Many laptops have problems with ticking the local APIC timer in C2/C3.
The code added earlier to use it by default on ATI didn't really work
for them. Don't enable it when the system supports C2/C3.

This doesn't fix the problem fully, but at least it's not worse than before.
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This caused a sigreturn with bad argument on a preemptible kernel
to complain with

Debug: sleeping function called from invalid context at /home/lsrc/quilt/linux/include/linux/rwsem.h:43
in_atomic():0, irqs_disabled():1

Call Trace: {__might_sleep+190} {profile_task_exit+21}
       {__do_exit+34} {do_wait+0}
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

AMD SimNow!'s JIT doesn't like them at all in the guest. For distribution
installation it's easiest if it's a boot time option.

Also I moved the variable to a more appropiate place and make
it independent from sysctl

And marked __read_mostly which it is.
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Along with that, also suppress the memory touching altogether when the
watchdog is not running, to eliminate needless crosstalk. Plus ad a call
to it to make things consistent (one could also consider removing the call
in enable_timer_nmi_watchdog()).
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

... and enable 1394 by default.
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The early initialization of cpu_to_node code as it is now only updates the
cpu_to_node array, and does not update cpu_pda()->nodemember.  This will
cause numa_node_id() to return 0 on systems where CPU 0 is not on Node 0.
This leads to a kernel panic in slab.c.

I've tested the patch below on a 16 processor x86_64 ES7000-600 server, and
no longer see the panic I saw with the original 2.6.16-rc3.
Signed-off-by: NDan Yeisley <dan.yeisley@unisys.com>
Acked-by: NAndi Kleen <ak@muc.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add some more gitignore files for i386 architecture.  This files are
created during the build process of a i386 kernel.
Signed-off-by: NThomas Meyer <thomas@m3y3r.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This path isn't obvious.  It looks as if the kernel will be taking three
args from the user stack, but it only takes one from there.
Signed-off-by: NAlbert Cahalan <acahalan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Make the FRV arch use virtual interrupt disablement because accesses to the
processor status register (PSR) are relatively slow and because we will
soon have the need to deal with multiple interrupt controls at the same
time (separate h/w and inter-core interrupts).

The way this is done is to dedicate one of the four integer condition code
registers (ICC2) to maintaining a virtual interrupt disablement state
whilst inside the kernel.  This uses the ICC2.Z flag (Zero) to indicate
whether the interrupts are virtually disabled and the ICC2.C flag (Carry)
to indicate whether the interrupts are physically disabled.

ICC2.Z is set to indicate interrupts are virtually disabled.  ICC2.C is set
to indicate interrupts are physically enabled.  Under normal running
conditions Z==0 and C==1.

Disabling interrupts with local_irq_disable() doesn't then actually
physically disable interrupts - it merely sets ICC2.Z to 1.  Should an
interrupt then happen, the exception prologue will note ICC2.Z is set and
branch out of line using one instruction (an unlikely BEQ).  Here it will
physically disable interrupts and clear ICC2.C.

When it comes time to enable interrupts (local_irq_enable()), this simply
clears the ICC2.Z flag and invokes a trap #2 if both Z and C flags are
clear (the HI integer condition).  This can be done with the TIHI
conditional trap instruction.

The trap then physically reenables interrupts and sets ICC2.C again.  Upon
returning the interrupt will be taken as interrupts will then be enabled.
Note that whilst processing the trap, the whole exceptions system is
disabled, and so an interrupt can't happen till it returns.

If no pending interrupt had happened, ICC2.C would still be set, the HI
condition would not be fulfilled, and no trap will happen.

Saving interrupts (local_irq_save) is simply a matter of pulling the ICC2.Z
flag out of the CCR register, shifting it down and masking it off.  This
gives a result of 0 if interrupts were enabled and 1 if they weren't.

Restoring interrupts (local_irq_restore) is then a matter of taking the
saved value mentioned previously and XOR'ing it against 1.  If it was one,
the result will be zero, and if it was zero the result will be non-zero.
This result is then used to affect the ICC2.Z flag directly (it is a
condition code flag after all).  An XOR instruction does not affect the
Carry flag, and so that bit of state is unchanged.  The two flags can then
be sampled to see if they're both zero using the trap (TIHI) as for the
unconditional reenablement (local_irq_enable).

This patch also:

 (1) Modifies the debugging stub (break.S) to handle single-stepping crossing
     into the trap #2 handler and into virtually disabled interrupts.

 (2) Removes superseded fixup pointers from the second instructions in the trap
     tables (there's no a separate fixup table for this).

 (3) Declares the trap #3 vector for use in .org directives in the trap table.

 (4) Moves irq_enter() and irq_exit() in do_IRQ() to avoid problems with
     virtual interrupt handling, and removes the duplicate code that has now
     been folded into irq_exit() (softirq and preemption handling).

 (5) Tells the compiler in the arch Makefile that ICC2 is now reserved.

 (6) Documents the in-kernel ABI, including the virtual interrupts.

 (7) Renames the old irq management functions to different names.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Make various alterations and fixes to the FRV arch:

 (1) Resyncs the FRV system call collection with the i386 arch.

 (2) Discards __iounmap() as it's not used.

 (3) Fixes the use of the SWAP/SWAPI instruction to get the arguments the right
     way around in atomic.h, and also to get the asm constraints correct.

 (4) Moves copy_to/from_user_page() to asm/cacheflush.h to be consistent with
     other archs.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

CONFIG_TIME_LOW_RES is a temporary way for architectures to signal that
they simply return xtime in do_gettimeoffset().  In this corner-case we
want to round up by resolution when starting a relative timer, to avoid
short timeouts.  This will go away with the GTOD framework.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix __delay implementation.  Called with an argument "1" or "0" it would
loop nearly forever (since (1/2)-1 = 0xffffffff).
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Jean-Luc Leger <reiga@dspnet.fr.eu.org> found this obvious typo.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NThomas Koeller  <thomas.koeller@baslerweb.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

    
Add blast_xxx_range(), protected_blast_xxx_range() etc. for common
use.  They are built by __BUILD_BLAST_CACHE_RANGE().
Use protected_cache_op() macro for various protected_ routines.
Output code should be logically same.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

    
Implement get_wchan() and frame_info_init() using kallsyms_lookup().
This fixes problem with static sched/lock functions and mfinfo[]
maintenance issue.  If CONFIG_KALLSYMS was disabled, get_wchan() just
returns thread_saved_pc() value.
    
Also unwind stackframe based on "addiu sp,-imm" analysis instead of
frame pointer.  This fixes problem with functions compiled without
-fomit-frame-pointer.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Fix x86 oprofile regression introduced by:
  commit c34d1b4d
  [PATCH] mm: kill check_user_page_readable

That commit reorganized tests for the userspace stack walking moving all
those tests into dump_backtrace(), however, dump_backtrace() was used for
both userspace and kernel stalk walking.  The result is typically no
recorded callgraph information for kernel samples.

Revive the original function as dump_kernel_backtrace() and rename the
other to dump_user_backtrace() to avoid future confusion.
Signed-off-by: NGerald Britton <gbritton@alum.mit.edu>
Apology-from: Hugh Dickins <hugh@veritas.com>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

parisc defines ARCH_WANT_STAT64, so we want to use fstatat64. It does not
appear that it needs to be ENTRY_COMP, because struct stat64 is the same
on both 32-bit and 64-bit (unlike on other platforms which did define a
compat_sys_fstatat64.)
Signed-off-by: NGrant Grundler <grundler@parisc-linux.org>
Signed-off-by: NKyle McMartin <kyle@parisc-linux.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

As noted by Jan Dittmer <jdi@l4x.org>
Signed-off-by: NYoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Don't touch the non DMA members in the sg list in dma_map_sg in the IOMMU

Some drivers (in particular ST) ran into problems because they reused the sg
lists after passing them to pci_map_sg().  The merging procedure in the K8
GART IOMMU corrupted the state.  This patch changes it to only touch the dma*
entries during merging, but not the other fields.  Approach suggested by Dave
Miller.
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We found a problem with x86_64 kernels with preemption enabled, where
having multiple tasks doing ptrace singlesteps around the same time will
cause the system to 'oops'.  The problem seems that a task can get
preempted out of the do_debug() processing while it is running on the
DEBUG_STACK stack.  If another task on that same cpu then enters do_debug()
and uses the same per-cpu DEBUG_STACK stack, the previous preempted tasks's
stack contents can be corrupted, and the system will oops when the
preempted task is context switched back in again.

The typical oops looks like the following:

  Unable to handle kernel paging request at ffffffffffffffae RIP: <ffffffff805452a1>{thread_return+34}
  PGD 103027 PUD 102429067 PMD 0
  Oops: 0002 [1] PREEMPT SMP
  CPU 0
  Modules linked in:
  Pid: 3786, comm: ssdd Not tainted 2.6.15.2 #1
  RIP: 0010:[<ffffffff805452a1>] <ffffffff805452a1>{thread_return+34}
  RSP: 0018:ffffffff80824058  EFLAGS: 000136c2
  RAX: ffff81017e12cea0 RBX: 0000000000000000 RCX: 00000000c0000100
  RDX: 0000000000000000 RSI: ffff8100f7856e20 RDI: ffff81017e12cea0
  RBP: 0000000000000046 R08: ffff8100f68a6000 R09: 0000000000000000
  R10: 0000000000000000 R11: ffff81017e12cea0 R12: ffff81000c2d53e8
  R13: ffff81017f5b3be8 R14: ffff81000c0036e0 R15: 000001056cbfc899
  FS:  00002aaaaaad9b00(0000) GS:ffffffff80883800(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
  CR2: ffffffffffffffae CR3: 00000000f6fcf000 CR4: 00000000000006e0
  Process ssdd (pid: 3786, threadinfo ffff8100f68a6000, task ffff8100f7856e20)
  Stack: ffffffff808240d8 ffffffff8012a84a ffff8100055f6c00 0000000000000020
         0000000000000001 ffff81000c0036e0 ffffffff808240b8 0000000000000000
         0000000000000000 0000000000000000
  Call Trace: <#DB>
	<ffffffff8012a84a>{try_to_wake_up+985}
	<ffffffff8012c0d3>{kick_process+87}
        <ffffffff8013b262>{signal_wake_up+48}
	<ffffffff8013b5ce>{specific_send_sig_info+179}
        <ffffffff80546abc>{_spin_unlock_irqrestore+27}
	<ffffffff8013b67c>{force_sig_info+159}
        <ffffffff801103a0>{do_debug+289} <ffffffff80110278>{sync_regs+103}
        <ffffffff8010ed9a>{paranoid_userspace+35}
  Unable to handle kernel paging request at 00007fffffb7d000 RIP: <ffffffff8010f2e4>{show_trace+465}
  PGD f6f25067 PUD f6fcc067 PMD f6957067 PTE 0
  Oops: 0000 [2] PREEMPT SMP

This patch disables preemptions for the task upon entry to do_debug(), before
interrupts are reenabled, and then disables preemption before exiting
do_debug(), after disabling interrupts.  I've noticed that the task can be
preempted either at the end of an interrupt, or on the call to
force_sig_info() on the spin_unlock_irqrestore() processing.  It might be
better to attempt to code a fix in entry.S around the code that calls
do_debug().
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add fstatat64 support to s390 in order to follow changes with
commit cff2b760 .
Also fixes compilation for 31 bit.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add support for unshare system call.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add missing smp_cpu_not_running define to avoid build warnings in the non smp
case.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Initiliazing of cpu_possible_map was done in smp_prepare_cpus which is way too
late.  Therefore assign a static value to cpu_possible_map, since we don't
have access to max_cpus in setup_arch.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Switch on CONFIG_DEBUG_FS again.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Lost a few hours debugging an early-bootup fault within printk itself,
which manifested itself as a hard to debug early hang.

This patch makes it much easier by printing out early faults via
early_printk(), which function is a lot simpler than a full printk, and
hence more likely to succeed in emergencies.  (We do not recover from early
faults anyway, so there's no loss from not having these messages in the
normal printk buffer.)
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

[description from AK]

The IBM Summit 3 chipset doesn't implement the HPET timer replacement
option.  Since the current Linux code relies on it use a mixed mode with
both PIT for the interrupt and HPET counters for the time keeping.  That
was already implemented, but didn't work properly because it was still
using the last interrupt offset in HPET.  This resulted in x460 not
booting.  Fix this up by using the free running HPET counter.

Shouldn't affect any other machine because they either use full HPET mode
or no HPET at all.

TBD needs a similar 32bit fix.
Signed-off-by: NAndi Kleen <ak@suse.de>
Cc: Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com>
Cc: Bob Picco <bob.picco@hp.com>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Acked-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NMatt Waddel <Matt.Waddel@freescale.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The *at patches introduced fstatat and, due to inusfficient research, I
used the newfstat functions generally as the guideline.  The result is that
on 32-bit platforms we don't have all the information needed to implement
fstatat64.

This patch modifies the code to pass up 64-bit information if
__ARCH_WANT_STAT64 is defined.  I renamed the syscall entry point to make
this clear.  Other archs will continue to use the existing code.  On x86-64
the compat code is implemented using a new sys32_ function.  this is what
is done for the other stat syscalls as well.

This patch might break some other archs (those which define
__ARCH_WANT_STAT64 and which already wired up the syscall).  Yet others
might need changes to accomodate the compatibility mode.  I really don't
want to do that work because all this stat handling is a mess (more so in
glibc, but the kernel is also affected).  It should be done by the arch
maintainers.  I'll provide some stand-alone test shortly.  Those who are
eager could compile glibc and run 'make check' (no installation needed).

The patch below has been tested on x86 and x86-64.
Signed-off-by: NUlrich Drepper <drepper@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Patch from Ben Dooks

Define the bits for the two board control latches
that control various items on the H1940 iPAQ.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NArnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/s390/kernel/compat_signal.c:199: error: conflicting types for 'do_sigaction'
include/linux/sched.h:1115: error: previous declaration of 'do_sigaction' was here
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Initialising cpu_possible_map to all-ones with CONFIG_HOTPLUG_CPU means that

a) All for_each_cpu() loops will iterate across all NR_CPUS CPUs, rather
   than over possible ones.  That can be quite expensive.

b) Soon we'll be allocating per-cpu areas only for possible CPUs.  So with
   CPU_MASK_ALL, we'll be wasting memory.

I also switched voyager over to not use CPU_MASK_ALL in the non-CPU-hotplug
case.  Should be OK..

I note that parisc is also using CPU_MASK_ALL.  Suggest that it stop doing
that.

Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Paul Jackson <pj@sgi.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Zwane Mwaikambo <zwane@linuxpower.ca>
Cc: Paul Jackson <pj@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We are setting up sources for building external modules like this:

  /usr/src/linux-obj> # create a .config file
  /usr/src/linux-obj> make -C /usr/src/linux O=$PWD oldconfig
  /usr/src/linux-obj> make -C /usr/src/linux O=$PWD prepare
  /usr/src/linux-obj> make -C /usr/src/linux O=$PWD scripts
  /usr/src/linux-obj> make -C /usr/src/linux O=$PWD clean

After that, external modules can be built with:

  /usr/src/module> make -C /usr/src/linux-obj M=$PWD

This fails for ppc32 because the `make clean' removes the
arch/powerpc/include directory.  This should be done in archmrproper
instead of in archclean.
Signed-off-by: NAndreas Gruenbacher <agruen@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>