Current code assumed that devices were directly connected to a Calgary
bridge, as it tried to get the iommu table directly from the parent bus
controller.

When we have another bridge between the Calgary/CalIOC2 bridge and the
device we should look upwards until we get to the top (Calgary/CalIOC2
bridge), where the iommu table resides.
Signed-off-by: NMurillo Fernandes Bernardes <mfb@br.ibm.com>
Signed-off-by: NMuli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some broken devices have been discovered to require %al/%ax/%eax registers
for MMIO config space accesses.  Modify mmconfig.c to use these registers
explicitly (rather than modify the global readb/writeb/etc inlines).

AK: also changed i386 to always use eax
AK: moved change to extended space probing to different patch
AK: reworked with inlines according to Linus' requirements.
AK: improve comments.
Signed-off-by: Ndean gaudet <dean@arctic.org>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There are some parts of include/asm-generic/pgtable.h that are relevant to
the non-mmu architectures.  To make it easier to include this from them I
would like to ifdef the relevant parts.

Without this there is a handful of functions that are referenced in here
that are not defined on many non-mmu architectures.  They could be defined
out of course, as an alternative approach.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch finishes the i386 and x86-64 ->sysdata conversion and hopefully
also fixes Riku's and Andy's observed bugs.  It is based on Yinghai Lu's
and Andy Whitcroft's patches (thanks!) with some changes:

- introduce pci_scan_bus_with_sysdata() and use it instead of
  pci_scan_bus() where appropriate. pci_scan_bus_with_sysdata() will
  allocate the sysdata structure and then call pci_scan_bus().
- always allocate pci_sysdata dynamically. The whole point of this
  sysdata work is to make it easy to do root-bus specific things
  (e.g., support PCI domains and IOMMU's). I dislike using a default
  struct pci_sysdata in some places and a dynamically allocated
  pci_sysdata elsewhere - the potential for someone indavertantly
  changing the default structure is too high.
- this patch only makes the minimal changes necessary, i.e., the NUMA node is
  always initialized to -1. Patches to do the right thing with regards
  to the NUMA node can build on top of this (either add a 'node'
  parameter to pci_scan_bus_with_sysdata() or just update the node
  when it becomes known).

The patch was compile tested with various configurations (e.g., NUMAQ,
VISWS) and run-time tested on i386 and x86-64.  Unfortunately none of my
machines exhibited the bugs so caveat emptor.

Andy, could you please see if this fixes the NUMA issues you've seen?
Riku, does this fix "pci=noacpi" on your laptop?
Signed-off-by: NMuli Ben-Yehuda <muli@il.ibm.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Chuck Ebbert <cebbert@redhat.com>
Cc: <riku.seppala@kymp.net>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Minor docbook error since argument name in comment doesn't match function
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This code corrects the usage of the request_irq() routine.
Signed-off-by: NJay Estabrook <jay.estabrook@hp.com>
Signed-off-by: NIvan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Files using bits from paravirt.h should explicitly include it rather than
relying on it being pulled in by something else.
Signed-off-by: NJes Sorensen <jes@sgi.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

gcc-4.2 is a lot more picky about its symbol handling.  EXPORT_SYMBOL no
longer works on symbols that are undefined or defined with static scope.

For example, with CONFIG_PROFILE off, I see:

  kernel/profile.c:206: error: __ksymtab_profile_event_unregister causes a section type conflict
  kernel/profile.c:205: error: __ksymtab_profile_event_register causes a section type conflict

This patch moves the EXPORTs inside the #ifdef CONFIG_PROFILE, so we
only try to export symbols that are defined.

Also, in kernel/kprobes.c there's an EXPORT_SYMBOL_GPL() for
jprobes_return, which if CONFIG_JPROBES is undefined is a static
inline and gives the same error.

And in drivers/acpi/resources/rsxface.c, there's an
ACPI_EXPORT_SYMBOPL() for a static symbol. If it's static, it's not
accessible from outside the compilation unit, so should bot be exported.

These three changes allow building a zx1_defconfig kernel with gcc 4.2
on IA64.

[akpm@linux-foundation.org: export jpobe_return properly]
Signed-off-by: NPeter Chubb <peterc@gelato.unsw.edu.au>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I find a function(clockevents_unregister_notifier) which is not called by
anything in tree.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Git rid of "warning: passing arg 2 of `access_ok' makes pointer from integer
without a cast" reported on SH ...  most architectures use macros in that
test, SH uses inlined functions.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

scripts/kconfig/conf -d arch/cris/Kconfig
arch/cris/Kconfig:183: can't open file "drivers/cdrom/Kconfig"
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Cc: Mikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

synchronize_idle() sounds like an interesting function, but we don't
actually have it, so don't prototype it.  Introduced in commit
9b06e818, in 2005.
Signed-off-by: NJosh Triplett <josh@kernel.org>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add missing "const" qualifiers to the print_hex_dump_bytes() library routines.

(akpm: rumoured to fix some compile warning somewhere)
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

sh:

drivers/mtd/mtdchar.c: In function `mtd_mmap':
drivers/mtd/mtdchar.c:817: error: dereferencing pointer to incomplete type
drivers/mtd/mtdchar.c:817: error: `VM_SHARED' undeclared (first use in this function)
drivers/mtd/mtdchar.c:817: error: (Each undeclared identifier is reported only once

Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Patch c5c34d48 (tty: flush flip buffer on
ldisc input queue flush) introduces a race condition which can lead to memory
leaks.

The problem can be triggered when tcflush() is called when data are being
pushed to the line discipline driver by flush_to_ldisc().

flush_to_ldisc() releases tty->buf.lock when calling the line discipline
receive_buf function. At that poing tty_buffer_flush() kicks in and sets both
tty->buf.head and tty->buf.tail to NULL. When flush_to_ldisc() finishes, it
restores tty->buf.head but doesn't touch tty->buf.tail. This corrups the
buffer queue, and the next call to tty_buffer_request_room() will allocate a
new buffer and overwrite tty->buf.head. The previous buffer is then lost
forever without being released.

(Thanks to Laurent for the above text, for finding, disgnosing and reporting
the bug)

- Use tty->flags bits for the flush status.

- Wait for the flag to clear again before returning

- Fix the doc error noted

- Fix flush of empty queue leaving stale flushpending

[akpm@linux-foundation.org: cleanup]
Signed-off-by: NAlan Cox <alan@redhat.com>
Acked-by: NPaul Fulghum <paulkf@microgate.com>
Cc: Laurent Pinchart <laurentp@cse-semaphore.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A warning note from Sam Ravnborg about kconfig's select evilness,
dependencies and the future (slightly corrected).
Signed-off-by: NJarek Poplawski <jarkao2@o2.pl>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In Documentation/sysrq.txt, the description of 'h' says that any key not
listed *above* will generate help.  That's obviously not true since all the
keys listed below 'h' will do what they are described to do, not display help.
 So change the text so that it says that any key not listed in the table will
generate help, which is what really happens.
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This version brings a number of new checks, and a number of bug
fixes.  Of note:

  - checks for spacing on round and square bracket combinations
  - loosening of the single statement brace checks, to allow
    them when they contain comments or where other blocks in a
    compound statement have them.
  - parks the multple declaration support
  - allows architecture defines in architecture specific headers

Andy Whitcroft (21):
      Version: 0.09
      loosen single statement brace checks
      fix up multiple declaration to avoid function arguments
      add some function space parenthesis check exceptions
      handle EXPORT_'s with parentheses in their names
      clean up some warnings in multi-line macro bracketing support
      park the multiple declaration checks
      make block brace checks count comments as a statement
      __volatile__ and __extension__ are not functions
      allow architecture specific defined within architecture includes
      check spacing on square brackets
      check spacing on parentheses
      ensure we apply checks to the part before start comment
      check #ifdef conditional spacing
      handle __init_refok and __must_check
      add noinline to inline checks
      prevent email addresses from tripping spacing checks
      handle typed initialiser spacing
      handle line contination as end of line
      add bool to the type matcher
      refine EXPORT_SYMBOL checks to handle pointers
Signed-off-by: NAndy Whitcroft <apw@shadowen.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Long ago I've noticed (but didn't pay much attention) that
spi_mpc83xx using PM calculations that differs from what
specs describe. I.e.

u8 pm = mpc83xx_spi->spibrg / (spi->max_speed_hz * 4);

While specs says: "The SPI baud rate generator clock source (either
system clock or system clock divided by 16, depending on DIV16 bit) is
divided by 4 * ([PM] + 1), a range from 4 to 64.".

Thus " - 1" is missing in the spi_mpc83xx's formula.

Why nobody noticed that bug? Probably because sysclk usually less then
user expects, e.g. you expect 200 MHz, but real clock is 198 MHz,
and integer rounding helps when this formula is used.

Suppose it's SPI in QE, SYSCLK at 198 MHz, thus SPIBRG at 99MHz, 25 MHz
requested.

PM = (99MHz / ( 25 MHz * 4 )), PM == 0, output SPICLK will be 24.75 MHz

At lower frequencies this bug is more noticeable, though.

And this bug shows itself in all its beauty if SYSCLK is equal or a bit
more than you expect (200 MHz SYSCLK, 100 MHz SPIBRG):
PM = (100MHz / ( 25 MHz * 4 )), PM == 1, output SPICLK will be 12.625 MHz!
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

For MPC8349E input to the SPI Baud Rate Generator is SYSCLK, but it's
SYSCLK/2 for MPC8323E (SPI in QE).  Fix this, and remove confusion by
renaming the mpc83xx_spi->sysclk member as mpc83xx_spi->spibrg.
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Documentation/watchdog/watchdog.txt does not exist, it is Documentation/watchdog/wdt.txt
Signed-off-by: NGabriel Craciunescu <nix.or.die@googlemail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is add a document for memory hotplug to describe "How to use" and
"Current status".
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NYasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

cm4000_cs.c and cm4040_cs.c call the internal release function with
an argument of wrong type. this fixes bug #8485
Signed-off-by: NDaniel Ritz <daniel.ritz@gmx.ch>
Cc: Bill McConnaughey <mcconnau@biochem.wustl.edu>
Cc: Natalie Protasevich <protasnb@gmail.com>
Cc: Harald Welte <laforge@gnumonks.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On some systems some PFNs reported by the early initialization code as
'nosave' may be invalid.  If we try to set the corresponding bits in the
hibernation bitmap, BUG_ON() in memory_bm_find_bit() will be triggered and
the system won't be able to boot (cf.
https://bugzilla.novell.com/show_bug.cgi?id=296242).

Prevent this from happening by verifying if the 'nosave' PFNs are valid in
mark_nosave_pages().
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ecryptfs_init() exits without doing any cleanup jobs if
ecryptfs_init_messaging() fails.  In that case, eCryptfs leaves
sysfs entries, leaks memory, and causes an invalid page fault.
This patch fixes the problem.
Signed-off-by: NRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: NMichael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NGabriel Craciunescu <nix.or.die@googlemail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

After /proc/sys rewrite it was left unused.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Misplaced #endif is hiding the numa_zonelist_order sysctl when !SECURITY.
Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When ecryptfs_lookup() is called against special files, eCryptfs generates
the following errors because it tries to treat them like regular eCryptfs
files.

Error opening lower file for lower_dentry [0xffff810233a6f150], lower_mnt [0xffff810235bb4c80], and flags
[0x8000]
Error opening lower_file to read header region
Error attempting to read the [user.ecryptfs] xattr from the lower file; return value = [-95]
Valid metadata not found in header region or xattr region; treating file as unencrypted

For instance, the problem can be reproduced by the steps below.

  # mkdir /root/crypt /mnt/crypt
  # mount -t ecryptfs /root/crypt /mnt/crypt
  # mknod /mnt/crypt/c0 c 0 0
  # umount /mnt/crypt
  # mount -t ecryptfs /root/crypt /mnt/crypt
  # ls -l /mnt/crypt

This patch fixes it by adding a check similar to directories and
symlinks.
Signed-off-by: NRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: NMichael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Connect up the fallocate() system call.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This builds upon my previous attempts to resolve some jitter problems seen
with the Matrox G450 and G550 -based cards, including odd disparities observed
between x86 and Power -based machines in a somewhat less hackish way (removing
the hacked ifdefs).

Apparently, preference should be given to use the DVI PLL when frequencies
permit, the Standard PLL otherwise.  The max pixel clock for the panellink
interface is extracted from the PInS information on the card and used as a
limit to determine which PLL to use.
Signed-off-by: NPaul A. Clarke <pc@us.ibm.com>
Acked-by: NPetr Vandrovec <petr@vandrovec.name>
Signed-off-by: NAntonino Daplas <adaplas@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The current version is very old and does not correctly specify how to
set the video mode.

Signed-off by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Signed-off-by: NAntonino Daplas <adaplas@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

- better handling of the pvr2 registers based on more up to date information.

Testing shows that it seems to work pretty well at 16bpp, 24bpp and 32bpp -
including proper rendering of the boot logo at all levels (previously this was
a bit broken even at 16bpp) and giving white against black text.  Really
detailed testing (eg with X11) requires support for the maple bus - which
isn't (currently - next project assuming this is okay) available, but I have
no reason to think this is broken.

Signed-off by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Acked-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NAntonino Daplas <adaplas@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Reported by: Adrian McMenamin <adrianmcmenamin@gmail.com>

This driver will oops when the pseudo_palette[] is written as u32 but not when
written as u16.  When written as u32, it corrupts the adjacent 'mmio_base'
field of struct pvr2fb_par.  Fix by using framebuffer_alloc()/release() to
allocate struct fb_info and struct pvr2fb_par, and create the pseudo_palette[]
as part of struct pvr2fb_par.
Signed-off-by: NAntonino Daplas <adaplas@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix compile warning ('map_override unused') if fbcon is compiled as a module
and CONFIG_FRAMEBUFFER_CONSOLE_DETECT_PRIMARY=n.

[akpm@linux-foundation.org: cleanup]
Signed-off-by: NAntonino Daplas <adaplas@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Visualize-EG, Graffiti and A4450A graphics cards on PARISC can
be configured in double-buffer and standard mode, but the stifb
driver supports standard mode only.
This patch detects double-buffered cards more reliable.

It is a real bugfix for a very nasty problem for all parisc users which have
wrongly configured their graphic card.  The problem: The stifb graphics driver
will not detect that the card is wrongly configured and then nevertheless just
enables the graphics mode, which it shouldn't.  In the end, the user will see
no further updates / boot messages on the screen.

We had documented this problem already on our FAQ
(http://parisc-linux.org/faq/index.html#viseg "Why do I get corrupted graphics
with my Vis-EG/Graffiti/A4450A card?") but people still run into this problem.
 So having this fix in as early as possible can help us.
Signed-off-by: NHelge Deller <deller@gmx.de>
Signed-off-by: NAntonino Daplas <adaplas@gmail.com>
Cc: <stable@kernel.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Need to initialize map_bh.b_state to zero.  Otherwise, in case of a faulty
user-buffer its possible to go into dio_zero_block() and submit a page by
mistake - since it checks for buffer_new().

http://marc.info/?l=linux-kernel&m=118551339032528&w=2

akpm: Linus had a (better) patch to just do a kzalloc() in there, but it got
lost.  Probably this version is better for -stable anwyay.
Signed-off-by: NBadari Pulavarty <pbadari@us.ibm.com>
Acked-by: NJoe Jin <joe.jin@oracle.com>
Acked-by: NZach Brown <zach.brown@oracle.com>
Cc: gurudas pai <gurudas.pai@oracle.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I have had four seperate system lockups attributable to this exact problem
in two days of testing.  Instead of trying to handle all the weird end
cases and wrap, how about changing it to look for exactly what we appear
to want.

The following patch removes a couple races in setup_APIC_timer.  One occurs
when the HPET advances the COUNTER past the T0_CMP value between the time
the T0_CMP was originally read and when COUNTER is read.  This results in
a delay waiting for the counter to wrap.  The other results from the counter
wrapping.

This change takes a snapshot of T0_CMP at the beginning of the loop and
simply loops until T0_CMP has changed (a tick has happened).

<later>

I have one small concern about the patch.  I am not sure it meets the intent
as well as it should.  I think we are trying to match APIC timer interrupts up
with the hpet counter increment.  The event which appears to be disturbing
this loop in our test environment is the NMI watchdog.  What we believe has
been happening with the existing code is the setup_APIC_timer loop has read
the CMP value, and the NMI watchdog code fires for the first time.  This
results in a series of icache miss slowdowns and by the time we get back to
things it has wrapped.

I think this code is trying to get the CMP as close to the counter value as
possible.  If that is the intent, maybe we should really be testing against a
"window" around the CMP.  Something like COUNTER = CMP+/2.  It appears COUNTER
should get advanced every 89nSec (IIRC).  The above seems like an unreasonably
small window, but may be necessary.  Without documentation, I am not sure of
the original intent with this code.

In summary, this code fixes my boot hangs, but since I am not certain of the
intent of the existing code, I am not certain this has not introduced new bugs
or unexpected behaviors.
Signed-off-by: NRobin Holt <holt@sgi.com>
Acked-by: NAndi Kleen <ak@suse.de>
Cc: Vojtech Pavlik <vojtech@suse.cz>
Cc: "Aaron Durbin" <adurbin@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There's a little problem in Documentation/vm/slabinfo.c
The code is using "%d" in a printf() call to print an 'unsigned long'.
This patch corrects it to use "%lu" instead.
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: NChristoph Lameter <clameter@sgi.com>