysfs file in the future.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fix from Greg KH:
 "Here is a single patch being reverted to remove a feature that was
  added in 4.10-rc1 that isn't quite ready for release.

  It will be redone as a debugfs file instead of a sysfs file in the
  future"

* tag 'driver-core-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  Revert "driver core: Add deferred_probe attribute to devices in sysfs"
2017-01-15 12:38:53 -08:00
Linus Torvalds 7f138b9706 TTY/serial fixes for 4.10-rc4
Here are some small tty/serial driver fixes for 4.10-rc4 to resolve a
 number of reported issues.
 
 Nothing major here at all, one revert of a problematic patch, and some
 other tiny bugfixes.  Full details are in the shortlog below.
 
 All have been in linux-next with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are some small tty/serial driver fixes for 4.10-rc4 to resolve a
  number of reported issues.

  Nothing major here at all, one revert of a problematic patch, and some
  other tiny bugfixes. Full details are in the shortlog below.

  All have been in linux-next with no reported issues"

* tag 'tty-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  sysrq: attach sysrq handler correctly for 32-bit kernel
  Revert "tty: serial: 8250: add CON_CONSDEV to flags"
  Clearing FIFOs in RS485 emulation mode causes subsequent transmits to break
  8250_pci: Fix potential use-after-free in error path
  tty/serial: atmel: RS485 half duplex w/DMA: enable RX after TX is done
  tty/serial: atmel_serial: BUG: stop DMA from transmitting in stop_tx
2017-01-15 12:36:32 -08:00
Linus Torvalds 793e039ea0 USB fixes for 4.10-rc4
Here are a few small USB driver fixes for 4.10-rc4 to resolve some
 reported issues.  The "largest" here is a number of bugs being fixed in
 the ch341 usb-serial driver, to hopefully resolve the mess of different
 devices floating around that use this driver that have been having
 problems with the 4.10-rc1 release.  There's also a tiny musb fix that I
 missed in the last pull request, as well as the traditional xhci fix
 rounding out the batch.
 
 All have been in linux-next with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
 "Here are a few small USB driver fixes for 4.10-rc4 to resolve some
  reported issues.

  The "largest" here is a number of bugs being fixed in the ch341
  usb-serial driver, to hopefully resolve the mess of different devices
  floating around that use this driver that have been having problems
  with the 4.10-rc1 release.

  There's also a tiny musb fix that I missed in the last pull request,
  as well as the traditional xhci fix rounding out the batch.

  All have been in linux-next with no reported issues"

* tag 'usb-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  xhci: fix deadlock at host remove by running watchdog correctly
  USB: serial: ch341: fix control-message error handling
  usb: musb: fix runtime PM in debugfs
  wusbcore: Fix one more crypto-on-the-stack bug
  USB: serial: kl5kusb105: fix line-state error handling
  USB: serial: ch341: fix baud rate and line-control handling
  USB: serial: ch341: fix line settings after reset-resume
  USB: serial: ch341: fix resume after reset
  USB: serial: ch341: fix open error handling
  USB: serial: ch341: fix modem-control and B0 handling
  USB: serial: ch341: fix open and resume after B0
  USB: serial: ch341: fix initial modem-control state
2017-01-15 12:34:35 -08:00
Linus Torvalds aa2797b30c Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c fixes from Wolfram Sang:
 "Bugfixes for I2C. Mostly core this time which is a bit unusual but
  nothing really scary in there"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: piix4: Avoid race conditions with IMC
  i2c: fix spelling mistake: "insufficent" -> "insufficient"
  i2c: print correct device invalid address
  i2c: do not enable fall back to Host Notify by default
  i2c: fix kernel memory disclosure in dev interface
2017-01-15 12:28:14 -08:00
Linus Torvalds 83346fbc07 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes:

   - unwinder fixes
   - AMD CPU topology enumeration fixes
   - microcode loader fixes
   - x86 embedded platform fixes
   - fix for a bootup crash that may trigger when clearcpuid= is used
     with invalid values"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mpx: Use compatible types in comparison to fix sparse error
  x86/tsc: Add the Intel Denverton Processor to native_calibrate_tsc()
  x86/entry: Fix the end of the stack for newly forked tasks
  x86/unwind: Include __schedule() in stack traces
  x86/unwind: Disable KASAN checks for non-current tasks
  x86/unwind: Silence warnings for non-current tasks
  x86/microcode/intel: Use correct buffer size for saving microcode data
  x86/microcode/intel: Fix allocation size of struct ucode_patch
  x86/microcode/intel: Add a helper which gives the microcode revision
  x86/microcode: Use native CPUID to tickle out microcode revision
  x86/CPU: Add native CPUID variants returning a single datum
  x86/boot: Add missing declaration of string functions
  x86/CPU/AMD: Fix Bulldozer topology
  x86/platform/intel-mid: Rename 'spidev' to 'mrfld_spidev'
  x86/cpu: Fix typo in the comment for Anniedale
  x86/cpu: Fix bootup crashes by sanitizing the argument of the 'clearcpuid=' command-line option
2017-01-15 12:03:11 -08:00
Linus Torvalds a11ce3a4ac Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull NOHZ fix from Ingo Molnar:
 "This fixes an old NOHZ race where we incorrectly calculate the next
  timer interrupt in certain circumstances where hrtimers are pending,
  that can cause hard to reproduce stalled-values artifacts in
  /proc/stat"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  nohz: Fix collision between tick and other hrtimers
2017-01-15 12:00:37 -08:00
Linus Torvalds 79078c53ba Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Misc race fixes uncovered by fuzzing efforts, a Sparse fix, two PMU
  driver fixes, plus miscellanous tooling fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86: Reject non sampling events with precise_ip
  perf/x86/intel: Account interrupts for PEBS errors
  perf/core: Fix concurrent sys_perf_event_open() vs. 'move_group' race
  perf/core: Fix sys_perf_event_open() vs. hotplug
  perf/x86/intel: Use ULL constant to prevent undefined shift behaviour
  perf/x86/intel/uncore: Fix hardcoded socket 0 assumption in the Haswell init code
  perf/x86: Set pmu->module in Intel PMU modules
  perf probe: Fix to probe on gcc generated symbols for offline kernel
  perf probe: Fix --funcs to show correct symbols for offline module
  perf symbols: Robustify reading of build-id from sysfs
  perf tools: Install tools/lib/traceevent plugins with install-bin
  tools lib traceevent: Fix prev/next_prio for deadline tasks
  perf record: Fix --switch-output documentation and comment
  perf record: Make __record_options static
  tools lib subcmd: Add OPT_STRING_OPTARG_SET option
  perf probe: Fix to get correct modname from elf header
  samples/bpf trace_output_user: Remove duplicate sys/ioctl.h include
  samples/bpf sock_example: Avoid getting ethhdr from two includes
  perf sched timehist: Show total scheduling time
2017-01-15 11:37:43 -08:00
Linus Torvalds 255e6140fa Merge branch 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI fixes from Ingo Molnar:
 "A number of regression fixes:

   - Fix a boot hang on machines that have somewhat unusual memory map
     entries of phys_addr=0x0 num_pages=0, which broke due to a recent
     commit. This commit got cherry-picked from the v4.11 queue because
     the bug is affecting real machines.

   - Fix a boot hang also reported by KASAN, caused by incorrect init
     ordering introduced by a recent optimization.

   - Fix a recent robustification fix to allocate_new_fdt_and_exit_boot()
     that introduced an invalid assumption. Neither bugs were seen in
     the wild AFAIK"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/x86: Prune invalid memory map entries and fix boot regression
  x86/efi: Don't allocate memmap through memblock after mm_init()
  efi/libstub/arm*: Pass latest memory map to the kernel
2017-01-15 10:54:39 -08:00
Linus Torvalds f4d3935e4f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro.

The most notable fix here is probably the fix for a splice regression
("fix a fencepost error in pipe_advance()") noticed by Alan Wylie.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fix a fencepost error in pipe_advance()
  coredump: Ensure proper size of sparse core files
  aio: fix lock dep warning
  tmpfs: clear S_ISGID when setting posix ACLs
2017-01-14 17:13:28 -08:00
Linus Torvalds 34241af77b Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:

 - the virtio_blk stack DMA corruption fix from Christoph, fixing and
   issue with VMAP stacks.

 - O_DIRECT blkbits calculation fix from Chandan.

 - discard regression fix from Christoph.

 - queue init error handling fixes for nbd and virtio_blk, from Omar and
   Jeff.

 - two small nvme fixes, from Christoph and Guilherme.

 - rename of blk_queue_zone_size and bdev_zone_size to _sectors instead,
   to more closely follow what we do in other places in the block layer.
   This interface is new for this series, so let's get the naming right
   before releasing a kernel with this feature. From Damien.

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: don't try to discard from __blkdev_issue_zeroout
  sd: remove __data_len hack for WRITE SAME
  nvme: use blk_rq_payload_bytes
  scsi: use blk_rq_payload_bytes
  block: add blk_rq_payload_bytes
  block: Rename blk_queue_zone_size and bdev_zone_size
  nvme: apply DELAY_BEFORE_CHK_RDY quirk at probe time too
  nvme-rdma: fix nvme_rdma_queue_is_ready
  virtio_blk: fix panic in initialization error path
  nbd: blk_mq_init_queue returns an error code on failure, not NULL
  virtio_blk: avoid DMA to stack for the sense buffer
  do_direct_IO: Use inode->i_blkbits to compute block count to be cleaned
2017-01-14 17:07:04 -08:00
Al Viro b9dc6f65bc fix a fencepost error in pipe_advance()
The logics in pipe_advance() used to release all buffers past the new
position failed in cases when the number of buffers to release was equal
to pipe->buffers.  If that happened, none of them had been released,
leaving pipe full.  Worse, it was trivial to trigger and we end up with
pipe full of uninitialized pages.  IOW, it's an infoleak.

Cc: stable@vger.kernel.org # v4.9
Reported-by: "Alan J. Wylie" <alan@wylie.me.uk>
Tested-by: "Alan J. Wylie" <alan@wylie.me.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-01-14 19:50:41 -05:00
Dave Kleikamp 4d22c75d4c coredump: Ensure proper size of sparse core files
If the last section of a core file ends with an unmapped or zero page,
the size of the file does not correspond with the last dump_skip() call.
gdb complains that the file is truncated and can be confusing to users.

After all of the vma sections are written, make sure that the file size
is no smaller than the current file position.

This problem can be demonstrated with gdb's bigcore testcase on the
sparc architecture.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-01-14 19:32:40 -05:00
Shaohua Li a12f1ae61c aio: fix lock dep warning
lockdep reports a warnning. file_start_write/file_end_write only
acquire/release the lock for regular files. So checking the files in aio
side too.

[  453.532141] ------------[ cut here ]------------
[  453.533011] WARNING: CPU: 1 PID: 1298 at ../kernel/locking/lockdep.c:3514 lock_release+0x434/0x670
[  453.533011] DEBUG_LOCKS_WARN_ON(depth <= 0)
[  453.533011] Modules linked in:
[  453.533011] CPU: 1 PID: 1298 Comm: fio Not tainted 4.9.0+ #964
[  453.533011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.0-1.fc24 04/01/2014
[  453.533011]  ffff8803a24b7a70 ffffffff8196cffb ffff8803a24b7ae8 0000000000000000
[  453.533011]  ffff8803a24b7ab8 ffffffff81091ee1 ffff8803a5dba700 00000dba00000008
[  453.533011]  ffffed0074496f59 ffff8803a5dbaf54 ffff8803ae0f8488 fffffffffffffdef
[  453.533011] Call Trace:
[  453.533011]  [<ffffffff8196cffb>] dump_stack+0x67/0x9c
[  453.533011]  [<ffffffff81091ee1>] __warn+0x111/0x130
[  453.533011]  [<ffffffff81091f97>] warn_slowpath_fmt+0x97/0xb0
[  453.533011]  [<ffffffff81091f00>] ? __warn+0x130/0x130
[  453.533011]  [<ffffffff8191b789>] ? blk_finish_plug+0x29/0x60
[  453.533011]  [<ffffffff811205d4>] lock_release+0x434/0x670
[  453.533011]  [<ffffffff8198af94>] ? import_single_range+0xd4/0x110
[  453.533011]  [<ffffffff81322195>] ? rw_verify_area+0x65/0x140
[  453.533011]  [<ffffffff813aa696>] ? aio_write+0x1f6/0x280
[  453.533011]  [<ffffffff813aa6c9>] aio_write+0x229/0x280
[  453.533011]  [<ffffffff813aa4a0>] ? aio_complete+0x640/0x640
[  453.533011]  [<ffffffff8111df20>] ? debug_check_no_locks_freed+0x1a0/0x1a0
[  453.533011]  [<ffffffff8114793a>] ? debug_lockdep_rcu_enabled.part.2+0x1a/0x30
[  453.533011]  [<ffffffff81147985>] ? debug_lockdep_rcu_enabled+0x35/0x40
[  453.533011]  [<ffffffff812a92be>] ? __might_fault+0x7e/0xf0
[  453.533011]  [<ffffffff813ac9bc>] do_io_submit+0x94c/0xb10
[  453.533011]  [<ffffffff813ac2ae>] ? do_io_submit+0x23e/0xb10
[  453.533011]  [<ffffffff813ac070>] ? SyS_io_destroy+0x270/0x270
[  453.533011]  [<ffffffff8111d7b3>] ? mark_held_locks+0x23/0xc0
[  453.533011]  [<ffffffff8100201a>] ? trace_hardirqs_on_thunk+0x1a/0x1c
[  453.533011]  [<ffffffff813acb90>] SyS_io_submit+0x10/0x20
[  453.533011]  [<ffffffff824f96aa>] entry_SYSCALL_64_fastpath+0x18/0xad
[  453.533011]  [<ffffffff81119190>] ? trace_hardirqs_off_caller+0xc0/0x110
[  453.533011] ---[ end trace b2fbe664d1cc0082 ]---

Cc: Dmitry Monakhov <dmonakhov@openvz.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-01-14 19:31:40 -05:00
Linus Torvalds f0ad17712b dmaengine-4.10-rc4
dmaengine fixes for 4.10-rc4
 
 The fixes this time around are spread over drivers, pretty normal update.
 
  o PCI ID for SKL ioatdma, workaround for SKX and ioat_alloc_chan_resources
    sleepy allocation fix.
  o dw kconfig typo fix
  o null pointer deref for stm32
  o MAINTAINERS Update for at_hdmac
  o pl330 runtime pm fixes
  o omap-dma port window fix
  o rcar-dmac unmap slave resource fix.
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Merge tag 'dmaengine-fix-4.10-rc4' of git://git.infradead.org/users/vkoul/slave-dma

Pull dmaengine fixes from Vinod Koul:
 "The fixes this time around are spread over drivers, pretty normal
  update:

   - PCI ID for SKL ioatdma, workaround for SKX and
     ioat_alloc_chan_resources sleepy allocation fix

   - dw kconfig typo fix

   - null pointer deref for stm32

   - MAINTAINERS Update for at_hdmac

   - pl330 runtime pm fixes

   - omap-dma port window fix

   - rcar-dmac unmap slave resource fix"

* tag 'dmaengine-fix-4.10-rc4' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: rcar-dmac: unmap slave resource when channel is freed
  dmaengine: omap-dma: Fix the port_window support
  dmaengine: iota: ioat_alloc_chan_resources should not perform sleeping allocations.
  dmaengine: pl330: Fix runtime PM support for terminated transfers
  MAINTAINERS: dmaengine: Update + Hand over the at_hdmac driver to Ludovic
  dmaengine: omap-dma: Fix dynamic lch_map allocation
  dmaengine: ti-dma-crossbar: Add some 'of_node_put()' in error path.
  dmaengine: stm32-dma: Fix null pointer dereference in stm32_dma_tx_status
  dmaengine: stm32-dma: Set correct args number for DMA request from DT
  dmaengine: dw: fix typo in Kconfig
  dmaengine: ioatdma: workaround SKX ioatdma version
  dmaengine: ioatdma: Add Skylake PCI Dev ID
2017-01-14 11:09:24 -08:00
Peter Jones 0100a3e67a efi/x86: Prune invalid memory map entries and fix boot regression
Some machines, such as the Lenovo ThinkPad W541 with firmware GNET80WW
(2.28), include memory map entries with phys_addr=0x0 and num_pages=0.

These machines fail to boot after the following commit,

  commit 8e80632fb2 ("efi/esrt: Use efi_mem_reserve() and avoid a kmalloc()")

Fix this by removing such bogus entries from the memory map.

Furthermore, currently the log output for this case (with efi=debug)
looks like:

 [    0.000000] efi: mem45: [Reserved           |   |  |  |  |  |  |  |  |  |  |  |  ] range=[0x0000000000000000-0xffffffffffffffff] (0MB)

This is clearly wrong, and also not as informative as it could be.  This
patch changes it so that if we find obviously invalid memory map
entries, we print an error and skip those entries.  It also detects the
display of the address range calculation overflow, so the new output is:

 [    0.000000] efi: [Firmware Bug]: Invalid EFI memory map entries:
 [    0.000000] efi: mem45: [Reserved           |   |  |  |  |  |  |  |   |  |  |  |  ] range=[0x0000000000000000-0x0000000000000000] (invalid)

It also detects memory map sizes that would overflow the physical
address, for example phys_addr=0xfffffffffffff000 and
num_pages=0x0200000000000001, and prints:

 [    0.000000] efi: [Firmware Bug]: Invalid EFI memory map entries:
 [    0.000000] efi: mem45: [Reserved           |   |  |  |  |  |  |  |   |  |  |  |  ] range=[phys_addr=0xfffffffffffff000-0x20ffffffffffffffff] (invalid)

It then removes these entries from the memory map.

Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[ardb: refactor for clarity with no functional changes, avoid PAGE_SHIFT]
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
[Matt: Include bugzilla info in commit log]
Cc: <stable@vger.kernel.org> # v4.9+
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=191121
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 16:48:53 +01:00
Greg Kroah-Hartman c7334ce814 Revert "driver core: Add deferred_probe attribute to devices in sysfs"
This reverts commit 6751667a29.

Rob Herring objected to it, and a replacement for it will be added using
debugfs in the future.

Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
Reported-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-14 14:09:03 +01:00
Jiri Olsa 18e7a45af9 perf/x86: Reject non sampling events with precise_ip
As Peter suggested [1] rejecting non sampling PEBS events,
because they dont make any sense and could cause bugs
in the NMI handler [2].

  [1] http://lkml.kernel.org/r/20170103094059.GC3093@worktop
  [2] http://lkml.kernel.org/r/1482931866-6018-3-git-send-email-jolsa@kernel.org

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vince@deater.net>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/20170103142454.GA26251@krava
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:06:50 +01:00
Jiri Olsa 475113d937 perf/x86/intel: Account interrupts for PEBS errors
It's possible to set up PEBS events to get only errors and not
any data, like on SNB-X (model 45) and IVB-EP (model 62)
via 2 perf commands running simultaneously:

    taskset -c 1 ./perf record -c 4 -e branches:pp -j any -C 10

This leads to a soft lock up, because the error path of the
intel_pmu_drain_pebs_nhm() does not account event->hw.interrupt
for error PEBS interrupts, so in case you're getting ONLY
errors you don't have a way to stop the event when it's over
the max_samples_per_tick limit:

  NMI watchdog: BUG: soft lockup - CPU#22 stuck for 22s! [perf_fuzzer:5816]
  ...
  RIP: 0010:[<ffffffff81159232>]  [<ffffffff81159232>] smp_call_function_single+0xe2/0x140
  ...
  Call Trace:
   ? trace_hardirqs_on_caller+0xf5/0x1b0
   ? perf_cgroup_attach+0x70/0x70
   perf_install_in_context+0x199/0x1b0
   ? ctx_resched+0x90/0x90
   SYSC_perf_event_open+0x641/0xf90
   SyS_perf_event_open+0x9/0x10
   do_syscall_64+0x6c/0x1f0
   entry_SYSCALL64_slow_path+0x25/0x25

Add perf_event_account_interrupt() which does the interrupt
and frequency checks and call it from intel_pmu_drain_pebs_nhm()'s
error path.

We keep the pending_kill and pending_wakeup logic only in the
__perf_event_overflow() path, because they make sense only if
there's any data to deliver.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vince@deater.net>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1482931866-6018-2-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:06:49 +01:00
Peter Zijlstra 321027c1fe perf/core: Fix concurrent sys_perf_event_open() vs. 'move_group' race
Di Shen reported a race between two concurrent sys_perf_event_open()
calls where both try and move the same pre-existing software group
into a hardware context.

The problem is exactly that described in commit:

  f63a8daa58 ("perf: Fix event->ctx locking")

... where, while we wait for a ctx->mutex acquisition, the event->ctx
relation can have changed under us.

That very same commit failed to recognise sys_perf_event_context() as an
external access vector to the events and thereby didn't apply the
established locking rules correctly.

So while one sys_perf_event_open() call is stuck waiting on
mutex_lock_double(), the other (which owns said locks) moves the group
about. So by the time the former sys_perf_event_open() acquires the
locks, the context we've acquired is stale (and possibly dead).

Apply the established locking rules as per perf_event_ctx_lock_nested()
to the mutex_lock_double() for the 'move_group' case. This obviously means
we need to validate state after we acquire the locks.

Reported-by: Di Shen (Keen Lab)
Tested-by: John Dias <joaodias@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Min Chong <mchong@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: f63a8daa58 ("perf: Fix event->ctx locking")
Link: http://lkml.kernel.org/r/20170106131444.GZ3174@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 10:56:11 +01:00
Peter Zijlstra 63cae12bce perf/core: Fix sys_perf_event_open() vs. hotplug
There is problem with installing an event in a task that is 'stuck' on
an offline CPU.

Blocked tasks are not dis-assosciated from offlined CPUs, after all, a
blocked task doesn't run and doesn't require a CPU etc.. Only on
wakeup do we ammend the situation and place the task on a available
CPU.

If we hit such a task with perf_install_in_context() we'll loop until
either that task wakes up or the CPU comes back online, if the task
waking depends on the event being installed, we're stuck.

While looking into this issue, I also spotted another problem, if we
hit a task with perf_install_in_context() that is in the middle of
being migrated, that is we observe the old CPU before sending the IPI,
but run the IPI (on the old CPU) while the task is already running on
the new CPU, things also go sideways.

Rework things to rely on task_curr() -- outside of rq->lock -- which
is rather tricky. Imagine the following scenario where we're trying to
install the first event into our task 't':

CPU0            CPU1            CPU2

                (current == t)

t->perf_event_ctxp[] = ctx;
smp_mb();
cpu = task_cpu(t);

                switch(t, n);
                                migrate(t, 2);
                                switch(p, t);

                                ctx = t->perf_event_ctxp[]; // must not be NULL

smp_function_call(cpu, ..);

                generic_exec_single()
                  func();
                    spin_lock(ctx->lock);
                    if (task_curr(t)) // false

                    add_event_to_ctx();
                    spin_unlock(ctx->lock);

                                perf_event_context_sched_in();
                                  spin_lock(ctx->lock);
                                  // sees event

So its CPU0's store of t->perf_event_ctxp[] that must not go 'missing'.
Because if CPU2's load of that variable were to observe NULL, it would
not try to schedule the ctx and we'd have a task running without its
counter, which would be 'bad'.

As long as we observe !NULL, we'll acquire ctx->lock. If we acquire it
first and not see the event yet, then CPU0 must observe task_curr()
and retry. If the install happens first, then we must see the event on
sched-in and all is well.

I think we can translate the first part (until the 'must not be NULL')
of the scenario to a litmus test like:

  C C-peterz

  {
  }

  P0(int *x, int *y)
  {
          int r1;

          WRITE_ONCE(*x, 1);
          smp_mb();
          r1 = READ_ONCE(*y);
  }

  P1(int *y, int *z)
  {
          WRITE_ONCE(*y, 1);
          smp_store_release(z, 1);
  }

  P2(int *x, int *z)
  {
          int r1;
          int r2;

          r1 = smp_load_acquire(z);
	  smp_mb();
          r2 = READ_ONCE(*x);
  }

  exists
  (0:r1=0 /\ 2:r1=1 /\ 2:r2=0)

Where:
  x is perf_event_ctxp[],
  y is our tasks's CPU, and
  z is our task being placed on the rq of CPU2.

The P0 smp_mb() is the one added by this patch, ordering the store to
perf_event_ctxp[] from find_get_context() and the load of task_cpu()
in task_function_call().

The smp_store_release/smp_load_acquire model the RCpc locking of the
rq->lock and the smp_mb() of P2 is the context switch switching from
whatever CPU2 was running to our task 't'.

This litmus test evaluates into:

  Test C-peterz Allowed
  States 7
  0:r1=0; 2:r1=0; 2:r2=0;
  0:r1=0; 2:r1=0; 2:r2=1;
  0:r1=0; 2:r1=1; 2:r2=1;
  0:r1=1; 2:r1=0; 2:r2=0;
  0:r1=1; 2:r1=0; 2:r2=1;
  0:r1=1; 2:r1=1; 2:r2=0;
  0:r1=1; 2:r1=1; 2:r2=1;
  No
  Witnesses
  Positive: 0 Negative: 7
  Condition exists (0:r1=0 /\ 2:r1=1 /\ 2:r2=0)
  Observation C-peterz Never 0 7
  Hash=e427f41d9146b2a5445101d3e2fcaa34

And the strong and weak model agree.

Reported-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Will Deacon <will.deacon@arm.com>
Cc: jeremy.linton@arm.com
Link: http://lkml.kernel.org/r/20161209135900.GU3174@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 10:56:10 +01:00
Tobias Klauser 4538286257 x86/mpx: Use compatible types in comparison to fix sparse error
info->si_addr is of type void __user *, so it should be compared against
something from the same address space.

This fixes the following sparse error:

  arch/x86/mm/mpx.c:296:27: error: incompatible types in comparison expression (different address spaces)

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 09:32:06 +01:00