Impact: Fix cpu offline when CONFIG_MAXSMP=y

Changeset bc9b83dd "cpumask: convert
c1e_mask in arch/x86/kernel/process.c to cpumask_var_t" contained a
bug: c1e_mask is manipulated even if C1E isn't detected (and hence
not allocated).

This is simply fixed by checking for NULL (which gcc optimizes out
anyway of CONFIG_CPUMASK_OFFSTACK=n, since it knows ce1_mask can never
be NULL).

In addition, fix a leak where select_idle_routine re-allocates
(and re-clears) c1e_mask on every cpu init.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Mike Travis <travis@sgi.com>
LKML-Reference: <200903171450.34549.rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: cleanup, potential bugfix

Not sure what changed to expose this, but clearly that numa_node_id()
doesn't belong in mmzone.h (the inline in gfp.h is probably overkill, too).

In file included from include/linux/topology.h:34,
                 from arch/x86/mm/numa.c:2:
/home/rusty/patches-cpumask/linux-2.6/arch/x86/include/asm/topology.h:64:1: warning: "numa_node_id" redefined
In file included from include/linux/topology.h:32,
                 from arch/x86/mm/numa.c:2:
include/linux/mmzone.h:770:1: warning: this is the location of the previous definition
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Mike Travis <travis@sgi.com>
LKML-Reference: <200903132343.37661.rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: fix (CONFIG_MAXSMP=y only) boot crash

c032ef60 "cpumask: convert
node_to_cpumask_map[] to cpumask_var_t" didn't get this one
conversion.  There was a compile warning, but I missed it.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Mike Travis <travis@sgi.com>
LKML-Reference: <200903132342.42813.rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Merge branch 'cpus4096' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-x86 into cpus4096

Impact: cleanup

We are removing cpumask_t in favour of struct cpumask: mainly as a
marker of what code is now CONFIG_CPUMASK_OFFSTACK-safe.

The only non-trivial change here is vector_allocation_domain():
explicitly clear the mask and set the first word, rather than using
assignment.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: remove cpumask_t, reduce per-cpu size for CONFIG_CPUMASK_OFFSTACK=y
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: cleanup

It's not legal to do assignments into cpumask_var_t; they will soon be of
variable length.

So explicitly clear the mask and set the first word, rather than using
assignment.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: cleanup

In particular, *map are deprecated, and you have to use the accessors
as *mask are const.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
To: Jeremy Fitzhardinge <jeremy@xensource.com>

Impact: cleanup, remove cpumask from stack

summit_send_IPI_allbutself might as well call
default_send_IPI_mask_allbutself_logical().  Also change cpumask_t to
struct cpumask and &cpu_online_map to cpu_online_mask while here.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: cleanup

1) &cpu_online_map -> cpu_online_mask
2) first_cpu/next_cpu_nr -> cpumask_first/cpumask_next
3) cpu_*_map manipulation -> init_cpu_* / set_cpu_*
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: cleanup
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: reduce kernel memory usage when CONFIG_CPUMASK_OFFSTACK=y
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: reduce kernel memory usage when CONFIG_CPUMASK_OFFSTACK=y

Straightforward conversion: done for 32 and 64 bit kernels.
node_to_cpumask_map is now a cpumask_var_t array.

64-bit used to be a dynamic cpumask_t array, and 32-bit used to be a
static cpumask_t array.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: cleanup

We take the 64-bit code and use it on 32-bit as well.  The new file
is called mm/numa.c.

In a minor cleanup, we use cpu_none_mask instead of declaring a local
cpu_mask_none.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: cleanup
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: implement new API

We define arch_send_call_function_ipi_mask and generic kernel/smp.c
code creates arch_send_call_function_ipi() as a wrapper.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: reduce kernel memory usage when CONFIG_CPUMASK_OFFSTACK=y

Simple conversion of mce_device_initialized to cpumask_var_t.  We don't
check the alloc_cpumask_var() return since it's boot-time only, and
the misc_register() in that same function isn't checked.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: reduce per-cpu size for CONFIG_CPUMASK_OFFSTACK=y

In most places it's cleaner to use the accessors cpu_sibling_mask()
and cpu_core_mask() wrappers which already exist.

I couldn't avoid cleaning up the access in oprofile, either.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: cleanup, reduce memory usage for CONFIG_CPUMASK_OFFSTACK=y

I *think* every path calls check_nmi_watchdog before using the
watchdog, so that's the right place for the initialization.

If that's wrong, we'll get a nice NULL-deref with
CONFIG_CPUMASK_OFFSTACK=y, and have uncovered another bug.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: reduce kernel size when CONFIG_CPUMASK_OFFSTACK=y

Simple conversion.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: cleanup

There were replaced by topology_core_cpumask and topology_thread_cpumask.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: cleanup

cpu_coregroup_mask is the New Hotness.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: reduce stack usage for large NR_CPUS

cpumask_of_pcibus() is the new version.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: cleanup

(Thanks to Al Viro for reminding me of this, via Ingo)

CPU_MASK_ALL is the (deprecated) "all bits set" cpumask, defined as so:

	#define CPU_MASK_ALL (cpumask_t) { { ... } }

Taking the address of such a temporary is questionable at best,
unfortunately 321a8e9d (cpumask: add CPU_MASK_ALL_PTR macro) added
CPU_MASK_ALL_PTR:

	#define CPU_MASK_ALL_PTR (&CPU_MASK_ALL)

Which formalizes this practice.  One day gcc could bite us over this
usage (though we seem to have gotten away with it so far).

So replace everywhere which used &CPU_MASK_ALL or CPU_MASK_ALL_PTR
with the modern "cpu_all_mask" (a real const struct cpumask *), and remove
CPU_MASK_ALL_PTR altogether.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Ingo Molnar <mingo@elte.hu>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mike Travis <travis@sgi.com>

Impact: cleanup

node_to_cpumask (and the blecherous node_to_cpumask_ptr which
contained a declaration) are replaced now everyone implements
cpumask_of_node.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Impact: cleanup

This is presumably what those definitions are for, and while all archs
define cpu_core_map/cpu_sibling map, that's changing (eg. x86 wants to
change it to a pointer).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Guennadi Liakhovetski noticed that the end condition for the loop in
bitmap_find_free_region() is wrong, and the "return if error" was also
using the wrong conditional that would only trigger if the bitmap was an
exact multiple of the allocation size, which is not necessarily the case
with dma_alloc_from_coherent().

Such a failure would end up in bitmap_find_free_region() accessing
beyond the end of the bitmap.
Reported-by: Guennadi Liakhovetski <lg@denx.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fixes:
  kbuild: remove unused -r option for module-init-tool depmod
  kbuild: fix 'make rpm' when CONFIG_LOCALVERSION_AUTO=y and using SCM tree
  kbuild: fix mkspec to cleanup RPM_BUILD_ROOT
  kbuild: fix C libary confusion in unifdef.c due to getline()

* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  cpumask: mm_cpumask for accessing the struct mm_struct's cpu_vm_mask.
  cpumask: tsk_cpumask for accessing the struct task_struct's cpus_allowed.

* git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus:
  Squashfs: Valid filesystems are flagged as bad by the corrupted fs patch

* 'hwmon-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6:
  hwmon: (f75375s) Remove unnecessary and confusing initialization
  hwmon: (it87) Properly decode -128 degrees C temperature
  hwmon: (lm90) Document support for the MAX6648/6692 chips
  hwmon: (abituguru3) Fix I/O error handling

Trivial patch to fix bad links in the ext2 and ext3 documentation.
Signed-off-by: Jody McIntyre <scjody@sun.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'fixes-20090312' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/pci:
  PCIe: portdrv: call pci_disable_device during remove
  pci: Fix typo in message while disabling HT MSI mapping
  pci: don't disable too many HT MSI mapping
  powerpc/pseries: The RPA PCI hotplug driver depends on EEH
  PCIe: AER: during disable, check subordinate before walking
  PCI: Add PCI quirk to disable L0s ASPM state for 82575 and 82598

STag zero is a special STag that allows consumers to access any bus
address without registering memory.  The nes driver unfortunately
allows STag zero to be used even with QPs created by unprivileged
userspace consumers, which means that any process with direct verbs
access to the nes device can read and write any memory accessible to
the underlying PCI device (usually any memory in the system).  Such
access is usually given for cluster software such as MPI to use, so
this is a local privilege escalation bug on most systems running this
driver.

The driver was using STag zero to receive the last streaming mode
data; to allow STag zero to be disabled for unprivileged QPs, the
driver now registers a special MR for this data.

Cc: <stable@kernel.org>
Signed-off-by: Faisal Latif <faisal.latif@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

There was a report of a data corruption
http://lkml.org/lkml/2008/11/14/121.  There is a script included to
reproduce the problem.

During testing, I encountered a number of strange things with ext3, so I
tried ext2 to attempt to reduce complexity of the problem.  I found that
fsstress would quickly hang in wait_on_inode, waiting for I_LOCK to be
cleared, even though instrumentation showed that unlock_new_inode had
already been called for that inode.  This points to memory scribble, or
synchronisation problme.

i_state of I_NEW inodes is not protected by inode_lock because other
processes are not supposed to touch them until I_LOCK (and I_NEW) is
cleared.  Adding WARN_ON(inode->i_state & I_NEW) to sites where we modify
i_state revealed that generic_sync_sb_inodes is picking up new inodes from
the inode lists and passing them to __writeback_single_inode without
waiting for I_NEW.  Subsequently modifying i_state causes corruption.  In
my case it would look like this:

CPU0                            CPU1
unlock_new_inode()              __sync_single_inode()
 reg <- inode->i_state
 reg -> reg & ~(I_LOCK|I_NEW)   reg <- inode->i_state
 reg -> inode->i_state          reg -> reg | I_SYNC
                                reg -> inode->i_state

Non-atomic RMW on CPU1 overwrites CPU0 store and sets I_LOCK|I_NEW again.

Fix for this is rather than wait for I_NEW inodes, just skip over them:
inodes concurrently being created are not subject to data integrity
operations, and should not significantly contribute to dirty memory
either.

After this change, I'm unable to reproduce any of the added warnings or
hangs after ~1hour of running.  Previously, the new warnings would start
immediately and hang would happen in under 5 minutes.

I'm also testing on ext3 now, and so far no problems there either.  I
don't know whether this fixes the problem reported above, but it fixes a
real problem for me.

Cc: "Jorge Boncompte [DTI2]" <jorge@dti2.net>
Reported-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Cc: Jan Kara <jack@suse.cz>
Cc: <stable@kernel.org>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Even when page reclaim is under mem_cgroup, # of scan page is determined by
status of global LRU. Fix that.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

No software visible difference from revision A.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Samuel Ortiz <sameo@openedhand.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Currently we disable the Acer WMI backlight device if there is no ACPI
backlight device.  As a result, we end up with no backlight device at all.
 We should instead disable it if there is an ACPI device, as the other
laptop drivers do.  This regression was introduced in febf2d95 ("Acer-WMI:
fingers off backlight if video.ko is serving this functionality").

Each laptop driver with backlight support got a similar change around
febf2d95.  The changes to the other drivers look correct; see e.g.
a598c82f for a similar but correct change.  The regression is also in
2.6.28.
Signed-off-by: Michael Spang <mspang@csclub.uwaterloo.ca>
Acked-by: Thomas Renninger <trenn@suse.de>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Carlos Corbacho <carlos@strangeworlds.co.uk>
Cc: Len Brown <len.brown@intel.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: <stable@kernel.org>		[2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>