Revert "powerpc/eeh: Fix crash when adding a device in a slot with DDW"

This reverts commit 066f289835f09a3f744d6bac96f25e25d20b3ded which was
6a040ce72598159a74969a2d01ab0ba5ee6536b3 upstream.

This was not needed and is not suitable for 3.2.y.

Reported-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
btrfs: Init io_lock after cloning btrfs device struct

commit 1cba0cdf5e4dbcd9e5fa5b54d7a028e55e2ca057 upstream.

__btrfs_close_devices() clones btrfs device structs with
memcpy(). Some of the fields in the clone are reinitialized, but it's
missing to init io_lock. In mainline this goes unnoticed, but on RT it
leaves the plist pointing to the original about to be freed lock
struct.

Initialize io_lock after cloning, so no references to the original
struct are left.

Reported-and-tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
md: protect against crash upon fsync on ro array

commit bbfa57c0f2243a7c31fd248d22e9861a2802cad5 upstream.

If an fsync occurs on a read-only array, we need to send a
completion for the IO and may not increment the active IO count.
Otherwise, we hit a bug trace and can't stop the MD array anymore.

By advice of Christoph Hellwig we return success upon a flush
request but we return -EROFS for other writes.
We detect flush requests by checking if the bio has zero sectors.

This patch is suitable to any -stable kernel to which it applies.

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: NeilBrown <neilb@suse.de>
Signed-off-by: Sebastian Riemer <sebastian.riemer@profitbricks.com>
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Paul Menzel <paulepanter@users.sourceforge.net>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
NFS: Don't allow NFS silly-renamed files to be deleted, no signal

commit 5a7a613a47a715711b3f2d3322a0eac21d459166 upstream.

Commit 73ca100 broke the code that prevents the client from deleting
a silly renamed dentry.  This affected "delete on last close"
semantics as after that commit, nothing prevented removal of
silly-renamed files.  As a result, a process holding a file open
could easily get an ESTALE on the file in a directory where some
other process issued 'rm -rf some_dir_containing_the_file' twice.
Before the commit, any attempt at unlinking silly renamed files would
fail inside may_delete() with -EBUSY because of the
DCACHE_NFSFS_RENAMED flag.  The following testcase demonstrates
the problem:
  tail -f /nfsmnt/dir/file &
  rm -rf /nfsmnt/dir
  rm -rf /nfsmnt/dir
  # second removal does not fail, 'tail' process receives ESTALE

The problem with the above commit is that it unhashes the old and
new dentries from the lookup path, even in the normal case when
a signal is not encountered and it would have been safe to call
d_move.  Unfortunately the old dentry has the special
DCACHE_NFSFS_RENAMED flag set on it.  Unhashing has the
side-effect that future lookups call d_alloc(), allocating a new
dentry without the special flag for any silly-renamed files.  As a
result, subsequent calls to unlink silly renamed files do not fail
but allow the removal to go through.  This will result in ESTALE
errors for any other process doing operations on the file.

To fix this, go back to using d_move on success.
For the signal case, it's unclear what we may safely do beyond d_drop.

Reported-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
SUNRPC: Don't start the retransmission timer when out of socket space

commit a9a6b52ee1baa865283a91eb8d443ee91adfca56 upstream.

If the socket is full, we're better off just waiting until it empties,
or until the connection is broken. The reason why we generally don't
want to time out is that the call to xprt->ops->release_xprt() will
trigger a connection reset, which isn't helpful...

Let's make an exception for soft RPC calls, since they have to provide
timeout guarantees.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
storvsc: Initialize the sglist

commit 9d2696e658ef4f209955ddaa987d43f1a1bd81a1 upstream.

Properly initialize scatterlist before using it.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
dc395x: uninitialized variable in device_alloc()

commit 208afec4f3be8c51ad6eebe6611dd6d2ad2fa298 upstream.

This bug was introduced back in bitkeeper days in 2003.  We use
"dcb->dev_mode" before it has been initialized.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ARM: VFP: fix emulation of second VFP instruction

commit 5e4ba617c1b584b2e376f31a63bd4e734109318a upstream.

Martin Storsjö reports that the sequence:

        ee312ac1        vsub.f32        s4, s3, s2
        ee702ac0        vsub.f32        s5, s1, s0
        e59f0028        ldr             r0, [pc, #40]
        ee111a90        vmov            r1, s3

on Raspberry Pi (implementor 41 architecture 1 part 20 variant b rev 5)
where s3 is a denormal and s2 is zero results in incorrect behaviour -
the instruction "vsub.f32 s5, s1, s0" is not executed:

        VFP: bounce: trigger ee111a90 fpexc d0000780
        VFP: emulate: INST=0xee312ac1 SCR=0x00000000
        ...

As we can see, the instruction triggering the exception is the "vmov"
instruction, and we emulate the "vsub.f32 s4, s3, s2" but fail to
properly take account of the FPEXC_FP2V flag in FPEXC.  This is because
the test for the second instruction register being valid is bogus, and
will always skip emulation of the second instruction.

Reported-by: Martin Storsjö <martin@martin.st>
Tested-by: Martin Storsjö <martin@martin.st>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ARM: fix scheduling while atomic warning in alignment handling code

commit b255188f90e2bade1bd11a986dd1ca4861869f4d upstream.

Paolo Pisati reports that IPv6 triggers this warning:

BUG: scheduling while atomic: swapper/0/0/0x40000100
Modules linked in:
[<c001b1c4>] (unwind_backtrace+0x0/0xf0) from [<c0503c5c>] (__schedule_bug+0x48/0x5c)
[<c0503c5c>] (__schedule_bug+0x48/0x5c) from [<c0508608>] (__schedule+0x700/0x740)
[<c0508608>] (__schedule+0x700/0x740) from [<c007007c>] (__cond_resched+0x24/0x34)
[<c007007c>] (__cond_resched+0x24/0x34) from [<c05086dc>] (_cond_resched+0x3c/0x44)
[<c05086dc>] (_cond_resched+0x3c/0x44) from [<c0021f6c>] (do_alignment+0x178/0x78c)
[<c0021f6c>] (do_alignment+0x178/0x78c) from [<c00083e0>] (do_DataAbort+0x34/0x98)
[<c00083e0>] (do_DataAbort+0x34/0x98) from [<c0509a60>] (__dabt_svc+0x40/0x60)
Exception stack(0xc0763d70 to 0xc0763db8)
3d60:                                     e97e805e e97e806e 2c000000 11000000
3d80: ea86bb00 0000002c 00000011 e97e807e c076d2a8 e97e805e e97e806e 0000002c
3da0: 3d000000 c0763dbc c04b98fc c02a8490 00000113 ffffffff
[<c0509a60>] (__dabt_svc+0x40/0x60) from [<c02a8490>] (__csum_ipv6_magic+0x8/0xc8)

Fix this by using probe_kernel_address() stead of __get_user().

Reported-by: Paolo Pisati <p.pisati@gmail.com>
Tested-by: Paolo Pisati <p.pisati@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
md: fix two bugs when attempting to resize RAID0 array.

commit a64685399181780998281fe07309a94b25dd24c3 upstream.

You cannot resize a RAID0 array (in terms of making the devices
bigger), but the code doesn't entirely stop you.
So:

 disable setting of the available size on each device for
 RAID0 and Linear devices.  This must not change as doing so
 can change the effective layout of data.

 Make sure that the size that raid0_size() reports is accurate,
 but rounding devices sizes to chunk sizes.  As the device sizes
 cannot change now, this isn't so important, but it is best to be
 safe.

Without this change:
  mdadm --grow /dev/md0 -z max
  mdadm --grow /dev/md0 -Z max
  then read to the end of the array

can cause a BUG in a RAID0 array.

These bugs have been present ever since it became possible
to resize any device, which is a long time.  So the fix is
suitable for any -stable kerenl.

Signed-off-by: NeilBrown <neilb@suse.de>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
md: raid0: fix error return from create_stripe_zones.

commit 58ebb34c49fcfcaa029e4b1c1453d92583900f9a upstream.

Create_stripe_zones returns an error slightly differently to
raid0_run and to raid0_takeover_*.

The error returned used by the second was wrong and an error would
result in mddev->private being set to NULL and sooner or later a
crash.

So never return NULL, return ERR_PTR(err), not NULL from
create_stripe_zones.

This bug has been present since 2.6.35 so the fix is suitable
for any kernel since then.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
proc connector: reject unprivileged listener bumps

commit e70ab977991964a5a7ad1182799451d067e62669 upstream.

While PROC_CN_MCAST_LISTEN/IGNORE is entirely advisory, it was possible
for an unprivileged user to turn off notifications for all listeners by
sending PROC_CN_MCAST_IGNORE. Instead, require the same privileges as
required for a multicast bind.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Matt Helsley <matthltc@us.ibm.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Acked-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ath9k: fix RSSI dummy marker value

commit a3d63cadbad97671d740a9698acc2c95d1ca6e79 upstream.

RSSI is being stored internally as s8 in several places. The indication
of an unset RSSI value, ATH_RSSI_DUMMY_MARKER, was supposed to have been
set to 127, but ended up being set to 0x127 because of a code cleanup
mistake. This could lead to invalid signal strength values in a few
places.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ath9k_htc: fix signal strength handling issues

commit 838f427955dcfd16858b0108ce29029da0d56a4e upstream.

The ath9k commit 2ef167557c0a26c88162ecffb017bfcc51eb7b29
(ath9k: fix signal strength reporting issues) fixed an issue where the
reported per-frame signal strength reported to mac80211 was being
overwritten with an internal average. The same issue is also present
in ath9k_htc.
In addition to preventing the driver from overwriting the value, this
commit also ensures that the internal average (which is used for ANI)
only tracks beacons of the AP that we're connected to.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2: use compare_ether_addr() instead of
 ether_addr_equal(), with opposite sense]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
mwifiex: correct sleep delay counter

commit 3e7a4ff7c5b6423ddb644df9c41b8b6d2fb79d30 upstream.

Maximum delay for waking up card is 50 ms. Because of typo in
counter, this delay goes to 500ms. This patch fixes the bug.

Signed-off-by: Avinash Patil <patila@marvell.com>
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Yogesh Ashok Powar <yogeshp@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
cifs: ensure that cifs_get_root() only traverses directories

commit ce2ac52105aa663056dfc17966ebed1bf93e6e64 upstream.

Kjell Braden reported this oops:

[  833.211970] BUG: unable to handle kernel NULL pointer dereference at           (null)
[  833.212816] IP: [<          (null)>]           (null)
[  833.213280] PGD 1b9b2067 PUD e9f7067 PMD 0
[  833.213874] Oops: 0010 [#1] SMP
[  833.214344] CPU 0
[  833.214458] Modules linked in: des_generic md4 nls_utf8 cifs vboxvideo drm snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq bnep rfcomm snd_timer bluetooth snd_seq_device ppdev snd vboxguest parport_pc joydev mac_hid soundcore snd_page_alloc psmouse i2c_piix4 serio_raw lp parport usbhid hid e1000
[  833.215629]
[  833.215629] Pid: 1752, comm: mount.cifs Not tainted 3.0.0-rc7-bisectcifs-fec11dd9a0+ #18 innotek GmbH VirtualBox/VirtualBox
[  833.215629] RIP: 0010:[<0000000000000000>]  [<          (null)>]           (null)
[  833.215629] RSP: 0018:ffff8800119c9c50  EFLAGS: 00010282
[  833.215629] RAX: ffffffffa02186c0 RBX: ffff88000c427780 RCX: 0000000000000000
[  833.215629] RDX: 0000000000000000 RSI: ffff88000c427780 RDI: ffff88000c4362e8
[  833.215629] RBP: ffff8800119c9c88 R08: ffff88001fc15e30 R09: 00000000d69515c7
[  833.215629] R10: ffffffffa0201972 R11: ffff88000e8f6a28 R12: ffff88000c4362e8
[  833.215629] R13: 0000000000000000 R14: 0000000000000000 R15: ffff88001181aaa6
[  833.215629] FS:  00007f2986171700(0000) GS:ffff88001fc00000(0000) knlGS:0000000000000000
[  833.215629] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  833.215629] CR2: 0000000000000000 CR3: 000000001b982000 CR4: 00000000000006f0
[  833.215629] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  833.215629] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  833.215629] Process mount.cifs (pid: 1752, threadinfo ffff8800119c8000, task ffff88001c1c16f0)
[  833.215629] Stack:
[  833.215629]  ffffffff8116a9b5 ffff8800119c9c88 ffffffff81178075 0000000000000286
[  833.215629]  0000000000000000 ffff88000c4276c0 ffff8800119c9ce8 ffff8800119c9cc8
[  833.215629]  ffffffff8116b06e ffff88001bc6fc00 ffff88000c4276c0 ffff88000c4276c0
[  833.215629] Call Trace:
[  833.215629]  [<ffffffff8116a9b5>] ? d_alloc_and_lookup+0x45/0x90
[  833.215629]  [<ffffffff81178075>] ? d_lookup+0x35/0x60
[  833.215629]  [<ffffffff8116b06e>] __lookup_hash.part.14+0x9e/0xc0
[  833.215629]  [<ffffffff8116b1d6>] lookup_one_len+0x146/0x1e0
[  833.215629]  [<ffffffff815e4f7e>] ? _raw_spin_lock+0xe/0x20
[  833.215629]  [<ffffffffa01eef0d>] cifs_do_mount+0x26d/0x500 [cifs]
[  833.215629]  [<ffffffff81163bd3>] mount_fs+0x43/0x1b0
[  833.215629]  [<ffffffff8117d41a>] vfs_kern_mount+0x6a/0xd0
[  833.215629]  [<ffffffff8117e584>] do_kern_mount+0x54/0x110
[  833.215629]  [<ffffffff8117fdc2>] do_mount+0x262/0x840
[  833.215629]  [<ffffffff81108a0e>] ? __get_free_pages+0xe/0x50
[  833.215629]  [<ffffffff8117f9ca>] ? copy_mount_options+0x3a/0x180
[  833.215629]  [<ffffffff8118075d>] sys_mount+0x8d/0xe0
[  833.215629]  [<ffffffff815ece82>] system_call_fastpath+0x16/0x1b
[  833.215629] Code:  Bad RIP value.
[  833.215629] RIP  [<          (null)>]           (null)
[  833.215629]  RSP <ffff8800119c9c50>
[  833.215629] CR2: 0000000000000000
[  833.238525] ---[ end trace ec00758b8d44f529 ]---

When walking down the path on the server, it's possible to hit a
symlink. The path walking code assumes that the caller will handle that
situation properly, but cifs_get_root() isn't set up for it. This patch
prevents the oops by simply returning an error.

A better solution would be to try and chase the symlinks here, but that's
fairly complicated to handle.

Fixes:

    https://bugzilla.kernel.org/show_bug.cgi?id=53221

Reported-and-tested-by: Kjell Braden <afflux@pentabarf.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
xen/pci: We don't do multiple MSI's.

commit 884ac2978a295b7df3c4a686d3bff6932bbbb460 upstream.

There is no hypercall to setup multiple MSI per PCI device.
As such with these two new commits:
-  08261d87f7d1b6253ab3223756625a5c74532293
   PCI/MSI: Enable multiple MSIs with pci_enable_msi_block_auto()
- 5ca72c4f7c412c2002363218901eba5516c476b1
   AHCI: Support multiple MSIs

we would call the PHYSDEVOP_map_pirq 'nvec' times with the same
contents of the PCI device. Sander discovered that we would get
the same PIRQ value 'nvec' times and return said values to the
caller. That of course meant that the device was configured only
with one MSI and AHCI would fail with:

ahci 0000:00:11.0: version 3.0
xen: registering gsi 19 triggering 0 polarity 1
xen: --> pirq=19 -> irq=19 (gsi=19)
(XEN) [2013-02-27 19:43:07] IOAPIC[0]: Set PCI routing entry (6-19 -> 0x99 -> IRQ 19 Mode:1 Active:1)
ahci 0000:00:11.0: AHCI 0001.0200 32 slots 4 ports 6 Gbps 0xf impl SATA mode
ahci 0000:00:11.0: flags: 64bit ncq sntf ilck pm led clo pmp pio slum part
ahci: probe of 0000:00:11.0 failed with error -22

That is b/c in ahci_host_activate the second call to
devm_request_threaded_irq  would return -EINVAL as we passed in
(on the second run) an IRQ that was never initialized.

Reported-and-Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
dm: fix truncated status strings

commit fd7c092e711ebab55b2688d3859d95dfd0301f73 upstream.

Avoid returning a truncated table or status string instead of setting
the DM_BUFFER_FULL_FLAG when the last target of a table fills the
buffer.

When processing a table or status request, the function retrieve_status
calls ti->type->status. If ti->type->status returns non-zero,
retrieve_status assumes that the buffer overflowed and sets
DM_BUFFER_FULL_FLAG.

However, targets don't return non-zero values from their status method
on overflow. Most targets returns always zero.

If a buffer overflow happens in a target that is not the last in the
table, it gets noticed during the next iteration of the loop in
retrieve_status; but if a buffer overflow happens in the last target, it
goes unnoticed and erroneously truncated data is returned.

In the current code, the targets behave in the following way:
* dm-crypt returns -ENOMEM if there is not enough space to store the
  key, but it returns 0 on all other overflows.
* dm-thin returns errors from the status method if a disk error happened.
  This is incorrect because retrieve_status doesn't check the error
  code, it assumes that all non-zero values mean buffer overflow.
* all the other targets always return 0.

This patch changes the ti->type->status function to return void (because
most targets don't use the return code). Overflow is detected in
retrieve_status: if the status method fills up the remaining space
completely, it is assumed that buffer overflow happened.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
[bwh: Backported to 3.2:
 - Adjust context
 - dm_status_fn doesn't take a status_flags parameter
 - Bump the last component of each current version (verified not to
   match any version used in mainline)
 - Drop changes to dm-verity]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
dm snapshot: add missing module aliases

commit 23cb21092eb9dcec9d3604b68d95192b79915890 upstream.

Add module aliases so that autoloading works correctly if the user
tries to activate "snapshot-origin" or "snapshot-merge" targets.

Reference: https://bugzilla.redhat.com/889973

Reported-by: Chao Yang <chyang@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
drm/i915: Don't clobber crtc->fb when queue_flip fails

commit 4a35f83b2b7c6aae3fc0d1c4554fdc99dc33ad07 upstream.

Restore crtc->fb to the old framebuffer if queue_flip fails.

While at it, kill the pointless intel_fb temp variable.

v2: Update crtc->fb before queue_flip and restore it back
    after a failure.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reported-and-Tested-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>