When using kdump modifying the e820 map is yielding strange results.

For example starting with

 BIOS-provided physical RAM map:
 BIOS-e820: 0000000000000100 - 0000000000093400 (usable)
 BIOS-e820: 0000000000093400 - 00000000000a0000 (reserved)
 BIOS-e820: 0000000000100000 - 000000003fee0000 (usable)
 BIOS-e820: 000000003fee0000 - 000000003fef3000 (ACPI data)
 BIOS-e820: 000000003fef3000 - 000000003ff80000 (ACPI NVS)
 BIOS-e820: 000000003ff80000 - 0000000040000000 (reserved)
 BIOS-e820: 00000000e0000000 - 00000000f0000000 (reserved)
 BIOS-e820: 00000000fec00000 - 00000000fec10000 (reserved)
 BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved)
 BIOS-e820: 00000000ff000000 - 0000000100000000 (reserved)

and booting with args

memmap=exactmap memmap=640K@0K memmap=5228K@16384K memmap=125188K@22252K memmap=76K#1047424K memmap=564K#1047500K

resulted in:

 user-defined physical RAM map:
 user: 0000000000000000 - 0000000000093400 (usable)
 user: 0000000000093400 - 00000000000a0000 (reserved)
 user: 0000000000100000 - 000000003fee0000 (usable)
 user: 000000003fee0000 - 000000003fef3000 (ACPI data)
 user: 000000003fef3000 - 000000003ff80000 (ACPI NVS)
 user: 000000003ff80000 - 0000000040000000 (reserved)
 user: 00000000e0000000 - 00000000f0000000 (reserved)
 user: 00000000fec00000 - 00000000fec10000 (reserved)
 user: 00000000fee00000 - 00000000fee01000 (reserved)
 user: 00000000ff000000 - 0000000100000000 (reserved)

But should have resulted in:

 user-defined physical RAM map:
 user: 0000000000000000 - 00000000000a0000 (usable)
 user: 0000000001000000 - 000000000151b000 (usable)
 user: 00000000015bb000 - 0000000008ffc000 (usable)
 user: 000000003fee0000 - 000000003ff80000 (ACPI data)

This is happening because of an improper usage of strcmp() in the
e820 parsing code.  The strcmp() always returns !0 and never resets the
value for e820.nr_map and returns an incorrect user-defined map.

This patch fixes the problem.
Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

It was introduced by "vsprintf: add support for '%pS' and '%pF' pointer
formats" in commit 0fe1ef24.  However,
the current way its coded doesn't work on parisc64.  For two reasons: 1)
parisc isn't in the #ifdef and 2) parisc has a different format for
function descriptors

Make dereference_function_descriptor() more accommodating by allowing
architecture overrides.  I put the three overrides (for parisc64, ppc64
and ia64) in arch/kernel/module.c because that's where the kernel
internal linker which knows how to deal with function descriptors sits.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NTony Luck <tony.luck@intel.com>
Acked-by: NKyle McMartin <kyle@mcmartin.ca>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When running a 31-bit ptrace, on either an s390 or s390x kernel,
reads and writes into a padding area in struct user_regs_struct32
will result in a kernel panic.

This is also known as CVE-2008-1514.

Test case available here:
http://sources.redhat.com/cgi-bin/cvsweb.cgi/~checkout~/tests/ptrace-tests/tests/user-area-padding.c?cvsroot=systemtap

Steps to reproduce:
1) wget the above
2) gcc -o user-area-padding-31bit user-area-padding.c -Wall -ggdb2 -D_GNU_SOURCE -m31
3) ./user-area-padding-31bit
<panic>

Test status
-----------
Without patch, both s390 and s390x kernels panic. With patch, the test case,
as well as the gdb testsuite, pass without incident, padding area reads
returning zero, writes ignored.

Nb: original version returned -EINVAL on write attempts, which broke the
gdb test and made the test case slightly unhappy, Jan Kratochvil suggested
the change to return 0 on write attempts.
Signed-off-by: NJarod Wilson <jarod@redhat.com>
Tested-by: NJan Kratochvil <jan.kratochvil@redhat.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

When a CPU is offlined, we leave the timer interrupts disabled
because fixup_irqs() does not explicitly take care of that case.

Fix this by invoking tick_ops->disable_irq().

Based upon analysis done by Paul E. McKenney.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On 32-bit, at least the generic nops are fairly reasonable, but the
default nops for 64-bit really look pretty sad, and the P6 nops really do
look better.

So I would suggest perhaps moving the static P6 nop selection into the
CONFIG_X86_64 thing.

The alternative is to just get rid of that static nop selection, and just
have two cases: 32-bit and 64-bit, and just pick obviously safe cases for
them.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The second HPC3 could be found only on Guiness systems (Challenge-S),
but not on fullhouse (Indigo2) systems.
Signed-off-by: NThomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

A make -j20 powerpc kernel build broke a couple of months ago saying:
In file included from arch/powerpc/boot/gunzip_util.h:13,
                 from arch/powerpc/boot/prpmc2800.c:21:
arch/powerpc/boot/zlib.h:85: error: expected ‘:’, ‘,’, ‘;’, ‘}’ or ‘__attribute__’ before ‘*’ token
arch/powerpc/boot/zlib.h:630: warning: type defaults to ‘int’ in declaration of ‘Byte’
arch/powerpc/boot/zlib.h:630: error: expected ‘;’, ‘,’ or ‘)’ before ‘*’ token

It happened again yesterday: too rare for me to confirm the fix, but
it looks like the list of dependants on gunzip_util.h was incomplete.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

We currently have a race when scheduling a context to a SPE -
after we have found a runnable context in spusched_tick, the same
context may have been scheduled by spu_activate().

This may result in a panic if we try to unschedule a context that has
been freed in the meantime.

This change exits spu_schedule() if the context has already been
scheduled, so we don't end up scheduling it twice.
Signed-off-by: NAndre Detsch <adetsch@br.ibm.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>

Exception stacks are allocated each time a CPU is set online.
But the allocated space is never freed. Thus with one CPU hotplug
offline/online cycle there is a memory leak of 24K (6 pages) for
a CPU.

Fix is to allocate exception stacks only once -- when the CPU is
set online for the first time.
Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
Cc: akpm@linux-foundation.org
Signed-off-by: NIngo Molnar <mingo@elte.hu>

pda->irqstackptr is allocated whenever a CPU is set online.
But it is never freed. This results in a memory leak of 16K
for each CPU offline/online cycle.

Fix is to allocate pda->irqstackptr only once.
Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
Cc: akpm@linux-foundation.org
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Using native_pte_val triggers the BUG_ON() in the paravirt_ops
version of pte_flags().
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Acked-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Krzysztof Helt found MTRR is not detected on k6-2

root cause:
	we moved mtrr_bp_init() early for mtrr trimming,
and in early_detect we only read the CPU capability from cpuid,
so some cpu doesn't have that bit in cpuid.

So we need to add early_init_xxxx to preset those bit before mtrr_bp_init
for those earlier cpus.

this patch is for v2.6.27
Reported-by: NKrzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Move early cpu initialization after cpu early get cap so the
early cpu initialization can fix up cpu caps.
Signed-off-by: NKrzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch provides an ARM implementation of ioremap_wc().

We use different page table attributes depending on which CPU we
are running on:

- Non-XScale ARMv5 and earlier systems: The ARMv5 ARM documents four
  possible mapping types (CB=00/01/10/11).  We can't use any of the
  cached memory types (CB=10/11), since that breaks coherency with
  peripheral devices.  Both CB=00 and CB=01 are suitable for _wc, and
  CB=01 (Uncached/Buffered) allows the hardware more freedom than
  CB=00, so we'll use that.

  (The ARMv5 ARM seems to suggest that CB=01 is allowed to delay stores
  but isn't allowed to merge them, but there is no other mapping type
  we can use that allows the hardware to delay and merge stores, so
  we'll go with CB=01.)

- XScale v1/v2 (ARMv5): same as the ARMv5 case above, with the slight
  difference that on these platforms, CB=01 actually _does_ allow
  merging stores.  (If you want noncoalescing bufferable behavior
  on Xscale v1/v2, you need to use XCB=101.)

- Xscale v3 (ARMv5) and ARMv6+: on these systems, we use TEXCB=00100
  mappings (Inner/Outer Uncacheable in xsc3 parlance, Uncached Normal
  in ARMv6 parlance).

  The ARMv6 ARM explicitly says that any accesses to Normal memory can
  be merged, which makes Normal memory more suitable for _wc mappings
  than Device or Strongly Ordered memory, as the latter two mapping
  types are guaranteed to maintain transaction number, size and order.
  We use the Uncached variety of Normal mappings for the same reason
  that we can't use C=1 mappings on ARMv5.

  The xsc3 Architecture Specification documents TEXCB=00100 as being
  Uncacheable and allowing coalescing of writes, which is also just
  what we need.
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

After fixing the u32 thinko I sill had occasional hickups on ATI chipsets
with small deltas. There seems to be a delay between writing the compare
register and the transffer to the internal register which triggers the
interrupt. Reading back the value makes sure, that it hit the internal
match register befor we compare against the counter value.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

We use the HPET only in 32bit mode because:
1) some HPETs are 32bit only
2) on i386 there is no way to read/write the HPET atomic 64bit wide

The HPET code unification done by the "moron of the year" did
not take into account that unsigned long is different on 32 and
64 bit.

This thinko results in a possible endless loop in the clockevents
code, when the return comparison fails due to the 64bit/332bit
unawareness. 

unsigned long cnt = (u32) hpet_read() + delta can wrap over 32bit.
but the final compare will fail and return -ETIME causing endless
loops.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Use X86_FEATURE_NOPL to determine if it is safe to use P6 NOPs in
alternatives.  Also, replace table and loop with simple if statement.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The long noops ("NOPL") are supposed to be detected by family >= 6.
Unfortunately, several non-Intel x86 implementations, both hardware
and software, don't obey this dictum.  Instead, probe for NOPL
directly by executing a NOPL instruction and see if we get #UD.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The CPU feature detection code in the boot code is somewhat minimal,
and doesn't include all possible CPUID words.  In particular, it
doesn't contain the code for CPU feature words 2 (Transmeta),
3 (Linux-specific), 5 (VIA), or 7 (scattered).  Zero them out, so we
can still set those bits as known at compile time; in particular, this
allows creating a Linux-specific NOPL flag and have it required (and
therefore resolvable at compile time) in 64-bit mode.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Currently init_initrd() probes initrd header at the last page of kernel
image, but it is valid only if addinitrd was used.  If addinitrd was not
used, the area contains garbage so probing there might misdetect initrd
header (magic number is not strictly robust).

This patch introduces CONFIG_PROBE_INITRD_HEADER to explicitly enable this
probing.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Commmit 59e39ecd933ba49eb6efe84cbfa5597a6c9ef18a ("Fix WARNING: at
kernel/smp.c:290") introduced local_flush_icache_range but lacks
initialization for some TX39 case.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The txx9_pcode variable was introduced in commit
fe1c2bc64f65003b39f331a8e4b0d15b235a4afd ("TXx9: Add 64-bit support")
but was not initialized properly.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

trap_init issues flush_icache_range(), which uses ipi functions to
get icache flushing done on all cpus. But this is done before interrupts
are enabled and caused WARN_ON messages. This changeset introduces
a new local_flush_icache_range() and uses it before interrupts (and
additional CPUs) are enabled to avoid this problem.
Signed-off-by: NThomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

With -ffunction-section the entries in __dbe_table aren't no longer
sorted, so the lookup of exception addresses in do_be() failed for
some addresses. To avoid this we now sort __dbe_table.
Signed-off-by: NThomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This reverts commit ae82cbfc. It
needs the new byteorder headers to be exported to userspace, and
they aren't yet -- and probably shouldn't be, at this point in the
2.6.27 release cycle (or ever, for that matter).
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The minimum reprogramming delta was hardcoded in HPET ticks,
which is stupid as it does not work with faster running HPETs.
The C1E idle patches made this prominent on AMD/RS690 chipsets,
where the HPET runs with 25MHz. Set it to 5us which seems to be
a reasonable value and fixes the problems on the bug reporters
machines. We have a further sanity check now in the clock events,
which increases the delta when it is not sufficient.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NLuiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Tested-by: NDmitry Nezhevenko <dion@inhex.net>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Follows the SH change.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This patch fixes a problem within the SH implementation of resume_kernel code,
that implements in assembly the bulk of preempt_schedule_irq function without
taking care of the extra code needed to handle the BKL preemptible.

The patch basically consists of removing this asm code and calling the common
C implementation (see kernel/sched.c) as other archs do.

Another change is the missing 'cli' macro invocation at the beginning of
the resume_kernel.
Signed-off-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NCarmelo Amoroso <carmelo.amoroso@st.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

We currently have a race for a free SPE. With one thread doing a
spu_yield(), and another doing a spu_activate():

thread 1				thread 2
spu_yield(oldctx)			spu_activate(ctx)
  __spu_deactivate(oldctx)
  spu_unschedule(oldctx, spu)
  spu->alloc_state = SPU_FREE
					spu = spu_get_idle(ctx)
					    - searches for a SPE in
					      state SPU_FREE, gets
					      the context just
					      freed by thread 1
					spu_schedule(ctx, spu)
					  spu->alloc_state = SPU_USED
spu_schedule(newctx, spu)
  - assumes spu is still free
  - tries to schedule context on
    already-used spu

This change introduces a 'free_spu' flag to spu_unschedule, to indicate
whether or not the function should free the spu after descheduling the
context. We only set this flag if we're not going to re-schedule
another context on this SPU.

Add a comment to document this behaviour.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>

Commit 8d5636fb introduced a reference
count on SPU contexts during find_victim, but this may cause a leak in
the reference count if we later find a better contender for a context to
unschedule.

Change the reference to after we've found our victim context, so we
don't do the extra get_spu_context().
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>

mcbsp is confused as to what takes a physical or virtual address.
Fix the two instances where it gets it wrong.
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The driver(s) below do not use LINUX_VERSION_CODE nor KERNEL_VERSION.
  arch/arm/plat-mxc/clock.c

This patch removes the said #include <version.h>.
Signed-off-by: NHuang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

When calibration against PIT fails, the warning that we print is misleading.
In a virtualized environment the VM may get descheduled while calibration
or, the check in PIT calibration may fail due to other virtualization
overheads.

The warning message explicitly assumes that calibration failed due to SMI's
which may not be the case. Change that to something proper.
Signed-off-by: NAlok N Kataria <akataria@vmware.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Manually adding "io_delay=0xed" fixes system lockups in ioapic
mode on this machine.

System Information
	Manufacturer: Hewlett-Packard
	Product Name: Presario F700 (KA695EA#ABF)

Base Board Information
	Manufacturer: Quanta
	Product Name: 30D3

Reference:
https://bugzilla.redhat.com/show_bug.cgi?id=459546Signed-off-by: NChuck Ebbert <cebbert@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The TSC calibration function is still very complicated, but this makes
it at least a little bit less so by moving the PIT part out into a
helper function of its own.
Tested-by: NLarry Finger <Larry.Finger@lwfinger.net>
Signed-of-by: NLinus Torvalds <torvalds@linux-foundation.org>

The calculation to get TI_CPU based off of SPRG3 was just plain wrong,
meaning that we were getting garbage for the CPU number on 6xx/G3/G4
based SMP boxes in this code.

Just offset off the stack pointer (to get to thread_info) like all the
other references to TI_CPU do.

This was pointed out by Chen Gong <G.Chen@freescale.com>

[paulus@samba.org - use rlwinm r12,r11,... instead of
 rlwinm r12,r1,...; tophys()]
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

HAVE_ARCH_UNMAPPED_AREA and HAVE_ARCH_UNMAPPED_AREA_TOPDOWN must
be defined whenever CONFIG_PPC_MM_SLICES is enabled, not just when
CONFIG_HUGETLB_PAGE is.  They used to be always defined together but
this is no longer the case since 3a8247cc
("powerpc: Only demote individual slices rather than whole process").
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This bug is causing random crashes
(http://bugzilla.kernel.org/show_bug.cgi?id=11414).

-fno-omit-frame-pointer is only needed on powerpc when -pg is also
supplied, and there is a gcc bug that causes incorrect code generation
on 32-bit powerpc when -fno-omit-frame-pointer is used---it uses stack
locations below the stack pointer, which is not allowed by the ABI
because those locations can and sometimes do get corrupted by an
interrupt.

This ensures that CONFIG_FRAME_POINTER is only selected by ftrace.
When CONFIG_FTRACE is enabled we also pass -mno-sched-epilog to work
around the gcc codegen bug.

Patch based on work by:
	Andreas Schwab <schwab@suse.de>
	Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: NTony Breeds <tony@bakeyournoodle.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This makes core_kernel_text() (and therefore kernel_text_address())
return the correct result.  Currently all the __devinit routines (at
least) will not be considered to be kernel text.

This is just a quick fix for 2.6.27 - hopefully we will be able to fix
this better in 2.6.28.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Commit bc033b63 ("powerpc/mm: Fix
attribute confusion with htab_bolt_mapping()") moved the check for
whether we should make pages of the linear mapping executable from
htab_bolt_mapping into its callers, including htab_initialize.
A side-effect of this is that the decision is now made once for
each contiguous section in the LMB array rather than for each page
individually.  This can often mean that the whole of the linear
mapping ends up being executable.

This reverts to the previous behaviour, where individual pages are
checked for being part of the kernel text or not, by moving the check
back down into htab_bolt_mapping.
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>