Commit Graph

401415 Commits

Author SHA1 Message Date
Linus Torvalds 12aee278b5 Merge branch 'akpm' (fixes from Andrew Morton)
Merge three fixes from Andrew Morton.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  memcg: use __this_cpu_sub() to dec stats to avoid incorrect subtrahend casting
  percpu: fix this_cpu_sub() subtrahend casting for unsigneds
  mm/pagewalk.c: fix walk_page_range() access of wrong PTEs
2013-10-30 14:27:10 -07:00
Greg Thelen 5e8cfc3c75 memcg: use __this_cpu_sub() to dec stats to avoid incorrect subtrahend casting
As of commit 3ea67d06e4 ("memcg: add per cgroup writeback pages
accounting") memcg counter errors are possible when moving charged
memory to a different memcg.  Charge movement occurs when processing
writes to memory.force_empty, moving tasks to a memcg with
memcg.move_charge_at_immigrate=1, or memcg deletion.

An example showing error after memory.force_empty:

  $ cd /sys/fs/cgroup/memory
  $ mkdir x
  $ rm /data/tmp/file
  $ (echo $BASHPID >> x/tasks && exec mmap_writer /data/tmp/file 1M) &
  [1] 13600
  $ grep ^mapped x/memory.stat
  mapped_file 1048576
  $ echo 13600 > tasks
  $ echo 1 > x/memory.force_empty
  $ grep ^mapped x/memory.stat
  mapped_file 4503599627370496

mapped_file should end with 0.
  4503599627370496 == 0x10,0000,0000,0000 == 0x100,0000,0000 pages
  1048576          == 0x10,0000           == 0x100 pages

This issue only affects the source memcg on 64 bit machines; the
destination memcg counters are correct.  So the rmdir case is not too
important because such counters are soon disappearing with the entire
memcg.  But the memcg.force_empty and memory.move_charge_at_immigrate=1
cases are larger problems as the bogus counters are visible for the
(possibly long) remaining life of the source memcg.

The problem is due to memcg use of __this_cpu_from(.., -nr_pages), which
is subtly wrong because it subtracts the unsigned int nr_pages (either
-1 or -512 for THP) from a signed long percpu counter.  When
nr_pages=-1, -nr_pages=0xffffffff.  On 64 bit machines stat->count[idx]
is signed 64 bit.  So memcg's attempt to simply decrement a count (e.g.
from 1 to 0) boils down to:

  long count = 1
  unsigned int nr_pages = 1
  count += -nr_pages  /* -nr_pages == 0xffff,ffff */
  count is now 0x1,0000,0000 instead of 0

The fix is to subtract the unsigned page count rather than adding its
negation.  This only works once "percpu: fix this_cpu_sub() subtrahend
casting for unsigneds" is applied to fix this_cpu_sub().

Signed-off-by: Greg Thelen <gthelen@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-30 14:27:03 -07:00
Greg Thelen bd09d9a351 percpu: fix this_cpu_sub() subtrahend casting for unsigneds
this_cpu_sub() is implemented as negation and addition.

This patch casts the adjustment to the counter type before negation to
sign extend the adjustment.  This helps in cases where the counter type
is wider than an unsigned adjustment.  An alternative to this patch is
to declare such operations unsupported, but it seemed useful to avoid
surprises.

This patch specifically helps the following example:
  unsigned int delta = 1
  preempt_disable()
  this_cpu_write(long_counter, 0)
  this_cpu_sub(long_counter, delta)
  preempt_enable()

Before this change long_counter on a 64 bit machine ends with value
0xffffffff, rather than 0xffffffffffffffff.  This is because
this_cpu_sub(pcp, delta) boils down to this_cpu_add(pcp, -delta),
which is basically:
  long_counter = 0 + 0xffffffff

Also apply the same cast to:
  __this_cpu_sub()
  __this_cpu_sub_return()
  this_cpu_sub_return()

All percpu_test.ko passes, especially the following cases which
previously failed:

  l -= ui_one;
  __this_cpu_sub(long_counter, ui_one);
  CHECK(l, long_counter, -1);

  l -= ui_one;
  this_cpu_sub(long_counter, ui_one);
  CHECK(l, long_counter, -1);
  CHECK(l, long_counter, 0xffffffffffffffff);

  ul -= ui_one;
  __this_cpu_sub(ulong_counter, ui_one);
  CHECK(ul, ulong_counter, -1);
  CHECK(ul, ulong_counter, 0xffffffffffffffff);

  ul = this_cpu_sub_return(ulong_counter, ui_one);
  CHECK(ul, ulong_counter, 2);

  ul = __this_cpu_sub_return(ulong_counter, ui_one);
  CHECK(ul, ulong_counter, 1);

Signed-off-by: Greg Thelen <gthelen@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-30 14:27:03 -07:00
Chen LinX 3017f079ef mm/pagewalk.c: fix walk_page_range() access of wrong PTEs
When walk_page_range walk a memory map's page tables, it'll skip
VM_PFNMAP area, then variable 'next' will to assign to vma->vm_end, it
maybe larger than 'end'.  In next loop, 'addr' will be larger than
'next'.  Then in /proc/XXXX/pagemap file reading procedure, the 'addr'
will growing forever in pagemap_pte_range, pte_to_pagemap_entry will
access the wrong pte.

  BUG: Bad page map in process procrank  pte:8437526f pmd:785de067
  addr:9108d000 vm_flags:00200073 anon_vma:f0d99020 mapping:  (null) index:9108d
  CPU: 1 PID: 4974 Comm: procrank Tainted: G    B   W  O 3.10.1+ #1
  Call Trace:
    dump_stack+0x16/0x18
    print_bad_pte+0x114/0x1b0
    vm_normal_page+0x56/0x60
    pagemap_pte_range+0x17a/0x1d0
    walk_page_range+0x19e/0x2c0
    pagemap_read+0x16e/0x200
    vfs_read+0x84/0x150
    SyS_read+0x4a/0x80
    syscall_call+0x7/0xb

Signed-off-by: Liu ShuoX <shuox.liu@intel.com>
Signed-off-by: Chen LinX <linx.z.chen@intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: <stable@vger.kernel.org>	[3.10.x+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-30 14:27:03 -07:00
Russell King c56b097af2 mm: list_lru: fix almost infinite loop causing effective livelock
I've seen a fair number of issues with kswapd and other processes
appearing to get stuck in v3.12-rc.  Using sysrq-p many times seems to
indicate that it gets stuck somewhere in list_lru_walk_node(), called
from prune_icache_sb() and super_cache_scan().

I never seem to be able to trigger a calltrace for functions above that
point.

So I decided to add the following to super_cache_scan():

    @@ -81,10 +81,14 @@ static unsigned long super_cache_scan(struct shrinker *shrink,
            inodes = list_lru_count_node(&sb->s_inode_lru, sc->nid);
            dentries = list_lru_count_node(&sb->s_dentry_lru, sc->nid);
            total_objects = dentries + inodes + fs_objects + 1;
    +printk("%s:%u: %s: dentries %lu inodes %lu total %lu\n", current->comm, current->pid, __func__, dentries, inodes, total_objects);

            /* proportion the scan between the caches */
            dentries = mult_frac(sc->nr_to_scan, dentries, total_objects);
            inodes = mult_frac(sc->nr_to_scan, inodes, total_objects);
    +printk("%s:%u: %s: dentries %lu inodes %lu\n", current->comm, current->pid, __func__, dentries, inodes);
    +BUG_ON(dentries == 0);
    +BUG_ON(inodes == 0);

            /*
             * prune the dcache first as the icache is pinned by it, then
    @@ -99,7 +103,7 @@ static unsigned long super_cache_scan(struct shrinker *shrink,
                    freed += sb->s_op->free_cached_objects(sb, fs_objects,
                                                           sc->nid);
            }
    -
    +printk("%s:%u: %s: dentries %lu inodes %lu freed %lu\n", current->comm, current->pid, __func__, dentries, inodes, freed);
            drop_super(sb);
            return freed;
     }

and shortly thereafter, having applied some pressure, I got this:

    update-apt-xapi:1616: super_cache_scan: dentries 25632 inodes 2 total 25635
    update-apt-xapi:1616: super_cache_scan: dentries 1023 inodes 0
    ------------[ cut here ]------------
    Kernel BUG at c0101994 [verbose debug info unavailable]
    Internal error: Oops - BUG: 0 [#3] SMP ARM
    Modules linked in: fuse rfcomm bnep bluetooth hid_cypress
    CPU: 0 PID: 1616 Comm: update-apt-xapi Tainted: G      D      3.12.0-rc7+ #154
    task: daea1200 ti: c3bf8000 task.ti: c3bf8000
    PC is at super_cache_scan+0x1c0/0x278
    LR is at trace_hardirqs_on+0x14/0x18
    Process update-apt-xapi (pid: 1616, stack limit = 0xc3bf8240)
    ...
    Backtrace:
      (super_cache_scan) from [<c00cd69c>] (shrink_slab+0x254/0x4c8)
      (shrink_slab) from [<c00d09a0>] (try_to_free_pages+0x3a0/0x5e0)
      (try_to_free_pages) from [<c00c59cc>] (__alloc_pages_nodemask+0x5)
      (__alloc_pages_nodemask) from [<c00e07c0>] (__pte_alloc+0x2c/0x13)
      (__pte_alloc) from [<c00e3a70>] (handle_mm_fault+0x84c/0x914)
      (handle_mm_fault) from [<c001a4cc>] (do_page_fault+0x1f0/0x3bc)
      (do_page_fault) from [<c001a7b0>] (do_translation_fault+0xac/0xb8)
      (do_translation_fault) from [<c000840c>] (do_DataAbort+0x38/0xa0)
      (do_DataAbort) from [<c00133f8>] (__dabt_usr+0x38/0x40)

Notice that we had a very low number of inodes, which were reduced to
zero my mult_frac().

Now, prune_icache_sb() calls list_lru_walk_node() passing that number of
inodes (0) into that as the number of objects to scan:

    long prune_icache_sb(struct super_block *sb, unsigned long nr_to_scan,
                         int nid)
    {
            LIST_HEAD(freeable);
            long freed;

            freed = list_lru_walk_node(&sb->s_inode_lru, nid, inode_lru_isolate,
                                           &freeable, &nr_to_scan);

which does:

    unsigned long
    list_lru_walk_node(struct list_lru *lru, int nid, list_lru_walk_cb isolate,
                       void *cb_arg, unsigned long *nr_to_walk)
    {

            struct list_lru_node    *nlru = &lru->node[nid];
            struct list_head *item, *n;
            unsigned long isolated = 0;

            spin_lock(&nlru->lock);
    restart:
            list_for_each_safe(item, n, &nlru->list) {
                    enum lru_status ret;

                    /*
                     * decrement nr_to_walk first so that we don't livelock if we
                     * get stuck on large numbesr of LRU_RETRY items
                     */
                    if (--(*nr_to_walk) == 0)
                            break;

So, if *nr_to_walk was zero when this function was entered, that means
we're wanting to operate on (~0UL)+1 objects - which might as well be
infinite.

Clearly this is not correct behaviour.  If we think about the behaviour
of this function when *nr_to_walk is 1, then clearly it's wrong - we
decrement first and then test for zero - which results in us doing
nothing at all.  A post-decrement would give the desired behaviour -
we'd try to walk one object and one object only if *nr_to_walk were one.

It also gives the correct behaviour for zero - we exit at this point.

Fixes: 5cedf721a7 ("list_lru: fix broken LRU_RETRY behaviour")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
[ Modified to make sure we never underflow the count: this function gets
  called in a loop, so the 0 -> ~0ul transition is dangerous  - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-30 12:57:46 -07:00
Linus Torvalds ced5d6b552 Serial fixes for 3.12-final
Here are 3 tiny fixes that are needed for 3.12-final for some serial
 drivers.  One of them is a revert of a broken patch, and two others are
 fixes for reported bugs.  All of these have been in linux-next for a
 while, I forgot I had not sent them to you yet, my fault.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.19 (GNU/Linux)
 
 iEYEABECAAYFAlJxUPwACgkQMUfUDdst+ymzGgCfSmp/uQAOLnEKJ2WKfElDcbZM
 nhkAnRivp6JzwmFLVEIXORMcmLhyc8Nn
 =FOvb
 -----END PGP SIGNATURE-----

Merge tag 'tty-3.12-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull serial fixes from Greg KH:
 "Here are 3 tiny fixes that are needed for 3.12-final for some serial
  drivers.

  One of them is a revert of a broken patch, and two others are fixes
  for reported bugs.  All of these have been in linux-next for a while,
  I forgot I had not sent them to you yet, my fault"

(Actually, Greg, you _had_ sent two of the three, so this pulls in just
one actual new fix)

* tag 'tty-3.12-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty/serial: at91: fix uart/usart selection for older products
2013-10-30 12:29:06 -07:00
Linus Torvalds b8cab70665 Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
 "Mainly Intel regression fixes and quirks, along with a simple one
  liner to fix rendernodes ioctl access (off by default, but testers
  want to test it)"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm: allow DRM_IOCTL_VERSION on render-nodes
  drm/i915: Fix the PPT fdi lane bifurcate state handling on ivb
  drm/i915: No LVDS hardware on Intel D410PT and D425KT
  drm/i915/dp: workaround BIOS eDP bpp clamping issue
  drm/i915: Add HSW CRT output readout support
  drm/i915: Add support for pipe_bpp readout
2013-10-30 12:27:12 -07:00
Linus Torvalds 182b4fd9f3 sound fixes for 3.12-final
A few small HD-audio regression fixes, mostly for stable kernels, too.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQIcBAABAgAGBQJScOAKAAoJEGwxgFQ9KSmknI8P/18upoLMoGn+zJYkfTFPkpXY
 X59FdVi9C/7wb+LQz9geHzDI4npZyLCVp2HUfwxCw12//MtB4D/zAxEC+1eyqjyK
 V45IUyBwly54+xQQdFdT1CkDmx6sW0Q+yfy38+KJR5IDPHSXw6IJg3pNOKJu5/Gh
 YB7FjnUdy2BLaIp1FDGS6NVkDfkSZZSTGvh6e1YXXennf1fhy0AalRx2y7091OhW
 hPjBMCatPeiiaUbTeduYrC0/6NjENNjsM/C2j489R47JtYELihwm2DHV+RxVQMGC
 kPmHXGIvqTZaIgX5mIrAlUfWAojx0W7Bt8I0L768ofg8NqF5x1Nohtnsq8Vmg4jz
 K8C7g/0AIR58bD4Q2eavVEMevlpeAaF79pTwFvShProPrposE+sv/0a38u2VarxS
 fBc8DgnBtZzYbaZRG/0gHEXS2WzOkaP7IMv/0B8F5W+cOQfaJCUUWZPv86ebGIcY
 0y4q0rDfQ58Wq9p3QEr1Z7E38gusmvU1pLteWZ+3jw661uy3prOiJRX+O3XTrBk5
 6ZABBrsMLkiNqxOeNZtFu0Gjdyq4KbNV/LSMUFz0X5E+JGGqZndvl1/AJZM6pppi
 dB28rAYwXD0TF9RvEZsm9uxPKKdFk+lslfTwZP1xJQimHR0WkS6chU1DjYp+2eWL
 7ug1CEQAAFd4ZdEnp+dL
 =HqzC
 -----END PGP SIGNATURE-----

Merge tag 'sound-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound

Pull sound fixes from Takashi Iwai:
 "A few small HD-audio regression fixes, mostly for stable kernels, too"

* tag 'sound-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda - Fix silent headphone on Thinkpads with AD1984A codec
  ALSA: hda - Add missing initial vmaster hook at build_controls callback
  ALSA: hda - Fix unbalanced runtime PM refcount after S3/S4
2013-10-30 12:26:29 -07:00
Linus Torvalds 96d33b086b Fixes for the 3.12 debugfs problem---removing the duplicate directory
name, and using a better the error code.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.14 (GNU/Linux)
 
 iQIcBAABAgAGBQJScOswAAoJEBvWZb6bTYbyCO8P/RoJy4EgsEjv9Qxfr+wfHXX0
 QOz/7fqEsFFMDh1Fiyjvg9uNYj5jQO9lzQfX0ea0uc4svIMUBWaAlyQVL/U0igkp
 2DrIoRh1aNa9Lt4RDsGswapreJylGgyhADa2W9r1tlPna7dlaPCEHGxZBR112KJc
 R9t0PMIq7NBGvPGBhiOkjeDVlqWUrEQvxOQW8ZQZw2pBc54DSreY9nq3n1dIhqMp
 gxpAKi3h5YWK8lzFxFSOLKnRqC+5SAUj2Bk8g37ZESJXp7bpmn74DpuK4KiLLokP
 V3rUvHO1p0eZSx0QWuV9QrPV6Q1VVuhLEinWnCdejhXUqk/tCR5EOMKMcHIk2xad
 6ApE7a4UPs9VmXp5Ry7/k6lorOrBuvwArPwJOCpCN7zAN1gEmmfFg3KbFdtbaIgx
 g4hEtqWQ6VULBxyDXCFHYbXGLS22kgWoQCR3ToGqbjzuZmZph49NbLjlt6d7o6w0
 n+UMZqcpLA9eUhq4Yi0IAGe45pizm5rdC4xRpbH7bK7WmKywYw+zf+JSOheTLwtm
 ER0sTmcyMSP68ysnJCLgh4hYf1lxoaQ/8SEdh331VIrThmHYyWGZD4Ol9YKg5xwU
 Yzd3wedxYYIiJ1vFfZykMWUT9zLU3feMDvq2s2maqg+uV/b4uPfZhwnFLBU+PZKC
 cxkXsb/7oZ//tmGF1MEm
 =GwaF
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 "Fixes for the 3.12 debugfs problem - removing the duplicate directory
  name, and using a better the error code"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: use a more sensible error number when debugfs directory creation fails
  KVM: Fix modprobe failure for kvm_intel/kvm_amd
2013-10-30 12:25:15 -07:00
Dan Carpenter a8b33654b1 Staging: sb105x: info leak in mp_get_count()
The icount.reserved[] array isn't initialized so it leaks stack
information to userspace.

Reported-by: Nico Golde <nico@ngolde.de>
Reported-by: Fabian Yamaguchi <fabs@goesec.de>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-30 12:24:50 -07:00
Dan Carpenter 8d1e72250c Staging: bcm: info leak in ioctl
The DevInfo.u32Reserved[] array isn't initialized so it leaks kernel
information to user space.

Reported-by: Nico Golde <nico@ngolde.de>
Reported-by: Fabian Yamaguchi <fabs@goesec.de>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-30 12:24:49 -07:00
Dan Carpenter b5e2f33986 staging: wlags49_h2: buffer overflow setting station name
We need to check the length parameter before doing the memcpy().  I've
actually changed it to strlcpy() as well so that it's NUL terminated.

You need CAP_NET_ADMIN to trigger these so it's not the end of the
world.

Reported-by: Nico Golde <nico@ngolde.de>
Reported-by: Fabian Yamaguchi <fabs@goesec.de>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-30 12:24:49 -07:00
Dan Carpenter f856567b93 aacraid: missing capable() check in compat ioctl
In commit d496f94d22 ('[SCSI] aacraid: fix security weakness') we
added a check on CAP_SYS_RAWIO to the ioctl.  The compat ioctls need the
check as well.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-30 12:24:49 -07:00
Dan Carpenter c2c65cd2e1 staging: ozwpan: prevent overflow in oz_cdev_write()
We need to check "count" so we don't overflow the ei->data buffer.

Reported-by: Nico Golde <nico@ngolde.de>
Reported-by: Fabian Yamaguchi <fabs@goesec.de>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-30 12:24:49 -07:00
Dan Carpenter 201f99f170 uml: check length in exitcode_proc_write()
We don't cap the size of buffer from the user so we could write past the
end of the array here.  Only root can write to this file.

Reported-by: Nico Golde <nico@ngolde.de>
Reported-by: Fabian Yamaguchi <fabs@goesec.de>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-30 12:24:49 -07:00
Takashi Iwai c4a4ddaefb ASoC: Fixes for v3.12
A few of the Coverity fixes from Takashi, one of which (the wm_hubs one)
 is particularly noticable.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.15 (GNU/Linux)
 
 iQIcBAABAgAGBQJScUA0AAoJELSic+t+oim9Yu8P/Rve++VdhWT/NPrhRvHLhnt7
 CXaXdAKt2tS8mZCrvho/G2b22ZGJML1RseCF4ORIPYaLAnk86G6mqNldFWGiBy1D
 ainPIQKahc0Pxu9TlFuj27r6M+S/t3JXxgX9R8rJr8yz4JRVzCucrRMlrFPXXPNW
 PDu9djCf6Mv3X9M/tpnZUQo2gpkmfzWmrF6/TSb/91TT7ZhYouzC+pkydHvyvXU7
 Ah3MhNPe7rXXNZsdxn8jSPwN4g+vHgkLYg+OrrCtfOppG0XLQPzmq1xWEeqSltLi
 hiVv36VHzzCAymqn29B8kUidRlYcRQiQliv50B4zUCKj78LsEr6/bO3PLpiJkmtm
 DQTckVHT6i2teQdFsBoJ9GDZhkIphk3wVFivG47DhmAK7W1vB2pX67DF4lKrsz8w
 wSwtcUj9lPVoEK/stxTEAU+UNvIrwhbEKxwDi9F4K4eQkaf4CtmTq37cE2QR4uFY
 lxqqYU8oCUypzCEtWXZ28N2+BBCoH+Fjw9LgM0eIYrw6UgmtmhY6Az05/T9ZjagP
 PYC9I+ootacB2ApBF6E2wM+3zT7tookNCa2S3pd0kYrYXXqo0P79h2JUyfhQwCHn
 CY29c0YassHjL5lTv0rBW9lbNAZg8wFAMsguOMqXFi/msFKhcpH2aLZ5+R7mUl0s
 QPIzGI3OMMFMx6PDQ3KS
 =J0sP
 -----END PGP SIGNATURE-----

Merge tag 'asoc-fix-v3.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v3.12

A few of the Coverity fixes from Takashi, one of which (the wm_hubs one)
is particularly noticable.
2013-10-30 18:42:13 +01:00
Mark Brown 8723b795aa Merge remote-tracking branch 'asoc/fix/wm8994' into asoc-linus 2013-10-30 10:11:55 -07:00
Takashi Iwai 268ff14525 ASoC: wm_hubs: Add missing break in hp_supply_event()
Spotted by coverity CID 115170.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
Cc: stable@vger.kernel.org
2013-10-30 09:35:22 -07:00
Markos Chandras 13b7ea6377 MIPS: malta: Fix GIC interrupt offsets
The GIC interrupt offsets are calculated based on the value of NR_CPUS.
However, this is wrong because NR_CPUS may or may not contain the real
number of the actual cpus present in the system. We fix that by using
the 'nr_cpu_ids' variable which contains the real number of cpus in
the system. Previously, an MT core (eg with 8 VPEs) will fail to boot if
NR_CPUS was > 8 with the following errors:

------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at kernel/irq/chip.c:670 __irq_set_handler+0x15c/0x164()
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W    3.12.0-rc5-00087-gced5633 5
Stack : 00000006 00000004 00000000 00000000 00000000 00000000 807a4f36 00000053
          807a0000 00000000 80173218 80565aa8 00000000 00000000 00000000 0000000
          00000000 00000000 00000000 00000000 00000000 00000000 00000000 0000000
          00000000 00000000 00000000 8054fd00 8054fd94 80500514 805657a7 8016eb4
          807a0000 80500514 00000000 00000000 80565aa8 8079a5d8 80565766 8054fd0
          ...
Call Trace:
[<801098c0>] show_stack+0x64/0x7c
[<8049c6b0>] dump_stack+0x64/0x84
[<8012efc4>] warn_slowpath_common+0x84/0xb4
[<8012f00c>] warn_slowpath_null+0x18/0x24
[<80173218>] __irq_set_handler+0x15c/0x164
[<80587cf4>] arch_init_ipiirq+0x2c/0x3c
[<805880c8>] arch_init_irq+0x3c4/0x4bc
[<80588e28>] init_IRQ+0x3c/0x50
[<805847e8>] start_kernel+0x230/0x3d8

---[ end trace 4eaa2a86a8e2da26 ]---

This is now fixed and the Malta board can boot with any NR_CPUS value
which also helps supporting more processors in a single kernel binary.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6091/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-10-30 15:43:18 +01:00
Mika Westerberg ab1225901d Revert "ACPI / hotplug / PCI: Avoid doing too much for spurious notifies"
Commit 2dc4128 (ACPI / hotplug / PCI: Avoid doing too much for
spurious notifies) changed the enable_slot() to check return value of
pci_scan_slot() and if it is zero return early from the function. It
means that there were no new devices in this particular slot.

However, if a device appeared deeper in the hierarchy the code now
ignores it causing things like Thunderbolt chaining fail to recognize
new devices.

The problem with Alex Williamson's machine was solved with commit
a47d8c8 (ACPI / hotplug / PCI: Avoid parent bus rescans on spurious
device checks) and hence we should be able to restore the original
functionality that we always rescan on bus check notification.

On a device check notification we still check what acpiphp_rescan_slot()
returns and on zero bail out early.

Fixes: 2dc41281b1 (ACPI / hotplug / PCI: Avoid doing too much for spurious notifies)
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30 15:28:52 +01:00
Rafael J. Wysocki 59612d1879 Revert "select: use freezable blocking call"
This reverts commit 9745cdb36d (select: use freezable blocking call)
that triggers problems during resume from suspend to RAM on Paul Bolle's
32-bit x86 machines.  Paul says:

  Ever since I tried running (release candidates of) v3.11 on the two
  working i686s I still have lying around I ran into issues on resuming
  from suspend. Reverting 9745cdb36d (select: use freezable blocking
  call) resolves those issues.

  Resuming from suspend on i686 on (release candidates of) v3.11 and
  later triggers issues like:

  traps: systemd[1] general protection ip:b738e490 sp:bf882fc0 error:0 in libc-2.16.so[b731c000+1b0000]

  and

  traps: rtkit-daemon[552] general protection ip:804d6e5 sp:b6cb32f0 error:0 in rtkit-daemon[8048000+d000]

  Once I hit the systemd error I can only get out of the mess that the
  system is at that point by power cycling it.

Since we are reverting another freezer-related change causing similar
problems to happen, this one should be reverted as well.

References: https://lkml.org/lkml/2013/10/29/583
Reported-by: Paul Bolle <pebolle@tiscali.nl>
Fixes: 9745cdb36d (select: use freezable blocking call)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 3.11+ <stable@vger.kernel.org> # 3.11+
2013-10-30 15:28:35 +01:00
Rafael J. Wysocki c511851de1 Revert "epoll: use freezable blocking call"
This reverts commit 1c441e9212 (epoll: use freezable blocking call)
which is reported to cause user space memory corruption to happen
after suspend to RAM.

Since it appears to be extremely difficult to root cause this
problem, it is best to revert the offending commit and try to address
the original issue in a better way later.

References: https://bugzilla.kernel.org/show_bug.cgi?id=61781
Reported-by: Natrio <natrio@list.ru>
Reported-by: Jeff Pohlmeyer <yetanothergeek@gmail.com>
Bisected-by: Leo Wolf <jclw@ymail.com>
Fixes: 1c441e9212 (epoll: use freezable blocking call)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 3.11+ <stable@vger.kernel.org> # 3.11+
2013-10-30 15:27:53 +01:00
Takashi Iwai 6fc16e58ad ALSA: hda - Add a fixup for ASUS N76VZ
ASUS N76VZ needs the same fixup as N56VZ for supporting the boost
speaker.

Bugzilla: https://bugzilla.novell.com/show_bug.cgi?id=846529
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-10-30 12:31:35 +01:00
Paolo Bonzini 0c8eb04a62 KVM: use a more sensible error number when debugfs directory creation fails
I don't know if this was due to cut and paste, or somebody was really
using a D20 to pick the error code for kvm_init_debugfs as suggested by
Linus (EFAULT is 14, so the possibility cannot be entirely ruled out).

In any case, this patch fixes it.

Reported-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30 12:15:34 +01:00
Tim Gardner d780a31271 KVM: Fix modprobe failure for kvm_intel/kvm_amd
The x86 specific kvm init creates a new conflicting
debugfs directory which causes modprobe issues
with kvm_intel and kvm_amd. For example,

sudo modprobe kvm_amd
modprobe: ERROR: could not insert 'kvm_amd': Bad address

The simplest fix is to just rename the directory. The following
KVM config options are set:

CONFIG_KVM_GUEST=y
CONFIG_KVM_DEBUG_FS=y
CONFIG_HAVE_KVM=y
CONFIG_HAVE_KVM_IRQCHIP=y
CONFIG_HAVE_KVM_IRQ_ROUTING=y
CONFIG_HAVE_KVM_EVENTFD=y
CONFIG_KVM_APIC_ARCHITECTURE=y
CONFIG_KVM_MMIO=y
CONFIG_KVM_ASYNC_PF=y
CONFIG_HAVE_KVM_MSI=y
CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT=y
CONFIG_KVM=m
CONFIG_KVM_INTEL=m
CONFIG_KVM_AMD=m
CONFIG_KVM_DEVICE_ASSIGNMENT=y

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
[Change debugfs directory name. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30 12:10:42 +01:00
David Herrmann 3d3b78c06c drm: allow DRM_IOCTL_VERSION on render-nodes
DRM_IOCTL_VERSION is a reliable way to get the driver-name and version
information. It's not related to the interface-version (SET_VERSION ioctl)
so we can safely enable it on render-nodes.

Note that gbm uses udev-BUSID to load the correct mesa driver. However,
the VERSION ioctl should be the more reliable way to do this (in case we
add new DRM-bus drivers which have no BUSID or similar).

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-10-30 14:41:56 +10:00
Dave Airlie 2f2632ff6e Merge tag 'drm-intel-fixes-2013-10-29' of git://people.freedesktop.org/~danvet/drm-intel into drm-fixes
Regression and warn fixes for i915.

* tag 'drm-intel-fixes-2013-10-29' of git://people.freedesktop.org/~danvet/drm-intel:
  drm/i915: Fix the PPT fdi lane bifurcate state handling on ivb
  drm/i915: No LVDS hardware on Intel D410PT and D425KT
  drm/i915/dp: workaround BIOS eDP bpp clamping issue
  drm/i915: Add HSW CRT output readout support
  drm/i915: Add support for pipe_bpp readout
2013-10-30 12:30:12 +10:00
Deng-Cheng Zhu 7f081f1755 MIPS: Perf: Fix 74K cache map
According to Software User's Manual, the event of last-level-cache
read/write misses is mapped to even counters. Odd counters of that
event number count miss cycles.

Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6036/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-10-29 21:18:23 +01:00
Linus Torvalds 7314e613d5 Fix a few incorrectly checked [io_]remap_pfn_range() calls
Nico Golde reports a few straggling uses of [io_]remap_pfn_range() that
really should use the vm_iomap_memory() helper.  This trivially converts
two of them to the helper, and comments about why the third one really
needs to continue to use remap_pfn_range(), and adds the missing size
check.

Reported-by: Nico Golde <nico@ngolde.de>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org.
2013-10-29 10:21:34 -07:00
Linus Torvalds f9ec2e6f79 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf tooling fixes from Ingo Molnar:
 "This contains five tooling fixes:

   - fix a remaining mmap2 assumption which resulted in perf top output
     breakage
   - fix mmap ring-buffer processing bug that corrupts data
   - fix for a severe python scripting memory leak
   - fix broken (and user-visible) -g option handling
   - fix stdio output

  The diffstat size is larger than what we'd like to see this late :-/"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf tools: Fixup mmap event consumption
  perf top: Split -G and --call-graph
  perf record: Split -g and --call-graph
  perf hists: Add color overhead for stdio output buffer
  perf tools: Fix up /proc/PID/maps parsing
  perf script python: Fix mem leak due to missing Py_DECREFs on dict entries
2013-10-29 08:36:50 -07:00
Linus Torvalds 2a999aa0a1 Kconfig: make KOBJECT_RELEASE debugging require timer debugging
Without the timer debugging, the delayed kobject release will just
result in undebuggable oopses if it triggers any latent bugs.  That
doesn't actually help debugging at all.

So make DEBUG_KOBJECT_RELEASE depend on DEBUG_OBJECTS_TIMERS to avoid
having people enable one without the other.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-29 08:33:36 -07:00
Daniel Vetter 1fbc0d789d drm/i915: Fix the PPT fdi lane bifurcate state handling on ivb
Originally I've thought that this is leftover hw state dirt from the
BIOS. But after way too much helpless flailing around on my part I've
noticed that the actual bug is when we change the state of an already
active pipe.

For example when we change the fdi lines from 2 to 3 without switching
off outputs in-between we'll never see the crucial on->off transition
in the ->modeset_global_resources hook the current logic relies on.

Patch version 2 got this right by instead also checking whether the
pipe is indeed active. But that in turn broke things when pipes have
been turned off through dpms since the bifurcate enabling is done in
the ->crtc_mode_set callback.

To address this issues discussed with Ville in the patch review move
the setting of the bifurcate bit into the ->crtc_enable hook. That way
we won't wreak havoc with this state when userspace puts all other
outputs into dpms off state. This also moves us forward with our
overall goal to unify the modeset and dpms on paths (which we need to
have to allow runtime pm in the dpms off state).

Unfortunately this requires us to move the bifurcate helpers around a
bit.

Also update the commit message, I've misanalyzed the bug rather badly.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=70507
Tested-by: Jan-Michael Brummer <jan.brummer@tabos.org>
Cc: stable@vger.kernel.org
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-10-29 13:52:56 +01:00
Ben Segall f9f9ffc237 sched: Avoid throttle_cfs_rq() racing with period_timer stopping
throttle_cfs_rq() doesn't check to make sure that period_timer is running,
and while update_curr/assign_cfs_runtime does, a concurrently running
period_timer on another cpu could cancel itself between this cpu's
update_curr and throttle_cfs_rq(). If there are no other cfs_rqs running
in the tg to restart the timer, this causes the cfs_rq to be stranded
forever.

Fix this by calling __start_cfs_bandwidth() in throttle if the timer is
inactive.

(Also add some sched_debug lines for cfs_bandwidth.)

Tested: make a run/sleep task in a cgroup, loop switching the cgroup
between 1ms/100ms quota and unlimited, checking for timer_active=0 and
throttled=1 as a failure. With the throttle_cfs_rq() change commented out
this fails, with the full patch it passes.

Signed-off-by: Ben Segall <bsegall@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: pjt@google.com
Link: http://lkml.kernel.org/r/20131016181632.22647.84174.stgit@sword-of-the-dawn.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 12:02:32 +01:00
Paul Turner 0ac9b1c218 sched: Guarantee new group-entities always have weight
Currently, group entity load-weights are initialized to zero. This
admits some races with respect to the first time they are re-weighted in
earlty use. ( Let g[x] denote the se for "g" on cpu "x". )

Suppose that we have root->a and that a enters a throttled state,
immediately followed by a[0]->t1 (the only task running on cpu[0])
blocking:

  put_prev_task(group_cfs_rq(a[0]), t1)
  put_prev_entity(..., t1)
  check_cfs_rq_runtime(group_cfs_rq(a[0]))
  throttle_cfs_rq(group_cfs_rq(a[0]))

Then, before unthrottling occurs, let a[0]->b[0]->t2 wake for the first
time:

  enqueue_task_fair(rq[0], t2)
  enqueue_entity(group_cfs_rq(b[0]), t2)
  enqueue_entity_load_avg(group_cfs_rq(b[0]), t2)
  account_entity_enqueue(group_cfs_ra(b[0]), t2)
  update_cfs_shares(group_cfs_rq(b[0]))
  < skipped because b is part of a throttled hierarchy >
  enqueue_entity(group_cfs_rq(a[0]), b[0])
  ...

We now have b[0] enqueued, yet group_cfs_rq(a[0])->load.weight == 0
which violates invariants in several code-paths. Eliminate the
possibility of this by initializing group entity weight.

Signed-off-by: Paul Turner <pjt@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131016181627.22647.47543.stgit@sword-of-the-dawn.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 12:02:23 +01:00
Ben Segall 927b54fccb sched: Fix hrtimer_cancel()/rq->lock deadlock
__start_cfs_bandwidth calls hrtimer_cancel while holding rq->lock,
waiting for the hrtimer to finish. However, if sched_cfs_period_timer
runs for another loop iteration, the hrtimer can attempt to take
rq->lock, resulting in deadlock.

Fix this by ensuring that cfs_b->timer_active is cleared only if the
_latest_ call to do_sched_cfs_period_timer is returning as idle. Then
__start_cfs_bandwidth can just call hrtimer_try_to_cancel and wait for
that to succeed or timer_active == 1.

Signed-off-by: Ben Segall <bsegall@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: pjt@google.com
Link: http://lkml.kernel.org/r/20131016181622.22647.16643.stgit@sword-of-the-dawn.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 12:02:21 +01:00
Ben Segall db06e78cc1 sched: Fix cfs_bandwidth misuse of hrtimer_expires_remaining
hrtimer_expires_remaining does not take internal hrtimer locks and thus
must be guarded against concurrent __hrtimer_start_range_ns (but
returning HRTIMER_RESTART is safe). Use cfs_b->lock to make it safe.

Signed-off-by: Ben Segall <bsegall@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: pjt@google.com
Link: http://lkml.kernel.org/r/20131016181617.22647.73829.stgit@sword-of-the-dawn.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 12:02:20 +01:00
Ben Segall 1ee14e6c8c sched: Fix race on toggling cfs_bandwidth_used
When we transition cfs_bandwidth_used to false, any currently
throttled groups will incorrectly return false from cfs_rq_throttled.
While tg_set_cfs_bandwidth will unthrottle them eventually, currently
running code (including at least dequeue_task_fair and
distribute_cfs_runtime) will cause errors.

Fix this by turning off cfs_bandwidth_used only after unthrottling all
cfs_rqs.

Tested: toggle bandwidth back and forth on a loaded cgroup. Caused
crashes in minutes without the patch, hasn't crashed with it.

Signed-off-by: Ben Segall <bsegall@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: pjt@google.com
Link: http://lkml.kernel.org/r/20131016181611.22647.80365.stgit@sword-of-the-dawn.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 12:02:19 +01:00
Peter Zijlstra e8a923cc1f perf/x86: Fix NMI measurements
OK, so what I'm actually seeing on my WSM is that sched/clock.c is
'broken' for the purpose we're using it for.

What triggered it is that my WSM-EP is broken :-(

  [    0.001000] tsc: Fast TSC calibration using PIT
  [    0.002000] tsc: Detected 2533.715 MHz processor
  [    0.500180] TSC synchronization [CPU#0 -> CPU#6]:
  [    0.505197] Measured 3 cycles TSC warp between CPUs, turning off TSC clock.
  [    0.004000] tsc: Marking TSC unstable due to check_tsc_sync_source failed

For some reason it consistently detects TSC skew, even though NHM+
should have a single clock domain for 'reasonable' systems.

This marks sched_clock_stable=0, which means that we do fancy stuff to
try and get a 'sane' clock. Part of this fancy stuff relies on the tick,
clearly that's gone when NOHZ=y. So for idle cpus time gets stuck, until
it either wakes up or gets kicked by another cpu.

While this is perfectly fine for the scheduler -- it only cares about
actually running stuff, and when we're running stuff we're obviously not
idle. This does somewhat break down for perf which can trigger events
just fine on an otherwise idle cpu.

So I've got NMIs get get 'measured' as taking ~1ms, which actually
don't last nearly that long:

          <idle>-0     [013] d.h.   886.311970: rcu_nmi_enter <-do_nmi
  ...
          <idle>-0     [013] d.h.   886.311997: perf_sample_event_took: HERE!!! : 1040990

So ftrace (which uses sched_clock(), not the fancy bits) only sees
~27us, but we measure ~1ms !!

Now since all this measurement stuff lives in x86 code, we can actually
fix it.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: mingo@kernel.org
Cc: dave.hansen@linux.intel.com
Cc: eranian@google.com
Cc: Don Zickus <dzickus@redhat.com>
Cc: jmario@redhat.com
Cc: acme@infradead.org
Link: http://lkml.kernel.org/r/20131017133350.GG3364@laptop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 12:01:20 +01:00
Peter Zijlstra bf378d341e perf: Fix perf ring buffer memory ordering
The PPC64 people noticed a missing memory barrier and crufty old
comments in the perf ring buffer code. So update all the comments and
add the missing barrier.

When the architecture implements local_t using atomic_long_t there
will be double barriers issued; but short of introducing more
conditional barrier primitives this is the best we can do.

Reported-by: Victor Kaplansky <victork@il.ibm.com>
Tested-by: Victor Kaplansky <victork@il.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: michael@ellerman.id.au
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: anton@samba.org
Cc: benh@kernel.crashing.org
Link: http://lkml.kernel.org/r/20131025173749.GG19466@laptop.lan
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 12:01:19 +01:00
Mel Gorman 0255d49184 mm: Account for a THP NUMA hinting update as one PTE update
A THP PMD update is accounted for as 512 pages updated in vmstat.  This is
large difference when estimating the cost of automatic NUMA balancing and
can be misleading when comparing results that had collapsed versus split
THP. This patch addresses the accounting issue.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-10-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 11:38:17 +01:00
Mel Gorman 3f926ab945 mm: Close races between THP migration and PMD numa clearing
THP migration uses the page lock to guard against parallel allocations
but there are cases like this still open

  Task A					Task B
  ---------------------				---------------------
  do_huge_pmd_numa_page				do_huge_pmd_numa_page
  lock_page
  mpol_misplaced == -1
  unlock_page
  goto clear_pmdnuma
						lock_page
						mpol_misplaced == 2
						migrate_misplaced_transhuge
  pmd = pmd_mknonnuma
  set_pmd_at

During hours of testing, one crashed with weird errors and while I have
no direct evidence, I suspect something like the race above happened.
This patch extends the page lock to being held until the pmd_numa is
cleared to prevent migration starting in parallel while the pmd_numa is
being cleared. It also flushes the old pmd entry and orders pagetable
insertion before rmap insertion.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-9-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 11:38:05 +01:00
Mel Gorman c61109e34f mm: numa: Sanitize task_numa_fault() callsites
There are three callers of task_numa_fault():

 - do_huge_pmd_numa_page():
     Accounts against the current node, not the node where the
     page resides, unless we migrated, in which case it accounts
     against the node we migrated to.

 - do_numa_page():
     Accounts against the current node, not the node where the
     page resides, unless we migrated, in which case it accounts
     against the node we migrated to.

 - do_pmd_numa_page():
     Accounts not at all when the page isn't migrated, otherwise
     accounts against the node we migrated towards.

This seems wrong to me; all three sites should have the same
sementaics, furthermore we should accounts against where the page
really is, we already know where the task is.

So modify all three sites to always account; we did after all receive
the fault; and always account to where the page is after migration,
regardless of success.

They all still differ on when they clear the PTE/PMD; ideally that
would get sorted too.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-8-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 11:37:52 +01:00
Mel Gorman 587fe586f4 mm: Prevent parallel splits during THP migration
THP migrations are serialised by the page lock but on its own that does
not prevent THP splits. If the page is split during THP migration then
the pmd_same checks will prevent page table corruption but the unlock page
and other fix-ups potentially will cause corruption. This patch takes the
anon_vma lock to prevent parallel splits during migration.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-7-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 11:37:39 +01:00
Mel Gorman 42836f5f8b mm: Wait for THP migrations to complete during NUMA hinting faults
The locking for migrating THP is unusual. While normal page migration
prevents parallel accesses using a migration PTE, THP migration relies on
a combination of the page_table_lock, the page lock and the existance of
the NUMA hinting PTE to guarantee safety but there is a bug in the scheme.

If a THP page is currently being migrated and another thread traps a
fault on the same page it checks if the page is misplaced. If it is not,
then pmd_numa is cleared. The problem is that it checks if the page is
misplaced without holding the page lock meaning that the racing thread
can be migrating the THP when the second thread clears the NUMA bit
and faults a stale page.

This patch checks if the page is potentially being migrated and stalls
using the lock_page if it is potentially being migrated before checking
if the page is misplaced or not.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-6-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 11:37:19 +01:00
Mel Gorman 1dd49bfa34 mm: numa: Do not account for a hinting fault if we raced
If another task handled a hinting fault in parallel then do not double
account for it.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-5-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 11:37:05 +01:00
Ingo Molnar cd65718712 perf/urgent fixes:
. Add color overhead for stdio output buffer, which fixes
   --stdio output being chopped up on the hot (red) entries,
   fix from Jiri Olsa.
 
 . Get 'perf record -g -a sleep 1' working again, removing the
   need for -- separating perf options from the workload, restoring
   ages old behaviour, fix from Jiri Olsa.
   More patches allowing ~/.perfconfig setting up of default
   callchain collecting method ("fp" or "dwarf") left for next
   merge window.
 
 . Fixup mmap event consumption, where we were acking the
   consumption by writing the tail before actually accessing
   the event, which could lead to using overwritten records
   in things like 'perf record --call-graph'.  from Zhouyi Zhou.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.14 (GNU/Linux)
 
 iQIcBAABAgAGBQJSbrexAAoJENZQFvNTUqpA+MIP/1dMAat/+jAobBvy9s69rJbT
 OV2QxqS5haA6rjbyogY7AiaCM/bSFO9dpLDF31NUTc3s6hiMsHnXnogQxvGGrBzT
 lzj45V9/a8XXl8Wxbpv0z4mI7ppNR3KjJdkBTsuqso5GivzMuG/8/N7ZxYB8kSlL
 vnWLRBKiBa/sDKIhKy5oEqmMMa+kPmwIXGZiKFxWkNMjmBtK80SB7MtPernhLNGf
 wj6EEulphPR1s8VHXqZIoijEvgw2vEXDTFapKd53EV+UPCII13NW7gicgPXyiWrY
 BIRW4Pwl98y9qHEc5gSq5Eotcl9JhIPQVegTSnvx8jJ7x0bYrxmChb/I9eAjWQcj
 YQAKGqUoQGu0PJv8TeIoGsxNMFxeeeMKzf275KKc5g6Les6gIHYKOmW7RPXHIIA7
 DHGYOJ808jMrNFmAkKNmxQGbE7forMFj6CPDgGpGezqTUbGsszpzga2QQgI0QmrY
 l8aPUsirF5cZ67vPk7dnUt58FayfKMdGME2dkU352hjOL1V5EeVdxx46zZsPQNyQ
 evQvkGBmRm6WFi6Sybjc6i4Gkn9F1O5sNDtEDbSQ6aZH5tNnktzLoufPrWwHKV95
 GzEHpCuAeZbagPF6WSxpNTb2xfScPb6PfveGm0gbypwl/KaAr47w8VCWJiuvpSOv
 yV83qEooKW0LUn4JXrH3
 =U+a8
 -----END PGP SIGNATURE-----

Merge tag 'perf-urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

 * Add color overhead for stdio output buffer, which fixes
   --stdio output being chopped up on the hot (red) entries,
   fix from Jiri Olsa.

 * Get 'perf record -g -a sleep 1' working again, removing the
   need for -- separating perf options from the workload, restoring
   ages old behaviour, fix from Jiri Olsa.
   More patches allowing ~/.perfconfig setting up of default
   callchain collecting method ("fp" or "dwarf") left for next
   merge window.

 * Fixup mmap event consumption, where we were acking the
   consumption by writing the tail before actually accessing
   the event, which could lead to using overwritten records
   in things like 'perf record --call-graph'. From Zhouyi Zhou.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-10-29 09:06:07 +01:00
Linus Torvalds c9ca72fc56 Xtensa patchset for v3.12-rc6
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.12 (GNU/Linux)
 
 iQIcBAABAgAGBQJSXuCxAAoJEI9vqH3mFV2sdWwP/11xVQFtzoT01k9P4fZeFCMT
 +dGztMBY6bODMEyeC9raX6sJhuOYNivS2IBFJ4qv9p+kcCplYE0EsB3MfOQ60NdV
 eV2DdnHrPKgIPUutGf7mcZ5bXB8q8HEuEFn0ONsCdNTAxzrcLxaPZU3MeGhSfL0H
 d/RPPmSW8+vLEMWUe58EB2J8Z1DJye4O0pbxskjGA64KrLssKBG3LWBQBdTsihkE
 r2olYYT0j7osJ7loLbyll/CcacQTfJbQT8Xd0Y7MbLYR/G6EVMwb6PkzkFnUPMIQ
 zLwMAOgL8/E250p4ab0Wy8vf9rW+938qR93oZEyO8TRDdF/mYNQb+GK+ZKUrMrxg
 eZ/pOhKQ+xUKtt23xrvbXR3nTnI9AfiJ1nhuO4UmX5WIhyJXDcYYk+rujlEduxGm
 IJ7p5cRWBdqC+iIiSzQJjyW4drIXU6QJ+ureOGo0vBcBJsLRbUFYLt+08Rb60/d1
 zgS8L7DpKRUZlIrbD6/HxyUimJCTGERsvTSDZYCYs1+ri/YKV4a8Ukfsl8bWLbhd
 Le5PyMeusWaM6MHCIOJPys2SpsKGl9UCaVr7Nz1Lr6HIqZJUN61rNVSIcUpufiqt
 hPSYtljmz6746Z6QvNW0OD8+qE5foplCnv94Oqj9tb24gHfINPXkjiaEKhPDICi0
 6cCQj4pCsjjlzXXmn5Fp
 =sopZ
 -----END PGP SIGNATURE-----

Merge tag 'xtensa-next-20131015' of git://github.com/czankel/xtensa-linux

Pull Xtensa patchset from Chris Zankel:
 "The main patch fixes a bug that can cause a kernel panic, and was
  introduced in rc1.  The other two have been discovered by a uclibc
  test and 'coccinelle'"

* tag 'xtensa-next-20131015' of git://github.com/czankel/xtensa-linux:
  xtensa: Cocci spatch "noderef"
  xtensa: don't use alternate signal stack on threads
  xtensa: fix fast_syscall_spill_registers_fixup
2013-10-28 16:58:05 -07:00
Linus Torvalds 5d914a959d SCSI fixes on 20131028
This is a set of four patches that revert functionality introduced in the
 merge window to sg.  The locking changes turned out to introduce this bug:
 
     [  205.372901] [ BUG: lock held when returning to user space! ]
 [...]
     [  205.373285]  #0:  (&sdp->o_sem){.+.+..}, at: [<ffffffff8161e650>] sg_open+0x3a0/0x4d0
 
 The fix is large, so at this late stage we'd like to revert the functionality
 and start again in the next merge window.
 
 Signed-off-by: James Bottomley <JBottomley@Parallels.com>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.19 (GNU/Linux)
 
 iQEcBAABAgAGBQJSbneXAAoJEDeqqVYsXL0Mr+AIAJRkPeIzyX59Y16nAlxY8tZj
 MCYFZ9v9TiVEXm2+AM/Z/Y6jVYG3wgkRzZARyOxeNeRsyWFMsm74WQG5AIopwL5B
 liN9tMlcxl3Ofdh9Ww1Os7AaIhm3xmiRTNsNirNxgh5Y3+XH8MMTv5QR97XIt5Ys
 arDJUAJKtYJIcgMbYpDdQ7vb8deNsrwC0mQ2vbdox6tMKn8wIigsyZKI/+55imJP
 uPZjruhFQxhzMzi5+kR8q/Y2hj+2Lo0pSIEWjO2K/xqLzMI/8IkCwx5gYnNdxONE
 Rrj/6VevFd0w3G9EWb8d4HhptyTMFkq4D8XoSxepSFdA1Ti4kVixwXw+PRdEU/I=
 =pSy2
 -----END PGP SIGNATURE-----

Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "This is a set of four patches that revert functionality introduced in
  the merge window to sg.  The locking changes turned out to introduce
  this bug:

      [  205.372901] [ BUG: lock held when returning to user space! ]
   [...]
      [  205.373285]  #0:  (&sdp->o_sem){.+.+..}, at: [<ffffffff8161e650>] sg_open+0x3a0/0x4d0

  The fix is large, so at this late stage we'd like to revert the
  functionality and start again in the next merge window"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  [SCSI] Revert "sg: use rwsem to solve race during exclusive open"
  [SCSI] Revert "sg: no need sg_open_exclusive_lock"
  [SCSI] Revert "sg: checking sdp->detached isn't protected when open"
  [SCSI] Revert "sg: push file descriptor list locking down to per-device locking"
2013-10-28 16:57:13 -07:00
Zhouyi Zhou 8e50d384cc perf tools: Fixup mmap event consumption
The tail position of the event buffer should only be modified after
actually use that event.

If not the event buffer could be invalid before use, and segment fault
occurs when invoking perf top -G.

Signed-off-by: Zhouyi Zhou <yizhouzhou@ict.ac.cn>
Cc: David Ahern <dsahern@gmail.com>
Cc: Zhouyi Zhou <yizhouzhou@ict.ac.cn>
Link: http://lkml.kernel.org/r/1382600613-32177-1-git-send-email-zhouzhouyi@gmail.com
[ Simplified the logic using exit gotos and renamed write_tail method to mmap_consume ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-10-28 16:06:00 -03:00
Jiri Olsa ae779a6309 perf top: Split -G and --call-graph
Splitting -G and --call-graph for record command, so we could use '-G'
with no option.

The '-G' option now takes NO argument and enables the configured unwind
method, which is currently the frame pointers method.

It will be possible to configure unwind method via config file in
upcoming patches.

All current '-G' arguments is overtaken by --call-graph option.

NOTE: The documentation for top --call-graph option
      was wrongly copied from report command.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: David Ahern <dsahern@gmail.com>
Tested-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: David Ahern <dsahern@gmail.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1382797536-32303-3-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-10-28 16:06:00 -03:00