virtio has been so far used only in the context of virtualization,
and the virtio Kconfig was sourced directly by the relevant arch
Kconfigs when VIRTUALIZATION was selected.

Now that we start using virtio for inter-processor communications,
we need to source the virtio Kconfig outside of the virtualization
scope too.

Moreover, some architectures might use virtio for both virtualization
and inter-processor communications, so directly sourcing virtio
might yield unexpected results due to conflicting selections.

The simple solution offered by this patch is to always source virtio's
Kconfig in drivers/Kconfig, and remove it from the appropriate arch
Kconfigs. Additionally, a virtio menu entry has been added so virtio
drivers don't show up in the general drivers menu.

This way anyone can use virtio, though it's arguably less accessible
(and neat!) for virtualization users now.

Note: some architectures (mips and sh) seem to have a VIRTUALIZATION
menu merely for sourcing virtio's Kconfig, so that menu is removed too.
Signed-off-by: NOhad Ben-Cohen <ohad@wizery.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

The comment is outdated, wikipedia now has six translations of the cpuid
page.
Signed-off-by: NAdrian Knoth <adi@drcomp.erfurt.thur.de>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

This patch fixes three typos I've accidentally spotted.
Signed-off-by: NAdrian Knoth <adi@drcomp.erfurt.thur.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (one was already fixed)

Also removes a long-unused #define and an extraneous semicolon.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

We switch back from using vmcall in 091ebf07
because it was unreliable under kvm, but I missed one (rarely-used) place.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

The Host used to create some page tables for the Guest to use at the
top of Guest memory; it would then tell the Guest where this was.  In
particular, it created linear mappings for 0 and 0xC0000000 addresses
because lguest used to switch to its real page tables quite late in
boot.

However, since d50d8fe1 Linux initialized boot page tables in
head_32.S even before the "are we lguest?" boot jump.  So, now we can
simplify things: the Host pagetable code assumes 1:1 linear mapping
until it first calls the LHCALL_NEW_PGTABLE hypercall, which we now do
before we reach C code.

This also means that the Host doesn't need to know anything about the
Guest's PAGE_OFFSET.  (Non-Linux guests might not even have such a
thing).
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

We can map the vDSO straight from kernel data, saving a few page
allocations.  As an added bonus, the deleted code contained a memory
leak.
Signed-off-by: NAndy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/2c4ed5c2c2e93603790229e0c3403ae506ccc0cb.1311277573.git.luto@mit.eduSigned-off-by: NH. Peter Anvin <hpa@zytor.com>

The machinery for __ARCH_HAS_CLOCKSOURCE_DATA assumed a file in
asm-generic would be the default for architectures without their own
file in asm/, but that is not how it works.

Replace it with a Kconfig option instead.

Link: http://lkml.kernel.org/r/4E288AA6.7090804@zytor.comSigned-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@mit.edu>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Tony Luck <tony.luck@intel.com>

Yet another variant of the Dell Latitude series which requires
reboot=pci.

From the E5420 bug report by Daniel J Blueman:

> The E6420 is affected also (same platform, different casing and
> features), which provides an external confirmation of the issue; I can
> submit a patch for that later or include it if you prefer:
> http://linux.koolsolutions.com/2009/08/04/howto-fix-linux-hangfreeze-during-reboots-and-restarts/Reported-by: NDaniel J Blueman <daniel.blueman@gmail.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org>

Rebooting on the Dell E5420 often hangs with the keyboard or ACPI
methods, but is reliable via the PCI method.

[ hpa: this was deferred because we believed for a long time that the
  recent reshuffling of the boot priorities in commit
  660e34ce fixed this platform.
  Unfortunately that turned out to be incorrect. ]
Signed-off-by: NDaniel J Blueman <daniel.blueman@gmail.com>
Link: http://lkml.kernel.org/r/1305248699-2347-1-git-send-email-daniel.blueman@gmail.comSigned-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org>

copy_from_user_nmi() is used in oprofile and perf. Moving it to other
library functions like copy_from_user(). As this is x86 code for 32
and 64 bits, create a new file usercopy.c for unified code.
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110607172413.GJ20052@erda.amd.comSigned-off-by: NIngo Molnar <mingo@elte.hu>

This patch:

 - fixes typos in comments and clarifies the text
 - renames obscure p4_event_alias::original and ::alter members to
   ::original and ::alternative as appropriate
 - drops parenthesis from the return of p4_get_alias_event()

No functional changes.
Reported-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org>
Link: http://lkml.kernel.org/r/20110721160625.GX7492@sunSigned-off-by: NIngo Molnar <mingo@elte.hu>

This array is read-only. Make it explicit by marking as const.
Signed-off-by: NGreg Dietsche <Gregory.Dietsche@cuw.edu>
Link: http://lkml.kernel.org/r/1309482653-23648-1-git-send-email-Gregory.Dietsche@cuw.eduSigned-off-by: NIngo Molnar <mingo@elte.hu>

The EFI specification requires that callers of the time related
runtime functions serialize with other CMOS accesses in the
kernel, as the EFI time functions may choose to also use the
legacy CMOS RTC.

Besides fixing a latent bug, this is a prerequisite to safely
enable the rtc-efi driver for x86, which ought to be preferred
over rtc-cmos on all EFI platforms.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Acked-by: NMatthew Garrett <mjg59@srcf.ucam.org>
Cc: <mjg@redhat.com>
Link: http://lkml.kernel.org/r/4E257E33020000780004E319@nat28.tlf.novell.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
Cc: Matthew Garrett <mjg@redhat.com>

With CPU hotplug, there is a theoretical race between other CMOS
(namely RTC) accesses and those done in the SMP secondary
processor bringup path.

I am unware of the problem having been noticed by anyone in practice,
but it would very likely be rather spurious and very hard to reproduce.
So to be on the safe side, acquire rtc_lock around those accesses.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/4E257AE7020000780004E2FF@nat28.tlf.novell.comSigned-off-by: NIngo Molnar <mingo@elte.hu>

With the write lock path simply subtracting RW_LOCK_BIAS there
is, on large systems, the theoretical possibility of overflowing
the 32-bit value that was used so far (namely if 128 or more
CPUs manage to do the subtraction, but don't get to do the
inverse addition in the failure path quickly enough).

A first measure is to modify RW_LOCK_BIAS itself - with the new
value chosen, it is good for up to 2048 CPUs each allowed to
nest over 2048 times on the read path without causing an issue.
Quite possibly it would even be sufficient to adjust the bias a
little further, assuming that allowing for significantly less
nesting would suffice.

However, as the original value chosen allowed for even more
nesting levels, to support more than 2048 CPUs (possible
currently only for 64-bit kernels) the lock itself gets widened
to 64 bits.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4E258E0D020000780004E3F0@nat28.tlf.novell.comSigned-off-by: NIngo Molnar <mingo@elte.hu>

Rather than having two functionally identical implementations
for 32- and 64-bit configurations, use the previously extended
assembly abstractions to fold the rwsem two implementations into
a shared one.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4E258DF3020000780004E3ED@nat28.tlf.novell.comSigned-off-by: NIngo Molnar <mingo@elte.hu>

Rather than having two functionally identical implementations
for 32- and 64-bit configurations, extend the existing assembly
abstractions enough to fold the two rwlock implementations into
a shared one.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4E258DD7020000780004E3EA@nat28.tlf.novell.comSigned-off-by: NIngo Molnar <mingo@elte.hu>

Now that 1b3f2a72 is in, it is very
important that the below lying comment be removed! :-)
Signed-off-by: NBorislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20110718191054.GA18359@liondog.tnicAcked-by: NAndy Lutomirski <luto@mit.edu>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Fix the printk_once() so that it actually prints (didn't print before
due to a stray comma.)

[ hpa: changed to an incremental patch and adjusted the description
  accordingly. ]
Signed-off-by: NLen Brown <len.brown@intel.com>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1107151732480.18606@x980
Cc: <table@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

handle_signal()->set_fs() has a nice comment which explains what
set_fs() is, but it doesn't explain why it is needed and why it
depends on CONFIG_X86_64.

Afaics, the history of this confusion is:

	1. I guess today nobody can explain why it was needed
	   in arch/i386/kernel/signal.c, perhaps it was always
	   wrong. This predates 2.4.0 kernel.

	2. then it was copy-and-past'ed to the new x86_64 arch.

	3. then it was removed from i386 (but not from x86_64)
	   by b93b6ca3 "i386: remove unnecessary code".

	4. then it was reintroduced under CONFIG_X86_64 when x86
	   unified i386 and x86_64, because the patch above didn't
	   touch x86_64.

Remove it. ->addr_limit should be correct. Even if it was possible
that it is wrong, it is too late to fix it after setup_rt_frame().

Linus commented in:
http://lkml.kernel.org/r/alpine.LFD.0.999.0707170902570.19166@woody.linux-foundation.org

... about the equivalent bit from i386:

Heh. I think it's entirely historical.

Please realize that the whole reason that function is called "set_fs()" is 
that it literally used to set the %fs segment register, not 
"->addr_limit".

So I think the "set_fs(USER_DS)" is there _only_ to match the other

        regs->xds = __USER_DS;
        regs->xes = __USER_DS;
        regs->xss = __USER_DS;
        regs->xcs = __USER_CS;

things, and never mattered. And now it matters even less, and has been 
copied to all other architectures where it is just totally insane.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20110710164424.GA20261@redhat.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

1. do_signal() looks at TS_RESTORE_SIGMASK and calculates the
   mask which should be stored in the signal frame, then it
   passes "oldset" to the callees, down to setup_rt_frame().

   This is ugly, setup_rt_frame() can do this itself and nobody
   else needs this sigset_t. Move this code into setup_rt_frame.

2. do_signal() also clears TS_RESTORE_SIGMASK if handle_signal()
   succeeds.

   We can move this to setup_rt_frame() as well, this avoids the
   unnecessary checks and makes the logic more clear.

3. use set_current_blocked() instead of sigprocmask(SIG_SETMASK),
   sigprocmask() should be avoided.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20110710182203.GA27979@redhat.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

sys_sigsuspend() and sys_sigreturn() change ->blocked directly.
This is not correct, see the changelog in e6fa16ab
"signal: sigprocmask() should do retarget_shared_pending()"

Change them to use set_current_blocked().
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20110710192727.GA31759@redhat.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

sys32_sigsuspend() and sys32_*sigreturn() change ->blocked directly.
This is not correct, see the changelog in e6fa16ab
"signal: sigprocmask() should do retarget_shared_pending()"

Change them to use set_current_blocked().
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20110710192724.GA31755@redhat.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

The vsyscall page now consists entirely of trap instructions.

Cc: John Stultz <johnstul@us.ibm.com>
Signed-off-by: NAndy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/637648f303f2ef93af93bae25186e9a1bea093f5.1310639973.git.luto@mit.eduSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Fix a trivial typo in the name of the constant
ENERGY_PERF_BIAS_POWERSAVE.  This didn't cause trouble because this
constant is not currently used for anything.
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: Len Brown <len.brown@intel.com>
Link: http://lkml.kernel.org/r/tip-abe48b108247e9b90b4c6739662a2e5c765ed114@git.kernel.org

Instead of hw_nmi_watchdog_set_attr() weak function
and appropriate x86_pmu::hw_watchdog_set_attr() call
we introduce even alias mechanism which allow us
to drop this routines completely and isolate quirks
of Netburst architecture inside P4 PMU code only.

The main idea remains the same though -- to allow
nmi-watchdog and perf top run simultaneously.

Note the aliasing mechanism applies to generic
PERF_COUNT_HW_CPU_CYCLES event only because arbitrary
event (say passed as RAW initially) might have some
additional bits set inside ESCR register changing
the behaviour of event and we can't guarantee anymore
that alias event will give the same result.

P.S. Thanks a huge to Don and Steven for for testing
     and early review.
Acked-by: NDon Zickus <dzickus@redhat.com>
Tested-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org>
CC: Ingo Molnar <mingo@elte.hu>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: Stephane Eranian <eranian@google.com>
CC: Lin Ming <ming.m.lin@intel.com>
CC: Arnaldo Carvalho de Melo <acme@redhat.com>
CC: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20110708201712.GS23657@sunSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>

Since 2.6.36 (23016bf0), Linux prints the existence of "epb" in /proc/cpuinfo,
Since 2.6.38 (d5532ee7), the x86_energy_perf_policy(8) utility has
been available in-tree to update MSR_IA32_ENERGY_PERF_BIAS.

However, the typical BIOS fails to initialize the MSR, presumably
because this is handled by high-volume shrink-wrap operating systems...

Linux distros, on the other hand, do not yet invoke x86_energy_perf_policy(8).
As a result, WSM-EP, SNB, and later hardware from Intel will run in its
default hardware power-on state (performance), which assumes that users
care for performance at all costs and not for energy efficiency.
While that is fine for performance benchmarks, the hardware's intended default
operating point is "normal" mode...

Initialize the MSR to the "normal" by default during kernel boot.

x86_energy_perf_policy(8) is available to change the default after boot,
should the user have a different preference.
Signed-off-by: NLen Brown <len.brown@intel.com>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1107140051020.18606@x980Acked-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@kernel.org>

The vread field was bloating struct clocksource everywhere except
x86_64, and I want to change the way this works on x86_64, so let's
split it out into per-arch data.

Cc: x86@kernel.org
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: linux-ia64@vger.kernel.org
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/3ae5ec76a168eaaae63f08a2a1060b91aa0b7759.1310563276.git.luto@mit.eduSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

This gives much nicer diagnostics when something goes wrong.  It's
supported at least as far back as binutils 2.15.
Signed-off-by: NAndy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/de0b50920469ff6359c529526e7639fdd36fa83c.1310563276.git.luto@mit.eduSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

This code is short enough and different enough from the module
loader that it's not worth trying to share anything.
Signed-off-by: NAndy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/e73112e4381fff29e31b882c2d0856822edaea53.1310563276.git.luto@mit.eduSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

This save a few bytes on x86-64 and means that future patches can
apply alternatives to unrelocated code.
Signed-off-by: NAndy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/ff64a6b9a1a3860ca4a7b8b6dc7b4754f9491cd7.1310563276.git.luto@mit.eduSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Three fixes here:
 - Send SIGSEGV if called from compat code or with a funny CS.
 - Don't BUG on impossible addresses.
 - Add a missing local_irq_disable.

This patch also removes an unused variable.
Signed-off-by: NAndy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/6fb2b13ab39b743d1e4f466eef13425854912f7f.1310563276.git.luto@mit.eduSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

SPARSEMEM w/o VMEMMAP and DISCONTIGMEM, both used only on 32bit, use
sections array to map pfn to nid which is limited in granularity.  If
NUMA nodes are laid out such that the mapping cannot be accurate, boot
will fail triggering BUG_ON() in mminit_verify_page_links().

On 32bit, it's 512MiB w/ PAE and SPARSEMEM.  This seems to have been
granular enough until commit 2706a0bf (x86, NUMA: Enable
CONFIG_AMD_NUMA on 32bit too).  Apparently, there is a machine which
aligns NUMA nodes to 128MiB and has only AMD NUMA but not SRAT.  This
led to the following BUG_ON().

 On node 0 totalpages: 2096615
   DMA zone: 32 pages used for memmap
   DMA zone: 0 pages reserved
   DMA zone: 3927 pages, LIFO batch:0
   Normal zone: 1740 pages used for memmap
   Normal zone: 220978 pages, LIFO batch:31
   HighMem zone: 16405 pages used for memmap
   HighMem zone: 1853533 pages, LIFO batch:31
 BUG: Int 6: CR2   (null)
      EDI   (null)  ESI 00000002  EBP 00000002  ESP c1543ecc
      EBX f2400000  EDX 00000006  ECX   (null)  EAX 00000001
      err   (null)  EIP c16209aa   CS 00000060  flg 00010002
 Stack: f2400000 00220000 f7200800 c1620613 00220000 01000000 04400000 00238000
          (null) f7200000 00000002 f7200b58 f7200800 c1620929 000375fe   (null)
        f7200b80 c16395f0 00200a02 f7200a80   (null) 000375fe 00000002   (null)
 Pid: 0, comm: swapper Not tainted 2.6.39-rc5-00181-g2706a0bf #17
 Call Trace:
  [<c136b1e5>] ? early_fault+0x2e/0x2e
  [<c16209aa>] ? mminit_verify_page_links+0x12/0x42
  [<c1620613>] ? memmap_init_zone+0xaf/0x10c
  [<c1620929>] ? free_area_init_node+0x2b9/0x2e3
  [<c1607e99>] ? free_area_init_nodes+0x3f2/0x451
  [<c1601d80>] ? paging_init+0x112/0x118
  [<c15f578d>] ? setup_arch+0x791/0x82f
  [<c15f43d9>] ? start_kernel+0x6a/0x257

This patch implements node_map_pfn_alignment() which determines
maximum internode alignment and update numa_register_memblks() to
reject NUMA configuration if alignment exceeds the pfn -> nid mapping
granularity of the memory model as determined by PAGES_PER_SECTION.

This makes the problematic machine boot w/ flatmem by rejecting the
NUMA config and provides protection against crazy NUMA configurations.
Signed-off-by: NTejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20110712074534.GB2872@htj.dyndns.org
LKML-Reference: <20110628174613.GP478@escobedo.osrc.amd.com>
Reported-and-Tested-by: NHans Rosenfeld <hans.rosenfeld@amd.com>
Cc: Conny Seidel <conny.seidel@amd.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

DISCONTIGMEM on x86-32 implements pfn -> nid mapping similarly to
SPARSEMEM; however, it calls each mapping unit ELEMENT instead of
SECTION.  This patch renames it to SECTION so that PAGES_PER_SECTION
is valid for both DISCONTIGMEM and SPARSEMEM.  This will be used by
the next patch to implement mapping granularity check.

This patch is trivial constant rename.
Signed-off-by: NTejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20110712074422.GA2872@htj.dyndns.org
Cc: Hans Rosenfeld <hans.rosenfeld@amd.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

The Dell Latitude E6320 doesn't reboot unless reboot=pci is set.
Force it thanks to DMI.
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Link: http://lkml.kernel.org/r/1309269451-4966-1-git-send-email-maxime.ripard@free-electrons.com
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

When IR (interrupt remapping) is enabled print_IO_APIC() displays output according
to legacy RTE (redirection table entry) definitons:

 NR Dst Mask Trig IRR Pol Stat Dmod Deli Vect:
 00 00  1    0    0   0   0    0    0    00
 01 00  0    0    0   0   0    0    0    01
 02 00  0    0    0   0   0    0    0    02
 03 00  1    0    0   0   0    0    0    03
 04 00  1    0    0   0   0    0    0    04
 05 00  1    0    0   0   0    0    0    05
 06 00  1    0    0   0   0    0    0    06
...

The above output is as per Sec 3.2.4 of the IOAPIC datasheet:
82093AA I/O Advanced Programmable Interrupt Controller (IOAPIC):
http://download.intel.com/design/chipsets/datashts/29056601.pdf

Instead the output should display the fields as discussed in Sec 5.5.1
of the VT-d specification:

(Intel Virtualization Technology for Directed I/O:
http://download.intel.com/technology/computing/vptech/Intel(r)_VT_for_Direct_IO.pdf)

After the fix:
 NR Indx Fmt Mask Trig IRR Pol Stat Indx2 Zero Vect:
 00 0000 0   1    0    0   0   0    0     0    00
 01 000F 1   0    0    0   0   0    0     0    01
 02 0001 1   0    0    0   0   0    0     0    02
 03 0002 1   1    0    0   0   0    0     0    03
 04 0011 1   1    0    0   0   0    0     0    04
 05 0004 1   1    0    0   0   0    0     0    05
 06 0005 1   1    0    0   0   0    0     0    06
...
Signed-off-by: NNaga Chumbalkar <nagananda.chumbalkar@hp.com>
Link: http://lkml.kernel.org/r/20110712211658.2939.93123.sendpatchset@nchumbalkar.americas.cpqcorp.netSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

When "apic=debug" is used as a boot parameter, Linux prints the IOAPIC routing
entries in "dmesg". Below is output from IOAPIC whose apic_id is 8:

# dmesg | grep "routing entry"
IOAPIC[8]: Set routing entry (8-1 -> 0x31 -> IRQ 1 Mode:0 Active:0 Dest:0)
IOAPIC[8]: Set routing entry (8-2 -> 0x30 -> IRQ 0 Mode:0 Active:0 Dest:0)
IOAPIC[8]: Set routing entry (8-3 -> 0x33 -> IRQ 3 Mode:0 Active:0 Dest:0)
...

Similarly, when IR (interrupt remapping) is enabled, and the IRTE
(interrupt remapping table entry) is set up we should display it.

After the fix:

# dmesg | grep IRTE
IOAPIC[8]: Set IRTE entry (P:1 FPD:0 Dst_Mode:0 Redir_hint:1 Trig_Mode:0 Dlvry_Mode:0 Avail:0 Vector:31 Dest:00000000 SID:00F1 SQ:0 SVT:1)
IOAPIC[8]: Set IRTE entry (P:1 FPD:0 Dst_Mode:0 Redir_hint:1 Trig_Mode:0 Dlvry_Mode:0 Avail:0 Vector:30 Dest:00000000 SID:00F1 SQ:0 SVT:1)
IOAPIC[8]: Set IRTE entry (P:1 FPD:0 Dst_Mode:0 Redir_hint:1 Trig_Mode:0 Dlvry_Mode:0 Avail:0 Vector:33 Dest:00000000 SID:00F1 SQ:0 SVT:1)
...

The IRTE is defined in Sec 9.5 of the Intel VT-d Specification.
Signed-off-by: NNaga Chumbalkar <nagananda.chumbalkar@hp.com>
Link: http://lkml.kernel.org/r/20110712211704.2939.71291.sendpatchset@nchumbalkar.americas.cpqcorp.netSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

If there's no special reason to zero-out the "high" 32-bits of the IA32_APIC_BASE
MSR, let's preserve it.

The x2APIC Specification doesn't explicitly state any such requirement. (Sec 2.2
in: http://www.intel.com/Assets/PDF/manual/318148.pdf).
Signed-off-by: NNaga Chumbalkar <nagananda.chumbalkar@hp.com>
Link: http://lkml.kernel.org/r/20110712055831.2498.78521.sendpatchset@nchumbalkar.americas.cpqcorp.netReviewed-by: NCyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Somehow we got into a situation where the __this_cpu_xchg() operations were
not defined in the same way as this_cpu_xchg() and friends. I had some build
failures under 32 bit that were addressed by these fixes.
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NTejun Heo <tj@kernel.org>