Shame on me!  Commit b1dea800 "tmpfs: fix race between umount and
writepage" fixed the advertized race, but introduced another: as even
its comment makes clear, we cannot safely rely on a peek at list_empty()
while holding no lock - until info->swapped is set, shmem_unuse_inode()
may delete any formerly-swapped inode from the shmem_swaplist, which
in this case would leave a swap area impossible to swapoff.

Although I don't relish taking the mutex every time, I don't care much
for the alternatives either; and at least the peek at list_empty() in
shmem_evict_inode() (a hotter path since most inodes would never have
been swapped) remains safe, because we already truncated the whole file.
Signed-off-by: NHugh Dickins <hughd@google.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* fbmem:
  Further fbcon sanity checking
  fbmem: fix remove_conflicting_framebuffers races

This reverts commit 270dac35.

The commits causes command timeouts on AC plug/unplug.  It isn't yet
clear why.  As the commit was for a single rather obscure controller,
revert the change for now.

The problem was reported and bisected by Gu Rui in bug#34692.

 https://bugzilla.kernel.org/show_bug.cgi?id=34692

Also, reported by Rafael and Michael in the following thread.

 http://thread.gmane.org/gmane.linux.kernel/1138771Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NGu Rui <chaos.proton@gmail.com>
Reported-by: NRafael J. Wysocki <rjw@sisk.pl>
Reported-by: NMichael Leun <lkml20100708@newton.leun.net>
Cc: Jian Peng <jipeng2005@gmail.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This moves the

    if (num_registered_fb == FB_MAX)
            return -ENXIO;

check _AFTER_ the call to do_remove_conflicting_framebuffers() as this
would (now in a safe way) allow a native driver to replace the
conflicting one even if all slots in registered_fb[] are taken.

This also prevents unregistering a framebuffer that is no longer
registered (vga16f will unregister at module unload time even if the
frame buffer had been unregistered earlier due to being found
conflicting).
Signed-off-by: NBruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When a register_framebuffer() call results in us removing old
conflicting framebuffers, the new registration_lock doesn't protect that
situation.  And we can't just add the same locking to the function,
because these functions call each other: register_framebuffer() calls
remove_conflicting_framebuffers, which in turn calls
unregister_framebuffer for any conflicting entry.

In order to fix it, this just creates wrapper functions around all three
functions and makes the versions that actually do the work be called
"do_xxx()", leaving just the wrapper that gets the lock and calls the
worker function.

So the rule becomes simply that "do_xxxx()" has to be called with the
lock held, and now do_register_framebuffer() can just call
do_remove_conflicting_framebuffers(), and that in turn can call
_do_unregister_framebuffer(), and there is no deadlock, and we can hold
the registration lock over the whole sequence, fixing the races.

It also makes error cases simpler, and fixes one situation where we
would return from unregister_framebuffer() without releasing the lock,
pointed out by Bruno Prémont.
Tested-by: NBruno Prémont <bonbons@linux-vserver.org>
Tested-by: NAnca Emanuel <anca.emanuel@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mattst88/alpha-2.6:
  alpha: Wire up syscalls new to 2.6.39
  alpha: convert to clocksource_register_hz

Wire up the syscalls:
   name_to_handle_at
   open_by_handle_at
   clock_adjtime
   syncfs
and adjust some whitespace in the neighbourhood to align commments.
Signed-off-by: NMichael Cree <mcree@orcon.net.nz>
Signed-off-by: NMatt Turner <mattst88@gmail.com>

Converts alpha to use clocksource_register_hz.
Signed-off-by: NJohn Stultz <johnstul@us.ibm.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
CC: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMatt Turner <mattst88@gmail.com>

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
  bridge: fix forwarding of IPv6
  bonding,llc: Fix structure sizeof incompatibility for some PDUs
  ipv6: restore correct ECN handling on TCP xmit
  ne-h8300: Fix regression caused during net_device_ops conversion
  hydra: Fix regression caused during net_device_ops conversion
  zorro8390: Fix regression caused during net_device_ops conversion
  sfc: Always map MCDI shared memory as uncacheable
  ehea: Fix memory hotplug oops
  libertas: fix cmdpendingq locking
  iwlegacy: fix IBSS mode crashes
  ath9k: Fix a warning due to a queued work during S3 state
  mac80211: don't start the dynamic ps timer if not associated

* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  NFSv4.1: Ensure that layoutget uses the correct gfp modes
  NFSv4.1: remove pnfs_layout_hdr from pnfs_destroy_all_layouts tmp_list
  NFSv41: Resend on NFS4ERR_RETRY_UNCACHED_REP

The commit 6b1e960f
    bridge: Reset IPCB when entering IP stack on NF_FORWARD
broke forwarding of IPV6 packets in bridge because it would
call bp_parse_ip_options with an IPV6 packet.
Reported-by: NNoah Meyerhans <noahm@debian.org>
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Reviewed-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

My Q67 / i7-2600 box has rev09 Sandy Bridge graphics.  It hangs
instantly when GNOME loads and it hangs so hard the reset button
doesn't work.  Setting i915.semaphore=0 fixes it.

Semaphores were disabled in a1656b90 ("drm/i915: Disable GPU
semaphores by default") in 2.6.38 but were then re-enabled (by mistake?)
by the merge 47ae63e0 ("Merge branch 'drm-intel-fixes' into
drm-intel-next").

(It's worth noting that the offending change is i915_drv.c, which was
not marked as a conflict - although a 'git show --cc' on the merge does
show that neither parent had it set to 1)
Signed-off-by: NAndy Lutomirski <luto@mit.edu>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With some combinations of arch/compiler (e.g. arm-linux-gcc) the sizeof
operator on structure returns value greater than expected. In cases when the
structure is used for mapping PDU fields it may lead to unexpected results
(such as holes and alignment problems in skb data). __packed prevents this
undesired behavior.
Signed-off-by: NVitalii Demianets <vitas@nppfactor.kiev.ua>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It's a hot function, and we're better off not mixing types in the mask
calculations.  The compiler just ends up mixing 16-bit and 32-bit
operations, for no good reason.

So do everything in 'unsigned int' rather than mixing 'unsigned int'
masking with a 'umode_t' (16-bit) mode variable.

This, together with the parent commit (47a150ed: "Cache user_ns in
struct cred") makes acl_permission_check() much nicer.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If !CONFIG_USERNS, have current_user_ns() defined to (&init_user_ns).

Get rid of _current_user_ns.  This requires nsown_capable() to be
defined in capability.c rather than as static inline in capability.h,
so do that.

Request_key needs init_user_ns defined at current_user_ns if
!CONFIG_USERNS, so forward-declare that in cred.h if !CONFIG_USERNS
at current_user_ns() define.

Compile-tested with and without CONFIG_USERNS.
Signed-off-by: NSerge E. Hallyn <serge.hallyn@canonical.com>
[ This makes a huge performance difference for acl_permission_check(),
  up to 30%.  And that is one of the hottest kernel functions for loads
  that are pathname-lookup heavy.  ]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  SELinux: delete debugging printks from filename_trans rule processing

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
  net/9p/protocol.c: Fix a memory leak

* 'for-2639-rc7/i2c-fixes' of git://git.fluff.org/bjdooks/linux:
  i2c: pnx: Fix crash due to wrong init of timer->data

alg_data is already a pointer which must be passed directly.
Reported-by: NDieter Ripp <ripp@systecnet.com>
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ben Dooks <ben-i2c@fluff.org>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Since commit e9df2e8f (Use appropriate sock tclass setting for
routing lookup) we lost ability to properly add ECN codemarks to ipv6
TCP frames.

It seems like TCP_ECN_send() calls INET_ECN_xmit(), which only sets the
ECN bit in the IPv4 ToS field (inet_sk(sk)->tos), but after the patch,
what's checked is inet6_sk(sk)->tclass, which is a completely different
field.

Close bug https://bugzilla.kernel.org/show_bug.cgi?id=34322

[Eric Dumazet] : added the INET_ECN_dontxmit() fix and replace macros
by inline functions for clarity.
Signed-off-by: NSteinar H. Gunderson <sgunderson@bigfoot.com>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

kptr_restrict has been triggering bugs in apps such as perf, and it also makes
the system less useful by default, so turn it off by default.

This is how we generally handle security features that remove functionality,
such as firewall code or SELinux - they have to be configured and activated
from user-space.

Distributions can turn kptr_restrict on again via this line in
/etc/sysctrl.conf:

kernel.kptr_restrict = 1

( Also mark the variable __read_mostly while at it, as it's typically modified
  only once per bootup, or not at all. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When p9pdu_readf() is called with "s" attribute, it allocates a pointer that
will store a string. In p9dirent_read(), this pointer is not being released,
leading to out of memory errors.
This patch releases this pointer after string is copyed to dirent->d_name.
Signed-off-by: NPedro Scarapicchia Junior <pedro.scarapiccha@br.flextronics.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Changeset dcd39c90 ("ne-h8300: convert to
net_device_ops") broke ne-h8300 by adding 8390.o to the link. That
meant that lib8390.c was included twice, once in ne-h8300.c and once in
8390.c, subject to different macros. This patch reverts that by
avoiding the wrappers in 8390.c.

Fix based on commits 217cbfa8 ("mac8390:
fix regression caused during net_device_ops conversion") and
4e0168fa ("mac8390: fix build with
NET_POLL_CONTROLLER").
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@kernel.org
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Changeset 5618f0d1 ("hydra: convert to
net_device_ops") broke hydra by adding 8390.o to the link. That
meant that lib8390.c was included twice, once in hydra.c and once in
8390.c, subject to different macros. This patch reverts that by
avoiding the wrappers in 8390.c.

Fix based on commits 217cbfa8 ("mac8390:
fix regression caused during net_device_ops conversion") and
4e0168fa ("mac8390: fix build with
NET_POLL_CONTROLLER").
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@kernel.org
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Changeset b6114794 ("zorro8390: convert to
net_device_ops") broke zorro8390 by adding 8390.o to the link. That
meant that lib8390.c was included twice, once in zorro8390.c and once in
8390.c, subject to different macros. This patch reverts that by
avoiding the wrappers in 8390.c.

Fix based on commits 217cbfa8 ("mac8390:
fix regression caused during net_device_ops conversion") and
4e0168fa ("mac8390: fix build with
NET_POLL_CONTROLLER").
Reported-by: NChristian T. Steigies <cts@debian.org>
Suggested-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Tested-by: NChristian T. Steigies <cts@debian.org>
Cc: stable@kernel.org
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The filename_trans rule processing has some printk(KERN_ERR ) messages
which were intended as debug aids in creating the code but weren't removed
before it was submitted.  Remove them.
Reported-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NEric Paris <eparis@redhat.com>

* 'fix/asoc' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
  ASoC: WM8903: Fix Digital Capture Volume range
  ASoC: UDA134x: Remove POWER_OFF_ON_STANDBY define.
  ASoC: SSM2602: Fix reg_cache_size
  ASoC: SSM2602: Fix 'Mic Boost2' control
  ASoC: SSM2602: Properly annotate i2c probe and remove functions
  ASoC: sst_platform: add hw_free callback to fix resource leak
  ASoC: Don't crash on PM operations
  ASoC: JZ4740: Fix i2s shutdown

* 'stable/bug-fixes-for-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  x86/mm: Fix section mismatch derived from native_pagetable_reserve()
  x86,xen: introduce x86_init.mapping.pagetable_reserve
  Revert "xen/mmu: Add workaround "x86-64, mm: Put early page table high""

This reverts commit 49183b28.

Quoth Franz Melchior:

  "This patch introduces a bug on my infamous "Acer Travelmate
   5735Z-452G32Mnss": when KMS takes over, the frame buffer contents get
   completely garbled up on screen, with colored stripes and unreadable
   text (photo on request).  Only when X11 is started, the screen gets
   restored again.  Closing and re-opening the lid partly cures the
   mess, too: it makes the font readable, though horizontally stretched."
Acked-by: NKeith Packard <keithp@keithp.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* fbmem:
  fbmem: make read/write/ioctl use the frame buffer at open time
  fbcon: add lifetime refcount to opened frame buffers

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: ads7846 - remove unused variable from struct ads7845_ser_req
  Input: ads7846 - make transfer buffers DMA safe

With CONFIG_DEBUG_SECTION_MISMATCH=y I see these warnings in next-20110415:

  LD      vmlinux.o
  MODPOST vmlinux.o
WARNING: vmlinux.o(.text+0x1ba48): Section mismatch in reference from the function native_pagetable_reserve() to the function .init.text:memblock_x86_reserve_range()
The function native_pagetable_reserve() references
the function __init memblock_x86_reserve_range().
This is often because native_pagetable_reserve lacks a __init
annotation or the annotation of memblock_x86_reserve_range is wrong.

This patch fixes the issue.
Thanks to pipacs from PaX project for help on IRC.
Acked-by: N"H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NSedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Introduce a new x86_init hook called pagetable_reserve that at the end
of init_memory_mapping is used to reserve a range of memory addresses for
the kernel pagetable pages we used and free the other ones.

On native it just calls memblock_x86_reserve_range while on xen it also
takes care of setting the spare memory previously allocated
for kernel pagetable pages from RO to RW, so that it can be used for
other purposes.

A detailed explanation of the reason why this hook is needed follows.

As a consequence of the commit:

commit 4b239f45
Author: Yinghai Lu <yinghai@kernel.org>
Date:   Fri Dec 17 16:58:28 2010 -0800

    x86-64, mm: Put early page table high

at some point init_memory_mapping is going to reach the pagetable pages
area and map those pages too (mapping them as normal memory that falls
in the range of addresses passed to init_memory_mapping as argument).
Some of those pages are already pagetable pages (they are in the range
pgt_buf_start-pgt_buf_end) therefore they are going to be mapped RO and
everything is fine.
Some of these pages are not pagetable pages yet (they fall in the range
pgt_buf_end-pgt_buf_top; for example the page at pgt_buf_end) so they
are going to be mapped RW.  When these pages become pagetable pages and
are hooked into the pagetable, xen will find that the guest has already
a RW mapping of them somewhere and fail the operation.
The reason Xen requires pagetables to be RO is that the hypervisor needs
to verify that the pagetables are valid before using them. The validation
operations are called "pinning" (more details in arch/x86/xen/mmu.c).

In order to fix the issue we mark all the pages in the entire range
pgt_buf_start-pgt_buf_top as RO, however when the pagetable allocation
is completed only the range pgt_buf_start-pgt_buf_end is reserved by
init_memory_mapping. Hence the kernel is going to crash as soon as one
of the pages in the range pgt_buf_end-pgt_buf_top is reused (b/c those
ranges are RO).

For this reason we need a hook to reserve the kernel pagetable pages we
used and free the other ones so that they can be reused for other
purposes.
On native it just means calling memblock_x86_reserve_range, on Xen it
also means marking RW the pagetable pages that we allocated before but
that haven't been used before.

Another way to fix this is without using the hook is by adding a 'if
(xen_pv_domain)' in the 'init_memory_mapping' code and calling the Xen
counterpart, but that is just nasty.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

This reverts commit a3864783.

It does not work with certain AMD machines.

last_pfn = 0x100000 max_arch_pfn = 0x400000000
initial memory mapped : 0 - 02c3a000
Base memory trampoline at [ffff88000009b000] 9b000 size 20480
init_memory_mapping: 0000000000000000-0000000100000000
 0000000000 - 0100000000 page 4k
kernel direct mapping tables up to 100000000 @ ff7fb000-100000000
init_memory_mapping: 0000000100000000-00000001e0800000
 0100000000 - 01e0800000 page 4k
kernel direct mapping tables up to 1e0800000 @ 1df0f3000-1e0000000
xen: setting RW the range fffdc000 - 100000000
RAMDISK: 0203b000 - 02c3a000
No NUMA configuration found
Faking a node at 0000000000000000-00000001e0800000
NUMA: Using 63 for the hash shift.
Initmem setup node 0 0000000000000000-00000001e0800000
  NODE_DATA [00000001dfffb000 - 00000001dfffffff]
BUG: unable to handle kernel NULL pointer dereference at           (null)
IP: [<ffffffff81cf6a75>] setup_node_bootmem+0x18a/0x1ea
PGD 0
Oops: 0003 [#1] SMP
last sysfs file:
CPU 0
Modules linked in:

Pid: 0, comm: swapper Not tainted 2.6.39-0-virtual #6~smb1
RIP: e030:[<ffffffff81cf6a75>]  [<ffffffff81cf6a75>] setup_node_bootmem+0x18a/0x1ea
RSP: e02b:ffffffff81c01e38  EFLAGS: 00010046
RAX: 0000000000000000 RBX: 00000001e0800000 RCX: 0000000000001040
RDX: 0000000000004100 RSI: 0000000000000000 RDI: ffff8801dfffb000
RBP: ffffffff81c01e58 R08: 0000000000000020 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000bfe400
FS:  0000000000000000(0000) GS:ffffffff81cca000(0000) knlGS:0000000000000000
CS:  e033 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000001c03000 CR4: 0000000000000660
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process swapper (pid: 0, threadinfo ffffffff81c00000, task ffffffff81c0b020)
Stack:
 0000000000000040 0000000000000001 0000000000000000 ffffffffffffffff
 ffffffff81c01e88 ffffffff81cf6c25 0000000000000000 0000000000000000
 ffffffff81cf687f 0000000000000000 ffffffff81c01ea8 ffffffff81cf6e45
Call Trace:
 [<ffffffff81cf6c25>] numa_register_memblks.constprop.3+0x150/0x181
 [<ffffffff81cf687f>] ? numa_add_memblk+0x7c/0x7c
 [<ffffffff81cf6e45>] numa_init.part.2+0x1c/0x7c
 [<ffffffff81cf687f>] ? numa_add_memblk+0x7c/0x7c
 [<ffffffff81cf6f67>] numa_init+0x6c/0x70
 [<ffffffff81cf7057>] initmem_init+0x39/0x3b
 [<ffffffff81ce5865>] setup_arch+0x64e/0x769
 [<ffffffff815e43c1>] ? printk+0x51/0x53
 [<ffffffff81cdf92b>] start_kernel+0xd4/0x3f3
 [<ffffffff81cdf388>] x86_64_start_reservations+0x132/0x136
 [<ffffffff81ce2ed4>] xen_start_kernel+0x588/0x58f
Code: 41 00 00 48 8b 3c c5 a0 24 cc 81 31 c0 40 f6 c7 01 74 05 aa 66 ba ff 40 40 f6 c7 02 74 05 66 ab 83 ea 02 89 d1 c1 e9 02 f6 c2 02 <f3> ab 74 02 66 ab 80 e2 01 74 01 aa 49 63 c4 48 c1 eb 0c 44 89
RIP  [<ffffffff81cf6a75>] setup_node_bootmem+0x18a/0x1ea
 RSP <ffffffff81c01e38>
CR2: 0000000000000000
---[ end trace a7919e7f17c0a725 ]---
Kernel panic - not syncing: Attempted to kill the idle task!
Pid: 0, comm: swapper Tainted: G      D     2.6.39-0-virtual #6~smb1
Reported-by: NStefan Bader <stefan.bader@canonical.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: fix oops in revalidate when called with NULL nameidata

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc32: Fixed unaligned memory copying in function __csum_partial_copy_sparc_generic
  sparc32: fix sparcstation 5 boot
  sparc32: fix section mismatch warnings in apc, pmc and time_32

* 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm:
  ARM: 6870/1: The mandatory barrier rmb() must be a dsb() in for device accesses
  ARM: 6892/1: handle ptrace requests to change PC during interrupted system calls
  ARM: 6890/1: memmap: only free allocated memmap entries when using SPARSEMEM
  ARM: zImage: the page table memory must be considered before relocation
  ARM: zImage: make sure not to relocate on top of the relocation code
  ARM: zImage: Fix bad SP address after relocating kernel
  ARM: zImage: make sure the stack is 64-bit aligned
  ARM: RiscPC: acornfb: fix section mismatches
  ARM: RiscPC: etherh: fix section mismatches

read/write/ioctl on a fbcon file descriptor has traditionally used the
fbcon not when it was opened, but as it was at the time of the call.
That makes no sense, but the lack of sense is much more obvious now that
we properly ref-count the usage - it means that the ref-counting doesn't
actually protect operations we do on the frame buffer.

This changes it to look at the fb_info that we got at open time, but in
order to avoid using a frame buffer long after it has been unregistered,
we do verify that it is still current, and return -ENODEV if not.
Acked-by: NTim Gardner <tim.gardner@canonical.com>
Tested-by: NDaniel J Blueman <daniel.blueman@gmail.com>
Tested-by: NAnca Emanuel <anca.emanuel@gmail.com>
Cc: Bruno Prémont <bonbons@linux-vserver.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Andy Whitcroft <andy.whitcroft@canonical.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>