There's a fair amount of code in the vsyscall page.  It contains
a syscall instruction (in the gettimeofday fallback) and who
knows what will happen if an exploit jumps into the middle of
some other code.

Reduce the risk by replacing the vsyscalls with short magic
incantations that cause the kernel to emulate the real
vsyscalls. These incantations are useless if entered in the
middle.

This causes vsyscalls to be a little more expensive than real
syscalls.  Fortunately sensible programs don't use them.
The only exception is time() which is still called by glibc
through the vsyscall - but calling time() millions of times
per second is not sensible. glibc has this fixed in the
development tree.

This patch is not perfect: the vread_tsc and vread_hpet
functions are still at a fixed address.  Fixing that might
involve making alternative patching work in the vDSO.
Signed-off-by: NAndy Lutomirski <luto@mit.edu>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: richard -rw- weinberger <richard.weinberger@gmail.com>
Cc: Mikael Pettersson <mikpe@it.uu.se>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Louis Rilling <Louis.Rilling@kerlabs.com>
Cc: Valdis.Kletnieks@vt.edu
Cc: pageexec@freemail.hu
Link: http://lkml.kernel.org/r/e64e1b3c64858820d12c48fa739efbd1485e79d5.1307292171.git.luto@mit.edu
[ Removed the CONFIG option - it's simpler to just do it unconditionally. Tidied up the code as well. ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The commit 44259b1a
    Author: Andy Lutomirski <luto@MIT.EDU>
    x86-64: Move vread_tsc into a new file with sensible options

Removed the -pg from tsc.o which caused the function graph tracer
to go into an infinite function call recursion as it uses the tsc
internally outside its recursion protection, thus tracing the tsc
breaks the function graph tracer.

This commit also added the file vread_tsc_64.c that gets used
by vdso but failed to prevent GCOV from monkeying with it,
causing userspace to try to access kernel data when GCOV was
enabled.

Thanks to Thomas Gleixner for pointing out GCOV as the likely
culprit that added strange kernel accesses into the vread_tsc()
call.

Cc: Author: Andy Lutomirski <luto@MIT.EDU>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

vread_tsc is short and hot, and it's userspace code so the usual
reasons to enable -pg and turn off sibling calls don't apply.

(OK, turning off sibling calls has no effect.  But it might
someday...)

As an added benefit, tsc.c is profilable now.
Signed-off-by: NAndy Lutomirski <luto@mit.edu>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Borislav Petkov <bp@amd64.org>
Link: http://lkml.kernel.org/r/%3C99c6d7f5efa3ccb65b4ac6eb443e1ab7bad47d7b.1306156808.git.luto%40mit.edu%3ESigned-off-by: NThomas Gleixner <tglx@linutronix.de>

This file only contains code relevant for the northbridge
gart in AMD processors. This patch renames the file to
represent this fact in the filename.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

8237A utilizes the interface provided by CONFIG_ISA_DMA_API, specifically
claim_dma_lock() and release_dma_lock().  Thus, there's a strict
dependency on the config option and the module should only be loaded if
the kernel supports ISA-style DMA.
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The isci driver needs to retrieve its preboot OROM image which contains
necessary runtime parameters like platform specific sas addresses and
phy configuration.  There is no ROM BAR associated with this area,
instead we will need to scan legacy expansion ROM space.

1/ Promote the probe_roms_32 implementation to x86-64
2/ Add a facility to find and map an adapter rom by pci device (according to
   PCI Firmware Specification Revision 3.0)
Signed-off-by: NDave Jiang <dave.jiang@intel.com>
LKML-Reference: <20110308183226.6246.90354.stgit@localhost6.localdomain6>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

The extra tsc_sync.o goal definition is superflous.
CONFIG_X86_64_SMP depends on CONFIG_SMP
and tsc_sync.o is already in the definition of CONFIG_SMP.
Signed-off-by: NHenrik Kretzschmar <henne@nachtwindheim.de>
Acked-by: NCyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <1299826956-8607-1-git-send-email-henne@nachtwindheim.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch adds minimal support for device tree on x86. The device
tree blob is passed to the kernel via setup_data which requires at
least boot protocol 2.09.

Memory size, restricted memory regions, boot arguments are gathered
the traditional way so things like cmd_line are just here to let the
code compile.

The current plan is use the device tree as an extension and to gather
information which can not be enumerated and would have to be hardcoded
otherwise. This includes things like 
   - which devices are on this I2C/SPI bus?
   - how are the interrupts wired to IO APIC?
   - where could my hpet be?
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NDirk Brandewie <dirk.brandewie@gmail.com>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: sodaville@linutronix.de
Cc: devicetree-discuss@lists.ozlabs.org
LKML-Reference: <1298405266-1624-3-git-send-email-bigeasy@linutronix.de>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Move the real-mode reboot code out to an assembly file (reboot_32.S)
which is allocated using the common lowmem trampoline allocator.
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
LKML-Reference: <4D5DFBE4.7090104@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Matthieu Castet <castet.matthieu@free.fr>

Common infrastructure for low memory trampolines.  This code installs
the trampolines permanently in low memory very early.  It also permits
multiple pieces of code to be used for this purpose.

This code also introduces a standard infrastructure for computing
symbol addresses in the trampoline code.

The only change to the actual SMP trampolines themselves is that the
64-bit trampoline has been made reusable -- the previous version would
overwrite the code with a status variable; this moves the status
variable to a separate location.
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
LKML-Reference: <4D5DFBE4.7090104@intel.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Matthieu Castet <castet.matthieu@free.fr>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>

This implements arch_remove_reservations() so allocate_resource() can
avoid any arch-specific reserved areas.  This currently just avoids the
BIOS area (the first 1MB), but could be used for E820 reserved areas if
that turns out to be necessary.

We previously avoided this area in pcibios_align_resource().  This patch
moves the test from that PCI-specific path to a generic path, so *all*
resource allocations will avoid this area.
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Move the code to arch/x86/platform/mrst/. Also fix a typo to use
the correct config option: ONFIG_EARLY_PRINTK_MRST
Signed-off-by: NFeng Tang <feng.tang@intel.com>
Cc: alan@linux.intel.com
LKML-Reference: <1291348298-21263-1-git-send-email-feng.tang@intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

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

The Iris machines from Eurobraille do not have APM or ACPI support
to shut themselves down properly.  A special I/O sequence is
needed to do so.  This modle runs this I/O sequence at
kernel shutdown when its force parameter is set to 1.
Signed-off-by: NShérab <Sebastien.Hinderer@ens-lyon.org>
Acked-by: N"H. Peter Anvin" <hpa@zytor.com>
[ did minor coding style edits ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Andres Salomon <dilinger@queued.net>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Mike Travis <travis@sgi.com>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Jacob Pan <jacob.jun.pan@intel.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>

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

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

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Huang Ying <ying.huang@intel.com>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Len Brown <lenb@kernel.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>

Provide a mechanism that allows running code in IRQ context. It is
most useful for NMI code that needs to interact with the rest of the
system -- like wakeup a task to drain buffers.

Perf currently has such a mechanism, so extract that and provide it as
a generic feature, independent of perf so that others may also
benefit.

The IRQ context callback is generated through self-IPIs where
possible, or on architectures like powerpc the decrementer (the
built-in timer facility) is set to generate an interrupt immediately.

Architectures that don't have anything like this get to do with a
callback from the timer tick. These architectures can call
irq_work_run() at the tail of any IRQ handlers that might enqueue such
work (like the perf IRQ handler) to avoid undue latencies in
processing the work.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NKyle McMartin <kyle@mcmartin.ca>
Acked-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
[ various fixes ]
Signed-off-by: NHuang Ying <ying.huang@intel.com>
LKML-Reference: <1287036094.7768.291.camel@yhuang-dev>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This file is unused since the apic unification in 2.6.29, but nobody
noticed.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Add a pm_power_off handler for the OLPC XO-1 laptop.

The driver can be built modular and follows the behaviour of the
APM driver, setting pm_power_off to NULL on unload. However, the
ability to unload the module will probably be removed (with a simple
__module_get(THIS_MODULE)) if/when XO-1 suspend/resume support is
added to this file at a later date.
Signed-off-by: NDaniel Drake <dsd@laptop.org>
LKML-Reference: <20101010094032.9AE669D401B@zog.reactivated.net>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Intel Moorestown platform has a spi-uart device(Maxim3110),
which connects to a Designware spi core controller. This patch
will add early console function based on it.

As it will be used long before Linux spi subsystem get
initialised, we simply directly manipulate the spi controller's
register to acheive the early console func. This is safe as it
will be disabled when devices subsytem get initialised.

To use it, user need enable CONFIG_X86_MRST_EARLY_PRINTK in
kenrel config and add "earlyprintk=mrst" in kernel command line.
Signed-off-by: NFeng Tang <feng.tang@intel.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
Cc: greg@kroah.com
LKML-Reference: <1284361736-23011-4-git-send-email-feng.tang@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The guest can use the paravirt clock in kvmclock.c which is used
by sched_clock(), which in turn is used by the tracing mechanism
for timestamps, which leads to infinite recursion.

Disable mcount/tracing for kvmclock.o.

Cc: stable@kernel.org
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

When using a paravirt clock, pvclock.c can be used by sched_clock(),
which in turn is used by the tracing mechanism for timestamps,
which leads to infinite recursion.

Disable mcount/tracing for pvclock.o.

Cc: stable@kernel.org
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
LKML-Reference: <4C9A9A3F.4040201@goop.org>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

add x86 support for jump label. I'm keeping this patch separate so its clear
to arch maintainers what was required for x86 support this new feature.
Hopefully, it wouldn't be too painful for other archs.
Signed-off-by: NJason Baron <jbaron@redhat.com>
LKML-Reference: <f838f49f40fbea0254036194be66dc48b598dcea.1284733808.git.jbaron@redhat.com>

[ cleaned up some formatting ]
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

The file names are somehow misleading as the code is not specific to
AMD K8 CPUs anymore. The files accomodate code for other AMD CPU
northbridges as well.

Same is true for the config option which is valid for AMD CPU
northbridges in general and not specific to K8.
Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
LKML-Reference: <20100917160343.GD4958@loge.amd.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

We are using a very simple sort routine which sorts the .iommu_table
array in the order of dependencies. Specifically each structure
of iommu_table_entry has a field 'depend' which contains the function
pointer to the IOMMU that MUST be run before us. We sort the array
of structures so that the struct iommu_table_entry with no
'depend' field are first, and then the subsequent ones are the
ones for which the 'depend' function has been already invoked
(in other words, precede us).

Using the kernel's version 'sort', which is a mergeheap is
feasible, but would require making the comparison operator
scan recursivly the array to satisfy the "heapify" process: setting the
levels properly. The end result would much more complex than it should
be an it is just much simpler to utilize this simple sort routine.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
LKML-Reference: <1282845485-8991-4-git-send-email-konrad.wilk@oracle.com>
CC: H. Peter Anvin <hpa@zytor.com>
CC: Fujita Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

With the recent innovations in CPU hardware acceleration technologies
from Intel and AMD, VMware ran a few experiments to compare these
techniques to guest paravirtualization technique on VMware's platform.
These hardware assisted virtualization techniques have outperformed the
performance benefits provided by VMI in most of the workloads. VMware
expects that these hardware features will be ubiquitous in a couple of
years, as a result, VMware has started a phased retirement of this
feature from the hypervisor.

Please note that VMI has always been an optimization and non-VMI kernels
still work fine on VMware's platform.
Latest versions of VMware's product which support VMI are,
Workstation 7.0 and VSphere 4.0 on ESX side, future maintainence
releases for these products will continue supporting VMI.

For more details about VMI retirement take a look at this,
http://blogs.vmware.com/guestosguide/2009/09/vmi-retirement.html

This feature removal was scheduled for 2.6.37 back in September 2009.
Signed-off-by: NAlok N Kataria <akataria@vmware.com>
LKML-Reference: <1282600151.19396.22.camel@ank32.eng.vmware.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Add support for saving OFW's cif, and later calling into it to run OFW
commands.  OFW remains resident in memory, living within virtual range
0xff800000 - 0xffc00000.  A single page directory entry points to the
pgdir that OFW actually uses, so rather than saving the entire page
table, we grab and install that one entry permanently in the kernel's
page table.

This is currently only used by the OLPC XO.  Note that this particular
calling convention breaks PAE and PAT, and so cannot be used on newer
x86 hardware.
Signed-off-by: NAndres Salomon <dilinger@queued.net>
LKML-Reference: <20100618174653.7755a39a@dev.queued.net>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Support for the PMU's BTS features has been upstreamed in
v2.6.32, but we still have the old and disabled ptrace-BTS,
as Linus noticed it not so long ago.

It's buggy: TIF_DEBUGCTLMSR is trampling all over that MSR without
regard for other uses (perf) and doesn't provide the flexibility
needed for perf either.

Its users are ptrace-block-step and ptrace-bts, since ptrace-bts
was never used and ptrace-block-step can be implemented using a
much simpler approach.

So axe all 3000 lines of it. That includes the *locked_memory*()
APIs in mm/mlock.c as well.
Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Markus Metzger <markus.t.metzger@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <20100325135413.938004390@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

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>

This makes the range reservation feature available to other
architectures.

-v2: add get_max_mapped, max_pfn_mapped only defined in x86...
     to fix PPC compiling
-v3: according to hpa, add CONFIG_HAVE_EARLY_RES
-v4: fix typo about EARLY_RES in config
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4B7B5723.4070009@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

... to make e820.c smaller.

-v2: fix 32bit compiling with MAX_DMA32_PFN
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-21-git-send-email-yinghai@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

With generic modular drivers handling all of this stuff, the
geode-specific code can go away.  The cs5535-gpio, cs5535-mfgpt, and
cs5535-clockevt drivers now handle this.
Signed-off-by: NAndres Salomon <dilinger@collabora.co.uk>
Cc: Jordan Crouse <jordan@cosmicpenguin.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Chris Ball <cjb@laptop.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Moorestown MID devices need to be detected early in the boot process
to setup and do not call x86_default_early_setup as there is no EBDA
region to reserve.

[ Copied the minimal code from Jacobs latest MRST series ]
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Jacob Pan <jacob.jun.pan@intel.com>

Remove the redundant copy.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/sfi.c serves the dual-purpose of supporting the
SFI core with arch specific code, as well as a home for the
arch-specific code that uses SFI.

analogous to ACPI, drivers/sfi/Kconfig is pulled in by arch/x86/Kconfig
Signed-off-by: NFeng Tang <feng.tang@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>
Cc: x86@kernel.org