found a system where x2apic reports an MSI-X irq initialization
failure:

[  302.859446] igbvf 0000:81:10.4: enabling device (0000 -> 0002)
[  302.874369] igbvf 0000:81:10.4: using 64bit DMA mask
[  302.879023] igbvf 0000:81:10.4: using 64bit consistent DMA mask
[  302.894386] igbvf 0000:81:10.4: enabling bus mastering
[  302.898171] igbvf 0000:81:10.4: setting latency timer to 64
[  302.914050] reserve_memtype added 0xefb08000-0xefb0c000, track uncached-minus, req uncached-minus, ret uncached-minus
[  302.933839] reserve_memtype added 0xefb28000-0xefb29000, track uncached-minus, req uncached-minus, ret uncached-minus
[  302.940367]   alloc irq_desc for 265 on node 4
[  302.956874]   alloc kstat_irqs on node 4
[  302.959452] alloc irq_2_iommu on node 0
[  302.974328] igbvf 0000:81:10.4: irq 265 for MSI/MSI-X
[  302.977778]   alloc irq_desc for 266 on node 4
[  302.980347]   alloc kstat_irqs on node 4
[  302.995312] free_memtype request 0xefb28000-0xefb29000
[  302.998816] igbvf 0000:81:10.4: Failed to initialize MSI-X interrupts.

... it turns out that when trying to enable MSI-X,
__assign_irq_vector(new, cfg_new, apic->target_cpus()) can not
get vector because for x2apic target-cpus returns cpumask_of(0)

Update that to online_mask like xapic.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <4A785AFF.3050902@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

With CONFIG_STACK_PROTECTOR turned on, VMI doesn't boot with
more than one processor. The problem is with the gs value not
being initialized correctly when registering the secondary
processor for VMI's case.

The patch below initializes the gs value for the AP to
__KERNEL_STACK_CANARY. Without this the secondary processor
keeps on taking a GP on every gs access.
Signed-off-by: Alok N Kataria <akataria@vmware.com>
Cc: <stable@kernel.org> # for v2.6.30.x
LKML-Reference: <1249425262.18955.40.camel@ank32.eng.vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (32 commits)
  MIPS: Wire up accept4 syscall.
  MIPS: VPE: Delete unused function get_tc_unused().
  MIPS: VPE: Fix bogus indentation.
  MIPS: VPE: Make various functions static.
  MIPS: VPE: Free relocation chain on error.
  MIPS: VPE: Fix compiler warning.
  MIPS: Module: Make error messages unique.
  MIPS: Octeon: Run IPI code with interrupts disabled.
  MIPS: Jazz: Fix read buffer overflow
  MIPS: Use DIV_ROUND_CLOSEST
  MIPS: MTX-1: Request button GPIO before setting its direction
  MIPS: AR7: Override CFLAGS with -Werror
  MIPS: AR7: Remove unused tnetd7200_get_clock function
  MIPS: AR7: Use DMA_BIT_MASK(nn) instead of deprecated DMA_nnBIT_MASK
  MIPS: AR7: Fix build failures when CONFIG_SERIAL_8250 is not enabled
  MIPS: Fix read buffer overflow
  MIPS: AR7: Fix build warning on memory.c
  MIPS: Octeon PCIe: Make hardware and software bus numbers match.
  MIPS: RBTX4939: Fix IOC pin-enable register updating
  MIPS: Simplify and correct interrupt handling for MSP4200
  ...

* 'fix/hda' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
  ALSA: hda - Read buffer overflow
  ALSA: hda: Correct EAPD for Dell Inspiron 1525
  ALSA: hda: warn on spurious response
  ALSA: hda: remember last command for each codec
  ALSA: hda: read CORBWP inside reg_lock
  ALSA: hda: take reg_lock in azx_init_cmd_io/azx_free_cmd_io
  ALSA: hda: take cmd_mutex in probe_codec()
  ALSA: hda: track CIRB/CORB command/response states for each codec
  ALSA: hda - Fix quirk for Toshiba Satellite A135-S4527

* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6:
  tty-ldisc: be more careful in 'put_ldisc' locking
  tty-ldisc: turn ldisc user count into a proper refcount
  tty-ldisc: make refcount be atomic_t 'users' count

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  Make SCSI SG v4 driver enabled by default and remove EXPERIMENTAL dependency, since udev depends on BSG
  block: Update topology documentation
  block: Stack optimal I/O size
  block: Add a wrapper for setting minimum request size without a queue
  block: Make blk_queue_stack_limits use the new stacking interface

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (47 commits)
  ehea: Fix napi list corruption on ifconfig down
  igbvf: Allow VF driver to correctly recognize failure to set mac
  3c59x: Fix build failure with gcc 3.2
  sky2: Avoid transmits during sky2_down()
  iwlagn: do not send key clear commands when rfkill enabled
  libertas: Read buffer overflow
  drivers/net/wireless: introduce missing kfree
  drivers/net/wireless/iwlwifi: introduce missing kfree
  zd1211rw: fix unaligned access in zd_mac_rx
  cfg80211: fix regression on beacon world roaming feature
  cfg80211: add two missing NULL pointer checks
  ixgbe: Patch to modify 82598 PCIe completion timeout values
  bluetooth: rfcomm_init bug fix
  mlx4_en: Fix double pci unmapping.
  mISDN: Fix handling of receive buffer size in L1oIP
  pcnet32: VLB support fixes
  pcnet32: remove superfluous NULL pointer check in pcnet32_probe1()
  net: restore the original spinlock to protect unicast list
  netxen: fix coherent dma mask setting
  mISDN: Read buffer overflow
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6: (23 commits)
  [SCSI] sd: Avoid sending extended inquiry to legacy devices
  [SCSI] libsas: fix wide port hotplug issues
  [SCSI] libfc: fix a circular locking warning during sending RRQ
  [SCSI] qla4xxx: Remove hiwat code so scsi eh does not get escalated when we can make progress
  [SCSI] qla4xxx: Fix srb lookup in qla4xxx_eh_device_reset
  [SCSI] qla4xxx: Fix Driver Fault Recovery Completion
  [SCSI] qla4xxx: add timeout handler
  [SCSI] qla4xxx: Correct Extended Sense Data Errors
  [SCSI] libiscsi: disable bh in and abort handler.
  [SCSI] zfcp: Fix tracing of request id for abort requests
  [SCSI] zfcp: Fix wka port processing
  [SCSI] zfcp: avoid double notify in lowmem scenario
  [SCSI] zfcp: Add port only once to FC transport class
  [SCSI] zfcp: Recover from stalled outbound queue
  [SCSI] zfcp: Fix erp escalation procedure
  [SCSI] zfcp: Fix logic for physical port close
  [SCSI] zfcp: Use -EIO for SBAL allocation failures
  [SCSI] zfcp: Use unchained mode for small ct and els requests
  [SCSI] zfcp: Use correct flags for zfcp_erp_notify
  [SCSI] zfcp: Return -ENOMEM for allocation failures in zfcp_fsf
  ...

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp:
  amd64_edac: print debug statements only on error
  amd64_edac: fix ECC checking

* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm/ttm: Read buffer overflow
  drm/radeon: Read buffer overflow
  drm/ttm: Fix a sync object leak.
  drm/radeon/kms: fix memory leak in radeon_driver_load_kms
  drm/radeon/kms: fix nomodeset.
  drm/ttm: Fix a potential comparison of structs.
  drm/radeon/kms: fix rv515 VRAM initialisation.
  drm/radeon: add some new r7xx pci ids
  drm: Catch stop possible NULL pointer reference
  drm: Small logic fix in drm_mode_setcrtc

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-2.6:
  parisc: hppb.c - fix printk format strings
  parisc: parisc-agp.c - use correct page_mask function
  parisc: sticore.c - check return values
  parisc: dino.c - check return value of pci_assign_resource()
  parisc: hp_sdc_mlc.c - check return value of down_trylock()
  parisc: includecheck fix for ccio-dma.c
  parisc: Set correct bit in protection flags
  parisc: isa-eeprom - Fix loff_t usage
  parisc: fixed faulty check in lba_pci
  parisc: Fix read buffer overflow in pdc_stable driver
  parisc: Fix GOT overflow during module load on 64bit kernel

flex_array_get() calculates an index value, then drops it on the floor;
simply remove it.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Acked-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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

* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf_counter: Set the CONFIG_PERF_COUNTERS default to y if CONFIG_PROFILING=y
  perf: Fix read buffer overflow
  perf top: Add mwait_idle_with_hints to skip_symbols[]
  perf tools: Fix faulty check
  perf report: Update for the new FORK/EXIT events
  perf_counter: Full task tracing
  perf_counter: Collapse inherit on read()
  tracing, perf_counter: Add help text to CONFIG_EVENT_PROFILE
  perf_counter tools: Fix link errors with older toolchains

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

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Fix race in cpupri introduced by cpumask_var changes
  sched: Fix latencytop and sleep profiling vs group scheduling

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:
  posix-timers: Fix oops in clock_nanosleep() with CLOCK_MONOTONIC_RAW

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

* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: Fix missing function_graph events when we splice_read from trace_pipe
  tracing: Fix invalid function_graph entry
  trace: stop tracer in oops_enter()
  ftrace: Only update $offset when we update $ref_func
  ftrace: Fix the conditional that updates $ref_func
  tracing: only truncate ftrace files when O_TRUNC is set
  tracing: show proper address for trace-printk format

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6:
  mfd: twl4030 irq fixes

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

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Work around compilation warning in arch/x86/kernel/apm_32.c
  x86, UV: Complete IRQ interrupt migration in arch_enable_uv_irq()
  x86, 32-bit: Fix double accounting in reserve_top_address()
  x86: Don't use current_cpu_data in x2apic phys_pkg_id
  x86, UV: Fix UV apic mode
  x86, UV: Fix macros for accessing large node numbers
  x86, UV: Delete mapping of MMR rangs mapped by BIOS
  x86, UV: Handle missing blade-local memory correctly
  x86: fix assembly constraints in native_save_fl()
  x86, msr: execute on the correct CPU subset
  x86: Fix assert syntax in vmlinux.lds.S
  x86: Make 64-bit efi_ioremap use ioremap on MMIO regions
  x86: Add quirk to make Apple MacBook5,2 use reboot=pci
  x86: Fix CPA memtype reserving in the set_pages_array*() cases
  x86, pat: Fix set_memory_wc related corruption
  x86: fix section mismatch for i386 init code

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] Make cpufreq suspend code conditional on powerpc.
  [CPUFREQ] Fix a kobject reference bug related to managed CPUs
  [CPUFREQ] Do not set policy for offline cpus
  [CPUFREQ] Fix NULL pointer dereference regression in conservative governor

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2:
  nilfs2: fix missing unlock in error path of nilfs_mdt_write_page
  nilfs2: fix oops due to inconsistent state in page with discrete b-tree nodes

* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  [CIFS] Update readme to reflect forceuid mount parms
  cifs: Read buffer overflow
  cifs: show noforceuid/noforcegid mount options (try #2)
  cifs: reinstate original behavior when uid=/gid= options are specified
  [CIFS] Updates fs/cifs/CHANGES
  cifs: fix error handling in mount-time DFS referral chasing code

Use 'atomic_dec_and_lock()' to make sure that we always hold the
tty_ldisc_lock when the ldisc count goes to zero. That way we can never
race against 'tty_ldisc_try()' increasing the count again.
Reported-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@mail.by>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

By using the user count for the actual lifetime rules, we can get rid of
the silly "wait_for_idle" logic, because any busy ldisc will
automatically stay around until the last user releases it.  This avoids
a host of odd issues, and simplifies the code.

So now, when the last ldisc reference is dropped, we just release the
ldisc operations struct reference, and free the ldisc.

It looks obvious enough, and it does work for me, but the counting
_could_ be off. It probably isn't (bad counting in the new version would
generally imply that the old code did something really bad, like free an
ldisc with a non-zero count), but it does need some testing, and
preferably somebody looking at it.

With this change, both 'tty_ldisc_put()' and 'tty_ldisc_deref()' are
just aliases for the new ref-counting 'put_ldisc()'. Both of them
decrement the ldisc user count and free it if it goes down to zero.
They're identical functions, in other words.

But the reason they still exist as sepate functions is that one of them
was exported (tty_ldisc_deref) and had a stupid name (so I don't want to
use it as the main name), and the other one was used in multiple places
(and I didn't want to make the patch larger just to rename the users).

In addition to the refcounting, I did do some minimal cleanup. For
example, now "tty_ldisc_try()" actually returns the ldisc it got under
the lock, rather than returning true/false and then the caller would
look up the ldisc again (now without the protection of the lock).

That said, there's tons of dubious use of 'tty->ldisc' without obviously
proper locking or refcounting left. I expressly did _not_ want to try to
fix it all, keeping the patch minimal. There may or may not be bugs in
that kind of code, but they wouldn't be _new_ bugs.

That said, even if the bugs aren't new, the timing and lifetime will
change. For example, some silly code may depend on the 'tty->ldisc'
pointer not changing because they hold a refcount on the 'ldisc'. And
that's no longer true - if you hold a ref on the ldisc, the 'ldisc'
itself is safe, but tty->ldisc may change.

So the proper locking (remains) to hold tty->ldisc_mutex if you expect
tty->ldisc to be stable. That's not really a _new_ rule, but it's an
example of something that the old code might have unintentionally
depended on and hidden bugs.

Whatever. The patch _looks_ sensible to me. The only users of
ldisc->users are:
 - get_ldisc() - atomically increment the count

 - put_ldisc() - atomically decrements the count and releases if zero

 - tty_ldisc_try_get() - creates the ldisc, and sets the count to 1.
   The ldisc should then either be released, or be attached to a tty.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tested-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@mail.by>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

This is pure preparation of changing the ldisc reference counting to be
a true refcount that defines the lifetime of the ldisc.  But this is a
purely syntactic change for now to make the next steps easier.

This patch should make no semantic changes at all. But I wanted to make
the ldisc refcount be an atomic (I will be touching it without locks
soon enough), and I wanted to rename it so that there isn't quite as
much confusion between 'ldo->refcount' (ldisk operations refcount) and
'ld->refcount' (ldisc refcount itself) in the same file.

So it's now an atomic 'ld->users' count. It still starts at zero,
despite having a reference from 'tty->ldisc', but that will change once
we turn it into a _real_ refcount.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tested-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@mail.by>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Make SCSI SG v4 driver enabled by default and remove EXPERIMENTAL dependency, since udev depends on BSG

Make Block Layer SG support v4 the default, since recent udev versions
depend on this to access serial numbers and other low level info properly.

This should be backported to older kernels as well, since most distros have
enabled this for a long time.
Signed-off-by: John Stoffel <john@stoffel.org>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

This patch fixes the napi list handling when an ehea interface is shut
down to avoid corruption of the napi list.
Signed-off-by: Hannes Hering <hering2@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The VF driver was not correctly recognizing that it did not correctly set
it's mac address.  As a result the VF driver was unable to receive network
traffic until being unloaded and reloaded.  The issue was root caused to
the fact that the CTS bit was not taken into account when checking for the
request being NAKed.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The suspend code runs with interrupts disabled, and the powerpc workaround we
do in the cpufreq suspend hook calls the drivers ->get method.

powernow-k8's ->get does an smp_call_function_single
which needs interrupts enabled

cpufreq's suspend/resume code was added in 42d4dc3f to work around
a hardware problem on ppc powerbooks.  If we make all this code
conditional on powerpc, we avoid the issue above.
Signed-off-by: Dave Jones <davej@redhat.com>

The first offline/online cycle is successful, the second not.
Doing:
echo 0 >cpu1/online
echo 1 >cpu1/online
echo 0 >cpu1/online

The last command will trigger:
Jul 22 14:39:50 linux kernel: [  593.210125] ------------[ cut here ]------------
Jul 22 14:39:50 linux kernel: [  593.210139] WARNING: at lib/kref.c:43 kref_get+0x23/0x2b()
Jul 22 14:39:50 linux kernel: [  593.210144] Hardware name: To Be Filled By O.E.M.
Jul 22 14:39:50 linux kernel: [  593.210148] Modules linked in: powernow_k8
Jul 22 14:39:50 linux kernel: [  593.210158] Pid: 378, comm: kondemand/2 Tainted: G        W  2.6.31-rc2 #38
Jul 22 14:39:50 linux kernel: [  593.210163] Call Trace:
Jul 22 14:39:50 linux kernel: [  593.210171]  [<ffffffff812008e8>] ? kref_get+0x23/0x2b
Jul 22 14:39:50 linux kernel: [  593.210181]  [<ffffffff81041926>] warn_slowpath_common+0x77/0xa4
Jul 22 14:39:50 linux kernel: [  593.210190]  [<ffffffff81041962>] warn_slowpath_null+0xf/0x11
Jul 22 14:39:50 linux kernel: [  593.210198]  [<ffffffff812008e8>] kref_get+0x23/0x2b
Jul 22 14:39:50 linux kernel: [  593.210206]  [<ffffffff811ffa19>] kobject_get+0x1a/0x22
Jul 22 14:39:50 linux kernel: [  593.210214]  [<ffffffff813e815d>] cpufreq_cpu_get+0x8a/0xcb
Jul 22 14:39:50 linux kernel: [  593.210222]  [<ffffffff813e87d1>] __cpufreq_driver_getavg+0x1d/0x67
Jul 22 14:39:50 linux kernel: [  593.210231]  [<ffffffff813ea18f>] do_dbs_timer+0x158/0x27f
Jul 22 14:39:50 linux kernel: [  593.210240]  [<ffffffff810529ea>] worker_thread+0x200/0x313
...

The output continues on every do_dbs_timer ondemand freq checking poll.
This regression was introduced by git commit:
3f4a782b

The policy is released when the cpufreq device is removed in:
__cpufreq_remove_dev():
	/* if this isn't the CPU which is the parent of the kobj, we
	 * only need to unlink, put and exit
	 */

Not creating the symlink is not sever at all.
As long as:
sysfs_remove_link(&sys_dev->kobj, "cpufreq");
handles it gracefully that the symlink did not exist.
Possibly no error should be returned at all, because ondemand
governor would still provide the same functionality.
Userspace in userspace gov case might be confused if the link
is missing.

Resolves http://bugzilla.kernel.org/show_bug.cgi?id=13903

CC: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
CC: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>

Suspend/Resume fails on multi socket, multi core systems because the cpufreq
code erroneously sets the per_cpu policy_cpu value when a logical cpu is
offline.

This most notably results in missing sysfs files that are used to set the
cpu frequencies of the various cpus.
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Dave Jones <davej@redhat.com>

Commit ee88415c
introduced this regression when it removed enable bit in cpu_dbs_info_s.
That added a possibility of dbs_cpufreq_notifier getting called for a
CPU that is not yet managed by conservative governor. That will happen
as the transition notifier is set as soon as one CPU switches to
conservative governor and other CPUs can get a NULL pointer dereference
without the enable bit check. Add the enable bit back again.
Reported-by: Lermytte Christophe <Christophe.Lermytte@thomson.net>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>

The TWL4030 IRQ handler has a bug which leads to spinlock lock-up. It is
calling the 'unmask' function in a process context. :The mask/unmask/ack
functions are only designed to be called from the IRQ handler code,
or the proper API interfaces found in linux/interrupt.h.

Also there is no need to have IRQ chaining mechanism. The right way to
handle this is to claim the parent interrupt as a standard interrupt
and arrange for handle_twl4030_pih to take care of the rest of the devices.

Mail thread on this issue can be found at:
http://marc.info/?l=linux-arm-kernel&m=124629940123396&w=2Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

If user has already enabled profiling support in the kernel
(for oprofile, old-style profiling of ftrace) then offer up
perfcounters with a y default in interactive kconfig sessions.

Still keep it off by default otherwise.

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

The following fix was initially inspired by David Howells fix
few days back:

  http://lkml.org/lkml/2009/7/9/109

However, Ingo disapproves such fixes as it's dangerous (it can
hide future, relevant warnings) - in something as
performance-uncritical.

So, initialize 'err' to '0' to work around a GCC false positive
warning:

  http://lkml.org/lkml/2009/7/18/89

Signed-off-by: Subrata Modak<subrata@linux.vnet.ibm.com>
Cc: Sachin P Sant <sachinp@linux.vnet.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
LKML-Reference: <20090721023226.31855.67236.sendpatchset@subratamodak.linux.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

In uv_setup_irq(), the call to create_irq() initially assigns
IRQ vectors to cpu 0. The subsequent call to
assign_irq_vector() in arch_enable_uv_irq() migrates the IRQ to
another cpu and frees the cpu 0 vector - at least it will be
freed as soon as the "IRQ move" completes.

arch_enable_uv_irq() needs to send a cleanup IPI to complete
the IRQ move. Otherwise, assignment of GRU interrupts on large
systems (>200 cpus) will exhaust the cpu 0 interrupt vectors
and initialization of the GRU driver will fail.
Signed-off-by: Jack Steiner <steiner@sgi.com>
LKML-Reference: <20090720142840.GA8885@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

With VMALLOC_END included in the calculation of MAXMEM (as of
2.6.28) it is no longer correct to also bump __VMALLOC_RESERVE
in reserve_top_address(). Doing so results in needlessly small
lowmem.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <4A71DD2A020000780000D482@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

One system has socket 1 come up as BSP.

kexeced kernel reports BSP as:

[    1.524550] Initializing cgroup subsys cpuacct
[    1.536064] initial_apicid:20
[    1.537135] ht_mask_width:1
[    1.538128] core_select_mask:f
[    1.539126] core_plus_mask_width:5
[    1.558479] CPU: Physical Processor ID: 0
[    1.559501] CPU: Processor Core ID: 0
[    1.560539] CPU: L1 I cache: 32K, L1 D cache: 32K
[    1.579098] CPU: L2 cache: 256K
[    1.580085] CPU: L3 cache: 24576K
[    1.581108] CPU 0/0x20 -> Node 0
[    1.596193] CPU 0 microcode level: 0xffff0008

It doesn't have correct physical processor id and will get an
error:

[   38.840859] CPU0 attaching sched-domain:
[   38.848287]  domain 0: span 0,8,72 level SIBLING
[   38.851151]   groups: 0 8 72
[   38.858137]   domain 1: span 0,8-15,72-79 level MC
[   38.868944]    groups: 0,8,72 9,73 10,74 11,75 12,76 13,77 14,78 15,79
[   38.881383] ERROR: parent span is not a superset of domain->span
[   38.890724]    domain 2: span 0-7,64-71 level CPU
[   38.899237] ERROR: domain->groups does not contain CPU0
[   38.909229]     groups: 8-15,72-79
[   38.912547] ERROR: groups don't span domain->span
[   38.919665]     domain 3: span 0-127 level NODE
[   38.930739]      groups: 0-7,64-71 8-15,72-79 16-23,80-87 24-31,88-95 32-39,96-103 40-47,104-111 48-55,112-119 56-63,120-127

it turns out: we can not use current_cpu_data in phys_pgd_id
for x2apic.

identify_boot_cpu() is called by check_bugs() before
smp_prepare_cpus() and till smp_prepare_cpus() current_cpu_data
for bsp is assigned with boot_cpu_data.

Just make phys_pkg_id for x2apic is aligned to xapic.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A6ADD0D.10002@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Change SGI UV default apicid mode to "physical". This is
required to match settings in the UV hub chip.
Signed-off-by: Jack Steiner <steiner@sgi.com>
LKML-Reference: <20090727143856.GA8905@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

The UV chipset automatically supplies the upper bits on nodes
being referenced by MMR accesses. These bit can be deleted from
the hub addressing macros.
Signed-off-by: Jack Steiner <steiner@sgi.com>
LKML-Reference: <20090727143808.GA8076@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

The UV BIOS has added additional MMR ranges that are mapped via
EFI virtual mode mappings. These ranges should be deleted from
ranges mapped by uv_system_init().
Signed-off-by: Jack Steiner <steiner@sgi.com>
Cc: linux-mm@kvack.org
LKML-Reference: <20090727143656.GA7698@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>