If we don't have any Moorestown CPU support compiled in, we don't need
the Moorestown PCI support either.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4B858E89.7040807@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The NUMAQ initialization sets x86_init.pci.init to pci_numaq_init,
which obviously isn't defined if CONFIG_PCI isn't defined.  This
dependency was implicit in the past, because pci_numaq_init was
invoked from arch/x86/pci/legacy.c, which itself was conditioned on
CONFIG_PCI.

I suspect that no NUMA-Q machines without PCI were ever built, so
instead of complicating the code by adding #ifdefs or stub functions,
just disable this bit of the configuration space.

[ hpa: rewrote the checkin comment ]
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F0755A321EE1F@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

While probing for the PCI fixed BAR capability in the extended PCI
configuration space we need to make sure raw_pci_ext_ops is
actually initialized.
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F0755A321E8F7@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Remove duplicated cfg[i].vector assignment.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4B8493A0.6080501@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

nr_legacy_irqs and its ilk have moved to legacy_pic.

-v2: there is one in ioapic_.c
Singed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4B84AAC4.2020204@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Add Moorestown platform clock setup code to the x86_init abstraction.
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F0755A318D2D4@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Moorestown platform does not have PIT or HPET platform timers.  Instead it
has a bank of eight APB timers.  The number of available timers to the os
is exposed via SFI mtmr tables.  All APB timer interrupts are routed via
ioapic rtes and delivered as MSI.
Currently, we use timer 0 and 1 for per cpu clockevent devices, timer 2
for clocksource.
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F0755A318D2D2@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

vRTC information is obtained from SFI tables on Moorestown, this patch parses
these tables and assign the information.
Signed-off-by: NFeng Tang <feng.tang@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D0D@orsmsx508.amr.corp.intel.com>
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Moorestown platform timer information is obtained from SFI FW tables.
This patch parses SFI table then assign the irq information to mp_irqs.
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D0B@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

This patch added Moorestown platform specific PCI init functions.
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D0A@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Moorestown has no legacy PIC; point it to the null legacy PIC.
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D09@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The Moorestown platform only has a few devices that actually support
PCI config cycles.  The rest of the devices use an in-RAM MCFG space
for the purposes of device enumeration and initialization.

There are a few uglies in the fake support, like BAR sizes that aren't
a power of two, sizing detection, and writes to the real devices, but
other than that it's pretty straightforward.

Another way to think of this is not really as PCI at all, but just a
table in RAM describing which devices are present, their capabilities
and their offsets in MMIO space.  This could have been done with a
special new firmware table on this platform, but given that we do have
some real PCI devices too, simply describing things in an MCFG type
space was pretty simple.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D08@orsmsx508.amr.corp.intel.com>
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Some ioapic extern functions are used when CONFIG_X86_IO_APIC is not
defined.  We need the dummy functions to avoid a compile time error.
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F0755A318DA07@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Moorestown platform needs apic ready early for the system timer irq
which is delievered via ioapic.  Should not impact other platforms.

In the longer term, once ioapic setup is moved before late time init,
we will not need this patch to do early apic enabling.
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D07@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Move legacy_pic chip dummy functions out of init section as they might
be referenced at run time.
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F0755A318D3AA@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The ioapic_disable_legacy() call is no longer needed for platforms do
not have legacy pic. the legacy pic abstraction has taken care it
automatically.

This patch also initialize irq-related static variables based on
information obtained from legacy_pic.
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F0755A30A7660@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

This patch replaces legacy PIC-related global variable and functions
with the new legacy_pic abstraction.
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D04@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

This patch makes i8259A like legacy programmable interrupt controller
code into a driver so that legacy pic functions can be selected at
runtime based on platform information, such as HW subarchitecure ID.
Default structure of legacy_pic maintains the current code path for
x86pc.
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D03@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Some secondary clockevent setup code needs to call request_irq, which
will cause fake stack check failure in schedule() if voluntary
preemption model is chosen.  It is safe to have stack canary
initialized here early, since start_secondary() does not return.
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D02@orsmsx508.amr.corp.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Since we already track the number of legacy vectors by nr_legacy_irqs, we
can avoid use static vector allocations -- we can use dynamic one.
Signed-off-by: NAlek Du <alek.du@intel.com>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D01@orsmsx508.amr.corp.intel.com>
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Platforms like Moorestown want to override the pcibios_fixup_irqs
default function. Add it to x86_init.pci.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D00@orsmsx508.amr.corp.intel.com>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Moorestown wants to reuse pcibios_init_irq but needs to provide its
own implementation of pci_enable_irq. After we distangled the init we
can move the init_irq call to x86_init and remove the pci_enable_irq
!= NULL check in pcibios_init_irq. pci_enable_irq is compile time
initialized to pirq_enable_irq and the special cases which override it
(visws and acpi) set the x86_init function pointer to noop. That
allows MSRT to override pci_enable_irq and otherwise run
pcibios_init_irq unmodified.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80CFF@orsmsx508.amr.corp.intel.com>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The PCI initialization in pci_subsys_init() is a mess. pci_numaq_init,
pci_acpi_init, pci_visws_init and pci_legacy_init are called and each
implementation checks and eventually modifies the global variable
pcibios_scanned.

x86_init functions allow us to do this more elegant. The pci.init
function pointer is preset to pci_legacy_init. numaq, acpi and visws
can modify the pointer in their early setup functions. The functions
return 0 when they did the full initialization including bus scan. A
non zero return value indicates that pci_legacy_init needs to be
called either because the selected function failed or wants the
generic bus scan in pci_legacy_init to happen (e.g. visws).
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80CFE@orsmsx508.amr.corp.intel.com>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Version 4: use get_irq_chip_data() in destroy_irq() to get rid of some
local vars.

When two drivers are setting up MSI-X at the same time via
pci_enable_msix() there is a race.  See this dmesg excerpt:

[   85.170610] ixgbe 0000:02:00.1: irq 97 for MSI/MSI-X
[   85.170611]   alloc irq_desc for 99 on node -1
[   85.170613] igb 0000:08:00.1: irq 98 for MSI/MSI-X
[   85.170614]   alloc kstat_irqs on node -1
[   85.170616] alloc irq_2_iommu on node -1
[   85.170617]   alloc irq_desc for 100 on node -1
[   85.170619]   alloc kstat_irqs on node -1
[   85.170621] alloc irq_2_iommu on node -1
[   85.170625] ixgbe 0000:02:00.1: irq 99 for MSI/MSI-X
[   85.170626]   alloc irq_desc for 101 on node -1
[   85.170628] igb 0000:08:00.1: irq 100 for MSI/MSI-X
[   85.170630]   alloc kstat_irqs on node -1
[   85.170631] alloc irq_2_iommu on node -1
[   85.170635]   alloc irq_desc for 102 on node -1
[   85.170636]   alloc kstat_irqs on node -1
[   85.170639] alloc irq_2_iommu on node -1
[   85.170646] BUG: unable to handle kernel NULL pointer dereference
at 0000000000000088

As you can see igb and ixgbe are both alternating on create_irq_nr()
via pci_enable_msix() in their probe function.

ixgbe: While looping through irq_desc_ptrs[] via create_irq_nr() ixgbe
choses irq_desc_ptrs[102] and exits the loop, drops vector_lock and
calls dynamic_irq_init. Then it sets irq_desc_ptrs[102]->chip_data =
NULL via dynamic_irq_init().

igb: Grabs the vector_lock now and starts looping over irq_desc_ptrs[]
via create_irq_nr(). It gets to irq_desc_ptrs[102] and does this:

	cfg_new = irq_desc_ptrs[102]->chip_data;
	if (cfg_new->vector != 0)
		continue;

This hits the NULL deref.

Another possible race exists via pci_disable_msix() in a driver or in
the number of error paths that call free_msi_irqs():

destroy_irq()
dynamic_irq_cleanup() which sets desc->chip_data = NULL
...race window...
desc->chip_data = cfg;

Remove the save and restore code for cfg in create_irq_nr() and
destroy_irq() and take the desc->lock when checking the irq_cfg.
Reported-and-analyzed-by: NBrandon Philips <bphilips@suse.de>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <20100207210250.GB8256@jenkins.home.ifup.org>
Signed-off-by: NBrandon Phiilps <bphilips@suse.de>
Cc: stable@kernel.org
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

On x86, before prefill_possible_map(), nr_cpu_ids will be NR_CPUS aka
CONFIG_NR_CPUS.

Add nr_cpus= to set nr_cpu_ids. so we can simulate cpus <=8 are installed on
normal config.

-v2: accordging to Christoph, acpi_numa_init should use nr_cpu_ids in stead of
     NR_CPUS.
-v3: add doc in kernel-parameters.txt according to Andrew.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-34-git-send-email-yinghai@kernel.org>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: Tony Luck <tony.luck@intel.com>

So keep nr_irqs == NR_IRQS.  With radix trees is matters less.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-33-git-send-email-yinghai@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

On the iMac9,1 /sbin/reboot results in a black mangled screen. Adding
this DMI entry gets the machine to reboot cleanly as it should.
Signed-off-by: NJustin P. Mattock <justinmattock@gmail.com>
LKML-Reference: <1266362249-3337-1-git-send-email-justinmattock@gmail.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

nmi_lock must be a spinning spinlock in -rt.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Keep chip_data in create_irq_nr and destroy_irq.

When two drivers are setting up MSI-X at the same time via
pci_enable_msix() there is a race.  See this dmesg excerpt:

[   85.170610] ixgbe 0000:02:00.1: irq 97 for MSI/MSI-X
[   85.170611]   alloc irq_desc for 99 on node -1
[   85.170613] igb 0000:08:00.1: irq 98 for MSI/MSI-X
[   85.170614]   alloc kstat_irqs on node -1
[   85.170616] alloc irq_2_iommu on node -1
[   85.170617]   alloc irq_desc for 100 on node -1
[   85.170619]   alloc kstat_irqs on node -1
[   85.170621] alloc irq_2_iommu on node -1
[   85.170625] ixgbe 0000:02:00.1: irq 99 for MSI/MSI-X
[   85.170626]   alloc irq_desc for 101 on node -1
[   85.170628] igb 0000:08:00.1: irq 100 for MSI/MSI-X
[   85.170630]   alloc kstat_irqs on node -1
[   85.170631] alloc irq_2_iommu on node -1
[   85.170635]   alloc irq_desc for 102 on node -1
[   85.170636]   alloc kstat_irqs on node -1
[   85.170639] alloc irq_2_iommu on node -1
[   85.170646] BUG: unable to handle kernel NULL pointer dereference
at 0000000000000088

As you can see igb and ixgbe are both alternating on create_irq_nr()
via pci_enable_msix() in their probe function.

ixgbe: While looping through irq_desc_ptrs[] via create_irq_nr() ixgbe
choses irq_desc_ptrs[102] and exits the loop, drops vector_lock and
calls dynamic_irq_init. Then it sets irq_desc_ptrs[102]->chip_data =
NULL via dynamic_irq_init().

igb: Grabs the vector_lock now and starts looping over irq_desc_ptrs[]
via create_irq_nr(). It gets to irq_desc_ptrs[102] and does this:

	cfg_new = irq_desc_ptrs[102]->chip_data;
	if (cfg_new->vector != 0)
		continue;

This hits the NULL deref.

Another possible race exists via pci_disable_msix() in a driver or in
the number of error paths that call free_msi_irqs():

destroy_irq()
dynamic_irq_cleanup() which sets desc->chip_data = NULL
...race window...
desc->chip_data = cfg;

Remove the save and restore code for cfg in create_irq_nr() and
destroy_irq() and take the desc->lock when checking the irq_cfg.
Reported-and-analyzed-by: NBrandon Philips <bphilips@suse.de>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-3-git-send-email-yinghai@kernel.org>
Signed-off-by: NBrandon Phililps <bphilips@suse.de>
Cc: stable@kernel.org
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Thomas Renninger <trenn@suse.de> reported on IBM x3330

booting a latest kernel on this machine results in:

PCI: PCI BIOS revision 2.10 entry at 0xfd61c, last bus=1
PCI: Using configuration type 1 for base access bio: create slab <bio-0> at 0
ACPI: SCI (IRQ30) allocation failed
ACPI Exception: AE_NOT_ACQUIRED, Unable to install System Control Interrupt handler (20090903/evevent-161)
ACPI: Unable to start the ACPI Interpreter

Later all kind of devices fail...

and bisect it down to this commit:
commit b9c61b70

    x86/pci: update pirq_enable_irq() to setup io apic routing

it turns out we need to set irq routing for the sci on ioapic1 early.

-v2: make it work without sparseirq too.
-v3: fix checkpatch.pl warning, and cc to stable
Reported-by: NThomas Renninger <trenn@suse.de>
Bisected-by: NThomas Renninger <trenn@suse.de>
Tested-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-2-git-send-email-yinghai@kernel.org>
Cc: stable@kernel.org
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Do not set current->mm->mmap to NULL in 32-bit emulation on 64-bit
load_aout_binary after flush_old_exec as it would destroy already
set brpm mapping with arguments.

Introduced by b6a2fea3
mm: variable length argument support
where the argument mapping in bprm was added.

[ hpa: this is a regression from 2.6.22... time to kill a.out? ]
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
LKML-Reference: <1265831716-7668-1-git-send-email-jslaby@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ollie Wild <aaw@google.com>
Cc: x86@kernel.org
Cc: <stable@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

We need to fall back from logical-flat APIC mode to physical-flat mode
when we have more than 8 CPUs.  However, in the presence of CPU
hotplug(with bios listing not enabled but possible cpus as disabled cpus in
MADT), we have to consider the number of possible CPUs rather than
the number of current CPUs; otherwise we may cross the 8-CPU boundary
when CPUs are added later.

32bit apic code can use more cleanups (like the removal of vendor checks in
32bit default_setup_apic_routing()) and more unifications with 64bit code.
Yinghai has some patches in works already. This patch addresses the boot issue
that is reported in the virtualization guest context.

[ hpa: incorporated function annotation feedback from Yinghai Lu ]
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1265767304.2833.19.camel@sbs-t61.sc.intel.com>
Acked-by: NShaohui Zheng <shaohui.zheng@intel.com>
Reviewed-by: NYinghai Lu <yinghai@kernel.org>
Cc: <stable@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Both x86-32 and x86-64 with 32-bit compat use ARCH_DLINFO_IA32,
which defines two saved_auxv entries.  But system.h only defines
AT_VECTOR_SIZE_ARCH as 2 for CONFIG_IA32_EMULATION, not for
CONFIG_X86_32.  Fix that.
Signed-off-by: NSerge E. Hallyn <serue@us.ibm.com>
LKML-Reference: <20100209023502.GA15408@us.ibm.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

PIT control word (address 0x43) is write-only, reads are undefined.

Cc: stable@kernel.org
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Current kvm wallclock does not consider the total_sleep_time which could cause
wrong wallclock in guest after host suspend/resume. This patch solve
this issue by counting total_sleep_time to get the correct host boot time.

Cc: stable@kernel.org
Signed-off-by: NJason Wang <jasowang@redhat.com>
Acked-by: NGlauber Costa <glommer@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Newly added memory can not be accessed via /dev/mem, because we do not
update the variables high_memory, max_pfn and max_low_pfn.

Add a function update_end_of_memory_vars() to update these variables for
64-bit kernels.

[akpm@linux-foundation.org: simplify comment]
Signed-off-by: NShaohui Zheng <shaohui.zheng@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Li Haicheng <haicheng.li@intel.com>
Reviewed-by: NWu Fengguang <fengguang.wu@intel.com>
Reviewed-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix minor spelling error in comment.  No code change.
Signed-off-by: NAndy Shevchenko <ext-andriy.shevchenko@nokia.com>
LKML-Reference: <201002022238.o12McDiF018720@imap1.linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

This patch fixes the regression in functionality where the
kernel debugger and the perf API do not nicely share hw
breakpoint reservations.

The kernel debugger cannot use any mutex_lock() calls because it
can start the kernel running from an invalid context.

A mutex free version of the reservation API needed to get
created for the kernel debugger to safely update hw breakpoint
reservations.

The possibility for a breakpoint reservation to be concurrently
processed at the time that kgdb interrupts the system is
improbable. Should this corner case occur the end user is
warned, and the kernel debugger will prohibit updating the
hardware breakpoint reservations.

Any time the kernel debugger reserves a hardware breakpoint it
will be a system wide reservation.
Signed-off-by: NJason Wessel <jason.wessel@windriver.com>
Acked-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: kgdb-bugreport@lists.sourceforge.net
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: torvalds@linux-foundation.org
LKML-Reference: <1264719883-7285-3-git-send-email-jason.wessel@windriver.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>