The current setting for SECTION_SIZE_BITS is quite small compared to
everyone else:

arch/powerpc/include/asm/sparsemem.h:#define SECTION_SIZE_BITS  24

arch/sparc/include/asm/sparsemem.h:#define SECTION_SIZE_BITS    30
arch/ia64/include/asm/sparsemem.h:#define SECTION_SIZE_BITS     (30)
arch/s390/include/asm/sparsemem.h:#define SECTION_SIZE_BITS     28
arch/x86/include/asm/sparsemem.h:# define SECTION_SIZE_BITS     27

And it has proven to be an issue during boot on very large machines.
If hotplug memory is enabled, drivers/base/memory.c does this:

       for (i = 0; i < NR_MEM_SECTIONS; i++) {
                if (!present_section_nr(i))
                        continue;
                err = add_memory_block(0, __nr_to_section(i), MEM_ONLINE,
                                        0, BOOT);
                if (!ret)
                        ret = err;
        }

Which creates a sysfs directory for every 16MB of memory. As a result
I'm seeing up to 30 minutes spent here during boot:

c000000000248ee0 .__sysfs_add_one+0x28/0x128
c0000000002492a8 .sysfs_add_one+0x38/0x188
c000000000249c88 .create_dir+0x70/0x138
c000000000249d98 .sysfs_create_dir+0x48/0x78
c00000000032bad8 .kobject_add_internal+0x140/0x308
c00000000032beb4 .kobject_init_and_add+0x4c/0x68
c00000000046c2c0 .sysdev_register+0xa0/0x220
c00000000047b1dc .add_memory_block+0x124/0x1e8
c0000000008d1f28 .memory_dev_init+0xf4/0x168
c0000000008d1b64 .driver_init+0x50/0x64
c000000000890378 .do_basic_setup+0x40/0xd4

I assume there are some O(n^2) issues in sysfs as we add all the memory
nodes. Bumping SECTION_SIZE_BITS to 256 MB drops the time to about 10
seconds and results in a much smaller /sys.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

We have had issues in the past with ibm,os-term initiating shutdown of a
partition. This is confusing to the user, especially if panic_timeout is
non zero.

The temporary fix was to avoid calling ibm,os-term if a panic_timeout was set
and since we set it on every boot we basically never call ibm,os-term.

An extended version of ibm,os-term has since been implemented which gives us
the behaviour we want:

  "When the platform supports extended ibm,os-term behavior, the return to the
  RTAS will always occur unless there is a kernel assisted dump active as
  initiated by an ibm,configure-kernel-dump call."

This patch checks for the ibm,extended-os-term property and calls ibm,os-term
if it exists.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

I noticed /proc/sys/vm/zone_reclaim_mode was 0 on a ppc64 NUMA box. It gets
enabled via this:

        /*
         * If another node is sufficiently far away then it is better
         * to reclaim pages in a zone before going off node.
         */
        if (distance > RECLAIM_DISTANCE)
                zone_reclaim_mode = 1;

Since we use the default value of 20 for REMOTE_DISTANCE and 20 for
RECLAIM_DISTANCE it never kicks in.

The local to remote bandwidth ratios can be quite large on System p
machines so it makes sense for us to reclaim clean pagecache locally before
going off node.

The patch below sets a smaller value for RECLAIM_DISTANCE and thus enables
zone reclaim.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Fix I2C-drivers which missed setting clientdata to NULL before freeing the
structure it points to. Also fix drivers which do this _after_ the structure
was freed already.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Colin Leroy <colin@colino.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Use set_cpus_allowed_ptr rather than set_cpus_allowed.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression E1,E2;
@@

- set_cpus_allowed(E1, cpumask_of_cpu(E2))
+ set_cpus_allowed_ptr(E1, cpumask_of(E2))

@@
expression E;
identifier I;
@@

- set_cpus_allowed(E, I)
+ set_cpus_allowed_ptr(E, &I)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

In some error handling cases the lock is not unlocked.

A simplified version of the semantic patch that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r exists@
expression E1;
identifier f;
@@

f (...) { <+...
* spin_lock_irqsave (E1,...);
... when != E1
* return ...;
...+> }
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Add an unlock before exiting the function.

A simplified version of the semantic patch that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r exists@
expression E1;
identifier f;
@@

f (...) { <+...
* spin_lock_irq (E1,...);
... when != E1
* return ...;
...+> }
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

kasprintf combines kmalloc and sprintf, and takes care of the size
calculation itself.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression a,flag;
expression list args;
statement S;
@@

  a =
-  \(kmalloc\|kzalloc\)(...,flag)
+  kasprintf(flag,args)
  <... when != a
  if (a == NULL || ...) S
  ...>
- sprintf(a,args);
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

dlpar_free_cc_nodes frees its argument, so dlpar_online_cpu should not be
called on the same value.  Skip over the call to dlpar_online_cpu by
jumping directly to out.

A simplified version of the semantic patch that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression E,E2;
@@

dlpar_free_cc_nodes(E)
...
(
  E = E2
|
* E
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The conditionals were testing different values, but then all freeing the
same one, which could result in a double free.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x,e;
identifier f;
iterator I;
statement S;
@@

*kfree(x);
... when != &x
    when != x = e
    when != I(x,...) S
*x
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Commit 0119536c, which added the assembly version of strncmp to
powerpc, mentions that it adds two instructions to the version from
boot/string.S to allow it to handle len=0. Unfortunately, it doesn't
always return 0 when that is the case. The length is passed in r5, but
the return value is passed back in r3. In certain cases, this will
happen to work. Otherwise it will pass back the address of the first
string as the return value.

This patch lifts the len <= 0 handling code from memcpy to handle that
case.

Reported by: Christian_Sellars@symantec.com
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
CC: <stable@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Fix minor nits found by cppcheck

[./macintosh/windfarm_pm81.c:760]: (style) Redundant condition. It is safe to deallocate a NULL pointer
[./macintosh/windfarm_pm81.c:762]: (style) Redundant condition. It is safe to deallocate a NULL pointer
Signed-off-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Fix minor nits found by cppcheck

[./arch/powerpc/platforms/powermac/low_i2c.c:594]: (style) The scope of the variable chans can be reduced
[./arch/powerpc/platforms/powermac/low_i2c.c:594]: (style) The scope of the variable i can be reduced
[./arch/powerpc/platforms/powermac/low_i2c.c:1260]: (style) Redundant condition. It is safe to deallocate a NULL pointer
Signed-off-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This avoids storing these registers in memory.
CPU6 errata will still use the old way.
Remove some G2 leftover accesses from 2.4
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Only the swap function cares about the ACCESSED bit in
the pte. Do not waste cycles updateting ACCESSED when swap
is not compiled into the kernel.
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Only modules will cause ITLB Misses as we always pin
the first 8MB of kernel memory.
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This removes a couple of insn's from the TLB Miss
handlers whithout changing functionality.
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Instead of referencing mem_map directly, use pfn_to_page. Otherwise
the kernel crashes when trying to start userspace if ARCH_PFN_OFFSET is
non-zero and CONFIG_BOOKE is not defined
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Add support for H_EM_GET_PARMS hcall that will return data
related to power modes from the platform.  Export the data
directly to user space for administrative tools to interpret
and use.

cat /proc/powerpc/lparcfg will export power mode data
Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Data address breakpoint exceptions are currently handled along with page-faults
which require interrupts to remain in enabled state. Since exception handling
for data breakpoints aren't pre-empt safe, we handle them separately.
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

BenH: Added to vio_cmo_dev_attrs as well

Provide a modalias entry for VIO devices in sysfs.  I believe
this was another initrd generation bugfix for anaconda.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

We can't just clear the user read permission in book3e pte, because
that will also clear supervisor read permission.  This surely isn't
desired.  Fix the problem by adding the supervisor read back.

BenH: Slightly simplified the ifdef and applied to ppc64 too
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The mpsc serial driver needx to set the port's device tree element
to register properly.
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The maple platform failed to load because it's firmware could not take a
link address of 0x4000000.  A new platform type with a link address of
0x400000 had to be created for the maple.
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This driver seems to be specific to a "Sky CPU" board for which we
don't appear to have upstream support (or not any more). No Kconfig
file in the kernel ever enables it. So remove it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

* 'urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6:
  pcmcia: fix up alignf issues

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

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  genirq: Force MSI irq handlers to run with interrupts disabled

* git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog:
  [WATCHDOG] hpwdt - fix lower timeout limit
  [WATCHDOG] iTCO_wdt: TCO Watchdog patch for additional Intel Cougar Point DeviceIDs
  [WATCHDOG] doc: Fix use of WDIOC_SETOPTIONS ioctl.
  [WATCHDOG] doc: watchdog simple example: don't fail on fsync()
  [WATCHDOG] set max63xx driver as ARM only
  [WATCHDOG] powerpc: pika_wdt ident cannot be const

* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
  libata: unlock HPA if device shrunk
  libata: disable NCQ on Crucial C300 SSD
  libata: don't whine on spurious IRQ

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (37 commits)
  smc91c92_cs: fix the problem of "Unable to find hardware address"
  r8169: clean up my printk uglyness
  net: Hook up cxgb4 to Kconfig and Makefile
  cxgb4: Add main driver file and driver Makefile
  cxgb4: Add remaining driver headers and L2T management
  cxgb4: Add packet queues and packet DMA code
  cxgb4: Add HW and FW support code
  cxgb4: Add register, message, and FW definitions
  netlabel: Fix several rcu_dereference() calls used without RCU read locks
  bonding: fix potential deadlock in bond_uninit()
  net: check the length of the socket address passed to connect(2)
  stmmac: add documentation for the driver.
  stmmac: fix kconfig for crc32 build error
  be2net: fix bug in vlan rx path for big endian architecture
  be2net: fix flashing on big endian architectures
  be2net: fix a bug in flashing the redboot section
  bonding: bond_xmit_roundrobin() fix
  drivers/net: Add missing unlock
  net: gianfar - align BD ring size console messages
  net: gianfar - initialize per-queue statistics
  ...

copy_to_user() returns the number of bytes left to be copied.

This was a typo from: d82ef020 "proc: pagemap: Hold mmap_sem during
page walk".
Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Some BIOSes don't configure HPA during boot but do so while resuming.
This causes harddrives to shrink during resume making libata detach
and reattach them.  This can be worked around by unlocking HPA if old
size equals native size.

Add ATA_DFLAG_UNLOCK_HPA so that HPA unlocking can be controlled
per-device and update ata_dev_revalidate() such that it sets
ATA_DFLAG_UNLOCK_HPA and fails with -EIO when the above condition is
detected.

This patch fixes the following bug.

  https://bugzilla.kernel.org/show_bug.cgi?id=15396Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Oleksandr Yermolenko <yaa.bta@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

Crucial said,

  Thank you for contacting us. We know that with our M225 line of SSDs
  you sometimes need to disable NCQ (native command queuing) to avoid
  just the type of errors you're seeing. Our recommendation for the
  M225 is to add libata.force=noncq to your Linux kernel boot options,
  under the kernel ATA library option.

  I have sent your feedback to the engineers working on the C300, and
  asked them to please pass it on to the firmware team. I have been
  notified that they are in the process of testing and finalizing a
  new firmware version, that you can expect to see released around the
  end of April. We’ll keep you posted as to when it will be available
  for download.

So, turn off NCQ on the drive w/ the current firmware revision.

Reported in the following bug.

  https://bugzilla.kernel.org/show_bug.cgi?id=15573Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: lethalwp@scarlet.be
Reported-by: Luke Macken <lmacken@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

On configurations where IRQ line is shared with a different
controller, spurious IRQs may happen continuously.  The message was
put there primarily for debugging anyway.  Kill it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

[Novell Bug 581103] HP Watchdog driver has arbitrary (wrong) timeout limits.
Fix the lower timeout limit to a more appropriate value.
Signed-off-by: Thomas Mingarelli <Thomas.Mingarelli@hp.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: stable <stable@kernel.org>

This patch adds the Intel Cougar Point PCH LPC Controller DeviceIDs for iTCO Watchdog.
Signed-off-by: Seth Heasley <seth.heasley@intel.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: stable <stable@kernel.org>

In the watchdog-test program and watchdog-api.txt, pass the values to
the WDIOC_SETOPTIONS ioctl as a pointer to an integer containing the
values intead of directly in the third ioctl argument. The actual
watchdog drivers in drivers/watchdog don't read the options directly
from the argument but use get_user and copy_from_user.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Module refcounting is implemented with a per-cpu counter for speed.
However there is a race when tallying the counter where a reference may
be taken by one CPU and released by another.  Reference count summation
may then see the decrement without having seen the previous increment,
leading to lower than expected count.  A module which never has its
actual reference drop below 1 may return a reference count of 0 due to
this race.

Module removal generally runs under stop_machine, which prevents this
race causing bugs due to removal of in-use modules.  However there are
other real bugs in module.c code and driver code (module_refcount is
exported) where the callers do not run under stop_machine.

Fix this by maintaining running per-cpu counters for the number of
module refcount increments and the number of refcount decrements.  The
increments are tallied after the decrements, so any decrement seen will
always have its corresponding increment counted.  The final refcount is
the difference of the total increments and decrements, preventing a
low-refcount from being returned.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6:
  [SCSI] qla1280: retain firmware for error recovery
  [SCSI] attirbute_container: Initialize sysfs attributes with sysfs_attr_init
  [SCSI] advansys: fix regression with request_firmware change
  [SCSI] qla2xxx: Updated version number to 8.03.02-k2.
  [SCSI] qla2xxx: Prevent sending mbx commands from sysfs during isp reset.
  [SCSI] qla2xxx: Disable MSI on qla24xx chips other than QLA2432.
  [SCSI] qla2xxx: Check to make sure multique and CPU affinity support is not enabled at the same time.
  [SCSI] qla2xxx: Correct vp_idx checking during PORT_UPDATE processing.
  [SCSI] qla2xxx: Honour "Extended BB credits" bit for CNAs.
  [SCSI] scsi_transport_fc: Make sure commands are completed when rport is offline
  [SCSI] libiscsi: Fix recovery slowdown regression