After a newly plugged CPU sets the cpu_online bit it enables
interrupts and goes idle. The cpu which brought up the new cpu waits
for the cpu_online bit and when it observes it, it sets the cpu_active
bit for this cpu. The cpu_active bit is the relevant one for the
scheduler to consider the cpu as a viable target.

With forced threaded interrupt handlers which imply forced threaded
softirqs we observed the following race:

cpu 0                         cpu 1

bringup(cpu1);
                              set_cpu_online(smp_processor_id(), true);
		              local_irq_enable();
while (!cpu_online(cpu1));
                              timer_interrupt()
                                -> wake_up(softirq_thread_cpu1);
                                     -> enqueue_on(softirq_thread_cpu1, cpu0);

                                                                        ^^^^

cpu_notify(CPU_ONLINE, cpu1);
  -> sched_cpu_active(cpu1)
     -> set_cpu_active((cpu1, true);

When an interrupt happens before the cpu_active bit is set by the cpu
which brought up the newly onlined cpu, then the scheduler refuses to
enqueue the woken thread which is bound to that newly onlined cpu on
that newly onlined cpu due to the not yet set cpu_active bit and
selects a fallback runqueue. Not really an expected and desirable
behaviour.

So far this has only been observed with forced hard/softirq threading,
but in theory this could happen without forced threaded hard/softirqs
as well. It's probably unobservable as it would take a massive
interrupt storm on the newly onlined cpu which causes the softirq loop
to wake up the softirq thread and an even longer delay of the cpu
which waits for the cpu_online bit.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Peter Zijlstra <peterz@infradead.org>
Cc: stable@kernel.org # 2.6.39

Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  genirq: Ensure we locate the passed IRQ in irq_alloc_descs()
  genirq: Fix descriptor init on non-sparse IRQs
  irq: Handle spurios irq detection for threaded irqs
  genirq: Print threaded handler in spurious debug output

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86/amd-iommu: Fix boot crash with hidden PCI devices
  x86/amd-iommu: Use only per-device dma_ops
  x86/amd-iommu: Fix 3 possible endless loops

Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Fix/clarify set_task_cpu() locking rules
  lockdep: Fix lock_is_held() on recursion
  sched: Fix schedstat.nr_wakeups_migrate
  sched: Fix cross-cpu clock sync on remote wakeups

* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm/nv40: fall back to paged dma object for the moment
  drm/nouveau: fix leak of gart mm node
  drm/nouveau: fix vram page mapping when crossing page table boundaries
  drm/nv17-nv40: Fix modesetting failure when pitch == 4096px (fdo bug 35901).
  drm/nouveau: don't create accel engine objects when noaccel=1
  drm/nvc0: recognise 0xdX chipsets as NV_C0
  drm/i915: Add a no lvds quirk for the Asus EeeBox PC EB1007
  drm/i915: Share the common force-audio property between connectors
  drm/i915: Remove unused enum "chip_family"
  drm/915: fix relaxed tiling on gen2: tile height
  drm/i915/crt: Explicitly return false if connected to a digital monitor
  drm/i915: Replace ironlake_compute_wm0 with g4x_compute_wm0
  drm/i915: Only print out the actual number of fences for i915_error_state
  drm/i915: s/addr & ~PAGE_MASK/offset_in_page(addr)/
  drm: i915: correct return status in intel_hdmi_mode_valid()
  drm/i915: fix regression after clock gating init split
  drm/i915: fix if statement in ivybridge irq handler

* 'drm-radeon-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm/radeon/kms/atom: fix PHY init
  drm/radeon/kms: add missing Evergreen texture formats to the CS parser
  drm/radeon/kms: viewport height has to be even
  drm/radeon/kms: remove duplicate reg from r600 safe regs
  drm/radeon/kms: add support for Llano Fusion APUs
  drm/radeon/kms: add llano pci ids
  drm/radeon/kms: fill in asic struct for llano
  drm/radeon/kms: add family ids for llano APUs
  drm/radeon: fix oops in ttm reserve when pageflipping (v2)
  drm/radeon/kms: clean up the radeon kms Kconfig
  drm/radeon/kms: fix thermal sensor reading on juniper
  drm/radeon/kms: add missing case for cayman thermal sensor
  drm/radeon/kms: add blit support for cayman (v2)
  drm/radeon/kms/blit: workaround some hw issues on evergreen+

Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  timers: Consider slack value in mod_timer()
  clockevents: Handle empty cpumask gracefully

* 'kvm-updates/3.0' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: Initialize kvm before registering the mmu notifier
  KVM: x86: use proper port value when checking io instruction permission
  KVM: add missing void __user * cast to access_ok() call

We had to say goodbye when David passed away recently.  David had a
huge impact on our community, both personally in the lives of the
people he worked with, and technically in the design and maintenance
of several subsystems.  He is greatly missed.

He also leaves behind a number of much loved subsystems now orphaned.
This patch updates the MAINTAINERS file for the areas that David was
responsible for and adds an entry for him to the CREDITS file.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Harry Wei <harryxiyou@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6:
  fat: Fix corrupt inode flags when remove ATTR_SYS flag

_sdata needs to be declared in the linker script now as of commit
a2d063ac ("extable, core_kernel_data(): Make sure all archs define
_sdata")
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

die_if_no_fixup() shouldn't use get_user() as it doesn't call set_fs() to
indicate that it wants to probe a kernel address.  Instead it should use
probe_kernel_read().

This fixes the problem of gdb seeing SIGILL rather than SIGTRAP when hitting
the KGDB special breakpoint upon SysRq+g being seen.  The problem was that
die_if_no_fixup() was failing to read the opcode of the instruction that caused
the exception, and thus not fixing up the exception.

This caused gdb to get a S04 response to the $? request in its remote protocol
rather than S05 - which would then cause it to continue with $C04 rather than
$c in an attempt to pass the signal onto the inferior process.  The kernel,
however, does not support $Cnn, and so objects by returning an E22 response,
indicating an error.  gdb does not expect this and prints:

	warning: Remote failure reply: E22

and then returns to the gdb command prompt unable to continue.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

One of the kernel debugger cacheflush variants escaped proper testing.  Two of
the labels are wrong, being derived from the code that was copied to construct
the variant.

The first label results in the following assembler message:

    AS      arch/mn10300/mm/cache-dbg-flush-by-reg.o
  arch/mn10300/mm/cache-dbg-flush-by-reg.S: Assembler messages:
  arch/mn10300/mm/cache-dbg-flush-by-reg.S:123: Error: symbol `debugger_local_cache_flushinv_no_dcache' is already defined

And the second label results in the following linker message:

  arch/mn10300/mm/built-in.o:(.text+0x1d39): undefined reference to `mn10300_local_icache_inv_range_reg_end'
  arch/mn10300/mm/built-in.o:(.text+0x1d39): relocation truncated to fit: R_MN10300_PCREL16 against undefined symbol `mn10300_local_icache_inv_range_reg_end'

To test this file the following configuration pieces must be set:

	CONFIG_AM34=y
	CONFIG_MN10300_CACHE_WBACK=y
	CONFIG_MN10300_DEBUGGER_CACHE_FLUSH_BY_REG=y
	CONFIG_MN10300_CACHE_MANAGE_BY_REG=y
	CONFIG_AM34_HAS_CACHE_SNOOP=n
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
  [S390] fix kvm defines for 31 bit compile
  [S390] use generic RCU page-table freeing code
  [S390] qdio: Split SBAL entry flags
  [S390] kvm-s390: fix stfle facilities numbers >=64
  [S390] kvm-s390: Fix host crash on misbehaving guests

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6: (21 commits)
  ARM: OMAP4: MMC: increase delay for pbias
  arm: omap2plus: move NAND_BLOCK_SIZE out of boards
  omap4: hwmod: Enable the keypad
  omap3: Free Beagle rev gpios when they are read, so others can read them later
  arm: omap3: beagle: Ensure msecure is mux'd to be able to set the RTC
  omap: rx51: Don't power up speaker amplifier at bootup
  omap: rx51: Set regulator V28_A always on
  ARM: OMAP4: MMC: no regulator off during probe for eMMC
  arm: omap2plus: fix ads7846 pendown gpio request
  ARM: OMAP2: Add missing iounmap in omap4430_phy_init
  ARM: omap4: Pass core and wakeup mux tables to omap4_mux_init
  ARM: omap2+: mux: Allow board mux settings to be NULL
  OMAP4: fix return value of omap4_l3_init
  OMAP: iovmm: fix SW flags passed by user
  arch/arm/mach-omap1/dma.c: Invert calls to platform_device_put and platform_device_del
  OMAP2+: mux: fix compilation warnings
  OMAP: SRAM: Fix warning: format '%08lx' expects type 'long unsigned int'
  arm: omap3: cm-t3517: fix section mismatch warning
  OMAP2+: Fix 9 section mismatch(es) warnings from mach-omap2/built-in.o
  ARM: OMAP2: Add missing include of linux/gpio.h
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes:
  GFS2: Processes waiting on inode glock that no processes are holding

Merge branch 'fbdev-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/fbdev-3.x

* 'fbdev-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/fbdev-3.x:
  video: Fix use-after-free by vga16fb on rmmod
  video: Convert vmalloc/memset to vzalloc
  efifb: Disallow manual bind and unbind
  efifb: Fix mismatched request/release_mem_region
  efifb: Enable write-combining
  drivers/video/pxa168fb.c: add missing clk_put
  drivers/video/imxfb.c: add missing clk_put
  fbdev: bf537-lq035: add missing blacklight properties type
  savagefb: Use panel CVT mode as default
  fbdev: sh_mobile_lcdcfb: Fix up fallout from MERAM changes.

* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  vfs: make unlink() and rmdir() return ENOENT in preference to EROFS
  lmLogOpen() broken failure exit
  usb: remove bad dput after dentry_unhash
  more conservative S_NOSEC handling

If user space attempts to remove a non-existent file or directory, and
the file system is mounted read-only, return ENOENT instead of EROFS.
Either error code is arguably valid/correct, but ENOENT is a more
specific error message.
Reported-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Callers of lmLogOpen() expect it to return -E... on failure exits, which
is what it returns, except for the case of blkdev_get_by_dev() failure.
It that case lmLogOpen() return the error with the wrong sign...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com>

Sergey reported a CONFIG_PROVE_RCU warning in push_rt_task where
set_task_cpu() was called with both relevant rq->locks held, which
should be sufficient for running tasks since holding its rq->lock
will serialize against sched_move_task().

Update the comments and fix the task_group() lockdep test.
Reported-and-tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1307115427.2353.3456.camel@twinsSigned-off-by: Ingo Molnar <mingo@elte.hu>

The main lock_is_held() user is lockdep_assert_held(), avoid false
assertions in lockdep_off() sections by unconditionally reporting the
lock is taken.

[ the reason this is important is a lockdep_assert_held() in ttwu()
  which triggers a warning under lockdep_off() as in printk() which
  can trigger another wakeup and lock up due to spinlock
  recursion, as reported and heroically debugged by Arne Jansen ]
Reported-and-tested-by: Arne Jansen <lists@die-jansens.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/1307398759.2497.966.camel@laptopSigned-off-by: Ingo Molnar <mingo@elte.hu>

Some PCIe cards ship with a PCI-PCIe bridge which is not
visible as a PCI device in Linux. But the device-id of the
bridge is present in the IOMMU tables which causes a boot
crash in the IOMMU driver.
This patch fixes by removing these cards from the IOMMU
handling. This is a pure -stable fix, a real fix to handle
this situation appriatly will follow for the next merge
window.

Cc: stable@kernel.org	# > 2.6.32
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

* 'nouveau/drm-nouveau-fixes' of /ssd/git/drm-nouveau-next:
  drm/nv40: fall back to paged dma object for the moment
  drm/nouveau: fix leak of gart mm node
  drm/nouveau: fix vram page mapping when crossing page table boundaries
  drm/nv17-nv40: Fix modesetting failure when pitch == 4096px (fdo bug 35901).
  drm/nouveau: don't create accel engine objects when noaccel=1
  drm/nvc0: recognise 0xdX chipsets as NV_C0

* 'keithp/drm-intel-fixes' of /ssd/git/drm-next:
  drm/i915: Add a no lvds quirk for the Asus EeeBox PC EB1007
  drm/i915: Share the common force-audio property between connectors
  drm/i915: Remove unused enum "chip_family"
  drm/915: fix relaxed tiling on gen2: tile height
  drm/i915/crt: Explicitly return false if connected to a digital monitor
  drm/i915: Replace ironlake_compute_wm0 with g4x_compute_wm0
  drm/i915: Only print out the actual number of fences for i915_error_state
  drm/i915: s/addr & ~PAGE_MASK/offset_in_page(addr)/
  drm: i915: correct return status in intel_hdmi_mode_valid()
  drm/i915: fix regression after clock gating init split
  drm/i915: fix if statement in ivybridge irq handler

PCI(E)GART isn't quite stable it seems, fall back to old method until I get
the time to sort it out properly.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

Hopefully the cause of nvc0 "page jumping" issue.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

Reported-by: Mario Bachmann <grafgrimm77@gmx.de>
Tested-by: Greg Turner <gmturner007@ameritech.net>
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

Fixes various potential oopses.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

Should hopefully get modesetting at least from this, it appears these are
GF119 chipsets.  Accel will come eventually, once I order a board.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

Unfortunatly there are systems where the AMD IOMMU does not
cover all devices. This breaks with the current driver as it
initializes the global dma_ops variable. This patch limits
the AMD IOMMU to the devices listed in the IVRS table fixing
DMA for devices not covered by the IOMMU.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

The driver contains several loops counting on an u16 value
where the exit-condition is checked against variables that
can have values up to 0xffff. In this case the loops will
never exit. This patch fixed 3 such loops.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

KVM is not available for 31 bit but the KVM defines cause warnings:

arch/s390/include/asm/pgtable.h: In function 'ptep_test_and_clear_user_dirty':
arch/s390/include/asm/pgtable.h:817: warning: integer constant is too large for 'unsigned long' type
arch/s390/include/asm/pgtable.h:818: warning: integer constant is too large for 'unsigned long' type
arch/s390/include/asm/pgtable.h: In function 'ptep_test_and_clear_user_young':
arch/s390/include/asm/pgtable.h:837: warning: integer constant is too large for 'unsigned long' type
arch/s390/include/asm/pgtable.h:838: warning: integer constant is too large for 'unsigned long' type

Add 31 bit versions of the KVM defines to remove the warnings.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Replace the s390 specific rcu page-table freeing code with the
generic variant. This requires to duplicate the definition for the
struct mmu_table_batch as s390 does not use the generic tlb flush
code.

While we are at it remove the restriction that page table fragments
can not be reused after a single fragment has been freed with rcu
and split out allocation and freeing of page tables with pgstes.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

The qdio SBAL entry flag is made-up of four different values that are
independent of one another. Some of the bits are reserved by the
hardware and should not be changed by qdio. Currently all four values
are overwritten since the SBAL entry flag is defined as an u32.

Split the SBAL entry flag into four u8's as defined by the hardware
and don't touch the reserved bits.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Currently KVM masks out the known good facilities only for the first
double word, but passed the 2nd double word without filtering. This
breaks some code on newer systems:

[    0.593966] ------------[ cut here ]------------
[    0.594086] WARNING: at arch/s390/oprofile/hwsampler.c:696
[    0.594213] Modules linked in:
[    0.594321] Modules linked in:
[    0.594439] CPU: 0 Not tainted 3.0.0-rc1 #46
[    0.594564] Process swapper (pid: 1, task: 00000001effa8038, ksp: 00000001effafab8)
[    0.594735] Krnl PSW : 0704100180000000 00000000004ab89a (hwsampler_setup+0x75a/0x7b8)
[    0.594910]            R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:1 PM:0 EA:3
[    0.595120] Krnl GPRS: ffffffff00000000 00000000ffffffea ffffffffffffffea 00000000004a98f8
[    0.595351]            00000000004aa002 0000000000000001 000000000080e720 000000000088b9f8
[    0.595522]            000000000080d3e8 0000000000000000 0000000000000000 000000000080e464
[    0.595725]            0000000000000000 00000000005db198 00000000004ab3a2 00000001effafd98
[    0.595901] Krnl Code: 00000000004ab88c: c0e5000673ca        brasl   %r14,57a020
[    0.596071]            00000000004ab892: a7f4fc77            brc     15,4ab180
[    0.596276]            00000000004ab896: a7f40001            brc     15,4ab898
[    0.596454]           >00000000004ab89a: a7c8ffa1            lhi     %r12,-95
[    0.596657]            00000000004ab89e: a7f4fc71            brc     15,4ab180
[    0.596854]            00000000004ab8a2: a7f40001            brc     15,4ab8a4
[    0.597029]            00000000004ab8a6: a7f4ff22            brc     15,4ab6ea
[    0.597230]            00000000004ab8aa: c0200011009a        larl    %r2,6cb9de
[    0.597441] Call Trace:
[    0.597511] ([<00000000004ab3a2>] hwsampler_setup+0x262/0x7b8)
[    0.597676]  [<0000000000875812>] oprofile_arch_init+0x32/0xd0
[    0.597834]  [<0000000000875788>] oprofile_init+0x28/0x74
[    0.597991]  [<00000000001001be>] do_one_initcall+0x3a/0x170
[    0.598151]  [<000000000084fa22>] kernel_init+0x142/0x1ec
[    0.598314]  [<000000000057db16>] kernel_thread_starter+0x6/0xc
[    0.598468]  [<000000000057db10>] kernel_thread_starter+0x0/0xc
[    0.598606] Last Breaking-Event-Address:
[    0.598707]  [<00000000004ab896>] hwsampler_setup+0x756/0x7b8
[    0.598863] ---[ end trace ce3179037f4e3e5b ]---

So lets also mask the 2nd double word. Facilites 66,76,76,77 should be fine.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

commit 9ff4cfb3 ([S390] kvm-390: Let
kernel exit SIE instruction on work) fixed a problem of commit
commit cd3b70f5 ([S390] virtualization
aware cpu measurement) but uncovered another one.

If a kvm guest accesses guest real memory that doesnt exist, the
page fault handler calls the sie hook, which then rewrites
the return psw from sie_inst to either sie_exit or sie_reenter.
On return, the page fault handler will then detect the wrong access
as a kernel fault causing a kernel oops in sie_reenter or sie_exit.

We have to add these two addresses to the exception  table to allow
graceful exits.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Since fb_info is now refcounted and thus may get freed at any time it
gets unregistered module unloading will try to unregister framebuffer
as stored in platform data on probe though this pointer may
be stale.

Cleanup platform data on framebuffer release.

CC: stable@kernel.org
Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>