This is part of the ops structure constification
effort started by Arjan van de Ven et al.

Benefits of this constification:

 * prevents modification of data that is shared
   (referenced) by many other structure instances
   at runtime

 * detects/prevents accidental (but not intentional)
   modification attempts on archs that enforce
   read-only kernel data at runtime

 * potentially better optimized code as the compiler
   can assume that the const data cannot be changed

 * the compiler/linker move const data into .rodata
   and therefore exclude them from false sharing
Signed-off-by: NEmese Revfy <re.emese@gmail.com>
LKML-Reference: <4B65D712.3080804@gmail.com>
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>

In the 2.6.33 kernel, the hw_breakpoint API is now used for the
performance event counters.  The hw_breakpoint_handler() now
consumes the hw breakpoints that were previously set by kgdb
arch specific code.  In order for kgdb to work in conjunction
with this core API change, kgdb must use some of the low level
functions of the hw_breakpoint API to install, uninstall, and
deal with hw breakpoint reservations.

The kgdb core required a change to call kgdb_disable_hw_debug
anytime a slave cpu enters kgdb_wait() in order to keep all the
hw breakpoints in sync as well as to prevent hitting a hw
breakpoint while kgdb is active.

During the architecture specific initialization of kgdb, it will
pre-allocate 4 disabled (struct perf event **) structures.  Kgdb
will use these to manage the capabilities for the 4 hw
breakpoint registers, per cpu.  Right now the hw_breakpoint API
does not have a way to ask how many breakpoints are available,
on each CPU so it is possible that the install of a breakpoint
might fail when kgdb restores the system to the run state.  The
intent of this patch is to first get the basic functionality of
hw breakpoints working and leave it to the person debugging the
kernel to understand what hw breakpoints are in use and what
restrictions have been imposed as a result.  Breakpoint
constraints will be dealt with in a future patch.

While atomic, the x86 specific kgdb code will call
arch_uninstall_hw_breakpoint() and arch_install_hw_breakpoint()
to manage the cpu specific hw breakpoints.

The net result of these changes allow kgdb to use the same pool
of hw_breakpoints that are used by the perf event API, but
neither knows about future reservations for the available hw
breakpoint slots.
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: <1264719883-7285-2-git-send-email-jason.wessel@windriver.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Commit 6aa542a6 added a quirk for the
Intel DG45ID board due to low memory corruption. The Intel DG45FC
shares the same BIOS (and the same bug) as noted in:

  http://bugzilla.kernel.org/show_bug.cgi?id=13736Signed-off-by: NDavid Härdeman <david@hardeman.nu>
LKML-Reference: <20100128200254.GA9134@hardeman.nu>
Cc: <stable@kernel.org>
Cc: Alexey Fisher <bug-track@fisher-privat.net>
Cc: ykzhao <yakui.zhao@intel.com>
Cc: Tony Bones <aabonesml@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Now that the previous commit made it possible to do the personality
setting at the point of no return, we do just that for ELF binaries.
And suddenly all the reasons for that insane TIF_ABI_PENDING bit go
away, and we can just make SET_PERSONALITY() just do the obvious thing
for a 32-bit compat process.

Everything becomes much more straightforward this way.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

'flush_old_exec()' is the point of no return when doing an execve(), and
it is pretty badly misnamed.  It doesn't just flush the old executable
environment, it also starts up the new one.

Which is very inconvenient for things like setting up the new
personality, because we want the new personality to affect the starting
of the new environment, but at the same time we do _not_ want the new
personality to take effect if flushing the old one fails.

As a result, the x86-64 '32-bit' personality is actually done using this
insane "I'm going to change the ABI, but I haven't done it yet" bit
(TIF_ABI_PENDING), with SET_PERSONALITY() not actually setting the
personality, but just the "pending" bit, so that "flush_thread()" can do
the actual personality magic.

This patch in no way changes any of that insanity, but it does split the
'flush_old_exec()' function up into a preparatory part that can fail
(still called flush_old_exec()), and a new part that will actually set
up the new exec environment (setup_new_exec()).  All callers are changed
to trivially comply with the new world order.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Turned out to cause trouble on single IOH machines, and is superceded by
_CRS on multi-IOH machines with production BIOSes.
Signed-off-by: NJeff Garrett <jeff@jgarrett.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Dell OptiPlex 760 hangs on reboot unless reboot=bios is used.  Add quirk
to reboot through the BIOS.

BugLink: https://bugs.launchpad.net/bugs/488319Signed-off-by: NLeann Ogasawara <leann.ogasawara@canonical.com>
LKML-Reference: <1264634958.27335.1091.camel@emiko>
Cc: <stable@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

For SGI UV node controllers (HUB) rev 2.0 or greater, use
replicated cachelines to read the RTC timer.  This optimization
allows faster simulataneous reads from a given socket.
Signed-off-by: NDimitri Sivanich <sivanich@sgi.com>
Cc: Jack Steiner <steiner@sgi.com>
LKML-Reference: <20100122154140.GB4975@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Pass the number of minors when unregistering MSR and CPUID drivers.
Reported-by: NDean Nelson <dnelson@redhat.com>
Signed-off-by: NDean Nelson <dnelson@redhat.com>
LKML-Reference: <20100127023722.GA22305@sgi.com>
Signed-off-by: NRuss Anderson <rja@sgi.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Add Xeon 7500 series support to oprofile.

Straight forward: it's the same as Core i7, so just detect
the model number. No user space changes needed.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NRobert Richter <robert.richter@amd.com>

With multiplexing enabled oprofile crashs when profiling more than 28
events. This patch fixes this.
Signed-off-by: NSuravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: NRobert Richter <robert.richter@amd.com>

In function kvm_arch_vcpu_init(), if the memory malloc for
vcpu->arch.mce_banks is fail, it does not free the memory
of lapic date. This patch fixed it.

Cc: stable@kernel.org
Signed-off-by: NWei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

vcpu->arch.mce_banks is malloc in kvm_arch_vcpu_init(), but
never free in any place, this may cause memory leak. So this
patch fixed to free it in kvm_arch_vcpu_uninit().

Cc: stable@kernel.org
Signed-off-by: NWei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Exit the guest pagetable walk loop if reading gpte failed. Otherwise its
possible to enter an endless loop processing the previous present pte.

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

When found a error hva, should not return PAGE_SIZE but the level...

Also clean up the coding style of the following loop.

Cc: stable@kernel.org
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

When we queue an interrupt to the local apic, we set the IRR before the TMR.
The vcpu can pick up the IRR and inject the interrupt before setting the TMR,
and perhaps even EOI it, causing incorrect behaviour.

The race is really insignificant since it can only occur on the first
interrupt (usually following interrupts will not change TMR), but it's better
closed than open.

Fixed by reordering setting the TMR vs IRR.

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

CONFIG_X86_CPU_DEBUG, which provides some parsed versions of the x86
CPU configuration via debugfs, has caused boot failures on real
hardware.  The value of this feature has been marginal at best, as all
this information is already available to userspace via generic
interfaces.

Causes crashes that have not been fixed + minimal utility -> remove.

See the referenced LKML thread for more information.
Reported-by: NOzan Çağlayan <ozan@pardus.org.tr>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
LKML-Reference: <alpine.LFD.2.00.1001221755320.13231@localhost.localdomain>
Cc: Jaswinder Singh Rajput <jaswinder@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: <stable@kernel.org>

Commit d1c84f79
leads to a regression when microcode_amd.c is compiled into the kernel.
It causes a big boot delay because the firmware is not available.
See http://marc.info/?l=linux-kernel&m=126267290920060

It also renders the reload sysfs attribute useless.
Fixing this is too intrusive for an -rc5 kernel.

Thus I'd like to restore the microcode loading behaviour of kernel
2.6.32.

CC: Gene Heskett <gene.heskett@verizon.net>
Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
LKML-Reference: <20100122203456.GB13792@alberich.amd.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

HPET MSI on platforms with ATI SB700/SB800 as they seem to have some
side-effects on floppy DMA. Do not use HPET MSI on such platforms.

Original problem report from Mark Hounschell
http://lkml.indiana.edu/hypermail/linux/kernel/0912.2/01118.html

[ This patch needs to go to stable as well. But, there are some
  conflicts that prevents the patch from going as is. I can
  rebase/resubmit to stable once the patch goes upstream.
  hpa: still Cc:'ing stable@ as an FYI. ]
Tested-by: NMark Hounschell <markh@compro.net>
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: <stable@kernel.org>
LKML-Reference: <20100121190952.GA32523@linux-os.sc.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

nodes_possible_map does not currently include nodes that have SRAT
entries that are all ACPI_SRAT_MEM_HOT_PLUGGABLE since the bit is
cleared in nodes_parsed if it does not have an online address range.

Unequivocally setting the bit in nodes_parsed is insufficient since
existing code, such as acpi_get_nodes(), assumes all nodes in the map
have online address ranges.  In fact, all code using nodes_parsed
assumes such nodes represent an address range of online memory.

nodes_possible_map is created by unioning nodes_parsed and
cpu_nodes_parsed; the former represents nodes with online memory and
the latter represents memoryless nodes.  We now set the bit for
hotpluggable nodes in cpu_nodes_parsed so that it also gets set in
nodes_possible_map.

[ hpa: Haicheng Li points out that this makes the naming of the
  variable cpu_nodes_parsed somewhat counterintuitive.  However, leave
  it as is in the interest of keeping the pure bug fix patch small. ]
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Tested-by: NHaicheng Li <haicheng.li@linux.intel.com>
LKML-Reference: <alpine.DEB.2.00.1001201152040.30528@chino.kir.corp.google.com>
Cc: <stable@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Deassigning a device from the passthrough domain does not
work and breaks device assignment to kvm guests. This patch
fixes the issue.

Cc: stable@kernel.org
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch moves the initialization of the iommu-api out of
the dma-ops initialization code. This ensures that the
iommu-api is initialized even with iommu=pt.

Cc: stable@kernel.org
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

In the __detach_device function the reference count for a
device-domain binding may become zero. This results in the
device being removed from the domain and dev_data->domain
will be NULL. This is bad because this pointer is
dereferenced when trying to unlock the domain->lock. This
patch fixes the issue by keeping the domain in a seperate
variable.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

The variable i in this function could be increased to over
2**32 which would result in an integer overflow when using
int. Fix it by changing i to unsigned long.

Cc: stable@kernel.org
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Propagate the ANY bit into the fixed counter config for v3 and higher.
Signed-off-by: NStephane Eranian <eranian@google.com>
[a.p.zijlstra@chello.nl: split from larger patch]
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4b5430c6.0f975e0a.1bf9.ffff85fe@mx.google.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We can use logical flat mode if there are <= 8 logical cpu's
(irrespective of physical apic id values).  This will enable simplified
and efficient IPI and device interrupt routing on such platforms.

This has been tested to work on both Intel and AMD platforms.
Exceptions like IBM summit platform which can't use logical flat mode
are addressed by using OEM platform checks.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Chris McDermott <lcm@linux.vnet.ibm.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Chris McDermott from IBM confirmed that hurricane chipset in IBM summit
platforms doesn't support logical flat mode.  Irrespective of the other
things like apic_id's, total number of logical cpu's, Linux kernel
should default to physical mode for this system.

The 32-bit kernel does so using the OEM checks for the IBM summit
platform.  Add a similar OEM platform check for the 64bit kernel too.

Otherwise the linux kernel boot can hang on this platform under certain
bios/platform settings.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Tested-by: NAnanth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Chris McDermott <lcm@linux.vnet.ibm.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 62edab90 (from June 2009
but merged in 2.6.33) changes notify_die to pass dr6 by
reference.

However, it forgets to fix the check for DR_STEP in kmmio.c,
breaking mmiotrace. It also passes a wrong value to the post
handler.

This simple fix makes mmiotrace work again.
Signed-off-by: NLuca Barbieri <luca@luca-barbieri.com>
Acked-by: NK.Prasad <prasad@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1263634770-14578-1-git-send-email-luca@luca-barbieri.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Ensure that UV hub revision is set for all ACPI modes.
Signed-off-by: NRuss Anderson <rja@sgi.com>
LKML-Reference: <20100115180908.GB7757@sgi.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Add function for determining the revision id of the SGI UV
node controller chip (HUB). This function is needed in a
subsequent patch.
Signed-off-by: NJack Steiner <steiner@sgi.com>
LKML-Reference: <20100112210904.GA24546@sgi.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Under Xen 64 bit guests actually run their kernel in ring 3,
however the hypervisor takes care of squashing descriptor the
RPLs transparently (in order to allow them to continue to
differentiate between user and kernel space CS using the RPL).
Therefore the Xen paravirt backend should use RPL==0 instead of
1 (or 3). Using RPL==1 causes generic arch code to take
incorrect code paths because it uses "testl $3, <CS>, je foo"
type tests for a userspace CS and this considers 1==userspace.

This issue was previously masked because get_kernel_rpl() was
omitted when setting CS in kernel_thread(). This was fixed when
kernel_thread() was unified with 32 bit in
f443ff42.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Cc: Christian Kujau <lists@nerdbynature.de>
Cc: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1263377768-19600-2-git-send-email-ian.campbell@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Before the kernel_thread was converted into "C" we had
pt_regs::ss set to __KERNEL_DS (by SAVE_ALL asm macro).

Though I must admit I didn't find any *explicit* load of
%ss from this structure the better to be on a safe side
and set it to a known value.
Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Cc: Christian Kujau <lists@nerdbynature.de>
Cc: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com>
Cc: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1263377768-19600-1-git-send-email-ian.campbell@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This fixes the regression introduced by the commit
f405d2c0.

The above commit fixes the following issue:

  http://marc.info/?l=linux-kernel&m=126192729110083&w=2

However, it doesn't work properly when you remove and insert the
agp_amd64 module again.

agp_amd64_init() and agp_amd64_cleanup should be called only
when gart_iommu is not called earlier (that is, the GART IOMMU
is not enabled). We need to use 'gart_iommu_aperture' to see if
GART IOMMU is enabled or not.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: mitov@issp.bas.bg
Cc: davej@redhat.com
LKML-Reference: <20100104161603L.fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This fixes the problem of the initialization code not correctly
mapping the entire MMIO space on a UV system.  A side effect is
the map_high() interface needed to be changed to accommodate
different address and size shifts.
Signed-off-by: NMike Travis <travis@sgi.com>
Reviewed-by: NMike Habeck <habeck@sgi.com>
Cc: <stable@kernel.org>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <4B479202.7080705@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Someone isn't reading their build output: Move the definition
out of the exported header.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: linux-kernel@vger.kernelorg
Signed-off-by: NIngo Molnar <mingo@elte.hu>

While processing kernel perf callchains, an bad entry can be
considered as a valid stack pointer but not as a kernel address.

In this case, we hang in an endless loop. This can happen in an
x86-32 kernel after processing the last entry in a kernel
stacktrace.

Just stop the stack frame walking after we encounter an invalid
kernel address.

This fixes a hard lockup in x86-32.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1262227945-27014-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Revert commit 2fbd07a5, as this commit
breaks an IBM platform with quad-core Xeon cpu's.

According to Suresh, this might be an IBM platform issue, as on other
Intel platforms with <= 8 logical cpu's, logical flat mode works fine
irespective of physical apic id values (inline with the xapic
architecture).

Revert this for now because of the IBM platform breakage.

Another version will be re-submitted after the complete analysis.
Signed-off-by: NAnanth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The list macros use LIST_POISON1 and LIST_POISON2 as undereferencable
pointers in order to trap erronous use of freed list_heads.  Unfortunately
userspace can arrange for those pointers to actually be dereferencable,
potentially turning an oops to an expolit.

To avoid this allow architectures (currently x86_64 only) to override
the default values for these pointers with truly-undereferencable values.
This is easy on x86_64 as the virtual address space is large and contains
areas that cannot be mapped.

Other 64-bit architectures will likely find similar unmapped ranges.

[ingo: switch to 0xdead000000000000 as the unmapped area]
[ingo: add comments, cleanup]
[jaswinder: eliminate sparse warnings]
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAvi Kivity <avi@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The necessary changes to the x86 Kconfig and boot/compressed to allow the
use of this new compression method
Signed-off-by: NAlbin Tonnerre <albin.tonnerre@free-electrons.com>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Tested-by: NWu Zhangjin <wuzhangjin@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Tested-by: NRussell King <rmk@arm.linux.org.uk>
Acked-by: NRussell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>