linux-stable.git, branch v4.3.3

Linux 4.3.3

2015-12-15T05:41:43+00:00

Btrfs: fix regression running delayed references when using qgroups

2015-12-15T05:41:09+00:00

commit b06c4bf5c874a57254b197f53ddf588e7a24a2bf upstream.

In the kernel 4.2 merge window we had a big changes to the implementation
of delayed references and qgroups which made the no_quota field of delayed
references not used anymore. More specifically the no_quota field is not
used anymore as of:

  commit 0ed4792af0e8 ("btrfs: qgroup: Switch to new extent-oriented qgroup mechanism.")

Leaving the no_quota field actually prevents delayed references from
getting merged, which in turn cause the following BUG_ON(), at
fs/btrfs/extent-tree.c, to be hit when qgroups are enabled:

  static int run_delayed_tree_ref(...)
  {
     (...)
     BUG_ON(node->ref_mod != 1);
     (...)
  }

This happens on a scenario like the following:

  1) Ref1 bytenr X, action = BTRFS_ADD_DELAYED_REF, no_quota = 1, added.

  2) Ref2 bytenr X, action = BTRFS_DROP_DELAYED_REF, no_quota = 0, added.
     It's not merged with Ref1 because Ref1->no_quota != Ref2->no_quota.

  3) Ref3 bytenr X, action = BTRFS_ADD_DELAYED_REF, no_quota = 1, added.
     It's not merged with the reference at the tail of the list of refs
     for bytenr X because the reference at the tail, Ref2 is incompatible
     due to Ref2->no_quota != Ref3->no_quota.

  4) Ref4 bytenr X, action = BTRFS_DROP_DELAYED_REF, no_quota = 0, added.
     It's not merged with the reference at the tail of the list of refs
     for bytenr X because the reference at the tail, Ref3 is incompatible
     due to Ref3->no_quota != Ref4->no_quota.

  5) We run delayed references, trigger merging of delayed references,
     through __btrfs_run_delayed_refs() -> btrfs_merge_delayed_refs().

  6) Ref1 and Ref3 are merged as Ref1->no_quota = Ref3->no_quota and
     all other conditions are satisfied too. So Ref1 gets a ref_mod
     value of 2.

  7) Ref2 and Ref4 are merged as Ref2->no_quota = Ref4->no_quota and
     all other conditions are satisfied too. So Ref2 gets a ref_mod
     value of 2.

  8) Ref1 and Ref2 aren't merged, because they have different values
     for their no_quota field.

  9) Delayed reference Ref1 is picked for running (select_delayed_ref()
     always prefers references with an action == BTRFS_ADD_DELAYED_REF).
     So run_delayed_tree_ref() is called for Ref1 which triggers the
     BUG_ON because Ref1->red_mod != 1 (equals 2).

So fix this by removing the no_quota field, as it's not used anymore as
of commit 0ed4792af0e8 ("btrfs: qgroup: Switch to new extent-oriented
qgroup mechanism.").

The use of no_quota was also buggy in at least two places:

1) At delayed-refs.c:btrfs_add_delayed_tree_ref() - we were setting
   no_quota to 0 instead of 1 when the following condition was true:
   is_fstree(ref_root) || !fs_info->quota_enabled

2) At extent-tree.c:__btrfs_inc_extent_ref() - we were attempting to
   reset a node's no_quota when the condition "!is_fstree(root_objectid)
   || !root->fs_info->quota_enabled" was true but we did it only in
   an unused local stack variable, that is, we never reset the no_quota
   value in the node itself.

This fixes the remainder of problems several people have been having when
running delayed references, mostly while a balance is running in parallel,
on a 4.2+ kernel.

Very special thanks to Stéphane Lesimple for helping debugging this issue
and testing this fix on his multi terabyte filesystem (which took more
than one day to balance alone, plus fsck, etc).

Also, this fixes deadlock issue when using the clone ioctl with qgroups
enabled, as reported by Elias Probst in the mailing list. The deadlock
happens because after calling btrfs_insert_empty_item we have our path
holding a write lock on a leaf of the fs/subvol tree and then before
releasing the path we called check_ref() which did backref walking, when
qgroups are enabled, and tried to read lock the same leaf. The trace for
this case is the following:

  INFO: task systemd-nspawn:6095 blocked for more than 120 seconds.
  (...)
  Call Trace:
    [] schedule+0x74/0x83
    [] btrfs_tree_read_lock+0xc0/0xea
    [] ? wait_woken+0x74/0x74
    [] btrfs_search_old_slot+0x51a/0x810
    [] btrfs_next_old_leaf+0xdf/0x3ce
    [] ? ulist_add_merge+0x1b/0x127
    [] __resolve_indirect_refs+0x62a/0x667
    [] ? btrfs_clear_lock_blocking_rw+0x78/0xbe
    [] find_parent_nodes+0xaf3/0xfc6
    [] __btrfs_find_all_roots+0x92/0xf0
    [] btrfs_find_all_roots+0x45/0x65
    [] ? btrfs_get_tree_mod_seq+0x2b/0x88
    [] check_ref+0x64/0xc4
    [] btrfs_clone+0x66e/0xb5d
    [] btrfs_ioctl_clone+0x48f/0x5bb
    [] ? native_sched_clock+0x28/0x77
    [] btrfs_ioctl+0xabc/0x25cb
  (...)

The problem goes away by eleminating check_ref(), which no longer is
needed as its purpose was to get a value for the no_quota field of
a delayed reference (this patch removes the no_quota field as mentioned
earlier).

Reported-by: Stéphane Lesimple 
Tested-by: Stéphane Lesimple 
Reported-by: Elias Probst 
Reported-by: Peter Becker 
Reported-by: Malte Schröder 
Reported-by: Derek Dongray 
Reported-by: Erkki Seppala 
Cc: stable@vger.kernel.org  # 4.2+
Signed-off-by: Filipe Manana 
Reviewed-by: Qu Wenruo

cobalt: fix Kconfig dependency

2015-12-15T05:41:09+00:00

commit fc88dd16a0e430f57458e6bd9b62a631c6ea53a1 upstream.

The cobalt driver should depend on VIDEO_V4L2_SUBDEV_API.

This fixes this kbuild error:

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   99bc7215bc60f6cd414cf1b85cd9d52cc596cccb
commit: 85756a069c55e0315ac5990806899cfb607b987f [media] cobalt: add new driver
config: x86_64-randconfig-s0-09201514 (attached as .config)
reproduce:
  git checkout 85756a069c55e0315ac5990806899cfb607b987f
  # save the attached .config to linux build tree
  make ARCH=x86_64

All error/warnings (new ones prefixed by >>):

   drivers/media/i2c/adv7604.c: In function 'adv76xx_get_format':
>> drivers/media/i2c/adv7604.c:1853:9: error: implicit declaration of function 'v4l2_subdev_get_try_format' [-Werror=implicit-function-declaration]
      fmt = v4l2_subdev_get_try_format(sd, cfg, format->pad);
            ^
   drivers/media/i2c/adv7604.c:1853:7: warning: assignment makes pointer from integer without a cast [-Wint-conversion]
      fmt = v4l2_subdev_get_try_format(sd, cfg, format->pad);
          ^
   drivers/media/i2c/adv7604.c: In function 'adv76xx_set_format':
   drivers/media/i2c/adv7604.c:1882:7: warning: assignment makes pointer from integer without a cast [-Wint-conversion]
      fmt = v4l2_subdev_get_try_format(sd, cfg, format->pad);
          ^
   cc1: some warnings being treated as errors

Signed-off-by: Hans Verkuil 
Signed-off-by: Mauro Carvalho Chehab 
Signed-off-by: Greg Kroah-Hartman

ALSA: hda/hdmi - apply Skylake fix-ups to Broxton display codec

2015-12-15T05:41:09+00:00

commit e2656412f2a7343ecfd13eb74bac0a6e6e9c5aad upstream.

Broxton and Skylake have the same behavior on display audio. So this patch
applys Skylake fix-ups to Broxton.

Signed-off-by: Lu, Han 
Signed-off-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman

ALSA: pci: depend on ZONE_DMA

2015-12-15T05:41:09+00:00

commit 2db1a57986d37653583e67ccbf13082aadc8f25d upstream.

There are several sound drivers that 'select ZONE_DMA'.  This is
backwards as ZONE_DMA is an architecture capability exported to drivers.
Switch the polarity of the dependency to disable these drivers when the
architecture does not support ZONE_DMA.  This was discovered in the
context of testing/enabling devm_memremap_pages() which depends on
ZONE_DEVICE.  ZONE_DEVICE in turn depends on !ZONE_DMA.

Reported-by: Jeff Moyer 
Signed-off-by: Dan Williams 
Signed-off-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman

ceph: fix message length computation

2015-12-15T05:41:09+00:00

commit 777d738a5e58ba3b6f3932ab1543ce93703f4873 upstream.

create_request_message() computes the maximum length of a message,
but uses the wrong type for the time stamp: sizeof(struct timespec)
may be 8 or 16 depending on the architecture, while sizeof(struct
ceph_timespec) is always 8, and that is what gets put into the
message.

Found while auditing the uses of timespec for y2038 problems.

Fixes: b8e69066d8af ("ceph: include time stamp in every MDS request")
Signed-off-by: Arnd Bergmann 
Signed-off-by: Yan, Zheng 
Signed-off-by: Greg Kroah-Hartman

block: fix segment split

2015-12-15T05:41:09+00:00

commit 578270bfbd2803dc7b0b03fbc2ac119efbc73195 upstream.

Inside blk_bio_segment_split(), previous bvec pointer(bvprvp)
always points to the iterator local variable, which is obviously
wrong, so fix it by pointing to the local variable of 'bvprv'.

Fixes: 5014c311baa2b(block: fix bogus compiler warnings in blk-merge.c)
Reported-by: Michael Ellerman 
Reported-by: Mark Salter 
Tested-by: Laurent Dufour 
Tested-by: Mark Salter 
Signed-off-by: Ming Lei 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

ocfs2: fix umask ignored issue

2015-12-15T05:41:09+00:00

commit 8f1eb48758aacf6c1ffce18179295adbf3bd7640 upstream.

New created file's mode is not masked with umask, and this makes umask not
work for ocfs2 volume.

Fixes: 702e5bc ("ocfs2: use generic posix ACL infrastructure")
Signed-off-by: Junxiao Bi 
Cc: Gang He 
Cc: Mark Fasheh 
Cc: Joel Becker 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

nfs: if we have no valid attrs, then don't declare the attribute cache valid

2015-12-15T05:41:08+00:00

commit c812012f9ca7cf89c9e1a1cd512e6c3b5be04b85 upstream.

If we pass in an empty nfs_fattr struct to nfs_update_inode, it will
(correctly) not update any of the attributes, but it then clears the
NFS_INO_INVALID_ATTR flag, which indicates that the attributes are
up to date. Don't clear the flag if the fattr struct has no valid
attrs to apply.

Reviewed-by: Steve French 
Signed-off-by: Jeff Layton 
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman

nfs4: resend LAYOUTGET when there is a race that changes the seqid

2015-12-15T05:41:08+00:00

commit 4f2e9dce0c6348a95eaa56ade9bab18572221088 upstream.

pnfs_layout_process will check the returned layout stateid against what
the kernel has in-core. If it turns out that the stateid we received is
older, then we should resend the LAYOUTGET instead of falling back to
MDS I/O.

Signed-off-by: Jeff Layton 
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman