review.tizen.org Git - platform/kernel/linux-rpi.git/log

Merge branch 'for-linus-4.8' of git://git./linux/kernel/git/mason/linux-btrfs

Pull btrfs fixes from Chris Mason:
"We've queued up a few different fixes in here.  These range from
  enospc corners to fsync and quota fixes, and a few targeted at error
  handling for corrupt metadata/fuzzing"

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix lockdep warning on deadlock against an inode's log mutex
  Btrfs: detect corruption when non-root leaf has zero item
  Btrfs: check btree node's nritems
  btrfs: don't create or leak aliased root while cleaning up orphans
  Btrfs: fix em leak in find_first_block_group
  btrfs: do not background blkdev_put()
  Btrfs: clarify do_chunk_alloc()'s return value
  btrfs: fix fsfreeze hang caused by delayed iputs deal
  btrfs: update btrfs_space_info's bytes_may_use timely
  btrfs: divide btrfs_update_reserved_bytes() into two functions
  btrfs: use correct offset for reloc_inode in prealloc_file_extent_cluster()
  btrfs: qgroup: Fix qgroup incorrectness caused by log replay
  btrfs: relocation: Fix leaking qgroups numbers on data extents
  btrfs: qgroup: Refactor btrfs_qgroup_insert_dirty_extent()
  btrfs: waiting on qgroup rescan should not always be interruptible
  btrfs: properly track when rescan worker is running
  btrfs: flush_space: treat return value of do_chunk_alloc properly
  Btrfs: add ASSERT for block group's memory leak
  btrfs: backref: Fix soft lockup in __merge_refs function
  Btrfs: fix memory leak of reloc_root

Merge tag 'dlm-4.8-fixes' of git://git./linux/kernel/git/teigland/linux-dlm

Pull dlm fix from David Teigland:
"This fixes a bug introduced by recent debugfs cleanup"

* tag 'dlm-4.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
dlm: fix malfunction of dlm_tool caused by debugfs changes

Merge tag 'dm-4.8-fixes-3' of git://git./linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

- another stable fix for DM flakey (that tweaks the previous fix that
   didn't factor in expected 'drop_writes' behavior for read IO).

- a dm-log bio operation flags fix for the broader block changes that
   were merged during the 4.8 merge window.

* tag 'dm-4.8-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm log: fix unitialized bio operation flags
  dm flakey: fix reads to be issued if drop_writes configured

Merge tag 'iommu-fixes-v4.8-rc3' of git://git./linux/kernel/git/joro/iommu

Pull IOMMU fixes from Joerg Roedel:
"Fixes from Will Deacon:

   - fix a couple of thinkos in the CMDQ error handling and
     short-descriptor page table code that have been there since day one

   - disable stalling faults, since they may result in hardware deadlock

   - fix an accidental BUG() when passing disable_bypass=1 on the
     cmdline"

* tag 'iommu-fixes-v4.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/arm-smmu: Don't BUG() if we find aborting STEs with disable_bypass
  iommu/arm-smmu: Disable stalling faults for all endpoints
  iommu/arm-smmu: Fix CMDQ error handling
  iommu/io-pgtable-arm-v7s: Fix attributes when splitting blocks

Merge branch 'for-linus' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
"Here's a set of block fixes for the current 4.8-rc release.  This
  contains:

   - a fix for a secure erase regression, from Adrian.

   - a fix for an mmc use-after-free bug regression, also from Adrian.

   - potential zero pointer deference in bdev freezing, from Andrey.

   - a race fix for blk_set_queue_dying() from Bart.

   - a set of xen blkfront fixes from Bob Liu.

   - three small fixes for bcache, from Eric and Kent.

   - a fix for a potential invalid NVMe state transition, from Gabriel.

   - blk-mq CPU offline fix, preventing us from issuing and completing a
     request on the wrong queue.  From me.

   - revert two previous floppy changes, since they caused a user
     visibile regression.  A better fix is in the works.

   - ensure that we don't send down bios that have more than 256
     elements in them.  Fixes a crash with bcache, for example.  From
     Ming.

   - a fix for deferencing an error pointer with cgroup writeback.
     Fixes a regression.  From Vegard"

* 'for-linus' of git://git.kernel.dk/linux-block:
  mmc: fix use-after-free of struct request
  Revert "floppy: refactor open() flags handling"
  Revert "floppy: fix open(O_ACCMODE) for ioctl-only open"
  fs/block_dev: fix potential NULL ptr deref in freeze_bdev()
  blk-mq: improve warning for running a queue on the wrong CPU
  blk-mq: don't overwrite rq->mq_ctx
  block: make sure a big bio is split into at most 256 bvecs
  nvme: Fix nvme_get/set_features() with a NULL result pointer
  bdev: fix NULL pointer dereference
  xen-blkfront: free resources if xlvbd_alloc_gendisk fails
  xen-blkfront: introduce blkif_set_queue_limits()
  xen-blkfront: fix places not updated after introducing 64KB page granularity
  bcache: pr_err: more meaningful error message when nr_stripes is invalid
  bcache: RESERVE_PRIO is too small by one when prio_buckets() is a power of two.
  bcache: register_bcache(): call blkdev_put() when cache_alloc() fails
  block: Fix race triggered by blk_set_queue_dying()
  block: Fix secure erase
  nvme: Prevent controller state invalid transition

Merge branch 'for-linus' of git://git./linux/kernel/git/dtor/input

Pull input subsystem fixes from Dmitry Torokhov:
"Simply small driver fixups"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: ads7846 - remove redundant regulator_disable call
  Input: synaptics-rmi4 - fix register descriptor subpacket map construction
  Input: tegra-kbc - fix inverted reset logic
  Input: silead - use devm_gpiod_get
  Input: i8042 - set up shared ps2_cmd_mutex for AUX ports

Merge tag 'pci-v4.8-fixes-1' of git://git./linux/kernel/git/helgaas/pci

Pull PCI fixes from Bjorn Helgaas:
"Resource management:
   - Update "pci=resource_alignment" documentation (Mathias Koehrer)

  MSI:
   - Use positive flags in pci_alloc_irq_vectors() (Christoph Hellwig)
   - Call pci_intx() when using legacy interrupts in pci_alloc_irq_vectors() (Christoph Hellwig)

  Intel VMD host bridge driver:
   - Fix infinite loop executing irq's (Keith Busch)"

* tag 'pci-v4.8-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  x86/PCI: VMD: Fix infinite loop executing irq's
  PCI: Call pci_intx() when using legacy interrupts in pci_alloc_irq_vectors()
  PCI: Use positive flags in pci_alloc_irq_vectors()
  PCI: Update "pci=resource_alignment" documentation

dlm: fix malfunction of dlm_tool caused by debugfs changes

With the current kernel, `dlm_tool lockdebug` fails as below:

"dlm_tool lockdebug ED0BD86DCE724393918A1AE8FDBF1EE3
can't open /sys/kernel/debug/dlm/ED0BD86DCE724393918A1AE8FDBF1EE3:
Operation not permitted"

This is because table_open() depends on file->f_op to tell which
seq_file ops should be passed down. But, the original file ops in
file->f_op is replaced by "debugfs_full_proxy_file_operations" with
commit 49d200deaa68 ("debugfs: prevent access to removed files'
private data").

Currently, I can think up 2 solutions: 1st, replace
debugfs_create_file() with debugfs_create_file_unsafe();
2nd, make different table_open#() accordingly. The 1st one
is neat, but I don't thoroughly understand its risk. Maybe
someone has a better one.

Signed-off-by: Eric Ren <zren@suse.com>
Signed-off-by: David Teigland <teigland@redhat.com>

mmc: fix use-after-free of struct request

We call mmc_req_is_special() after having processed a request, but
it could be freed after that. Check that ahead of time, and use
the cached value.

Reported-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Fixes: c2df40dfb8c0 ("drivers: use req op accessor")

Signed-off-by: Jens Axboe <axboe@fb.com>

Revert "floppy: refactor open() flags handling"

This reverts commit 09954bad448791ef01202351d437abdd9497a804.

Revert "floppy: fix open(O_ACCMODE) for ioctl-only open"

This reverts commit ff06db1efb2ad6db06eb5b99b88a0c15a9cc9b0e.

fs/block_dev: fix potential NULL ptr deref in freeze_bdev()

Calling freeze_bdev() twice on the same block device without mounted
filesystem get_super() will return NULL, which will lead to NULL-ptr
dereference later in drop_super().

Check get_super() result to fix that.

Note, that this is a purely theoretical issue. We have only 3
freeze_bdev() callers. 2 of them are in filesystem code and used on a
device with mounted fs. The third one in lock_fs() has protection in
upper-layer code against freezing block device the second time without
thawing it first.

Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

Btrfs: fix lockdep warning on deadlock against an inode's log mutex

Commit 44f714dae50a ("Btrfs: improve performance on fsync against new
inode after rename/unlink"), which landed in 4.8-rc2, introduced a
possibility for a deadlock due to double locking of an inode's log mutex
by the same task, which lockdep reports with:

[23045.433975] =============================================
[23045.434748] [ INFO: possible recursive locking detected ]
[23045.435426] 4.7.0-rc6-btrfs-next-34+ #1 Not tainted
[23045.436044] ---------------------------------------------
[23045.436044] xfs_io/3688 is trying to acquire lock:
[23045.436044]  (&ei->log_mutex){+.+...}, at: [<ffffffffa038552d>] btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]
               but task is already holding lock:
[23045.436044]  (&ei->log_mutex){+.+...}, at: [<ffffffffa038552d>] btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]
               other info that might help us debug this:
[23045.436044]  Possible unsafe locking scenario:

[23045.436044]        CPU0
[23045.436044]        ----
[23045.436044]   lock(&ei->log_mutex);
[23045.436044]   lock(&ei->log_mutex);
[23045.436044]
                *** DEADLOCK ***

[23045.436044]  May be due to missing lock nesting notation

[23045.436044] 3 locks held by xfs_io/3688:
[23045.436044]  #0:  (&sb->s_type->i_mutex_key#15){+.+...}, at: [<ffffffffa035f2ae>] btrfs_sync_file+0x14e/0x425 [btrfs]
[23045.436044]  #1:  (sb_internal#2){.+.+.+}, at: [<ffffffff8118446b>] __sb_start_write+0x5f/0xb0
[23045.436044]  #2:  (&ei->log_mutex){+.+...}, at: [<ffffffffa038552d>] btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]
               stack backtrace:
[23045.436044] CPU: 4 PID: 3688 Comm: xfs_io Not tainted 4.7.0-rc6-btrfs-next-34+ #1
[23045.436044] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.1-0-gb3ef39f-prebuilt.qemu-project.org 04/01/2014
[23045.436044]  0000000000000000 ffff88022f5f7860 ffffffff8127074d ffffffff82a54b70
[23045.436044]  ffffffff82a54b70 ffff88022f5f7920 ffffffff81092897 ffff880228015d68
[23045.436044]  0000000000000000 ffffffff82a54b70 ffffffff829c3f00 ffff880228015d68
[23045.436044] Call Trace:
[23045.436044]  [<ffffffff8127074d>] dump_stack+0x67/0x90
[23045.436044]  [<ffffffff81092897>] __lock_acquire+0xcbb/0xe4e
[23045.436044]  [<ffffffff8109155f>] ? mark_lock+0x24/0x201
[23045.436044]  [<ffffffff8109179a>] ? mark_held_locks+0x5e/0x74
[23045.436044]  [<ffffffff81092de0>] lock_acquire+0x12f/0x1c3
[23045.436044]  [<ffffffff81092de0>] ? lock_acquire+0x12f/0x1c3
[23045.436044]  [<ffffffffa038552d>] ? btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]  [<ffffffffa038552d>] ? btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]  [<ffffffff814a51a4>] mutex_lock_nested+0x77/0x3a7
[23045.436044]  [<ffffffffa038552d>] ? btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]  [<ffffffffa039705e>] ? btrfs_release_delayed_node+0xb/0xd [btrfs]
[23045.436044]  [<ffffffffa038552d>] btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]  [<ffffffffa038552d>] ? btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]  [<ffffffff810a0ed1>] ? vprintk_emit+0x453/0x465
[23045.436044]  [<ffffffffa0385a61>] btrfs_log_inode+0x66e/0xc95 [btrfs]
[23045.436044]  [<ffffffffa03c084d>] log_new_dir_dentries+0x26c/0x359 [btrfs]
[23045.436044]  [<ffffffffa03865aa>] btrfs_log_inode_parent+0x4a6/0x628 [btrfs]
[23045.436044]  [<ffffffffa0387552>] btrfs_log_dentry_safe+0x5a/0x75 [btrfs]
[23045.436044]  [<ffffffffa035f464>] btrfs_sync_file+0x304/0x425 [btrfs]
[23045.436044]  [<ffffffff811acaf4>] vfs_fsync_range+0x8c/0x9e
[23045.436044]  [<ffffffff811acb22>] vfs_fsync+0x1c/0x1e
[23045.436044]  [<ffffffff811acc79>] do_fsync+0x31/0x4a
[23045.436044]  [<ffffffff811ace99>] SyS_fsync+0x10/0x14
[23045.436044]  [<ffffffff814a88e5>] entry_SYSCALL_64_fastpath+0x18/0xa8
[23045.436044]  [<ffffffff8108f039>] ? trace_hardirqs_off_caller+0x3f/0xaa

An example reproducer for this is:

   $ mkfs.btrfs -f /dev/sdb
   $ mount /dev/sdb /mnt
   $ mkdir /mnt/dir
   $ touch /mnt/dir/foo
   $ sync
   $ mv /mnt/dir/foo /mnt/dir/bar
   $ touch /mnt/dir/foo
   $ xfs_io -c "fsync" /mnt/dir/bar

This is because while logging the inode of file bar we end up logging its
parent directory (since its inode has an unlink_trans field matching the
current transaction id due to the rename operation), which in turn logs
the inodes for all its new dentries, so that the new inode for the new
file named foo gets logged which in turn triggered another logging attempt
for the inode we are fsync'ing, since that inode had an old name that
corresponds to the name of the new inode.

So fix this by ensuring that when logging the inode for a new dentry that
has a name matching an old name of some other inode, we don't log again
the original inode that we are fsync'ing.

Fixes: 44f714dae50a ("Btrfs: improve performance on fsync against new inode after rename/unlink")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

Btrfs: detect corruption when non-root leaf has zero item

Right now we treat leaf which has zero item as a valid one
because we could have an empty tree, that is, a root that is
also a leaf without any item, however, in the same case but
when the leaf is not a root, we can end up with hitting the
BUG_ON(1) in btrfs_extend_item() called by
setup_inline_extent_backref().

This makes us check the situation as a corruption if leaf is
not its own root.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

Btrfs: check btree node's nritems

When btree node (level = 1) has nritems which equals to zero,
we can end up with panic due to insert_ptr()'s

BUG_ON(slot > nritems);

where slot is 1 and nritems is 0, as copy_for_split() calls
insert_ptr(.., path->slots[1] + 1, ...);

A invalid value results in the whole mess, this adds the check
for btree's node nritems so that we stop reading block when
when something is wrong.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

btrfs: don't create or leak aliased root while cleaning up orphans

commit 909c3a22da3 (Btrfs: fix loading of orphan roots leading to BUG_ON)
avoids the BUG_ON but can add an aliased root to the dead_roots list or
leak the root.

Since we've already been loading roots into the radix tree, we should
use it before looking the root up on disk.

Cc: <stable@vger.kernel.org> # 4.5
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

Btrfs: fix em leak in find_first_block_group

We need to call free_extent_map() on the em we look up.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

btrfs: do not background blkdev_put()

At the end of unmount/dev-delete, if the device exclusive open is not
actually closed, then there might be a race with another program in
the userland who is trying to open the device in exclusive mode and
it may fail for eg:
unmount /btrfs; fsck /dev/x
btrfs dev del /dev/x /btrfs; fsck /dev/x
so here background blkdev_put() is not a choice

Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

Btrfs: clarify do_chunk_alloc()'s return value

Function start_transaction() can return ERR_PTR(1) when flush is
BTRFS_RESERVE_FLUSH_LIMIT, so the call graph is

start_transaction (return ERR_PTR(1))
  -> btrfs_block_rsv_add (return 1)
     -> reserve_metadata_bytes (return 1)
        -> flush_space (return 1)
           -> do_chunk_alloc  (return 1)

With BTRFS_RESERVE_FLUSH_LIMIT, if flush_space is already on the
flush_state of ALLOC_CHUNK and it successfully allocates a new
chunk, then instead of trying to reserve space again,
reserve_metadata_bytes returns 1 immediately.

Eventually the callers who call start_transaction() usually just
do the IS_ERR() check which ERR_PTR(1) can pass, then it'll get
a panic when dereferencing a pointer which is ERR_PTR(1).

The following patch fixes the above problem.
"btrfs: flush_space: treat return value of do_chunk_alloc properly"
https://patchwork.kernel.org/patch/7778651/

This add comments to clarify do_chunk_alloc()'s return value.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

btrfs: fix fsfreeze hang caused by delayed iputs deal

When running fstests generic/068, sometimes we got below deadlock:
  xfs_io          D ffff8800331dbb20     0  6697   6693 0x00000080
  ffff8800331dbb20 ffff88007acfc140 ffff880034d895c0 ffff8800331dc000
  ffff880032d243e8 fffffffeffffffff ffff880032d24400 0000000000000001
  ffff8800331dbb38 ffffffff816a9045 ffff880034d895c0 ffff8800331dbba8
  Call Trace:
  [<ffffffff816a9045>] schedule+0x35/0x80
  [<ffffffff816abab2>] rwsem_down_read_failed+0xf2/0x140
  [<ffffffff8118f5e1>] ? __filemap_fdatawrite_range+0xd1/0x100
  [<ffffffff8134f978>] call_rwsem_down_read_failed+0x18/0x30
  [<ffffffffa06631fc>] ? btrfs_alloc_block_rsv+0x2c/0xb0 [btrfs]
  [<ffffffff810d32b5>] percpu_down_read+0x35/0x50
  [<ffffffff81217dfc>] __sb_start_write+0x2c/0x40
  [<ffffffffa067f5d5>] start_transaction+0x2a5/0x4d0 [btrfs]
  [<ffffffffa067f857>] btrfs_join_transaction+0x17/0x20 [btrfs]
  [<ffffffffa068ba34>] btrfs_evict_inode+0x3c4/0x5d0 [btrfs]
  [<ffffffff81230a1a>] evict+0xba/0x1a0
  [<ffffffff812316b6>] iput+0x196/0x200
  [<ffffffffa06851d0>] btrfs_run_delayed_iputs+0x70/0xc0 [btrfs]
  [<ffffffffa067f1d8>] btrfs_commit_transaction+0x928/0xa80 [btrfs]
  [<ffffffffa0646df0>] btrfs_freeze+0x30/0x40 [btrfs]
  [<ffffffff81218040>] freeze_super+0xf0/0x190
  [<ffffffff81229275>] do_vfs_ioctl+0x4a5/0x5c0
  [<ffffffff81003176>] ? do_audit_syscall_entry+0x66/0x70
  [<ffffffff810038cf>] ? syscall_trace_enter_phase1+0x11f/0x140
  [<ffffffff81229409>] SyS_ioctl+0x79/0x90
  [<ffffffff81003c12>] do_syscall_64+0x62/0x110
  [<ffffffff816acbe1>] entry_SYSCALL64_slow_path+0x25/0x25

>From this warning, freeze_super() already holds SB_FREEZE_FS, but
btrfs_freeze() will call btrfs_commit_transaction() again, if
btrfs_commit_transaction() finds that it has delayed iputs to handle,
it'll start_transaction(), which will try to get SB_FREEZE_FS lock
again, then deadlock occurs.

The root cause is that in btrfs, sync_filesystem(sb) does not make
sure all metadata is updated. There still maybe some codes adding
delayed iputs, see below sample race window:

         CPU1                                  |         CPU2
|-> freeze_super()                             |
    |-> sync_filesystem(sb);                   |
    |                                          |-> cleaner_kthread()
    |                                          |   |-> btrfs_delete_unused_bgs()
    |                                          |       |-> btrfs_remove_chunk()
    |                                          |           |-> btrfs_remove_block_group()
    |                                          |               |-> btrfs_add_delayed_iput()
    |                                          |
    |-> sb->s_writers.frozen = SB_FREEZE_FS;   |
    |-> sb_wait_write(sb, SB_FREEZE_FS);       |
    |   acquire SB_FREEZE_FS lock.             |
    |                                          |
    |-> btrfs_freeze()                         |
        |-> btrfs_commit_transaction()         |
            |-> btrfs_run_delayed_iputs()      |
            |   will handle delayed iputs,     |
            |   that means start_transaction() |
            |   will be called, which will try |
            |   to get SB_FREEZE_FS lock.      |

To fix this issue, introduce a "int fs_frozen" to record internally whether
fs has been frozen. If fs has been frozen, we can not handle delayed iputs.

Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment to btrfs_freeze ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

btrfs: update btrfs_space_info's bytes_may_use timely

This patch can fix some false ENOSPC errors, below test script can
reproduce one false ENOSPC error:
#!/bin/bash
dd if=/dev/zero of=fs.img bs=$((1024*1024)) count=128
dev=$(losetup --show -f fs.img)
mkfs.btrfs -f -M $dev
mkdir /tmp/mntpoint
mount $dev /tmp/mntpoint
cd /tmp/mntpoint
xfs_io -f -c "falloc 0 $((64*1024*1024))" testfile

Above script will fail for ENOSPC reason, but indeed fs still has free
space to satisfy this request. Please see call graph:
btrfs_fallocate()
|-> btrfs_alloc_data_chunk_ondemand()
|   bytes_may_use += 64M
|-> btrfs_prealloc_file_range()
    |-> btrfs_reserve_extent()
        |-> btrfs_add_reserved_bytes()
        |   alloc_type is RESERVE_ALLOC_NO_ACCOUNT, so it does not
        |   change bytes_may_use, and bytes_reserved += 64M. Now
        |   bytes_may_use + bytes_reserved == 128M, which is greater
        |   than btrfs_space_info's total_bytes, false enospc occurs.
        |   Note, the bytes_may_use decrease operation will be done in
        |   end of btrfs_fallocate(), which is too late.

Here is another simple case for buffered write:
                    CPU 1              |              CPU 2
                                       |
|-> cow_file_range()                   |-> __btrfs_buffered_write()
    |-> btrfs_reserve_extent()         |   |
    |                                  |   |
    |                                  |   |
    |    .....                         |   |-> btrfs_check_data_free_space()
    |                                  |
    |                                  |
    |-> extent_clear_unlock_delalloc() |

In CPU 1, btrfs_reserve_extent()->find_free_extent()->
btrfs_add_reserved_bytes() do not decrease bytes_may_use, the decrease
operation will be delayed to be done in extent_clear_unlock_delalloc().
Assume in this case, btrfs_reserve_extent() reserved 128MB data, CPU2's
btrfs_check_data_free_space() tries to reserve 100MB data space.
If
100MB > data_sinfo->total_bytes - data_sinfo->bytes_used -
data_sinfo->bytes_reserved - data_sinfo->bytes_pinned -
data_sinfo->bytes_readonly - data_sinfo->bytes_may_use
btrfs_check_data_free_space() will try to allcate new data chunk or call
btrfs_start_delalloc_roots(), or commit current transaction in order to
reserve some free space, obviously a lot of work. But indeed it's not
necessary as long as decreasing bytes_may_use timely, we still have
free space, decreasing 128M from bytes_may_use.

To fix this issue, this patch chooses to update bytes_may_use for both
data and metadata in btrfs_add_reserved_bytes(). For compress path, real
extent length may not be equal to file content length, so introduce a
ram_bytes argument for btrfs_reserve_extent(), find_free_extent() and
btrfs_add_reserved_bytes(), it's becasue bytes_may_use is increased by
file content length. Then compress path can update bytes_may_use
correctly. Also now we can discard RESERVE_ALLOC_NO_ACCOUNT, RESERVE_ALLOC
and RESERVE_FREE.

As we know, usually EXTENT_DO_ACCOUNTING is used for error path. In
run_delalloc_nocow(), for inode marked as NODATACOW or extent marked as
PREALLOC, we also need to update bytes_may_use, but can not pass
EXTENT_DO_ACCOUNTING, because it also clears metadata reservation, so
here we introduce EXTENT_CLEAR_DATA_RESV flag to indicate btrfs_clear_bit_hook()
to update btrfs_space_info's bytes_may_use.

Meanwhile __btrfs_prealloc_file_range() will call
btrfs_free_reserved_data_space() internally for both sucessful and failed
path, btrfs_prealloc_file_range()'s callers does not need to call
btrfs_free_reserved_data_space() any more.

Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

btrfs: divide btrfs_update_reserved_bytes() into two functions

This patch divides btrfs_update_reserved_bytes() into
btrfs_add_reserved_bytes() and btrfs_free_reserved_bytes(), and
next patch will extend btrfs_add_reserved_bytes（）to fix some
false ENOSPC error, please see later patch for detailed info.

Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

btrfs: use correct offset for reloc_inode in prealloc_file_extent_cluster()

In prealloc_file_extent_cluster(), btrfs_check_data_free_space() uses
wrong file offset for reloc_inode, it uses cluster->start and cluster->end,
which indeed are extent's bytenr. The correct value should be
cluster->[start|end] minus block group's start bytenr.

start bytenr   cluster->start
|              |     extent      |   extent   | ...| extent |
|----------------------------------------------------------------|
|                block group reloc_inode                         |

Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

btrfs: qgroup: Fix qgroup incorrectness caused by log replay

When doing log replay at mount time(after power loss), qgroup will leak
numbers of replayed data extents.

The cause is almost the same of balance.
So fix it by manually informing qgroup for owner changed extents.

The bug can be detected by btrfs/119 test case.

Cc: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-and-Tested-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

btrfs: relocation: Fix leaking qgroups numbers on data extents

This patch fixes a REGRESSION introduced in 4.2, caused by the big quota
rework.

When balancing data extents, qgroup will leak all its numbers for
relocated data extents.

The relocation is done in the following steps for data extents:
1) Create data reloc tree and inode
2) Copy all data extents to data reloc tree
   And commit transaction
3) Create tree reloc tree(special snapshot) for any related subvolumes
4) Replace file extent in tree reloc tree with new extents in data reloc
   tree
   And commit transaction
5) Merge tree reloc tree with original fs, by swapping tree blocks

For 1)~4), since tree reloc tree and data reloc tree doesn't count to
qgroup, everything is OK.

But for 5), the swapping of tree blocks will only info qgroup to track
metadata extents.

If metadata extents contain file extents, qgroup number for file extents
will get lost, leading to corrupted qgroup accounting.

The fix is, before commit transaction of step 5), manually info qgroup to
track all file extents in data reloc tree.
Since at commit transaction time, the tree swapping is done, and qgroup
will account these data extents correctly.

Cc: Mark Fasheh <mfasheh@suse.de>
Reported-by: Mark Fasheh <mfasheh@suse.de>
Reported-by: Filipe Manana <fdmanana@gmail.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

btrfs: qgroup: Refactor btrfs_qgroup_insert_dirty_extent()

Refactor btrfs_qgroup_insert_dirty_extent() function, to two functions:
1. btrfs_qgroup_insert_dirty_extent_nolock()
   Almost the same with original code.
   For delayed_ref usage, which has delayed refs locked.

   Change the return value type to int, since caller never needs the
   pointer, but only needs to know if they need to free the allocated
   memory.

2. btrfs_qgroup_insert_dirty_extent()
   The more encapsulated version.

   Will do the delayed_refs lock, memory allocation, quota enabled check
   and other things.

The original design is to keep exported functions to minimal, but since
more btrfs hacks exposed, like replacing path in balance, we need to
record dirty extents manually, so we have to add such functions.

Also, add comment for both functions, to info developers how to keep
qgroup correct when doing hacks.

Cc: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-and-Tested-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

btrfs: waiting on qgroup rescan should not always be interruptible

We wait on qgroup rescan completion in three places: file system
shutdown, the quota disable ioctl, and the rescan wait ioctl.  If the
user sends a signal while we're waiting, we continue happily along.  This
is expected behavior for the rescan wait ioctl.  It's racy in the shutdown
path but mostly works due to other unrelated synchronization points.
In the quota disable path, it Oopses the kernel pretty much immediately.

Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

btrfs: properly track when rescan worker is running

The qgroup_flags field is overloaded such that it reflects the on-disk
status of qgroups and the runtime state.  The BTRFS_QGROUP_STATUS_FLAG_RESCAN
flag is used to indicate that a rescan operation is in progress, but if
the file system is unmounted while a rescan is running, the rescan
operation is paused.  If the file system is then mounted read-only,
the flag will still be present but the rescan operation will not have
been resumed.  When we go to umount, btrfs_qgroup_wait_for_completion
will see the flag and interpret it to mean that the rescan worker is
still running and will wait for a completion that will never come.

This patch uses a separate flag to indicate when the worker is
running.  The locking and state surrounding the qgroup rescan worker
needs a lot of attention beyond this patch but this is enough to
avoid a hung umount.

Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by; Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

btrfs: flush_space: treat return value of do_chunk_alloc properly

do_chunk_alloc returns 1 when it succeeds to allocate a new chunk.
But flush_space will not convert this to 0, and will also return 1.
As a result, reserve_metadata_bytes will think that flush_space failed,
and may potentially return this value "1" to the caller (depends how
reserve_metadata_bytes was called). The caller will also treat this as an error.
For example, btrfs_block_rsv_refill does:

int ret = -ENOSPC;
...
ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
if (!ret) {
block_rsv_add_bytes(block_rsv, num_bytes, 0);
return 0;
}

return ret;

So it will return -ENOSPC.

Signed-off-by: Alex Lyakas <alex@zadarastorage.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

Btrfs: add ASSERT for block group's memory leak

This adds several ASSERT()' s to report memory leak of block group cache.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

btrfs: backref: Fix soft lockup in __merge_refs function

When over 1000 file extents refers to one extent, find_parent_nodes()
will be obviously slow, due to the O(n^2)~O(n^3) loops inside
__merge_refs().

The following ftrace shows the cubic growth of execution time:

256 refs
5) + 91.768 us   |  __add_keyed_refs.isra.12 [btrfs]();
5)   1.447 us    |  __add_missing_keys.isra.13 [btrfs]();
5) ! 114.544 us  |  __merge_refs [btrfs]();
5) ! 136.399 us  |  __merge_refs [btrfs]();

512 refs
6) ! 279.859 us  |  __add_keyed_refs.isra.12 [btrfs]();
6)   3.164 us    |  __add_missing_keys.isra.13 [btrfs]();
6) ! 442.498 us  |  __merge_refs [btrfs]();
6) # 2091.073 us |  __merge_refs [btrfs]();

and 1024 refs
7) ! 368.683 us  |  __add_keyed_refs.isra.12 [btrfs]();
7)   4.810 us    |  __add_missing_keys.isra.13 [btrfs]();
7) # 2043.428 us |  __merge_refs [btrfs]();
7) * 18964.23 us |  __merge_refs [btrfs]();

And sort them into the following char:
(Unit: us)
------------------------------------------------------------------------
Trace function        | 256 ref        | 512 refs      | 1024 refs    |
------------------------------------------------------------------------
__add_keyed_refs      | 91             | 249           | 368          |
__add_missing_keys    | 1              | 3             | 4            |
__merge_refs 1st call | 114            | 442           | 2043         |
__merge_refs 2nd call | 136            | 2091          | 18964        |
------------------------------------------------------------------------

We can see the that __add_keyed_refs() grows almost in linear behavior.
And __add_missing_keys() in this case doesn't change much or takes much
time.

While for the 1st __merge_refs() it's square growth
for the 2nd __merge_refs() call it's cubic growth.

It's no doubt that merge_refs() will take a long long time to execute if
the number of refs continues its grows.

So add a cond_resced() into the loop of __merge_refs().

Although this will solve the problem of soft lockup, we need to use the
new rb_tree based structure introduced by Lu Fengqi to really solve the
long execution time.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

Btrfs: fix memory leak of reloc_root

When some critical errors occur and FS would be flipped into RO,
if we have an on-going balance, we can end up with a memory leak
of root->reloc_root since btrfs_drop_snapshots() bails out
without freeing reloc_root at the very early start.

However, we're not able to free reloc_root in btrfs_drop_snapshots()
because its caller, merge_reloc_roots(), still needs to access it to
cleanup reloc_root's rbtree.

This makes us free reloc_root when we're going to free fs/file roots.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

Merge branch 'for-rc' of git://git./linux/kernel/git/rzhang/linux

Pull thermal fixes from Zhang Rui:

- Fix cpu_cooling to have separate thermal_cooling_device_ops
   structures for cpus with and without power model, to avoid NULL
   dereference in cpufreq_state2power.  From Brendan Jackman.

- Fix a possible NULL dereference in imx_thermal driver.  From Corentin
   LABBE.

- Another two trivial fixes, one typo fix and one deleting module
   owner.  From Caesar Wang and Markus Elfring.

* 'for-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
  thermal: imx: fix a possible NULL dereference
  thermal: trivial: fix the typo
  Thermal-INT3406: Delete owner assignment
  thermal: cpu_cooling: Fix NULL dereference in cpufreq_state2power

dm log: fix unitialized bio operation flags

Commit e6047149db ("dm: use bio op accessors") switched DM over to
using bio_set_op_attrs() but didn't take care to initialize
lc->io_req.bi_op_flags in dm-log.c:rw_header(). This caused
rw_header()'s call to dm_io() to make bio->bi_op_flags be uninitialized
in dm-io.c:do_region(), which ultimately resulted in a SCSI BUG() in
sd_init_command().

Also, adjust rw_header() and its callers to use REQ_OP_{READ|WRITE}.

Fixes: e6047149db ("dm: use bio op accessors")
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Reviewed-by: Shaun Tancheff <shaun.tancheff@seagate.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

dm flakey: fix reads to be issued if drop_writes configured

v4.8-rc3 commit 99f3c90d0d ("dm flakey: error READ bios during the
down_interval") overlooked the 'drop_writes' feature, which is meant to
allow reads to be issued rather than errored, during the down_interval.

Fixes: 99f3c90d0d ("dm flakey: error READ bios during the down_interval")
Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org

blk-mq: improve warning for running a queue on the wrong CPU

__blk_mq_run_hw_queue() currently warns if we are running the queue on a
CPU that isn't set in its mask. However, this can happen if a CPU is
being offlined, and the workqueue handling will place the work on CPU0
instead. Improve the warning so that it only triggers if the batch cpu
in the hardware queue is currently online. If it triggers for that
case, then it's indicative of a flow problem in blk-mq, so we want to
retain it for that case.

Signed-off-by: Jens Axboe <axboe@fb.com>

blk-mq: don't overwrite rq->mq_ctx

We do this in a few places, if the CPU is offline. This isn't allowed,
though, since on multi queue hardware, we can't just move a request
from one software queue to another, if they map to different hardware
queues. The request and tag isn't valid on another hardware queue.

This can happen if plugging races with CPU offlining. But it does
no harm, since it can only happen in the window where we are
currently busy freezing the queue and flushing IO, in preparation
for redoing the software <-> hardware queue mappings.

Signed-off-by: Jens Axboe <axboe@fb.com>

Merge branch 'for-linus-4.8-rc4' of git://git./linux/kernel/git/rw/uml

Pull UML fix from Richard Weinberger:
"This contains a fix for a build regression introduced during the merge
window"

* 'for-linus-4.8-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
um: Don't discard .text.exit section

Merge tag 'upstream-4.8-rc4' of git://git.infradead.org/linux-ubifs

Pull UBIFS fixes from Richard Weinberger:
"This pull requests contains fixes for two issues in UBI and UBIFS:

   - wrong UBIFS assertion.
   - a UBIFS xattr regression"

* tag 'upstream-4.8-rc4' of git://git.infradead.org/linux-ubifs:
  ubifs: Fix xattr generic handler usage
  ubifs: Fix assertion in layout_in_gaps()

Merge tag 'for-linus-4.8b-rc3-tag' of git://git./linux/kernel/git/xen/tip

Pull xen regression fix from David Vrabel:
"Fix a regression in the xenbus device preventing userspace tools from
  working"

* tag 'for-linus-4.8b-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: change the type of xen_vcpu_id to uint32_t
  xenbus: don't look up transaction IDs for ordinary writes

xen: change the type of xen_vcpu_id to uint32_t

We pass xen_vcpu_id mapping information to hypercalls which require
uint32_t type so it would be cleaner to have it as uint32_t. The
initializer to -1 can be dropped as we always do the mapping before using
it and we never check the 'not set' value anyway.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>

xenbus: don't look up transaction IDs for ordinary writes

This should really only be done for XS_TRANSACTION_END messages, or
else at least some of the xenstore-* tools don't work anymore.

Fixes: 0beef634b8 ("xenbus: don't BUG() on user mode induced condition")
Reported-by: Richard Schütz <rschuetz@uni-koblenz.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Richard Schütz <rschuetz@uni-koblenz.de>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>

block: make sure a big bio is split into at most 256 bvecs

After arbitrary bio size was introduced, the incoming bio may
be very big. We have to split the bio into small bios so that
each holds at most BIO_MAX_PAGES bvecs for safety reason, such
as bio_clone().

This patch fixes the following kernel crash:

> [  172.660142] BUG: unable to handle kernel NULL pointer dereference at 0000000000000028
> [  172.660229] IP: [<ffffffff811e53b4>] bio_trim+0xf/0x2a
> [  172.660289] PGD 7faf3e067 PUD 7f9279067 PMD 0
> [  172.660399] Oops: 0000 [#1] SMP
> [...]
> [  172.664780] Call Trace:
> [  172.664813]  [<ffffffffa007f3be>] ? raid1_make_request+0x2e8/0xad7 [raid1]
> [  172.664846]  [<ffffffff811f07da>] ? blk_queue_split+0x377/0x3d4
> [  172.664880]  [<ffffffffa005fb5f>] ? md_make_request+0xf6/0x1e9 [md_mod]
> [  172.664912]  [<ffffffff811eb860>] ? generic_make_request+0xb5/0x155
> [  172.664947]  [<ffffffffa0445c89>] ? prio_io+0x85/0x95 [bcache]
> [  172.664981]  [<ffffffffa0448252>] ? register_cache_set+0x355/0x8d0 [bcache]
> [  172.665016]  [<ffffffffa04497d3>] ? register_bcache+0x1006/0x1174 [bcache]

The issue can be reproduced by the following steps:
- create one raid1 over two virtio-blk
- build bcache device over the above raid1 and another cache device
and bucket size is set as 2Mbytes
- set cache mode as writeback
- run random write over ext4 on the bcache device

Fixes: 54efd50(block: make generic_make_request handle arbitrarily sized bios)
Reported-by: Sebastian Roesner <sroesner-kernelorg@roesner-online.de>
Reported-by: Eric Wheeler <bcache@lists.ewheeler.net>
Cc: stable@vger.kernel.org (4.3+)
Cc: Shaohua Li <shli@fb.com>
Acked-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

nvme: Fix nvme_get/set_features() with a NULL result pointer

nvme_set_features() callers seem to expect that passing NULL as the
result pointer is acceptable. Teach nvme_set_features() not to try to
write to the NULL address.

For symmetry, make the same change to nvme_get_features(), despite the
fact that all current callers pass a valid result pointer.

I assume that this bug hasn't been reported in practice because
the callers that pass NULL are all in the SCSI translation layer
and no one uses the relevant operations.

Cc: stable@vger.kernel.org
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>

Merge tag 'for_linus' of git://git./linux/kernel/git/mst/vhost

Pull vhost bugfix from Michael Tsirkin:
"This includes a single bugfix for vhost-scsi"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
vhost/scsi: fix reuse of &vq->iov[out] in response

Merge tag 'for-f2fs-v4.8-rc4' of git://git./linux/kernel/git/jaegeuk/f2fs

Pull f2fs fixes from Jaegeuk Kim:
- fsmark regression
- i_size race condition
- wrong conditions in f2fs_move_file_range

* tag 'for-f2fs-v4.8-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
  f2fs: avoid potential deadlock in f2fs_move_file_range
  f2fs: allow copying file range only in between regular files
  Revert "f2fs: move i_size_write in f2fs_write_end"
  Revert "f2fs: use percpu_rw_semaphore"

x86/PCI: VMD: Fix infinite loop executing irq's

We can't initialize the list head on deletion as this causes the node to
point to itself, which causes an infinite loop if vmd_irq() happens to be
servicing that node.

The list initialization was trying to fix a bug from multiple calls to
disable the same IRQ. Fix this instead by having the VMD driver track if
the interrupt is enabled.

[bhelgaas: changelog, add "Fixes"]
Fixes: 97e923063575 ("x86/PCI: VMD: Initialize list item in IRQ disable")
Reported-by: Grzegorz Koczot <grzegorz.koczot@intel.com>
Tested-by: Miroslaw Drost <miroslaw.drost@intel.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by Jon Derrick: <jonathan.derrick@intel.com>

um: Don't discard .text.exit section

Commit e41f501d3912 ("vmlinux.lds: account for destructor sections")
added '.text.exit' to EXIT_TEXT which is discarded at link time by default.
This breaks compilation of UML:
     `.text.exit' referenced in section `.fini_array' of
     /usr/lib/gcc/x86_64-linux-gnu/6/../../../x86_64-linux-gnu/libc.a(sdlerror.o):
     defined in discarded section `.text.exit' of
     /usr/lib/gcc/x86_64-linux-gnu/6/../../../x86_64-linux-gnu/libc.a(sdlerror.o)

Apparently UML doesn't want to discard exit text, so let's place all EXIT_TEXT
sections in .exit.text.

Fixes: e41f501d3912 ("vmlinux.lds: account for destructor sections")
Reported-by: Stefan Traby <stefan@hello-penguin.com>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: <stable@vger.kernel.org>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Fix xattr generic handler usage

UBIFS uses full names to work with xattrs, therefore we have to use
xattr_full_name() to obtain the xattr prefix as string.

Cc: <stable@vger.kernel.org>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Fixes: 2b88fc21ca ("ubifs: Switch to generic xattr handlers")
Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Tested-by: Dongsheng Yang <dongsheng081251@gmail.com>

ubifs: Fix assertion in layout_in_gaps()

An assertion in layout_in_gaps() verifies that the gap_lebs pointer is
below the maximum bound. When computing this maximum bound the idx_lebs
count is multiplied by sizeof(int), while C pointers arithmetic does take
into account the size of the pointed elements implicitly already. Remove
the multiplication to fix the assertion.

Fixes: 1e51764a3c2ac05a ("UBIFS: add new flash file system")
Cc: <stable@vger.kernel.org>
Signed-off-by: Vincent Stehlé <vincent.stehle@intel.com>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Merge tag 'usercopy-v4.8-rc4' of git://git./linux/kernel/git/kees/linux

Pull hardened usercopy fixes from Kees Cook:
- avoid signed math problems on unexpected compilers
- avoid false positives at very end of kernel text range checks

* tag 'usercopy-v4.8-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
usercopy: fix overlap check for kernel text
usercopy: avoid potentially undefined behavior in pointer math

Merge branch 'linus' of git://git./linux/kernel/git/herbert/crypto-2.6

Pull crypto fixes from Herbert Xu:
"This fixes a number of memory corruption bugs in the newly added
  sha256-mb/sha256-mb code"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: sha512-mb - fix ctx pointer
  crypto: sha256-mb - fix ctx pointer and digest copy

vhost/scsi: fix reuse of &vq->iov[out] in response

The address of the iovec &vq->iov[out] is not guaranteed to contain the scsi
command's response iovec throughout the lifetime of the command. Rather, it
is more likely to contain an iovec from an immediately following command
after looping back around to vhost_get_vq_desc(). Pass along the iovec
entirely instead.

Fixes: 79c14141a487 ("vhost/scsi: Convert completion path to use copy_to_iter")
Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

usercopy: fix overlap check for kernel text

When running with a local patch which moves the '_stext' symbol to the
very beginning of the kernel text area, I got the following panic with
CONFIG_HARDENED_USERCOPY:

  usercopy: kernel memory exposure attempt detected from ffff88103dfff000 (<linear kernel text>) (4096 bytes)
  ------------[ cut here ]------------
  kernel BUG at mm/usercopy.c:79!
  invalid opcode: 0000 [#1] SMP
  ...
  CPU: 0 PID: 4800 Comm: cp Not tainted 4.8.0-rc3.after+ #1
  Hardware name: Dell Inc. PowerEdge R720/0X3D66, BIOS 2.5.4 01/22/2016
  task: ffff880817444140 task.stack: ffff880816274000
  RIP: 0010:[<ffffffff8121c796>] __check_object_size+0x76/0x413
  RSP: 0018:ffff880816277c40 EFLAGS: 00010246
  RAX: 000000000000006b RBX: ffff88103dfff000 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: ffff88081f80dfa8 RDI: ffff88081f80dfa8
  RBP: ffff880816277c90 R08: 000000000000054c R09: 0000000000000000
  R10: 0000000000000005 R11: 0000000000000006 R12: 0000000000001000
  R13: ffff88103e000000 R14: ffff88103dffffff R15: 0000000000000001
  FS:  00007fb9d1750800(0000) GS:ffff88081f800000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00000000021d2000 CR3: 000000081a08f000 CR4: 00000000001406f0
  Stack:
   ffff880816277cc8 0000000000010000 000000043de07000 0000000000000000
   0000000000001000 ffff880816277e60 0000000000001000 ffff880816277e28
   000000000000c000 0000000000001000 ffff880816277ce8 ffffffff8136c3a6
  Call Trace:
   [<ffffffff8136c3a6>] copy_page_to_iter_iovec+0xa6/0x1c0
   [<ffffffff8136e766>] copy_page_to_iter+0x16/0x90
   [<ffffffff811970e3>] generic_file_read_iter+0x3e3/0x7c0
   [<ffffffffa06a738d>] ? xfs_file_buffered_aio_write+0xad/0x260 [xfs]
   [<ffffffff816e6262>] ? down_read+0x12/0x40
   [<ffffffffa06a61b1>] xfs_file_buffered_aio_read+0x51/0xc0 [xfs]
   [<ffffffffa06a6692>] xfs_file_read_iter+0x62/0xb0 [xfs]
   [<ffffffff812224cf>] __vfs_read+0xdf/0x130
   [<ffffffff81222c9e>] vfs_read+0x8e/0x140
   [<ffffffff81224195>] SyS_read+0x55/0xc0
   [<ffffffff81003a47>] do_syscall_64+0x67/0x160
   [<ffffffff816e8421>] entry_SYSCALL64_slow_path+0x25/0x25
  RIP: 0033:[<00007fb9d0c33c00>] 0x7fb9d0c33c00
  RSP: 002b:00007ffc9c262f28 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
  RAX: ffffffffffffffda RBX: fffffffffff8ffff RCX: 00007fb9d0c33c00
  RDX: 0000000000010000 RSI: 00000000021c3000 RDI: 0000000000000004
  RBP: 00000000021c3000 R08: 0000000000000000 R09: 00007ffc9c264d6c
  R10: 00007ffc9c262c50 R11: 0000000000000246 R12: 0000000000010000
  R13: 00007ffc9c2630b0 R14: 0000000000000004 R15: 0000000000010000
  Code: 81 48 0f 44 d0 48 c7 c6 90 4d a3 81 48 c7 c0 bb b3 a2 81 48 0f 44 f0 4d 89 e1 48 89 d9 48 c7 c7 68 16 a3 81 31 c0 e8 f4 57 f7 ff <0f> 0b 48 8d 90 00 40 00 00 48 39 d3 0f 83 22 01 00 00 48 39 c3
  RIP  [<ffffffff8121c796>] __check_object_size+0x76/0x413
   RSP <ffff880816277c40>

The checked object's range [ffff88103dfff000, ffff88103e000000) is
valid, so there shouldn't have been a BUG.  The hardened usercopy code
got confused because the range's ending address is the same as the
kernel's text starting address at 0xffff88103e000000.  The overlap check
is slightly off.

Fixes: f5509cc18daa ("mm: Hardened usercopy")
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>

usercopy: avoid potentially undefined behavior in pointer math

check_bogus_address() checked for pointer overflow using this expression,
where 'ptr' has type 'const void *':

ptr + n < ptr

Since pointer wraparound is undefined behavior, gcc at -O2 by default
treats it like the following, which would not behave as intended:

(long)n < 0

Fortunately, this doesn't currently happen for kernel code because kernel
code is compiled with -fno-strict-overflow. But the expression should be
fixed anyway to use well-defined integer arithmetic, since it could be
treated differently by different compilers in the future or could be
reported by tools checking for undefined behavior.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>

Merge tag 'arc-4.8-rc4-fixes' of git://git./linux/kernel/git/vgupta/arc

Pull ARC fixes from Vineet Gupta:

- support for Syscall ABI v4 with upstream gcc 6.x

- lockdep fix (Daniel Mentz)

- gdb register clobber (Liav Rehana)

- couple of missing exports for modules

- other fixes here and there

* tag 'arc-4.8-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: export __udivdi3 for modules
  ARC: mm: fix build breakage with STRICT_MM_TYPECHECKS
  ARC: export kmap
  ARC: Support syscall ABI v4
  ARC: use correct offset in pt_regs for saving/restoring user mode r25
  ARC: Elide redundant setup of DMA callbacks
  ARC: Call trace_hardirqs_on() before enabling irqs

Merge tag 'gpio-v4.8-2' of git://git./linux/kernel/git/linusw/linux-gpio

Pull GPIO fixes from Linus Walleij:
"Here are a few GPIO fixes for v4.8.

  I was expecting some fallout from the new chardev rework but nothing
  like that turned up att all.  Instead a Kconfig confusion that I think
  I have finally nailed, then some ordinary driver noise and trivia.

  This fixes a Kconfig issue with UM: when I made GPIOLIB available to
  all archs, that included UM, but the OF part of GPIOLIB requires
  HAS_IOMEM, so we add HAS_IOMEM as a dependency to OF_GPIO.

  This in turn exposed the fact that a few GPIO drivers were implicitly
  assuming OF_GPIO as their dependency but instead depended on OF alone
  (the typical problem being a pointer inside gpio_chip not existing
  unless OF_GPIO is selected) and then UM would fail to compile with
  these drivers instead.  Then I lost patience and made any GPIO driver
  depending on just OF depend on OF_GPIO instead, that is certainly what
  they meant and the only thing that makes sense anyway.  GPIO with just
  OF but !OF_GPIO does not make sense.

  Also a fix for the max730x driver data pointer, and a minor comment
  fix for the GPIO tools"

* tag 'gpio-v4.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: make any OF dependent driver depend on OF_GPIO
  gpio: Fix OF build problem on UM
  gpio: max730x: set gpiochip data pointer before using it
  tools/gpio: fix gpio-event-mon header comment

Input: ads7846 - remove redundant regulator_disable call

ADS7846 regulator is disabled twice in a row in ads7846_remove(). Valid
one is in ads7846_disable().

Removing the ads7846 module causes warning about unbalanced disables.

  ...
  WARNING: CPU: 0 PID: 29269 at drivers/regulator/core.c:2251 _regulator_disable+0xf8/0x130
  unbalanced disables for vads7846
  CPU: 0 PID: 29269 Comm: rmmod Tainted: G      D W       4.7.0+ #3
  Hardware name: HTC Magician
  ...
    show_stack+0x10/0x14
    __warn+0xd8/0x100
    warn_slowpath_fmt+0x38/0x48
    _regulator_disable+0xf8/0x130
    regulator_disable+0x34/0x60
    ads7846_remove+0x58/0xd4 [ads7846]
    spi_drv_remove+0x1c/0x34
    __device_release_driver+0x84/0x114
    driver_detach+0x8c/0x90
    bus_remove_driver+0x5c/0xc8
    SyS_delete_module+0x1a0/0x238
    ret_fast_syscall+0x0/0x38

Signed-off-by: Petr Cvek <petr.cvek@tul.cz>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: synaptics-rmi4 - fix register descriptor subpacket map construction

The map_offset variable is specific to the register and needs to be reset
in the loop. Otherwise, subsequent register's subpacket maps will have
their bits set at the wrong index.

Signed-off-by: Andrew Duggan <aduggan@synaptics.com>
Tested-by: Nitin Chaudhary <nitinchaudhary1289@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: tegra-kbc - fix inverted reset logic

Commit fe6b0dfaba68 ("Input: tegra-kbc - use reset framework")
accidentally converted _deassert to _assert, so there is no code
to wake up this hardware.

Fixes: fe6b0dfaba68 ("Input: tegra-kbc - use reset framework")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: silead - use devm_gpiod_get

The silead code is using devm_foo for everything (and does not free
any resources). Except that it is using gpiod_get instead of
devm_gpiod_get (but is not freeing the gpio_desc), change this
to use devm_gpiod_get so that the gpio will be properly released.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

bdev: fix NULL pointer dereference

I got this:

    kasan: GPF could be caused by NULL-ptr deref or user memory access
    general protection fault: 0000 [#1] PREEMPT SMP KASAN
    Dumping ftrace buffer:
       (ftrace buffer empty)
    CPU: 0 PID: 5505 Comm: syz-executor Not tainted 4.8.0-rc2+ #161
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
    task: ffff880113415940 task.stack: ffff880118350000
    RIP: 0010:[<ffffffff8172cb32>]  [<ffffffff8172cb32>] bd_mount+0x52/0xa0
    RSP: 0018:ffff880118357ca0  EFLAGS: 00010207
    RAX: dffffc0000000000 RBX: ffffffffffffffff RCX: ffffc90000bb6000
    RDX: 0000000000000018 RSI: ffffffff846d6b20 RDI: 00000000000000c7
    RBP: ffff880118357cb0 R08: ffff880115967c68 R09: 0000000000000000
    R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801188211e8
    R13: ffffffff847baa20 R14: ffff8801139cb000 R15: 0000000000000080
    FS:  00007fa3ff6c0700(0000) GS:ffff88011aa00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 00007fc1d8cc7e78 CR3: 0000000109f20000 CR4: 00000000000006f0
    DR0: 000000000000001e DR1: 000000000000001e DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
    Stack:
     ffff880112cfd6c0 ffff8801188211e8 ffff880118357cf0 ffffffff8167f207
     ffffffff816d7a1e ffff880112a413c0 ffffffff847baa20 ffff8801188211e8
     0000000000000080 ffff880112cfd6c0 ffff880118357d38 ffffffff816dce0a
    Call Trace:
     [<ffffffff8167f207>] mount_fs+0x97/0x2e0
     [<ffffffff816d7a1e>] ? alloc_vfsmnt+0x55e/0x760
     [<ffffffff816dce0a>] vfs_kern_mount+0x7a/0x300
     [<ffffffff83c3247c>] ? _raw_read_unlock+0x2c/0x50
     [<ffffffff816dfc87>] do_mount+0x3d7/0x2730
     [<ffffffff81235fd4>] ? trace_do_page_fault+0x1f4/0x3a0
     [<ffffffff816df8b0>] ? copy_mount_string+0x40/0x40
     [<ffffffff8161ea81>] ? memset+0x31/0x40
     [<ffffffff816df73e>] ? copy_mount_options+0x1ee/0x320
     [<ffffffff816e2a02>] SyS_mount+0xb2/0x120
     [<ffffffff816e2950>] ? copy_mnt_ns+0x970/0x970
     [<ffffffff81005524>] do_syscall_64+0x1c4/0x4e0
     [<ffffffff83c3282a>] entry_SYSCALL64_slow_path+0x25/0x25
    Code: 83 e8 63 1b fc ff 48 85 c0 48 89 c3 74 4c e8 56 35 d1 ff 48 8d bb c8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 36 4c 8b a3 c8 00 00 00 48 b8 00 00 00 00 00 fc
    RIP  [<ffffffff8172cb32>] bd_mount+0x52/0xa0
     RSP <ffff880118357ca0>
    ---[ end trace 13690ad962168b98 ]---

mount_pseudo() returns ERR_PTR(), not NULL, on error.

Fixes: 3684aa7099e0 ("block-dev: enable writeback cgroup support")
Cc: Shaohua Li <shli@fb.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@fb.com>
Cc: stable@vger.kernel.org
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Merge branch 'for-joerg/arm-smmu/fixes' of git://git./linux/kernel/git/will/linux into iommu/fixes

Linux 4.8-rc3

Merge branch 'parisc-4.8-2' of git://git./linux/kernel/git/deller/parisc-linux

Pull two parisc fixes from Helge Deller:
"The first patch ensures that the high-res cr16 clocksource (which was
  added in kernel 4.7) gets choosen as default clocksource for parisc.

  The second patch moves the #define of EREFUSED down inside errno.h and
  thus unbreaks building the gccgo compiler"

* 'parisc-4.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Fix order of EREFUSED define in errno.h
  parisc: Fix automatic selection of cr16 clocksource

EDAC, skx_edac: Add EDAC driver for Skylake

This is an entirely new driver instead of yet another set of patches
to sb_edac.c because:

1) Mapping from PCI devices to socket/memory controller is significantly
   different. Skylake scatters devices on a socket across a number of
   PCI buses.
2) There is an extra level of interleaving via the "mcroute" register
   that would be a little messy to squeeze into the old driver.
3) Validation is getting too expensive. Changes to sb_edac need to
   be checked against Sandy Bridge, Ivy Bridge, Haswell, Broadwell and
   Knights Landing.

Acked-by: Aristeu Rozanski <aris@redhat.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parisc: Fix order of EREFUSED define in errno.h

When building gccgo in userspace, errno.h gets parsed and the go include file
sysinfo.go is generated.

Since EREFUSED is defined to the same value as ECONNREFUSED, and ECONNREFUSED
is defined later on in errno.h, this leads to go complaining that EREFUSED
isn't defined yet.

Fix this trivial problem by moving the define of EREFUSED down after
ECONNREFUSED in errno.h (and clean up the indenting while touching this line).

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org

parisc: Fix automatic selection of cr16 clocksource

Commit 54b66800907 (parisc: Add native high-resolution sched_clock()
implementation) added support to use the CPU-internal cr16 counters as reliable
clocksource with the help of HAVE_UNSTABLE_SCHED_CLOCK.

Sadly the commit missed to remove the hack which prevented cr16 to become the
default clocksource even on SMP systems.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # 4.7+

ARC: export __udivdi3 for modules

Some module using div_u64() was failing to link because the libgcc 64-bit
divide assist routine was not being exported for modules

Reported-by: avinashp@quantenna.com
Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

Merge branch 'v4.8-rc2-bcache-fixes' of https://bitbucket.org/ewheelerinc/linux into for-linus

Eric writes:

Please pull this bcache branch based on v4.8-rc2. These fix one
deadlock, one use blkdev_put() use counter, and one dmesg output with a
better pr_err() description.

Make the hardened user-copy code depend on having a hardened allocator

The kernel test robot reported a usercopy failure in the new hardened
sanity checks, due to a page-crossing copy of the FPU state into the
task structure.

This happened because the kernel test robot was testing with SLOB, which
doesn't actually do the required book-keeping for slab allocations, and
as a result the hardening code didn't realize that the task struct
allocation was one single allocation - and the sanity checks fail.

Since SLOB doesn't even claim to support hardening (and you really
shouldn't use it), the straightforward solution is to just make the
usercopy hardening code depend on the allocator supporting it.

Reported-by: kernel test robot <xiaolong.ye@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge branch 'i2c/for-current' of git://git./linux/kernel/git/wsa/linux

Pull i2c fixes from Wolfram Sang:
"I2C has some pretty standard driver bugfixes and one minor cleanup"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: meson: Use complete() instead of complete_all()
  i2c: brcmstb: Use complete() instead of complete_all()
  i2c: bcm-kona: Use complete() instead of complete_all()
  i2c: bcm-iproc: Use complete() instead of complete_all()
  i2c: at91: fix support of the "alternative command" feature
  i2c: ocores: add missed clk_disable_unprepare() on failure paths
  i2c: cros-ec-tunnel: Fix usage of cros_ec_cmd_xfer()
  i2c: mux: demux-pinctrl: properly roll back when adding adapter fails

ARC: mm: fix build breakage with STRICT_MM_TYPECHECKS

|  CC      mm/memory.o
| In file included from ../mm/memory.c:53:0:
| ../include/linux/pfn_t.h: In function ‘pfn_t_pte’:
| ../include/linux/pfn_t.h:78:2: error: conversion to non-scalar type requested
|  return pfn_pte(pfn_t_to_pfn(pfn), pgprot);

With STRICT_MM_TYPECHECKS pte_t is a struct and the offending code
forces a cast which ends up shifting a struct and hence the gcc warning.

Note that in recent past some of the arches (aarch64, s390) made
STRICT_MM_TYPECHECKS default, but we don't for ARC as this leads to slightly
worse generated code, given ARC ABI definition of returning structs
(which pte_t would become)

Quoting from ARC ABI...

  "Results of type struct are returned in a caller-supplied temporary
  variable whose address is passed in r0.
  For such functions, the arguments are shifted so that they are
  passed in r1 and up."

So
- struct to be returned would be allocated on stack requiring extra
   code at call sites
- callee updates stack memory to facilitate the return (vs. simple
   MOV into return reg r0)

Hence STRICT_MM_TYPECHECKS is not enabled by default for ARC

Cc: <stable@vger.kernel.org> #4.4+
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

ARC: export kmap

| MODPOST 7 modules
| ERROR: "kmap" [fs/ext2/ext2.ko] undefined!
| ../scripts/Makefile.modpost:91: recipe for target '__modpost' failed

Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

ARC: Support syscall ABI v4

The syscall ABI includes the gcc functional calling ABI since a syscall
implies userland caller and kernel callee.

The current gcc ABI (v3) for ARCv2 ISA required 64-bit data be passed in
even-odd register pairs, (potentially punching reg holes when passing such
values as args). This was partly driven by the fact that the double-word
LDD/STD instructions in ARCv2 expect the register alignment and thus gcc
forcing this avoids extra MOV at the cost of a few unused register (which we
have plenty anyways).

This however was rejected as part of upstreaming gcc port to HS. So the new
ABI v4 doesn't enforce the even-odd reg restriction.

Do note that for ARCompact ISA builds v3 and v4 are practically the same in
terms of gcc code generation.

In terms of change management, we infer the new ABI if gcc 6.x onwards
is used for building the kernel.

This also needs a stable backport to enable older kernels to work with
new tools/user-space

Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

ARC: use correct offset in pt_regs for saving/restoring user mode r25

User mode callee regs are explicitly collected before signal delivery or
breakpoint trap. r25 is special for kernel as it serves as task pointer,
so user mode value is clobbered very early. It is saved in pt_regs where
generally only scratch (aka caller saved) regs are saved.

The code to access the corresponding pt_regs location had a subtle bug as
it was using load/store with scaling of offset, whereas the offset was already
byte wise correct. So fix this by replacing LD.AS with a standard LD

Cc: <stable@vger.kernel.org>
Signed-off-by: Liav Rehana <liavr@mellanox.com>
Reviewed-by: Alexey Brodkin <abrodkin@synopsys.com>
[vgupta: rewrote title and commit log]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

Input: i8042 - set up shared ps2_cmd_mutex for AUX ports

The commit 4097461897df ("Input: i8042 - break load dependency ...")
correctly set up ps2_cmd_mutex pointer for the KBD port but forgot to do
the same for AUX port(s), which results in communication on KBD and AUX
ports to clash with each other.

Fixes: 4097461897df ("Input: i8042 - break load dependency ...")
Reported-by: Bruno Wolff III <bruno@wolff.to>
Tested-by: Bruno Wolff III <bruno@wolff.to>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Merge branch 'stable/for-jens-4.8-for-linus' of git://git./linux/kernel/git/konrad/xen into for-linus

Konrad writes:

Please git pull the following three fixes in to your 'for-linus' branch.
It is against 'for-linus' instead of 'for-4.8/drivers' because we had
some code in xen-blkfront go through the Xen tree (with your Ack). The
reason was that you 'for-4.8/drivers' was based on 4.7-rc2, and the
fixes needed to be against newer tag.

This branch fixes as we are exercising the multiqueue components more
aggressively.

Merge tag 'dm-4.8-fixes-2' of git://git./linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

- a stable fix for DM round robin multipath path selector to disable
   preemption before using this_cpu_ptr()

- a slight increase in DM crypt's mempool reserves to make swap ontop
   of DM crypt more performant

- a few DM raid fixes to issues found while testing changes that were
   merged in v4.8-rc1

* tag 'dm-4.8-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm raid: support raid0 with missing metadata devices
  dm raid: enhance attempt_restore_of_faulty_devices() to support more devices
  dm raid: fix restoring of failed devices regression
  dm raid: fix frozen recovery regression
  dm crypt: increase mempool reserve to better support swapping
  dm round robin: do not use this_cpu_ptr() without having preemption disabled

xen-blkfront: free resources if xlvbd_alloc_gendisk fails

Current code forgets to free resources in the failure path of
xlvbd_alloc_gendisk(), this patch fix it.

Signed-off-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

xen-blkfront: introduce blkif_set_queue_limits()

blk_mq_update_nr_hw_queues() reset all queue limits to default which it's
not as xen-blkfront expected, introducing blkif_set_queue_limits() to reset
limits with initial correct values.

Signed-off-by: Bob Liu <bob.liu@oracle.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

xen-blkfront: fix places not updated after introducing 64KB page granularity

Two places didn't get updated when 64KB page granularity was introduced,
this patch fix them.

Signed-off-by: Bob Liu <bob.liu@oracle.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

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

Pull SCSI fixes from James Bottomley:
"Six fairly small fixes.  The ipr, mpt3sas and ses ones all trigger
  oopses.  The megaraid one fixes an attach failure on io mapped only
  cards, the fcoe one is an obvious problem in the error path and the
  aacraid one is a theoretical security issue (ability to trick the
  kernel into a buffer overrun)"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  ses: Fix racy cleanup of /sys in remove_dev()
  mpt3sas: Fix resume on WarpDrive flash cards
  ipr: Fix sync scsi scan
  megaraid_sas: Fix probing cards without io port
  aacraid: Check size values after double-fetch from user
  fcoe: Use kfree_skb() instead of kfree()

Merge tag 'usb-4.8-rc3' of git://git./linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
"Here are a number of USB fixes for reported issues for your tree.

  The normal amount of gadget fixes, xhci fixes, new device ids, and a
  few other minor things.  All of them have been in linux-next for a
  while, the full details are in the shortlog below"

* tag 'usb-4.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (43 commits)
  xhci: don't dereference a xhci member after removing xhci
  usb: xhci: Fix panic if disconnect
  xhci: really enqueue zero length TRBs.
  xhci: always handle "Command Ring Stopped" events
  cdc-acm: fix wrong pipe type on rx interrupt xfers
  usb: misc: usbtest: add fix for driver hang
  usb: dwc3: gadget: stop processing on HWO set
  usb: dwc3: don't set last bit for ISOC endpoints
  usb: gadget: rndis: free response queue during REMOTE_NDIS_RESET_MSG
  usb: udc: core: fix error handling
  usb: gadget: fsl_qe_udc: off by one in setup_received_handle()
  usb/gadget: fix gadgetfs aio support.
  usb: gadget: composite: Fix return value in case of error
  usb: gadget: uvc: Fix return value in case of error
  usb: gadget: fix check in sync read from ep in gadgetfs
  usb: misc: usbtest: usbtest_do_ioctl may return positive integer
  usb: dwc3: fix missing platform_set_drvdata() in dwc3_of_simple_probe()
  usb: phy: omap-otg: Fix missing platform_set_drvdata() in omap_otg_probe()
  usb: gadget: configfs: add mutex lock before unregister gadget
  usb: gadget: u_ether: fix dereference after null check coverify warning
  ...

Merge tag 'xfs-iomap-for-linus-4.8-rc3' of git://git./linux/kernel/git/dgc/linux-xfs

Pull xfs and iomap fixes from Dave Chinner:
"Changes in this update:

  Regression fixes for XFS changes introduce in 4.8-rc1:
   - buffer IO accounting assert failure
   - ENOSPC block accounting reservation issue
   - DAX IO path page cache invalidation fix
   - rmapbt on-disk block count in agf
   - correct classification of rmap block type when updating AGFL.
   - iomap support for attribute fork mapping

  Regression fixes for iomap infrastructure in 4.8-rc1:
   - fiemap: honor FIEMAP_FLAG_SYNC
   - fiemap: implement FIEMAP_FLAG_XATTR support to fix XFS regression
   - make mark_page_accessed and pagefault_disable usage consistent with
     other IO paths"

* tag 'xfs-iomap-for-linus-4.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs:
  xfs: remove OWN_AG rmap when allocating a block from the AGFL
  xfs: (re-)implement FIEMAP_FLAG_XATTR
  xfs: simplify xfs_file_iomap_begin
  iomap: mark ->iomap_end as optional
  iomap: prepare iomap_fiemap for attribute mappings
  iomap: fiemap should honor the FIEMAP_FLAG_SYNC flag
  iomap: remove superflous pagefault_disable from iomap_write_actor
  iomap: remove superflous mark_page_accessed from iomap_write_actor
  xfs: store rmapbt block count in the AGF
  xfs: don't invalidate whole file on DAX read/write
  xfs: fix bogus space reservation in xfs_iomap_write_allocate
  xfs: don't assert fail on non-async buffers on ioacct decrement

Merge tag 'hwmon-for-linus-v4.8-rc2' of git://git./linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:
"Fix a bug in it87 driver and URLs in ftsteutates driver"

* tag 'hwmon-for-linus-v4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (ftsteutates) Correct ftp urls in driver documentation
hwmon: (it87) Features mask must be 32 bit wide

thermal: imx: fix a possible NULL dereference

of_match_device could return NULL, and so cause a NULL pointer
dereference later at line 472:
data->socdata = of_id->data;

For fixing this problem, we use of_device_get_match_data(), this will
simplify the code a little by using a standard function for
getting the match data.

Reported-by: coverity (CID 1324128)
Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

thermal: trivial: fix the typo

See the thermal code, the obvious typo from my editor.

Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

Thermal-INT3406: Delete owner assignment

The field "owner" is set by core. Thus delete an extra initialisation.

Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

thermal: cpu_cooling: Fix NULL dereference in cpufreq_state2power

Currently all CPU cooling devices share a
`struct thermal_cooling_device_ops` instance. The thermal core uses the
presence of functions in this struct to determine if a cooling device
has a power model (see cdev_is_power_actor). cpu_cooling.c adds the
power model functions to the shared struct when a device is registered
with a power model.

Therefore, if a CPU cooling device is registered using
[of_]cpufreq_power_cooling_register, _all_ devices will be determined to
have a power model, including any registered with
[of_]cpufreq_cooling_register. This can result in cpufreq_state2power
being called on a device where dyn_power_table is NULL.

With this commit, instead of having a shared thermal_cooling_device_ops
which is mutated, we have two versions: one with the power functions and
one without.

Signed-off-by: Brendan Jackman <brendan.jackman@arm.com>
Cc: Amit Daniel Kachhap <amit.kachhap@gmail.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Javi Merino <javi.merino@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

gpio: make any OF dependent driver depend on OF_GPIO

The drivers that depend on OF but not OF_GPIO are wreaking havoc
with the autobuilders for archs that have all requirements for
OF but not for OF_GPIO, particularly the UM (Usermode) arch does
not have iomem (NO_IOMEM) which result in configuring GPIOLIB but
without OF_GPIO which is wrong if the driver is using the .of_node
of the gpiochip, which only appears with OF_GPIO.

After a brief look at the drivers just depending on OF it seems
most if not all of them actually require stuff from gpiolib-of so
the dependency is wrong in the first place.

This simply patches the Kconfig so that all GPIO drivers using OF
depend on OF_GPIO rather than just OF.

Cc: Rabin Vincent <rabin@rab.in>
Cc: Pramod Gurav <pramod.gurav@smartplayin.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Phil Reid <preid@electromag.com.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

gpio: Fix OF build problem on UM

The UserMode (UM) Linux build was failing in gpiolib-of as it requires
ioremap()/iounmap() to exist, which is absent from UM. The non-existence
of IO memory is negatively defined as CONFIG_NO_IOMEM which means we
need to depend on HAS_IOMEM.

Cc: stable@vger.kernel.org
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

iommu/arm-smmu: Don't BUG() if we find aborting STEs with disable_bypass

The disable_bypass cmdline option changes the SMMUv3 driver to put down
faulting stream table entries by default, as opposed to bypassing
transactions from unconfigured devices.

In this mode of operation, it is entirely expected to see aborting
entries in the stream table if and when we come to installing a valid
translation, so don't trigger a BUG() as a result of misdiagnosing these
entries as stream table corruption.

Cc: <stable@vger.kernel.org>
Fixes: 48ec83bcbcf5 ("iommu/arm-smmu: Add initial driver support for ARM SMMUv3 devices")
Tested-by: Robin Murphy <robin.murphy@arm.com>
Reported-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

iommu/arm-smmu: Disable stalling faults for all endpoints

Enabling stalling faults can result in hardware deadlock on poorly
designed systems, particularly those with a PCI root complex upstream of
the SMMU.

Although it's not really Linux's job to save hardware integrators from
their own misfortune, it *is* our job to stop userspace (e.g. VFIO
clients) from hosing the system for everybody else, even if they might
already be required to have elevated privileges.

Given that the fault handling code currently executes entirely in IRQ
context, there is nothing that can sensibly be done to recover from
things like page faults anyway, so let's rip this code out for now and
avoid the potential for deadlock.

Cc: <stable@vger.kernel.org>
Fixes: 48ec83bcbcf5 ("iommu/arm-smmu: Add initial driver support for ARM SMMUv3 devices")
Reported-by: Matt Evans <matt.evans@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

iommu/arm-smmu: Fix CMDQ error handling

In the unlikely event of a global command queue error, the ARM SMMUv3
driver attempts to convert the problematic command into a CMD_SYNC and
resume the command queue. Unfortunately, this code is pretty badly
broken:

  1. It uses the index into the error string table as the CMDQ index,
     so we probably read the wrong entry out of the queue

  2. The arguments to queue_write are the wrong way round, so we end up
     writing from the queue onto the stack.

These happily cancel out, so the kernel is likely to stay alive, but
the command queue will probably fault again when we resume.

This patch fixes the error handling code to use the correct queue index
and write back the CMD_SYNC to the faulting entry.

Cc: <stable@vger.kernel.org>
Fixes: 48ec83bcbcf5 ("iommu/arm-smmu: Add initial driver support for ARM SMMUv3 devices")
Reported-by: Diwakar Subraveti <Diwakar.Subraveti@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

iommu/io-pgtable-arm-v7s: Fix attributes when splitting blocks

Due to the attribute bits being all over the place in the different
types of short-descriptor PTEs, when remapping an existing entry, e.g.
splitting a section into pages, we take the approach of decomposing
the PTE attributes back to the IOMMU API flags to start from scratch.

On inspection, though, the existing code seems to have got the read-only
bit backwards and ignored the XN bit. How embarrassing...

Fortunately the primary user so far, the Mediatek IOMMU, both never
splits blocks (because it only serves non-overlapping DMA API calls) and
also ignores permissions anyway, but let's put things right before any
future users trip up.

Cc: <stable@vger.kernel.org>
Fixes: e5fc9753b1a8 ("iommu/io-pgtable: Add ARMv7 short descriptor support")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

bcache: pr_err: more meaningful error message when nr_stripes is invalid

The original error was thought to be corruption, but was actually caused by:
make-bcache --data-offset N
where N was in bytes and should have been in sectors. While userspace
tools should be updated to check --data-offset beyond end of volume,
hopefully this will help others that might not have noticed the units.

Signed-off-by: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: Kent Overstreet <kent.overstreet@gmail.com>

bcache: RESERVE_PRIO is too small by one when prio_buckets() is a power of two.

This patch fixes a cachedev registration-time allocation deadlock.
This can deadlock on boot if your initrd auto-registeres bcache devices:

Allocator thread:
[  720.727614] INFO: task bcache_allocato:3833 blocked for more than 120 seconds.
[  720.732361]  [<ffffffff816eeac7>] schedule+0x37/0x90
[  720.732963]  [<ffffffffa05192b8>] bch_bucket_alloc+0x188/0x360 [bcache]
[  720.733538]  [<ffffffff810e6950>] ? prepare_to_wait_event+0xf0/0xf0
[  720.734137]  [<ffffffffa05302bd>] bch_prio_write+0x19d/0x340 [bcache]
[  720.734715]  [<ffffffffa05190bf>] bch_allocator_thread+0x3ff/0x470 [bcache]
[  720.735311]  [<ffffffff816ee41c>] ? __schedule+0x2dc/0x950
[  720.735884]  [<ffffffffa0518cc0>] ? invalidate_buckets+0x980/0x980 [bcache]

Registration thread:
[  720.710403] INFO: task bash:3531 blocked for more than 120 seconds.
[  720.715226]  [<ffffffff816eeac7>] schedule+0x37/0x90
[  720.715805]  [<ffffffffa05235cd>] __bch_btree_map_nodes+0x12d/0x150 [bcache]
[  720.716409]  [<ffffffffa0522d30>] ? bch_btree_insert_check_key+0x1c0/0x1c0 [bcache]
[  720.717008]  [<ffffffffa05236e4>] bch_btree_insert+0xf4/0x170 [bcache]
[  720.717586]  [<ffffffff810e6950>] ? prepare_to_wait_event+0xf0/0xf0
[  720.718191]  [<ffffffffa0527d9a>] bch_journal_replay+0x14a/0x290 [bcache]
[  720.718766]  [<ffffffff810cc90d>] ? ttwu_do_activate.constprop.94+0x5d/0x70
[  720.719369]  [<ffffffff810cf684>] ? try_to_wake_up+0x1d4/0x350
[  720.719968]  [<ffffffffa05317d0>] run_cache_set+0x580/0x8e0 [bcache]
[  720.720553]  [<ffffffffa053302e>] register_bcache+0xe2e/0x13b0 [bcache]
[  720.721153]  [<ffffffff81354cef>] kobj_attr_store+0xf/0x20
[  720.721730]  [<ffffffff812a2dad>] sysfs_kf_write+0x3d/0x50
[  720.722327]  [<ffffffff812a225a>] kernfs_fop_write+0x12a/0x180
[  720.722904]  [<ffffffff81225177>] __vfs_write+0x37/0x110
[  720.723503]  [<ffffffff81228048>] ? __sb_start_write+0x58/0x110
[  720.724100]  [<ffffffff812cedb3>] ? security_file_permission+0x23/0xa0
[  720.724675]  [<ffffffff812258a9>] vfs_write+0xa9/0x1b0
[  720.725275]  [<ffffffff8102479c>] ? do_audit_syscall_entry+0x6c/0x70
[  720.725849]  [<ffffffff81226755>] SyS_write+0x55/0xd0
[  720.726451]  [<ffffffff8106a390>] ? do_page_fault+0x30/0x80
[  720.727045]  [<ffffffff816f2cae>] system_call_fastpath+0x12/0x71

The fifo code in upstream bcache can't use the last element in the buffer,
which was the cause of the bug: if you asked for a power of two size,
it'd give you a fifo that could hold one less than what you asked for
rather than allocating a buffer twice as big.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: stable@vger.kernel.org

bcache: register_bcache(): call blkdev_put() when cache_alloc() fails

register_cache() is supposed to return an error string on error so that
register_bcache() will will blkdev_put and cleanup other user counters,
but it does not set 'char *err' when cache_alloc() fails (eg, due to
memory pressure) and thus register_bcache() performs no cleanup.

register_bcache() <----------\  <- no jump to err_close, no blkdev_put()
   |                         |
   +->register_cache()       |  <- fails to set char *err
         |                   |
         +->cache_alloc() ---/  <- returns error

This patch sets `char *err` for this failure case so that register_cache()
will cause register_bcache() to correctly jump to err_close and do
cleanup.  This was tested under OOM conditions that triggered the bug.

Signed-off-by: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: stable@vger.kernel.org

Merge tag 'drm-fixes-for-4.8-rc3-2' of git://people.freedesktop.org/~airlied/linux

Pull more drm fixes from Dave Airlie:
"Daniel pointed out I'd missed some i915 fixes, and I also found a
  single etnaviv fix I missed.

  So here they are"

* tag 'drm-fixes-for-4.8-rc3-2' of git://people.freedesktop.org/~airlied/linux:
  drm/etnaviv: take GPU lock later in the submit process
  drm/i915: Fix modeset handling during gpu reset, v5.
  drm/i915: fix aliasing_ppgtt leak
  drm/i915: fix WaInsertDummyPushConstPs
  drm/i915: Fix iboost setting for SKL Y/U DP DDI buffer translation entry 2
  drm/i915/gen9: Give one extra block per line for SKL plane WM calculations
  drm/i915: Acquire audio powerwell for HD-Audio registers
  drm/i915: Add missing rpm wakelock to GGTT pread
  drm/i915/fbc: FBC causes display flicker when VT-d is enabled on Skylake
  drm/i915: Clean up the extra RPM ref on CHV with i915.enable_rc6=0
  drm/i915: Program iboost settings for HDMI/DVI on SKL
  drm/i915: Fix iboost setting for DDI with 4 lanes on SKL
  drm/i915: Handle ENOSPC after failing to insert a mappable node
  drm/i915: Flush GT idle status upon reset