linux-toradex.git/fs, branch v4.6-rc6

Merge branch 'akpm' (patches from Andrew)

2016-04-29T18:21:22+00:00

Merge fixes from Andrew Morton:
 "20 fixes"

* emailed patches from Andrew Morton :
  Documentation/sysctl/vm.txt: update numa_zonelist_order description
  lib/stackdepot.c: allow the stack trace hash to be zero
  rapidio: fix potential NULL pointer dereference
  mm/memory-failure: fix race with compound page split/merge
  ocfs2/dlm: return zero if deref_done message is successfully handled
  Ananth has moved
  kcov: don't profile branches in kcov
  kcov: don't trace the code coverage code
  mm: wake kcompactd before kswapd's short sleep
  .mailmap: add Frank Rowand
  mm/hwpoison: fix wrong num_poisoned_pages accounting
  mm: call swap_slot_free_notify() with page lock held
  mm: vmscan: reclaim highmem zone if buffer_heads is over limit
  numa: fix /proc//numa_maps for THP
  mm/huge_memory: replace VM_NO_THP VM_BUG_ON with actual VMA check
  mailmap: fix Krzysztof Kozlowski's misspelled name
  thp: keep huge zero page pinned until tlb flush
  mm: exclude HugeTLB pages from THP page_mapped() logic
  kexec: export OFFSET(page.compound_head) to find out compound tail page
  kexec: update VMCOREINFO for compound_order/dtor

ocfs2/dlm: return zero if deref_done message is successfully handled

2016-04-29T02:34:04+00:00

dlm_deref_lockres_done_handler() should return zero if the message is
successfully handled.

Fixes: 60d663cb5273 ("ocfs2/dlm: add DEREF_DONE message").
Signed-off-by: xuejiufei 
Reviewed-by: Joseph Qi 
Cc: Mark Fasheh 
Cc: Joel Becker 
Cc: Junxiao Bi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

numa: fix /proc//numa_maps for THP

2016-04-29T02:34:04+00:00

In gather_pte_stats() a THP pmd is cast into a pte, which is wrong
because the layouts may differ depending on the architecture.  On s390
this will lead to inaccurate numa_maps accounting in /proc because of
misguided pte_present() and pte_dirty() checks on the fake pte.

On other architectures pte_present() and pte_dirty() may work by chance,
but there may be an issue with direct-access (dax) mappings w/o
underlying struct pages when HAVE_PTE_SPECIAL is set and THP is
available.  In vm_normal_page() the fake pte will be checked with
pte_special() and because there is no "special" bit in a pmd, this will
always return false and the VM_PFNMAP | VM_MIXEDMAP checking will be
skipped.  On dax mappings w/o struct pages, an invalid struct page
pointer would then be returned that can crash the kernel.

This patch fixes the numa_maps THP handling by introducing new "_pmd"
variants of the can_gather_numa_stats() and vm_normal_page() functions.

Signed-off-by: Gerald Schaefer 
Cc: Naoya Horiguchi 
Cc: "Kirill A . Shutemov" 
Cc: Konstantin Khlebnikov 
Cc: Michal Hocko 
Cc: Vlastimil Babka 
Cc: Jerome Marchand 
Cc: Johannes Weiner 
Cc: Dave Hansen 
Cc: Mel Gorman 
Cc: Dan Williams 
Cc: Martin Schwidefsky 
Cc: Heiko Carstens 
Cc: Michael Holzheu 
Cc: 	[4.3+]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

2016-04-29T01:59:24+00:00

Pull Ceph fixes from Sage Weil:
 "There is a lifecycle fix in the auth code, a fix for a narrow race
  condition on map, and a helpful message in the log when there is a
  feature mismatch (which happens frequently now that the default
  server-side options have changed)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  rbd: report unsupported features to syslog
  rbd: fix rbd map vs notify races
  libceph: make authorizer destruction independent of ceph_auth_client

devpts: more pty driver interface cleanups

2016-04-26T22:47:32+00:00

This is more prep-work for the upcoming pty changes.  Still just code
cleanup with no actual semantic changes.

This removes a bunch pointless complexity by just having the slave pty
side remember the dentry associated with the devpts slave rather than
the inode.  That allows us to remove all the "look up the dentry" code
for when we want to remove it again.

Together with moving the tty pointer from "inode->i_private" to
"dentry->d_fsdata" and getting rid of pointless inode locking, this
removes about 30 lines of code.  Not only is the end result smaller,
it's simpler and easier to understand.

The old code, for example, depended on the d_find_alias() to not just
find the dentry, but also to check that it is still hashed, which in
turn validated the tty pointer in the inode.

That is a _very_ roundabout way to say "invalidate the cached tty
pointer when the dentry is removed".

The new code just does

	dentry->d_fsdata = NULL;

in devpts_pty_kill() instead, invalidating the tty pointer rather more
directly and obviously.  Don't do something complex and subtle when the
obvious straightforward approach will do.

The rest of the patch (ie apart from code deletion and the above tty
pointer clearing) is just switching the calling convention to pass the
dentry or file pointer around instead of the inode.

Cc: Eric Biederman 
Cc: Peter Anvin 
Cc: Andy Lutomirski 
Cc: Al Viro 
Cc: Peter Hurley 
Cc: Serge Hallyn 
Cc: Willy Tarreau 
Cc: Aurelien Jarno 
Cc: Alan Cox 
Cc: Jann Horn 
Cc: Greg KH 
Cc: Jiri Slaby 
Cc: Florian Weimer 
Signed-off-by: Linus Torvalds

libceph: make authorizer destruction independent of ceph_auth_client

2016-04-25T18:54:13+00:00

Starting the kernel client with cephx disabled and then enabling cephx
and restarting userspace daemons can result in a crash:

    [262671.478162] BUG: unable to handle kernel paging request at ffffebe000000000
    [262671.531460] IP: [] kfree+0x5a/0x130
    [262671.584334] PGD 0
    [262671.635847] Oops: 0000 [#1] SMP
    [262672.055841] CPU: 22 PID: 2961272 Comm: kworker/22:2 Not tainted 4.2.0-34-generic #39~14.04.1-Ubuntu
    [262672.162338] Hardware name: Dell Inc. PowerEdge R720/068CDY, BIOS 2.4.3 07/09/2014
    [262672.268937] Workqueue: ceph-msgr con_work [libceph]
    [262672.322290] task: ffff88081c2d0dc0 ti: ffff880149ae8000 task.ti: ffff880149ae8000
    [262672.428330] RIP: 0010:[]  [] kfree+0x5a/0x130
    [262672.535880] RSP: 0018:ffff880149aeba58  EFLAGS: 00010286
    [262672.589486] RAX: 000001e000000000 RBX: 0000000000000012 RCX: ffff8807e7461018
    [262672.695980] RDX: 000077ff80000000 RSI: ffff88081af2be04 RDI: 0000000000000012
    [262672.803668] RBP: ffff880149aeba78 R08: 0000000000000000 R09: 0000000000000000
    [262672.912299] R10: ffffebe000000000 R11: ffff880819a60e78 R12: ffff8800aec8df40
    [262673.021769] R13: ffffffffc035f70f R14: ffff8807e5b138e0 R15: ffff880da9785840
    [262673.131722] FS:  0000000000000000(0000) GS:ffff88081fac0000(0000) knlGS:0000000000000000
    [262673.245377] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    [262673.303281] CR2: ffffebe000000000 CR3: 0000000001c0d000 CR4: 00000000001406e0
    [262673.417556] Stack:
    [262673.472943]  ffff880149aeba88 ffff88081af2be04 ffff8800aec8df40 ffff88081af2be04
    [262673.583767]  ffff880149aeba98 ffffffffc035f70f ffff880149aebac8 ffff8800aec8df00
    [262673.694546]  ffff880149aebac8 ffffffffc035c89e ffff8807e5b138e0 ffff8805b047f800
    [262673.805230] Call Trace:
    [262673.859116]  [] ceph_x_destroy_authorizer+0x1f/0x50 [libceph]
    [262673.968705]  [] ceph_auth_destroy_authorizer+0x3e/0x60 [libceph]
    [262674.078852]  [] put_osd+0x45/0x80 [libceph]
    [262674.134249]  [] remove_osd+0xae/0x140 [libceph]
    [262674.189124]  [] __reset_osd+0x103/0x150 [libceph]
    [262674.243749]  [] kick_requests+0x223/0x460 [libceph]
    [262674.297485]  [] ceph_osdc_handle_map+0x282/0x5e0 [libceph]
    [262674.350813]  [] dispatch+0x4e/0x720 [libceph]
    [262674.403312]  [] try_read+0x3d1/0x1090 [libceph]
    [262674.454712]  [] ? dequeue_entity+0x152/0x690
    [262674.505096]  [] con_work+0xcb/0x1300 [libceph]
    [262674.555104]  [] process_one_work+0x14e/0x3d0
    [262674.604072]  [] worker_thread+0x11a/0x470
    [262674.652187]  [] ? rescuer_thread+0x310/0x310
    [262674.699022]  [] kthread+0xd2/0xf0
    [262674.744494]  [] ? kthread_create_on_node+0x1c0/0x1c0
    [262674.789543]  [] ret_from_fork+0x3f/0x70
    [262674.834094]  [] ? kthread_create_on_node+0x1c0/0x1c0

What happens is the following:

    (1) new MON session is established
    (2) old "none" ac is destroyed
    (3) new "cephx" ac is constructed
    ...
    (4) old OSD session (w/ "none" authorizer) is put
          ceph_auth_destroy_authorizer(ac, osd->o_auth.authorizer)

osd->o_auth.authorizer in the "none" case is just a bare pointer into
ac, which contains a single static copy for all services.  By the time
we get to (4), "none" ac, freed in (2), is long gone.  On top of that,
a new vtable installed in (3) points us at ceph_x_destroy_authorizer(),
so we end up trying to destroy a "none" authorizer with a "cephx"
destructor operating on invalid memory!

To fix this, decouple authorizer destruction from ac and do away with
a single static "none" authorizer by making a copy for each OSD or MDS
session.  Authorizers themselves are independent of ac and so there is
no reason for destroy_authorizer() to be an ac op.  Make it an op on
the authorizer itself by turning ceph_authorizer into a real struct.

Fixes: http://tracker.ceph.com/issues/15447

Reported-by: Alan Zhang 
Signed-off-by: Ilya Dryomov 
Reviewed-by: Sage Weil

Merge branch 'ptmx-cleanup'

2016-04-19T23:36:18+00:00

Merge the ptmx internal interface cleanup branch.

This doesn't change semantics, but it should be a sane basis for
eventually getting the multi-instance devpts code into some sane shape
where we can get rid of the kernel config option.  Which we can
hopefully get done next merge window..

* ptmx-cleanup:
  devpts: clean up interface to pty drivers

devpts: clean up interface to pty drivers

2016-04-18T20:43:02+00:00

This gets rid of the horrible notion of having that

    struct inode *ptmx_inode

be the linchpin of the interface between the pty code and devpts.

By de-emphasizing the ptmx inode, a lot of things actually get cleaner,
and we will have a much saner way forward.  In particular, this will
allow us to associate with any particular devpts instance at open-time,
and not be artificially tied to one particular ptmx inode.

The patch itself is actually fairly straightforward, and apart from some
locking and return path cleanups it's pretty mechanical:

 - the interfaces that devpts exposes all take "struct pts_fs_info *"
   instead of "struct inode *ptmx_inode" now.

   NOTE! The "struct pts_fs_info" thing is a completely opaque structure
   as far as the pty driver is concerned: it's still declared entirely
   internally to devpts. So the pty code can't actually access it in any
   way, just pass it as a "cookie" to the devpts code.

 - the "look up the pts fs info" is now a single clear operation, that
   also does the reference count increment on the pts superblock.

   So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get
   ref" operation (devpts_get_ref(inode)), along with a "put ref" op
   (devpts_put_ref()).

 - the pty master "tty->driver_data" field now contains the pts_fs_info,
   not the ptmx inode.

 - because we don't care about the ptmx inode any more as some kind of
   base index, the ref counting can now drop the inode games - it just
   gets the ref on the superblock.

 - the pts_fs_info now has a back-pointer to the super_block. That's so
   that we can easily look up the information we actually need. Although
   quite often, the pts fs info was actually all we wanted, and not having
   to look it up based on some magical inode makes things more
   straightforward.

In particular, now that "devpts_get_ref(inode)" operation should really
be the *only* place we need to look up what devpts instance we're
associated with, and we do it exactly once, at ptmx_open() time.

The other side of this is that one ptmx node could now be associated
with multiple different devpts instances - you could have a single
/dev/ptmx node, and then have multiple mount namespaces with their own
instances of devpts mounted on /dev/pts/.  And that's all perfectly sane
in a model where we just look up the pts instance at open time.

This will eventually allow us to get rid of our odd single-vs-multiple
pts instance model, but this patch in itself changes no semantics, only
an internal binding model.

Cc: Eric Biederman 
Cc: Peter Anvin 
Cc: Andy Lutomirski 
Cc: Al Viro 
Cc: Peter Hurley 
Cc: Serge Hallyn 
Cc: Willy Tarreau 
Cc: Aurelien Jarno 
Cc: Alan Cox 
Cc: Jann Horn 
Cc: Greg KH 
Cc: Jiri Slaby 
Cc: Florian Weimer 
Signed-off-by: Linus Torvalds

Merge tag 'driver-core-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2016-04-17T03:53:50+00:00

Pull misc fixes from Greg KH:
 "Here are three small fixes for 4.6-rc4.

  Two fix up some lz4 issues with big endian systems, and the remaining
  one resolves a minor debugfs issue that was reported.

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

* tag 'driver-core-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  lib: lz4: cleanup unaligned access efficiency detection
  lib: lz4: fixed zram with lz4 on big endian machines
  debugfs: Make automount point inodes permanently empty

Merge tag 'for-linus-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

2016-04-15T01:22:42+00:00

Pull f2fs/fscrypto fixes from Jaegeuk Kim:
 "In addition to f2fs/fscrypto fixes, I've added one patch which
  prevents RCU mode lookup in d_revalidate, as Al mentioned.

  These patches fix f2fs and fscrypto based on -rc3 bug fixes in ext4
  crypto, which have not yet been fully propagated as follows.

   - use of dget_parent and file_dentry to avoid crashes
   - disallow RCU-mode lookup in d_invalidate
   - disallow -ENOMEM in the core data encryption path"

* tag 'for-linus-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
  ext4/fscrypto: avoid RCU lookup in d_revalidate
  fscrypto: don't let data integrity writebacks fail with ENOMEM
  f2fs: use dget_parent and file_dentry in f2fs_file_open
  fscrypto: use dget_parent() in fscrypt_d_revalidate()