fs/proc/task_mmu.c: fix buffer overflow in add_page_map()

commit 8c8296223f3abb142be8fc31711b18a704c0e7d8 upstream.

Recently we met quite a lot of random kernel panic issues after enabling
CONFIG_PROC_PAGE_MONITOR.  After debuggind we found this has something
to do with following bug in pagemap:

In struct pagemapread:

  struct pagemapread {
      int pos, len;
      pagemap_entry_t *buffer;
      bool v2;
  };

pos is number of PM_ENTRY_BYTES in buffer, but len is the size of
buffer, it is a mistake to compare pos and len in add_page_map() for
checking buffer is full or not, and this can lead to buffer overflow and
random kernel panic issue.

Correct len to be total number of PM_ENTRY_BYTES in buffer.

[akpm@linux-foundation.org: document pagemapread.pos and .len units, fix PM_ENTRY_BYTES definition]
Signed-off-by: Yonghua Zheng <younghua.zheng@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/i915/lvds: ditch ->prepare special case

commit 520c41cf2fa029d1e8b923ac2026f96664f17c4b upstream.

LVDS is the first output where dpms on/off and prepare/commit don't
perfectly match. Now the idea behind this special case seems to be
that for simple resolution changes on the LVDS we don't need to stop
the pipe, because (at least on newer chips) we can adjust the panel
fitter on the fly.

There are a few problems with the current code though:
- We still stop and restart the pipe unconditionally, because the crtc
  helper code isn't flexible enough.
- We show some ugly flickering, especially when changing crtcs (this
  the crtc helper would actually take into account, but we don't
  implement the encoder->get_crtc callback required to make this work
  properly).

So it doesn't even work as advertised. I agree that it would be nice
to do resolution changes on LVDS (and also eDP) whithout blacking the
screen where the panel fitter allows to do that. But imo we should
implement this as a special case a few layers up in the mode set code,
akin to how we already detect simple framebuffer changes (and only
update the required registers with ->mode_set_base).

Until this is all in place, make our lives easier and just rip it out.

Also note that this seems to fix actual bugs with enabling the lvds
output, see:

http://lists.freedesktop.org/archives/intel-gfx/2012-July/018614.html

Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Giacomo Comes <comes@naic.edu>
Tested-by: Takashi Iwai <tiwai@suse.de>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Haitao Zhang <haitao.zhang@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
MIPS: Expose missing pci_io{map,unmap} declarations

commit 78857614104a26cdada4c53eea104752042bf5a1 upstream.

The GENERIC_PCI_IOMAP does not depend on CONFIG_PCI so move
it to the CONFIG_MIPS symbol so it's always selected for MIPS.
This fixes the missing pci_iomap declaration for MIPS.
Moreover, the pci_iounmap function was not defined in the
io.h header file if the CONFIG_PCI symbol is not set,
but it should since MIPS is not using CONFIG_GENERIC_IOMAP.

This fixes the following problem on a allyesconfig:

drivers/net/ethernet/3com/3c59x.c:1031:2: error: implicit declaration of
function 'pci_iomap' [-Werror=implicit-function-declaration]
drivers/net/ethernet/3com/3c59x.c:1044:3: error: implicit declaration of
function 'pci_iounmap' [-Werror=implicit-function-declaration]

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Acked-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5478/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
microblaze: Update microblaze defconfigs

commit d0e045401f268a8de6f87d65678214748b772680 upstream.

The main reason is 0-day testing system which can directly
use these defconfigs for testing.

Enable support for all xilinx drivers which Microblaze
can use and disable dependency on external rootfs.cpio.
There is only one exception which is axi ethernet driver
which still uses NO_IRQ which is not defined for Microblaze.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sound: Fix make allmodconfig on MIPS

commit d4702b189c6b951c1cb3260036ff998f719bfb62 upstream.

The compile of soundcard.c is broken on MIPS when allmodconfig is used
because of the missing MAX_DMA_CHANNELS definition.  As a simple
workaround, just add a Kconfig dependency.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sound: Fix make allmodconfig on MIPS correctly

commit a62ee234a572b4c98fe98cf5fb18e4e8b0f6e43d upstream.

Commit d4702b189c ("sound: Fix make allmodconfig on MIPS") added a
(negative) dependency on ISA_DMA_SUPPORT_BROKEN. Since that Kconfig
symbol doesn't exist, this dependency will always evaluate to true.
Apparently GENERIC_ISA_DMA_SUPPORT_BROKEN was meant to be used here.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
HID: microsoft: do not use compound literal - fix build

commit 6b90466cfec2a2fe027187d675d8d14217c12d82 upstream.

In patch "HID: microsoft: fix invalid rdesc for 3k kbd" I fixed
support for MS 3k keyboards. However the added check using memcmp and
a compound statement breaks build on architectures where memcmp is a
macro with parameters.

hid-microsoft.c:51:18: error: macro "memcmp" passed 6 arguments, but takes just 3

On x86_64, memcmp is a function, so I did not see the error.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vm: add no-mmu vm_iomap_memory() stub

commit 3c0b9de6d37a481673e81001c57ca0e410c72346 upstream.

I think we could just move the full vm_iomap_memory() function into
util.h or similar, but I didn't get any reply from anybody actually
using nommu even to this trivial patch, so I'm not going to touch it any
more than required.

Here's the fairly minimal stub to make the nommu case at least
potentially work.  It doesn't seem like anybody cares, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cris: posix_types.h, include asm-generic/posix_types.h

commit 74f077d2a7651409c44bb323471f219a4b0d2aab upstream.

Without that I cannot build anything:
In file included from include/linux/page-flags.h:8:0,
                 from kernel/bounds.c:9:
include/linux/types.h:25:1: error: unknown type name '__kernel_ino_t'
include/linux/types.h:29:1: error: unknown type name '__kernel_off_t'
...

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Mikael Starvik <starvik@axis.com>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: linux-cris-kernel@axis.com
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cris: Remove old legacy "-traditional" flag from arch-v10/lib/Makefile

commit 7b91747d42a1012e3781dd09fa638d113809e3fd upstream.

Most of these have been purged years ago.  This one silently lived
on until commit 69349c2dc01c489eccaa4c472542c08e370c6d7e

    "kconfig: fix IS_ENABLED to not require all options to be defined"

In the above, we use some macro trickery to create a conditional that
is valid in CPP and in C usage.  However that trickery doesn't sit
well if you have the legacy "-traditional" flag enabled.  You'll get:

  AS      arch/cris/arch-v10/lib/checksum.o
In file included from <command-line>:4:0:
include/linux/kconfig.h:23:0: error: syntax error in macro parameter list
make[2]: *** [arch/cris/arch-v10/lib/checksum.o] Error 1

Everything builds fine w/o "-traditional" so simply drop it from this
location as well.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CRIS: Add _sdata to vmlinux.lds.S

commit 473e162eea465e60578edb93341752e7f1c1dacc upstream.

Fixes link error:
  LD      vmlinux
kernel/built-in.o: In function `core_kernel_data':
(.text+0x13e44): undefined reference to `_sdata'

Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
futex: Take hugepages into account when generating futex_key

commit 13d60f4b6ab5b702dc8d2ee20999f98a93728aec upstream.

The futex_keys of process shared futexes are generated from the page
offset, the mapping host and the mapping index of the futex user space
address. This should result in an unique identifier for each futex.

Though this is not true when futexes are located in different subpages
of an hugepage. The reason is, that the mapping index for all those
futexes evaluates to the index of the base page of the hugetlbfs
mapping. So a futex at offset 0 of the hugepage mapping and another
one at offset PAGE_SIZE of the same hugepage mapping have identical
futex_keys. This happens because the futex code blindly uses
page->index.

Steps to reproduce the bug:

1. Map a file from hugetlbfs. Initialize pthread_mutex1 at offset 0
   and pthread_mutex2 at offset PAGE_SIZE of the hugetlbfs
   mapping.

   The mutexes must be initialized as PTHREAD_PROCESS_SHARED because
   PTHREAD_PROCESS_PRIVATE mutexes are not affected by this issue as
   their keys solely depend on the user space address.

2. Lock mutex1 and mutex2

3. Create thread1 and in the thread function lock mutex1, which
   results in thread1 blocking on the locked mutex1.

4. Create thread2 and in the thread function lock mutex2, which
   results in thread2 blocking on the locked mutex2.

5. Unlock mutex2. Despite the fact that mutex2 got unlocked, thread2
   still blocks on mutex2 because the futex_key points to mutex1.

To solve this issue we need to take the normal page index of the page
which contains the futex into account, if the futex is in an hugetlbfs
mapping. In other words, we calculate the normal page mapping index of
the subpage in the hugetlbfs mapping.

Mappings which are not based on hugetlbfs are not affected and still
use page->index.

Thanks to Mel Gorman who provided a patch for adding proper evaluation
functions to the hugetlbfs code to avoid exposing hugetlbfs specific
details to the futex code.

[ tglx: Massaged changelog ]

Signed-off-by: Zhang Yi <zhang.yi20@zte.com.cn>
Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn>
Tested-by: Ma Chenggong <ma.chenggong@zte.com.cn>
Reviewed-by: 'Mel Gorman' <mgorman@suse.de>
Acked-by: 'Darren Hart' <dvhart@linux.intel.com>
Cc: 'Peter Zijlstra' <peterz@infradead.org>
Link: http://lkml.kernel.org/r/000101ce71a6%24a83c5880%24f8b50980%24@com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Mike Galbraith <mgalbraith@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:

	kernel/futex.c
frv: Use correct size for task_struct allocation

commit cce4517f33384c3794c759e206cc8e1bb6df146b upstream.

alloc_task_struct_node() allocates THREAD_SIZE and maintains some
weird refcount in the allocated memory. This never blew up as
task_struct size on 32bit machines was always less than THREAD_SIZE

Allocate just sizeof(struct task_struct) and get rid of the magic
refcounting.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Howells <dhowells@redhat.com>
Link: http://lkml.kernel.org/r/20120503085033.898475542@linutronix.de
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frv: Use core allocator for task_struct

commit c6ae063aaf3786b9db7f19a90bf4ed8aaebb7f90 upstream.

There is no point having a copy of the core allocator.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Howells <dhowells@redhat.com>
Link: http://lkml.kernel.org/r/20120503085033.967140188@linutronix.de
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc/numa: Avoid stupid uninitialized warning from gcc

commit aa709f3bc92c6daaf177cd7e3446da2ef64426c6 upstream.

Newer gcc are being a bit blind here (it's pretty obvious we don't
reach the code path using the array if we haven't initialized the
pointer) but none of that is performance critical so let's just
silence it.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
alpha: makefile: don't enforce small data model for kernel builds

commit cd8d2331756751b6aeb855a3c9cb0a92fbd9c725 upstream.

Due to all of the goodness being packed into today's kernels, the
resulting image isn't as slim as it once was.

In light of this, don't pass -msmall-data to gcc, which otherwise results
in link failures due to impossible relocations when compiling anything but
the most trivial configurations.

Reviewed-by: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Tested-by: Thorsten Kranzkowski <dl8bcu@dl8bcu.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Michael Cree <mcree@orcon.net.nz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
md/raid1,raid10: use freeze_array in place of raise_barrier in various places.

commit e2d59925221cd562e07fee38ec8839f7209ae603 upstream.

Various places in raid1 and raid10 are calling raise_barrier when they
really should call freeze_array.
The former is only intended to be called from "make_request".
The later has extra checks for 'nr_queued' and makes a call to
flush_pending_writes(), so it is safe to call it from within the
management thread.

Using raise_barrier will sometimes deadlock.  Using freeze_array
should not.

As 'freeze_array' currently expects one request to be pending (in
handle_read_error - the only previous caller), we need to pass
it the number of pending requests (extra) to ignore.

The deadlock was made particularly noticeable by commits
050b66152f87c7 (raid10) and 6b740b8d79252f13 (raid1) which
appeared in 3.4, so the fix is appropriate for any -stable
kernel since then.

This patch probably won't apply directly to some early kernels and
will need to be applied by hand.

Cc: stable@vger.kernel.org
Reported-by: Alexander Lyakas <alex.bolshoy@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
[adjust context to make it can be apply on top of 3.4 ]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sparc32: add ucmpdi2

commit de36e66d5fa52bc6e2dacd95c701a1762b5308a7 upstream.

Based on copy from microblaze add ucmpdi2 implementation.
This fixes build of niu driver which failed with:

drivers/built-in.o: In function `niu_get_nfc':
niu.c:(.text+0x91494): undefined reference to `__ucmpdi2'

This driver will never be used on a sparc32 system,
but patch added to fix build breakage with all*config builds.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sparc32: Add ucmpdi2.o to obj-y instead of lib-y.

commit 74c7b28953d4eaa6a479c187aeafcfc0280da5e8 upstream.

Otherwise if no references exist in the static kernel image,
we won't export the symbol properly to modules.

Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
MIPS: Rewrite pfn_valid to work in modules, too.

Upstream commit 8b9232141bf40788cce31f893c13f344ec31ee66.

This fixes:

  MODPOST 393 modules
ERROR: "min_low_pfn" [arch/mips/kvm/kvm.ko] undefined!
make[3]: *** [__modpost] Error 1

It would have been possible to just export min_low_pfn but in the end
pfn_valid should return 1 for any pfn argument for which a struct page
exists so using min_low_pfn was wrong anyway.

[Backport to 3.4 kernel. Applies cleanly on top of current 3.4 patch queue,
and fixes "make ARCH=mips allmodconfig; make ARCH=mips" build problem. - Guenter]

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>