Commit Graph

414561 Commits

Author SHA1 Message Date
Peter Zijlstra c026b3591e x86, mm, perf: Allow recursive faults from interrupts
Waiman managed to trigger a PMI while in a emulate_vsyscall() fault,
the PMI in turn managed to trigger a fault while obtaining a stack
trace. This triggered the sig_on_uaccess_error recursive fault logic
and killed the process dead.

Fix this by explicitly excluding interrupts from the recursive fault
logic.

Reported-and-Tested-by: Waiman Long <waiman.long@hp.com>
Fixes: e00b12e64b ("perf/x86: Further optimize copy_from_user_nmi()")
Cc: Aswin Chandramouleeswaran <aswin@hp.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140110200603.GJ7572@laptop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-01-16 09:19:48 +01:00
Linus Torvalds 85ce70fdf4 Merge branches 'sched-urgent-for-linus' and 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler and timer fixes from Ingo Molnar:
 "Contains a fix for a scheduler bug that manifested itself as a 3D
  performance regression and a crash fix for the ARM Cadence TTC clock
  driver"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Calculate effective load even if local weight is 0

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: cadence_ttc: Fix mutex taken inside interrupt context
2014-01-16 08:33:21 +07:00
Linus Torvalds 9b6c4ea95f Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
 "Two fixes from lockdep coverage of seqlocks, which fix deadlocks on
  lockdep-enabled ARM systems"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched_clock: Disable seqlock lockdep usage in sched_clock()
  seqlock: Use raw_ prefix instead of _no_lockdep
2014-01-16 08:31:55 +07:00
Linus Torvalds 93a11c8f5c hwmon fixes for 3.13 final
Fix attribute length problem in coretemp driver
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Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fix from Guenter Roeck:
 "Fix attribute length problem in coretemp driver"

* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (coretemp) Fix truncated name of alarm attributes
2014-01-16 08:26:44 +07:00
Linus Torvalds 9826dbb1e9 Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull ARM fixes from Russell King:
 "Another few fixes for ARM, nothing major here"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: 7938/1: OMAP4/highbank: Flush L2 cache before disabling
  ARM: 7939/1: traps: fix opcode endianness when read from user memory
  ARM: 7937/1: perf_event: Silence sparse warning
  ARM: 7934/1: DT/kernel: fix arch_match_cpu_phys_id to avoid erroneous match
  Revert "ARM: 7908/1: mm: Fix the arm_dma_limit calculation"
2014-01-16 08:26:00 +07:00
Linus Torvalds 70b23ce347 fix data corruption on NFS writeback
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Merge tag 'writeback-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux

Pull writeback fix from Wu Fengguang:
 "Fix data corruption on NFS writeback.

  It has been in linux-next for one month"

* tag 'writeback-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
  writeback: Fix data corruption on NFS
2014-01-16 08:23:34 +07:00
Linus Torvalds a9bdddb8dd Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c bugfix from Wolfram Sang.

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: Re-instate body of i2c_parent_is_i2c_adapter()
2014-01-16 08:21:17 +07:00
Eric Dumazet aee636c480 bpf: do not use reciprocal divide
At first Jakub Zawadzki noticed that some divisions by reciprocal_divide
were not correct. (off by one in some cases)
http://www.wireshark.org/~darkjames/reciprocal-buggy.c

He could also show this with BPF:
http://www.wireshark.org/~darkjames/set-and-dump-filter-k-bug.c

The reciprocal divide in linux kernel is not generic enough,
lets remove its use in BPF, as it is not worth the pain with
current cpus.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jakub Zawadzki <darkjames-ws@darkjames.pl>
Cc: Mircea Gherzan <mgherzan@gmail.com>
Cc: Daniel Borkmann <dxchgb@gmail.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Matt Evans <matt@ozlabs.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-15 17:02:08 -08:00
Ivan Vecera ba42fad096 be2net: add dma_mapping_error() check for dma_map_page()
The driver does not check value returned by dma_map_page. The patch
fixes this.

v2: Removed the bugfix for non-bug ;-) (thanks Sathya)

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Acked-by: Sathya Perla <Sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-15 16:50:32 -08:00
Yuval Mintz d9aee591b0 bnx2x: Don't release PCI bars on shutdown
The bnx2x driver in its pci shutdown() callback releases its pci bars (in the
same manner it does during its pci remove() callback).
During a system reboot while VFs are enabled, its possible for the VF's remove
to be called (as a result of pci_disable_sriov()) after its shutdown callback
has already finished running; This will cause a paging request fault as the VF
tries to access the pci bar which it has previously released, crashing the
system.

This patch further differentiates the shutdown and remove callbacks, preventing the
pci release procedures from being called during shutdown.

Signed-off-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Ariel Elior <ariele@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-15 16:48:34 -08:00
Richard Weinberger a926592f5e net,via-rhine: Fix tx_timeout handling
rhine_reset_task() misses to disable the tx scheduler upon reset,
this can lead to a crash if work is still scheduled while we're resetting
the tx queue.

Fixes:
[   93.591707] BUG: unable to handle kernel NULL pointer dereference at 0000004c
[   93.595514] IP: [<c119d10d>] rhine_napipoll+0x491/0x6

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-15 15:21:08 -08:00
Marek Lindner 1df0cbd509 batman-adv: fix batman-adv header overhead calculation
Batman-adv prepends a full ethernet header in addition to its own
header. This has to be reflected in the MTU calculation, especially
since the value is used to set dev->hard_header_len.

Introduced by 411d6ed93a
("batman-adv: consider network coding overhead when calculating required mtu")

Reported-by: cmsv <cmsv@wirelesspt.net>
Reported-by: Martin Hundebøll <martin@hundeboll.net>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
2014-01-15 23:54:20 +01:00
Andrew Jones 0dce7cd67f kvm: x86: fix apic_base enable check
Commit e66d2ae7c6 moved the assignment
vcpu->arch.apic_base = value above a condition with
(vcpu->arch.apic_base ^ value), causing that check
to always fail. Use old_value, vcpu->arch.apic_base's
old value, in the condition instead.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-01-15 13:42:14 +01:00
Linus Torvalds 2e67c56248 Merge branch 'akpm' (incoming from Andrew)
Merge patches from Andrew Morton:
 "Six fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  lib/percpu_counter.c: fix __percpu_counter_add()
  crash_dump: fix compilation error (on MIPS at least)
  mm: fix crash when using XFS on loopback
  MIPS: fix blast_icache32 on loongson2
  MIPS: fix case mismatch in local_r4k_flush_icache_range()
  nilfs2: fix segctor bug that causes file system corruption
2014-01-15 15:42:11 +07:00
Linus Torvalds 1a60864fc1 md: half a dozen bug fixes for 3.13
All of these fix real bugs the people have hit, and are tagged
 for -stable.
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Merge tag 'md/3.13-fixes' of git://neil.brown.name/md

Pull late md fixes from Neil Brown:
 "Half a dozen md bug fixes.

  All of these fix real bugs the people have hit, and are tagged for
  -stable.  Sorry they are late ....  Christmas holidays and all that.
  Hopefully they can still squeak into 3.13"

* tag 'md/3.13-fixes' of git://neil.brown.name/md:
  md: fix problem when adding device to read-only array with bitmap.
  md/raid10: fix bug when raid10 recovery fails to recover a block.
  md/raid5: fix a recently broken BUG_ON().
  md/raid1: fix request counting bug in new 'barrier' code.
  md/raid10: fix two bugs in handling of known-bad-blocks.
  md/raid5: Fix possible confusion when multiple write errors occur.
2014-01-15 15:07:36 +07:00
Linus Torvalds 145830dfb0 Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
 "One nouveau regression fix on older cards, i915 black screen fixes,
  and a revert for a strange G33 intel problem"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/nouveau: fix null ptr dereferences on some boards
  Revert "drm: copy mode type in drm_mode_connector_list_update()"
  drm/i915/bdw: make sure south port interrupts are enabled properly v2
  drm/i915: Don't grab crtc mutexes in intel_modeset_gem_init()
  drm/i915: fix DDI PLLs HW state readout code
2014-01-15 15:06:14 +07:00
Ming Lei 74e72f894d lib/percpu_counter.c: fix __percpu_counter_add()
__percpu_counter_add() may be called in softirq/hardirq handler (such
as, blk_mq_queue_exit() is typically called in hardirq/softirq handler),
so we need to call this_cpu_add()(irq safe helper) to update percpu
counter, otherwise counts may be lost.

This fixes the problem that 'rmmod null_blk' hangs in blk_cleanup_queue()
because of miscounting of request_queue->mq_usage_counter.

This patch is the v1 of previous one of "lib/percpu_counter.c:
disable local irq when updating percpu couter", and takes Andrew's
approach which may be more efficient for ARCHs(x86, s390) that
have optimized this_cpu_add().

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Shaohua Li <shli@fusionio.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Fan Du <fan.du@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-15 14:19:42 +07:00
Qais Yousef 5a610fcc73 crash_dump: fix compilation error (on MIPS at least)
In file included from kernel/crash_dump.c:2:0:
  include/linux/crash_dump.h:22:27: error: unknown type name `pgprot_t'

when CONFIG_CRASH_DUMP=y

The error was traced back to commit 9cb218131d ("vmcore: introduce
remap_oldmem_pfn_range()")

include <asm/pgtable.h> to get the missing definition

Signed-off-by: Qais Yousef <qais.yousef@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: <stable@vger.kernel.org>	[3.12+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-15 14:19:42 +07:00
Mikulas Patocka 03e5ac2fc3 mm: fix crash when using XFS on loopback
Commit 8456a648cf ("slab: use struct page for slab management") causes
a crash in the LVM2 testsuite on PA-RISC (the crashing test is
fsadm.sh).  The testsuite doesn't crash on 3.12, crashes on 3.13-rc1 and
later.

 Bad Address (null pointer deref?): Code=15 regs=000000413edd89a0 (Addr=000006202224647d)
 CPU: 3 PID: 24008 Comm: loop0 Not tainted 3.13.0-rc6 #5
 task: 00000001bf3c0048 ti: 000000413edd8000 task.ti: 000000413edd8000

      YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI
 PSW: 00001000000001101111100100001110 Not tainted
 r00-03  000000ff0806f90e 00000000405c8de0 000000004013e6c0 000000413edd83f0
 r04-07  00000000405a95e0 0000000000000200 00000001414735f0 00000001bf349e40
 r08-11  0000000010fe3d10 0000000000000001 00000040829c7778 000000413efd9000
 r12-15  0000000000000000 000000004060d800 0000000010fe3000 0000000010fe3000
 r16-19  000000413edd82a0 00000041078ddbc0 0000000000000010 0000000000000001
 r20-23  0008f3d0d83a8000 0000000000000000 00000040829c7778 0000000000000080
 r24-27  00000001bf349e40 00000001bf349e40 202d66202224640d 00000000405a95e0
 r28-31  202d662022246465 000000413edd88f0 000000413edd89a0 0000000000000001
 sr00-03  000000000532c000 0000000000000000 0000000000000000 000000000532c000
 sr04-07  0000000000000000 0000000000000000 0000000000000000 0000000000000000

 IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000401fe42c 00000000401fe430
  IIR: 539c0030    ISR: 00000000202d6000  IOR: 000006202224647d
  CPU:        3   CR30: 000000413edd8000 CR31: 0000000000000000
  ORIG_R28: 00000000405a95e0
  IAOQ[0]: vma_interval_tree_iter_first+0x14/0x48
  IAOQ[1]: vma_interval_tree_iter_first+0x18/0x48
  RP(r2): flush_dcache_page+0x128/0x388
 Backtrace:
   flush_dcache_page+0x128/0x388
   lo_splice_actor+0x90/0x148 [loop]
   splice_from_pipe_feed+0xc0/0x1d0
   __splice_from_pipe+0xac/0xc0
   lo_direct_splice_actor+0x1c/0x70 [loop]
   splice_direct_to_actor+0xec/0x228
   lo_receive+0xe4/0x298 [loop]
   loop_thread+0x478/0x640 [loop]
   kthread+0x134/0x168
   end_fault_vector+0x20/0x28
   xfs_setsize_buftarg+0x0/0x90 [xfs]

 Kernel panic - not syncing: Bad Address (null pointer deref?)

Commit 8456a648cf changes the page structure so that the slab
subsystem reuses the page->mapping field.

The crash happens in the following way:
 * XFS allocates some memory from slab and issues a bio to read data
   into it.
 * the bio is sent to the loopback device.
 * lo_receive creates an actor and calls splice_direct_to_actor.
 * lo_splice_actor copies data to the target page.
 * lo_splice_actor calls flush_dcache_page because the page may be
   mapped by userspace.  In that case we need to flush the kernel cache.
 * flush_dcache_page asks for the list of userspace mappings, however
   that page->mapping field is reused by the slab subsystem for a
   different purpose.  This causes the crash.

Note that other architectures without coherent caches (sparc, arm, mips)
also call page_mapping from flush_dcache_page, so they may crash in the
same way.

This patch fixes this bug by testing if the page is a slab page in
page_mapping and returning NULL if it is.

The patch also fixes VM_BUG_ON(PageSlab(page)) that could happen in
earlier kernels in the same scenario on architectures without cache
coherence when CONFIG_DEBUG_VM is enabled - so it should be backported
to stable kernels.

In the old kernels, the function page_mapping is placed in
include/linux/mm.h, so you should modify the patch accordingly when
backporting it.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: John David Anglin <dave.anglin@bell.net>]
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-15 14:19:42 +07:00
Aaro Koskinen 43a06847b9 MIPS: fix blast_icache32 on loongson2
Commit 14bd8c0820 ("MIPS: Loongson: Get rid of Loongson 2 #ifdefery
all over arch/mips") failed to add Loongson2 specific blast_icache32
functions.  Fix that.

The patch fixes the following crash seen with 3.13-rc1:

  Reserved instruction in kernel code[#1]:
  [...]
  Call Trace:
    blast_icache32_page+0x8/0xb0
    r4k_flush_cache_page+0x19c/0x200
    do_wp_page.isra.97+0x47c/0xe08
    handle_mm_fault+0x938/0x1118
    __do_page_fault+0x140/0x540
    resume_userspace_check+0x0/0x10
  Code: 00200825  64834000  00200825 <bc900000> bc900020  bc900040  bc900060  bc900080  bc9000a0

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Acked-by: John Crispin <blogic@openwrt.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-15 14:19:42 +07:00
Huacai Chen bad009fe35 MIPS: fix case mismatch in local_r4k_flush_icache_range()
Currently, Loongson-2 call protected_blast_icache_range() and others
call protected_loongson23_blast_icache_range(), but I think the correct
behavior should be the opposite.  BTW, Loongson-3's cache-ops is
compatible with MIPS64, but not compatible with Loongson-2.  So, rename
xxx_loongson23_yyy things to xxx_loongson2_yyy.

The patch fixes early boot hang with 3.13-rc1, introduced in commit
14bd8c0820 ("MIPS: Loongson: Get rid of Loongson 2 #ifdefery all over
arch/mips").

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Acked-by: John Crispin <blogic@openwrt.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-15 14:19:42 +07:00
Andreas Rohner 70f2fe3a26 nilfs2: fix segctor bug that causes file system corruption
There is a bug in the function nilfs_segctor_collect, which results in
active data being written to a segment, that is marked as clean.  It is
possible, that this segment is selected for a later segment
construction, whereby the old data is overwritten.

The problem shows itself with the following kernel log message:

  nilfs_sufile_do_cancel_free: segment 6533 must be clean

Usually a few hours later the file system gets corrupted:

  NILFS: bad btree node (blocknr=8748107): level = 0, flags = 0x0, nchildren = 0
  NILFS error (device sdc1): nilfs_bmap_last_key: broken bmap (inode number=114660)

The issue can be reproduced with a file system that is nearly full and
with the cleaner running, while some IO intensive task is running.
Although it is quite hard to reproduce.

This is what happens:

 1. The cleaner starts the segment construction
 2. nilfs_segctor_collect is called
 3. sc_stage is on NILFS_ST_SUFILE and segments are freed
 4. sc_stage is on NILFS_ST_DAT current segment is full
 5. nilfs_segctor_extend_segments is called, which
    allocates a new segment
 6. The new segment is one of the segments freed in step 3
 7. nilfs_sufile_cancel_freev is called and produces an error message
 8. Loop around and the collection starts again
 9. sc_stage is on NILFS_ST_SUFILE and segments are freed
    including the newly allocated segment, which will contain active
    data and can be allocated at a later time
10. A few hours later another segment construction allocates the
    segment and causes file system corruption

This can be prevented by simply reordering the statements.  If
nilfs_sufile_cancel_freev is called before nilfs_segctor_extend_segments
the freed segments are marked as dirty and cannot be allocated any more.

Signed-off-by: Andreas Rohner <andreas.rohner@gmx.net>
Reviewed-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: Andreas Rohner <andreas.rohner@gmx.net>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-15 14:19:42 +07:00
Ingo Molnar e59da0aedb Merge branch 'clockevents/3.13-fixes' of git://git.linaro.org/people/daniel.lezcano/linux into timers/urgent
Pull clock driver fix from Daniel Lezcano:

 " * Soren Brinkmann fixed the cadence_ttc driver where a call to
     clk_get_rate happens in an interrupt context. More precisely in an IPI
     when the broadcast timer is initialized for each cpu in the cpuidle
     driver. "

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-01-15 07:39:30 +01:00
Dave Airlie 703a8c2dfa Merge branch 'drm-nouveau-next' of git://git.freedesktop.org/git/nouveau/linux-2.6 into drm-fixes
Single regression fix for nouveau

* 'drm-nouveau-next' of git://git.freedesktop.org/git/nouveau/linux-2.6:
  drm/nouveau: fix null ptr dereferences on some boards
2014-01-15 15:01:11 +10:00
Ben Skeggs fdd239ac99 drm/nouveau: fix null ptr dereferences on some boards
Regression from "device: populate master subdev pointer only when fully
constructed"

Reported-by: Bob Gleitsmann <rjgleits@bellsouth.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
2014-01-15 14:24:05 +10:00
Jitendra Kalsaria 51bb352f15 qlge: Fix vlan netdev features.
vlan gets the same netdev features except vlan filter.

Signed-off-by: Jitendra Kalsaria <jitendra.kalsaria@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-14 19:02:35 -08:00
Hannes Frederic Sowa 95f4a45de1 net: avoid reference counter overflows on fib_rules in multicast forwarding
Bob Falken reported that after 4G packets, multicast forwarding stopped
working. This was because of a rule reference counter overflow which
freed the rule as soon as the overflow happend.

This patch solves this by adding the FIB_LOOKUP_NOREF flag to
fib_rules_lookup calls. This is safe even from non-rcu locked sections
as in this case the flag only implies not taking a reference to the rule,
which we don't need at all.

Rules only hold references to the namespace, which are guaranteed to be
available during the call of the non-rcu protected function reg_vif_xmit
because of the interface reference which itself holds a reference to
the net namespace.

Fixes: f0ad0860d0 ("ipv4: ipmr: support multiple tables")
Fixes: d1db275dd3 ("ipv6: ip6mr: support multiple tables")
Reported-by: Bob Falken <NetFestivalHaveFun@gmx.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Julian Anastasov <ja@ssi.bg>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-14 17:37:25 -08:00
Peter Korsgaard 7c4b5175f6 dm9601: add USB IDs for new dm96xx variants
A number of new dm96xx variants now exist.

Reported-by: Joseph Chang <joseph_chang@davicom.com.tw>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-14 17:36:19 -08:00
Michael S. Tsirkin a02bbb1ccf MAINTAINERS: add virtio-dev ML for virtio
Since virtio is an OASIS standard draft now, virtio implementation
discussions are taking place on the virtio-dev OASIS mailing list.
Update MAINTAINERS.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-14 17:09:38 -08:00
Christian Engelmayer 267d29a69c ieee802154: Fix memory leak in ieee802154_add_iface()
Fix a memory leak in the ieee802154_add_iface() error handling path.
Detected by Coverity: CID 710490.

Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-14 15:40:56 -08:00
Jean Delvare 3f9aec7610 hwmon: (coretemp) Fix truncated name of alarm attributes
When the core number exceeds 9, the size of the buffer storing the
alarm attribute name is insufficient and the attribute name is
truncated. This causes libsensors to skip these attributes as the
truncated name is not recognized.

Reported-by: Andreas Hollmann <hollmann@in.tum.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: stable@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2014-01-14 09:47:52 -08:00
Stephen Warren 2fac2b891f i2c: Re-instate body of i2c_parent_is_i2c_adapter()
The body of i2c_parent_is_i2c_adapter() is currently guarded by
I2C_MUX. It should be CONFIG_I2C_MUX instead.

Among potentially other problems, this resulted in i2c_lock_adapter()
only locking I2C mux child adapters, and not the parent adapter. In
turn, this could allow inter-mingling of mux child selection and I2C
transactions, which could result in I2C transactions being directed to
the wrong I2C bus, and possibly even switching between busses in the
middle of a transaction.

One concrete issue caused by this bug was corrupted HDMI EDID reads
during boot on the NVIDIA Tegra Seaboard system, although this only
became apparent in recent linux-next, when the boot timing was changed
just enough to trigger the race condition.

Fixes: 3923172b3d ("i2c: reduce parent checking to a NOOP in non-I2C_MUX case")
Cc: Phil Carmody <phil.carmody@partner.samsung.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-14 17:11:13 +01:00
Bjørn Mork fdc3452cd2 net: usbnet: fix SG initialisation
Commit 60e453a940 ("USBNET: fix handling padding packet")
added an extra SG entry in case padding is necessary, but
failed to update the initialisation of the list. This can
cause list traversal to fall off the end of the list,
resulting in an oops.

Fixes: 60e453a940 ("USBNET: fix handling padding packet")
Reported-by: Thomas Kear <thomas@kear.co.nz>
Cc: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Tested-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13 23:32:04 -08:00
Neal Cardwell 70315d22d3 inet_diag: fix inet_diag_dump_icsk() to use correct state for timewait sockets
Fix inet_diag_dump_icsk() to reflect the fact that both TCP_TIME_WAIT
and TCP_FIN_WAIT2 connections are represented by inet_timewait_sock
(not just TIME_WAIT), and for such sockets the tw_substate field holds
the real state, which can be either TCP_TIME_WAIT or TCP_FIN_WAIT2.

This brings the inet_diag state-matching code in line with the field
it uses to populate idiag_state. This is also analogous to the info
exported in /proc/net/tcp, where get_tcp4_sock() exports sk->sk_state
and get_timewait4_sock() exports tw->tw_substate.

Before fixing this, (a) neither "ss -nemoi" nor "ss -nemoi state
fin-wait-2" would return a socket in TCP_FIN_WAIT2; and (b) "ss -nemoi
state time-wait" would also return sockets in state TCP_FIN_WAIT2.

This is an old bug that predates 05dbc7b ("tcp/dccp: remove twchain").

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13 22:35:46 -08:00
NeilBrown 8313b8e57f md: fix problem when adding device to read-only array with bitmap.
If an array is started degraded, and then the missing device
is found it can be re-added and a minimal bitmap-based recovery
will bring it fully up-to-date.

If the array is read-only a recovery would not be allowed.
But also if the array is read-only and the missing device was
present very recently, then there could be no need for any
recovery at all, so we simply include the device in the read-only
array without any recovery.

However... if the missing device was removed a little longer ago
it could be missing some updates, but if a bitmap is present it will
be conditionally accepted pending a bitmap-based update.  We don't
currently detect this case properly and will include that old
device into the read-only array with no recovery even though it really
needs a recovery.

This patch keeps track of whether a bitmap-based-recovery is really
needed or not in the new Bitmap_sync rdev flag.  If that is set,
then the device will not be added to a read-only array.

Cc: Andrei Warkentin <andreiw@vmware.com>
Fixes: d70ed2e4fa
Cc: stable@vger.kernel.org (3.2+)
Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14 16:44:08 +11:00
NeilBrown e8b8491585 md/raid10: fix bug when raid10 recovery fails to recover a block.
commit e875ecea26
    md/raid10 record bad blocks as needed during recovery.

added code to the "cannot recover this block" path to record a bad
block rather than fail the whole recovery.
Unfortunately this new case was placed *after* r10bio was freed rather
than *before*, yet it still uses r10bio.
This is will crash with a null dereference.

So move the freeing of r10bio down where it is safe.

Cc: stable@vger.kernel.org (v3.1+)
Fixes: e875ecea26
Reported-by: Damian Nowak <spam@nowaker.net>
URL: https://bugzilla.kernel.org/show_bug.cgi?id=68181
Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14 16:44:08 +11:00
NeilBrown 5af9bef72c md/raid5: fix a recently broken BUG_ON().
commit 6d183de407
    md/raid5: fix newly-broken locking in get_active_stripe.

simplified a BUG_ON, but removed too much so now it sometimes fires
when it shouldn't.

When the STRIPE_EXPANDING flag is set, the stripe_head might be on a
special list while multiple stripe_heads are collected, or it might
not be on any list, even a 'free' list when the refcount is zero.  As
long as STRIPE_EXPANDING is set, it will be found and added back to a
list eventually.

So both of the BUG_ONs which test for the ->lru being empty or not
need to avoid the case where STRIPE_EXPANDING is set.

The patch which broke this was marked for -stable, so this patch needs
to be applied to any branch that received 6d183de4

Fixes: 6d183de407
Cc: stable@vger.kernel.org (any release to which above was applied)
Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14 16:44:07 +11:00
NeilBrown 41a336e011 md/raid1: fix request counting bug in new 'barrier' code.
The new iobarrier implementation in raid1 (which keeps normal writes
and resync activity separate) counts every request what is not before
the current resync point in either next_window_requests or
current_window_requests.
It flags that the request is counted by setting ->start_next_window.

allow_barrier follows this model exactly and decrements one of the
*_window_requests if and only if ->start_next_window is set.

However wait_barrier(), which increments *_window_requests uses a
slightly different test for setting -.start_next_window (which is set
from the return value of this function).
So there is a possibility of the counts getting out of sync, and this
leads to the resync hanging.

So change wait_barrier() to return a non-zero value in exactly the
same cases that it increments *_window_requests.

But was introduced in 3.13-rc1.

Reported-by: Bruno Wolff III <bruno@wolff.to>
URL: https://bugzilla.kernel.org/show_bug.cgi?id=68061
Fixes: 79ef3a8aa1
Cc: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14 16:44:07 +11:00
NeilBrown b50c259e25 md/raid10: fix two bugs in handling of known-bad-blocks.
If we discover a bad block when reading we split the request and
potentially read some of it from a different device.

The code path of this has two bugs in RAID10.
1/ we get a spin_lock with _irq, but unlock without _irq!!
2/ The calculation of 'sectors_handled' is wrong, as can be clearly
   seen by comparison with raid1.c

This leads to at least 2 warnings and a probable crash is a RAID10
ever had known bad blocks.

Cc: stable@vger.kernel.org (v3.1+)
Fixes: 856e08e237
Reported-by: Damian Nowak <spam@nowaker.net>
URL: https://bugzilla.kernel.org/show_bug.cgi?id=68181
Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14 16:44:07 +11:00
NeilBrown 1cc03eb932 md/raid5: Fix possible confusion when multiple write errors occur.
commit 5d8c71f9e5
    md: raid5 crash during degradation

Fixed a crash in an overly simplistic way which could leave
R5_WriteError or R5_MadeGood set in the stripe cache for devices
for which it is no longer relevant.
When those devices are removed and spares added the flags are still
set and can cause incorrect behaviour.

commit 14a75d3e07
    md/raid5: preferentially read from replacement device if possible.

Fixed the same bug if a more effective way, so we can now revert
the original commit.

Reported-and-tested-by: Alexander Lyakas <alex.bolshoy@gmail.com>
Cc: stable@vger.kernel.org (3.2+ - 3.2 will need a different fix though)
Fixes: 5d8c71f9e5
Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14 16:44:07 +11:00
Dave Airlie abce1ec9b0 Revert "drm: copy mode type in drm_mode_connector_list_update()"
This reverts commit 3fbd6439e4.

This caused some strange booting lockup issues on an Intel G33
belonging to Daniel Vetter, very unusual, I was hoping Daniel
would track this down, but it looks like instead I'll have to hack
a different fix for -next.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-01-14 12:50:49 +10:00
Dave Airlie c0eeb856e9 Merge tag 'drm-intel-fixes-2014-01-13' of git://people.freedesktop.org/~danvet/drm-intel into drm-fixes
Black screen fixes, one for hsw+bdw each and a regression fix for
locking+load detection.

* tag 'drm-intel-fixes-2014-01-13' of git://people.freedesktop.org/~danvet/drm-intel:
  drm/i915/bdw: make sure south port interrupts are enabled properly v2
  drm/i915: Don't grab crtc mutexes in intel_modeset_gem_init()
  drm/i915: fix DDI PLLs HW state readout code
2014-01-14 12:44:48 +10:00
Dan Carpenter 9ef9730ba8 cxgb4: silence shift wrapping static checker warning
I don't know how large "tp->vlan_shift" is but static checkers worry
about shift wrapping bugs here.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Dimitris Michailidis <dm@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13 11:15:58 -08:00
Linus Torvalds a6da83f982 Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull powerpc fix from Ben Herrenschmidt:
 "Here's one regression fix for 3.13 that I would appreciate if you
  could still pull in.  It was an "interesting" one to debug, basically
  it's an old bug that got somewhat "exposed" by new code breaking the
  boot on PA Semi boards (yes, it does appear that some people are still
  using these!)"

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc: Check return value of instance-to-package OF call
2014-01-13 10:59:05 +07:00
Linus Torvalds 061f49ec2d Merge branch 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Peter Anvin:
 "Sorry, meant to push out this batch earlier this weekend"

* 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, fpu, amd: Clear exceptions in AMD FXSAVE workaround
  ftrace/x86: Load ftrace_ops in parameter not the variable holding it
2014-01-13 07:28:49 +07:00
Benjamin Herrenschmidt 10348f5976 powerpc: Check return value of instance-to-package OF call
On PA-Semi firmware, the instance-to-package callback doesn't seem
to be implemented. We didn't check for error, however, thus
subsequently passed the -1 value returned into stdout_node to
thins like prom_getprop etc...

Thus caused the firmware to load values around 0 (physical) internally
as node structures. It somewhat "worked" as long as we had a NULL in the
right place (address 8) at the beginning of the kernel, we didn't "see"
the bug. But commit 5c0484e25e
"powerpc: Endian safe trampoline" changed the kernel entry point causing
that old bug to now cause a crash early during boot.

This fixes booting on PA-Semi board by properly checking the return
value from instance-to-package.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Olof Johansson <olof@lixom.net>
---
2014-01-13 09:49:17 +11:00
Taras Kondratiuk b25f3e1c35 ARM: 7938/1: OMAP4/highbank: Flush L2 cache before disabling
Kexec disables outer cache before jumping to reboot code, but it doesn't
flush it explicitly. Flush is done implicitly inside of l2x0_disable().
But some SoC's override default .disable handler and don't flush cache.
This may lead to a corrupted memory during Kexec reboot on these
platforms.

This patch adds cache flush inside of OMAP4 and Highbank outer_cache.disable()
handlers to make it consistent with default l2x0_disable().

Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-01-12 14:15:27 +00:00
Linus Torvalds 7e22e91102 Linux 3.13-rc8 2014-01-12 17:04:18 +07:00
Steven Rostedt 3dc91d4338 SELinux: Fix possible NULL pointer dereference in selinux_inode_permission()
While running stress tests on adding and deleting ftrace instances I hit
this bug:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
  IP: selinux_inode_permission+0x85/0x160
  PGD 63681067 PUD 7ddbe067 PMD 0
  Oops: 0000 [#1] PREEMPT
  CPU: 0 PID: 5634 Comm: ftrace-test-mki Not tainted 3.13.0-rc4-test-00033-gd2a6dde-dirty #20
  Hardware name:                  /DG965MQ, BIOS MQ96510J.86A.0372.2006.0605.1717 06/05/2006
  task: ffff880078375800 ti: ffff88007ddb0000 task.ti: ffff88007ddb0000
  RIP: 0010:[<ffffffff812d8bc5>]  [<ffffffff812d8bc5>] selinux_inode_permission+0x85/0x160
  RSP: 0018:ffff88007ddb1c48  EFLAGS: 00010246
  RAX: 0000000000000000 RBX: 0000000000800000 RCX: ffff88006dd43840
  RDX: 0000000000000001 RSI: 0000000000000081 RDI: ffff88006ee46000
  RBP: ffff88007ddb1c88 R08: 0000000000000000 R09: ffff88007ddb1c54
  R10: 6e6576652f6f6f66 R11: 0000000000000003 R12: 0000000000000000
  R13: 0000000000000081 R14: ffff88006ee46000 R15: 0000000000000000
  FS:  00007f217b5b6700(0000) GS:ffffffff81e21000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033^M
  CR2: 0000000000000020 CR3: 000000006a0fe000 CR4: 00000000000007f0
  Call Trace:
    security_inode_permission+0x1c/0x30
    __inode_permission+0x41/0xa0
    inode_permission+0x18/0x50
    link_path_walk+0x66/0x920
    path_openat+0xa6/0x6c0
    do_filp_open+0x43/0xa0
    do_sys_open+0x146/0x240
    SyS_open+0x1e/0x20
    system_call_fastpath+0x16/0x1b
  Code: 84 a1 00 00 00 81 e3 00 20 00 00 89 d8 83 c8 02 40 f6 c6 04 0f 45 d8 40 f6 c6 08 74 71 80 cf 02 49 8b 46 38 4c 8d 4d cc 45 31 c0 <0f> b7 50 20 8b 70 1c 48 8b 41 70 89 d9 8b 78 04 e8 36 cf ff ff
  RIP  selinux_inode_permission+0x85/0x160
  CR2: 0000000000000020

Investigating, I found that the inode->i_security was NULL, and the
dereference of it caused the oops.

in selinux_inode_permission():

	isec = inode->i_security;

	rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);

Note, the crash came from stressing the deletion and reading of debugfs
files.  I was not able to recreate this via normal files.  But I'm not
sure they are safe.  It may just be that the race window is much harder
to hit.

What seems to have happened (and what I have traced), is the file is
being opened at the same time the file or directory is being deleted.
As the dentry and inode locks are not held during the path walk, nor is
the inodes ref counts being incremented, there is nothing saving these
structures from being discarded except for an rcu_read_lock().

The rcu_read_lock() protects against freeing of the inode, but it does
not protect freeing of the inode_security_struct.  Now if the freeing of
the i_security happens with a call_rcu(), and the i_security field of
the inode is not changed (it gets freed as the inode gets freed) then
there will be no issue here.  (Linus Torvalds suggested not setting the
field to NULL such that we do not need to check if it is NULL in the
permission check).

Note, this is a hack, but it fixes the problem at hand.  A real fix is
to restructure the destroy_inode() to call all the destructor handlers
from the RCU callback.  But that is a major job to do, and requires a
lot of work.  For now, we just band-aid this bug with this fix (it
works), and work on a more maintainable solution in the future.

Link: http://lkml.kernel.org/r/20140109101932.0508dec7@gandalf.local.home
Link: http://lkml.kernel.org/r/20140109182756.17abaaa8@gandalf.local.home

Cc: stable@vger.kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-12 16:53:13 +07:00
Hugh Dickins eecc1e426d thp: fix copy_page_rep GPF by testing is_huge_zero_pmd once only
We see General Protection Fault on RSI in copy_page_rep: that RSI is
what you get from a NULL struct page pointer.

  RIP: 0010:[<ffffffff81154955>]  [<ffffffff81154955>] copy_page_rep+0x5/0x10
  RSP: 0000:ffff880136e15c00  EFLAGS: 00010286
  RAX: ffff880000000000 RBX: ffff880136e14000 RCX: 0000000000000200
  RDX: 6db6db6db6db6db7 RSI: db73880000000000 RDI: ffff880dd0c00000
  RBP: ffff880136e15c18 R08: 0000000000000200 R09: 000000000005987c
  R10: 000000000005987c R11: 0000000000000200 R12: 0000000000000001
  R13: ffffea00305aa000 R14: 0000000000000000 R15: 0000000000000000
  FS:  00007f195752f700(0000) GS:ffff880c7fc20000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000093010000 CR3: 00000001458e1000 CR4: 00000000000027e0
  Call Trace:
    copy_user_huge_page+0x93/0xab
    do_huge_pmd_wp_page+0x710/0x815
    handle_mm_fault+0x15d8/0x1d70
    __do_page_fault+0x14d/0x840
    do_page_fault+0x2f/0x90
    page_fault+0x22/0x30

do_huge_pmd_wp_page() tests is_huge_zero_pmd(orig_pmd) four times: but
since shrink_huge_zero_page() can free the huge_zero_page, and we have
no hold of our own on it here (except where the fourth test holds
page_table_lock and has checked pmd_same), it's possible for it to
answer yes the first time, but no to the second or third test.  Change
all those last three to tests for NULL page.

(Note: this is not the same issue as trinity's DEBUG_PAGEALLOC BUG
in copy_page_rep with RSI: ffff88009c422000, reported by Sasha Levin
in https://lkml.org/lkml/2013/3/29/103.  I believe that one is due
to the source page being split, and a tail page freed, while copy
is in progress; and not a problem without DEBUG_PAGEALLOC, since
the pmd_same check will prevent a miscopy from being made visible.)

Fixes: 97ae17497e ("thp: implement refcounting for huge zero page")
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: stable@vger.kernel.org # v3.10 v3.11 v3.12
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-12 16:47:15 +07:00