The number of BIOSes that have an option to enable the IOMMU, or fix
anything about its configuration, is vanishingly small. There's no good
reason to punish quiet boot for this.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On x86_64 the gdb serial register structure defines the PS (also known
as eflags), CS and SS registers as 4 bytes entities.
This patch splits the x86_64 regnames enum into a 32 and 64 version to
account for the 32 bit entities in the gdb serial packets.
Also the program counter is properly filled in for the sleeping
threads.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
The BX and DX registers in the gdb serial register packet need to be
flipped for gdb to receive the correct data.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Impact: System hang when AMD C1E machines switch into C2/C3
AMD C1E enabled systems do not work with normal ACPI C-states
even if the BIOS is advertising them. Limit the C-states to
C1 for the ACPI processor idle code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Impact: hang which happens across CPU offline/online on AMD C1E systems.
When a CPU goes offline then the corresponding bit in the broadcast
mask is cleared. For AMD C1E enabled CPUs we do not reenable the
broadcast when the CPU comes online again as we do not clear the
corresponding bit in the c1e_mask, which keeps track which CPUs
have been switched to broadcast already. So on those !$@#& machines
we never switch back to broadcasting after a CPU offline/online cycle.
Clear the bit when the CPU plays dead.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There's a small window when NMI watchdog is being set up that if any NMIs
are triggered, the NMI code will make make use of not initalized wd_ops
elements:
void setup_apic_nmi_watchdog(void *unused)
{
if (__get_cpu_var(wd_enabled))
return;
/* cheap hack to support suspend/resume */
/* if cpu0 is not active neither should the other cpus */
if (smp_processor_id() != 0 && atomic_read(&nmi_active) <= 0)
return;
switch (nmi_watchdog) {
case NMI_LOCAL_APIC:
/* enable it before to avoid race with handler */
--> __get_cpu_var(wd_enabled) = 1;
--> if (lapic_watchdog_init(nmi_hz) < 0) {
(...)
asmlinkage notrace __kprobes void default_do_nmi(struct pt_regs *regs)
{
(...)
if (nmi_watchdog_tick(regs, reason))
return;
(...)
notrace __kprobes int
nmi_watchdog_tick(struct pt_regs *regs, unsigned reason)
{
(...)
if (!__get_cpu_var(wd_enabled))
return rc;
switch (nmi_watchdog) {
case NMI_LOCAL_APIC:
rc |= lapic_wd_event(nmi_hz);
(...)
int lapic_wd_event(unsigned nmi_hz)
{
struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);
u64 ctr;
--> rdmsrl(wd->perfctr_msr, ctr);
and wd->*_msr will be initialized on each processor type specific setup, after
enabling NMIs for PMIs. Since the counter was just set, the chances of an
performance counter generated NMI is minimal, but any other unknown NMI would
trigger the problem. This patch fixes the problem by setting everything up
before enabling performance counter generated NMIs and will set wd_enabled
using a callback function.
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
According to the documentation gpio_free should only be called from task
context only. To make this more explicit add a might sleep to all
implementations.
This patch changes the gpio_free implementations for the x86
architecture.
Signed-off-by: Uwe Kleine-König <ukleinek@informatik.uni-freiburg.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
pte_pfn() has always been of type unsigned long, even on 32-bit PAE;
but in the current tip/next/mm tree it works out to be unsigned long
long on 64-bit, which gives an irritating warning if you try to printk
a pfn with the usual %lx.
Now use the same pte_pfn() function, moved from pgtable-3level.h
to pgtable.h, for all models: as suggested by Jeremy Fitzhardinge.
And pte_page() can well move along with it (remaining a macro to
avoid dependence on mm_types.h).
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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: H. Peter Anvin <hpa@zytor.com>
The x86-tracehook code now contains this line in syscall_get_error():
return error >= -4095L ? error : 0;
Hard-wiring a constant is not nice. Let's use the IS_ERR_VALUE macro
from linux/err.h instead.
Signed-off-by: Petr Tesarik <ptesarik@suse.cz>
Cc: utrace-devel@redhat.com
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: bogus error codes (+other?) on x86-64
The rdmsr_safe/wrmsr_safe routines have macros for the handling of the
edx:eax arguments. Those macros take a variable number of assembly
arguments. This is rather inherently incompatible with using
%digit-style escapes in the inline assembly; replace those with
%[name]-style escapes.
This fixes miscompilation on x86-64, which at the very least caused
bogus return values. It is possible that this could also corrupt the
return value; I am not sure.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Propagate error (-ENXIO) from smp_call_function_single(). These
errors can happen when a CPU is unplugged while the MSR driver is
open.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: add X86_FEATURE_XMM4_2 definitions
x86: fix cpufreq + sched_clock() regression
x86: fix HPET regression in 2.6.26 versus 2.6.25, check hpet against BAR, v3
x86: do not enable TSC notifier if we don't need it
x86 MCE: Fix CPU hotplug problem with multiple multicore AMD CPUs
x86: fix: make PCI ECS for AMD CPUs hotplug capable
x86: fix: do not run code in amd_bus.c on non-AMD CPUs
Added Intel processor SSE4.2 feature flag.
No in-tree user at the moment, but makes the tree-merging life easier
for the crypto tree.
Signed-off-by: Austin Zhang <austin.zhang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
vmlinux.lds expects the fixup code to be on a section named .fixup. The
.text.fixup section is not mentioned on vmlinux.lds, and is included on
the resulting vmlinux (just after .text) only because of ld heuristics on
placing orphan sections.
However, placing .text.fixup outside .text breaks the definition of
_etext, making it exclude the .text.fixup contents. That makes .text.fixup
be ignored by the kernel initialization code that needs to know about
section locations, such as the code setting page protection bits.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch lets the files using linux/version.h match the files that
#include it.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
During CPU hot-remove the sysfs directory created by
threshold_create_bank(), defined in
arch/x86/kernel/cpu/mcheck/mce_amd_64.c, has to be removed before
its parent directory, created by mce_create_device(), defined in
arch/x86/kernel/cpu/mcheck/mce_64.c . Moreover, when the CPU in
question is hotplugged again, obviously the latter has to be created
before the former. At present, the right ordering is not enforced,
because all of these operations are carried out by CPU hotplug
notifiers which are not appropriately ordered with respect to each
other. This leads to serious problems on systems with two or more
multicore AMD CPUs, among other things during suspend and hibernation.
Fix the problem by placing threshold bank CPU hotplug callbacks in
mce_cpu_callback(), so that they are invoked at the right places,
if defined. Additionally, use kobject_del() to remove the sysfs
directory associated with the kobject created by
kobject_create_and_add() in threshold_create_bank(), to prevent the
kernel from crashing during CPU hotplug operations on systems with
two or more multicore AMD CPUs.
This patch fixes bug #11337.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Andi Kleen <andi@firstfloor.org>
Tested-by: Mark Langsdorf <mark.langsdorf@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
WARNING: vmlinux.o(.cpuinit.text+0x3cc4): Section mismatch in reference from the function uv_cpu_init() to the function .init.text:uv_system_init()
The function __cpuinit uv_cpu_init() references
a function __init uv_system_init().
If uv_system_init is only used by uv_cpu_init then
annotate uv_system_init with a matching annotation.
uv_system_init was ment to be called only once, so do it from codepath
(native_smp_prepare_cpus) which is called once, right before activation
of other cpus (smp_init).
Note: old code relied on uv_node_to_blade being initialized to 0,
but it'a not initialized from anywhere.
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Acked-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch changes the pfn args from 'u32' to 'unsigned long'
on alloc_p*() functions on paravirt_ops, and the corresponding
implementations for Xen and VMI. The prototypes for CONFIG_PARAVIRT=n
are already using unsigned long, so paravirt.h now matches the prototypes
on asm-x86/pgalloc.h.
It shouldn't result in any changes on generated code on 32-bit, with
or without CONFIG_PARAVIRT. On both cases, 'codiff -f' didn't show any
change after applying this patch.
On 64-bit, there are (expected) binary changes only when CONFIG_PARAVIRT
is enabled, as the patch is really supposed to change the size of the
pfn args.
[ v2: KVM_GUEST: use the right parameter type on kvm_release_pt() ]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Acked-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Booting kernel with vmalloc=[any size<=16m] will oops on my pc (i386/1G memory).
BUG_ON in arch/x86/mm/init_32.c triggered:
BUG_ON((unsigned long)high_memory > VMALLOC_START);
It's due to the vm area hole.
In include/asm-x86/pgtable_32.h:
#define VMALLOC_OFFSET (8 * 1024 * 1024)
#define VMALLOC_START (((unsigned long)high_memory + 2 * VMALLOC_OFFSET - 1) \
& ~(VMALLOC_OFFSET - 1))
There's several related point:
1. MAXMEM :
(-__PAGE_OFFSET - __VMALLOC_RESERVE).
The space after VMALLOC_END is included as well, I set it to
(VMALLOC_END - PAGE_OFFSET - __VMALLOC_RESERVE)
2. VMALLOC_OFFSET is not considered in __VMALLOC_RESERVE
fixed by adding VMALLOC_OFFSET to it.
3. VMALLOC_START :
(((unsigned long)high_memory + 2 * VMALLOC_OFFSET - 1) & ~(VMALLOC_OFFSET - 1))
So it's not always 8M, bigger than 8M possible.
I set it to ((unsigned long)high_memory + VMALLOC_OFFSET)
4. the VMALLOC_RESERVE is an unused macro, so remove it here.
Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Cc: akpm@linux-foundation.org
Cc: hidave.darkstar@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The UV TLB shootdown mechanism needs a system interrupt vector.
Its vector had been hardcoded as 200, but needs to moved to the reserved
system vector range so that it does not collide with some device vector.
This is still temporary until dynamic system IRQ allocation is provided.
But it will be needed when real UV hardware becomes available and runs 2.6.27.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use savesegment and loadsegment consistently in ia32 compat code.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Rename _ASM_MOV_UL to _ASM_MOV for consistency with other _ASM_
instructions (_ASM_ADD, _ASM_SUB and so on.)
Add ASM_SP, _ASM_BP, _ASM_SI, and _ASM_DI for consistency with
_ASM_[ABCD]X.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Quoting Mike Travis in "x86: cleanup early per cpu variables/accesses v4"
(23ca4bba3e):
The DEFINE macro defines the per_cpu variable as well as the early
map and pointer. It also initializes the per_cpu variable and map
elements to "_initvalue". The early_* macros provide access to
the initial map (usually setup during system init) and the early
pointer. This pointer is initialized to point to the early map
but is then NULL'ed when the actual per_cpu areas are setup. After
that the per_cpu variable is the correct access to the variable.
As these variables are NULL'ed before __init sections are dropped
(in setup_per_cpu_maps), they can be safely annotated as __ref.
This change silences following section mismatch warnings:
WARNING: vmlinux.o(.data+0x46c0): Section mismatch in reference from the variable x86_cpu_to_apicid_early_ptr to the variable .init.data:x86_cpu_to_apicid_early_map
The variable x86_cpu_to_apicid_early_ptr references
the variable __initdata x86_cpu_to_apicid_early_map
If the reference is valid then annotate the
variable with __init* (see linux/init.h) or name the variable:
*driver, *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console,
WARNING: vmlinux.o(.data+0x46c8): Section mismatch in reference from the variable x86_bios_cpu_apicid_early_ptr to the variable .init.data:x86_bios_cpu_apicid_early_map
The variable x86_bios_cpu_apicid_early_ptr references
the variable __initdata x86_bios_cpu_apicid_early_map
If the reference is valid then annotate the
variable with __init* (see linux/init.h) or name the variable:
*driver, *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console,
WARNING: vmlinux.o(.data+0x46d0): Section mismatch in reference from the variable x86_cpu_to_node_map_early_ptr to the variable .init.data:x86_cpu_to_node_map_early_map
The variable x86_cpu_to_node_map_early_ptr references
the variable __initdata x86_cpu_to_node_map_early_map
If the reference is valid then annotate the
variable with __init* (see linux/init.h) or name the variable:
*driver, *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console,
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
WARNING: arch/x86/kernel/built-in.o(.cpuinit.text+0x1591): Section mismatch in reference from the function init_amd() to the function .init.text:check_enable_amd_mmconf_dmi()
The function __cpuinit init_amd() references
a function __init check_enable_amd_mmconf_dmi().
If check_enable_amd_mmconf_dmi is only used by init_amd then
annotate check_enable_amd_mmconf_dmi with a matching annotation.
check_enable_amd_mmconf_dmi is only called from init_amd which is __cpuinit
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
x86_64 add/sub atomic ops does not seems to accept integer values bigger
than 32 bits as immediates. Intel's add/sub documentation specifies they
have to be passed as registers.
The only operations in the x86-64 architecture which accept arbitrary
64-bit immediates is "movq" to any register; similarly, the only
operation which accept arbitrary 64-bit displacement is "movabs" to or
from al/ax/eax/rax.
http://gcc.gnu.org/onlinedocs/gcc-4.3.0/gcc/Machine-Constraints.html
states :
e
32-bit signed integer constant, or a symbolic reference known to fit
that range (for immediate operands in sign-extending x86-64
instructions).
Z
32-bit unsigned integer constant, or a symbolic reference known to
fit that range (for immediate operands in zero-extending x86-64
instructions).
Since add/sub does sign extension, using the "e" constraint seems appropriate.
It applies to 2.6.27-rc, 2.6.26, 2.6.25...
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (32 commits)
x86: add MAP_STACK mmap flag
x86: fix section mismatch warning - spp_getpage()
x86: change init_gdt to update the gdt via write_gdt, rather than a direct write.
x86-64: fix overlap of modules and fixmap areas
x86, geode-mfgpt: check IRQ before using MFGPT as clocksource
x86, acpi: cleanup, temp_stack is used only when CONFIG_SMP is set
x86: fix spin_is_contended()
x86, nmi: clean UP NMI watchdog failure message
x86, NMI: fix watchdog failure message
x86: fix /proc/meminfo DirectMap
x86: fix readb() et al compile error with gcc-3.2.3
arch/x86/Kconfig: clean up, experimental adjustement
x86: invalidate caches before going into suspend
x86, perfctr: don't use CCCR_OVF_PMI1 on Pentium 4Ds
x86, AMD IOMMU: initialize dma_ops after sysfs registration
x86m AMD IOMMU: cleanup: replace LOW_U32 macro with generic lower_32_bits
x86, AMD IOMMU: initialize device table properly
x86, AMD IOMMU: use status bit instead of memory write-back for completion wait
x86: silence mmconfig printk
x86, msr: fix NULL pointer deref due to msr_open on nonexistent CPUs
...
Since we are now using DS prefixes instead of NOP to remove LOCK
prefixes, there is no longer any problems with instruction boundaries
moving around.
* Linus Torvalds (torvalds@linux-foundation.org) wrote:
>
>
> On Thu, 14 Aug 2008, Mathieu Desnoyers wrote:
> >
> > Changing the 0x90 (single-byte nop) currently used into a 0x3E DS segment
> > override prefix should fix this issue. Since the default of the atomic
> > instructions is to use the DS segment anyway, it should not affect the
> > behavior.
>
> Ok, so I think this is an _excellent_ patch, but I'd like to also then use
> LOCK_PREFIX in include/asm-x86/futex.h.
>
> See commit 9d55b9923a.
>
> Linus
Unless there a rationale for this, I think these be changed to LOCK_PREFIX
too.
grep "lock ;" include/asm-x86/spinlock.h
"lock ; cmpxchgw %w1,%2\n\t"
asm volatile("lock ; xaddl %0, %1\n"
"lock ; cmpxchgl %1,%2\n\t"
Applies to 2.6.27-rc2.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: H. Peter Anvin <hpa@zytor.com>
CC: Jeremy Fitzhardinge <jeremy@goop.org>
CC: Roland McGrath <roland@redhat.com>
CC: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
CC: Steven Rostedt <srostedt@redhat.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: David Miller <davem@davemloft.net>
CC: Ulrich Drepper <drepper@redhat.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Gregory Haskins <ghaskins@novell.com>
CC: Arnaldo Carvalho de Melo <acme@redhat.com>
CC: "Luis Claudio R. Goncalves" <lclaudio@uudg.org>
CC: Clark Williams <williams@redhat.com>
CC: Christoph Lameter <cl@linux-foundation.org>
CC: Andi Kleen <andi@firstfloor.org>
CC: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Since we now use DS prefixes instead of NOP to remove LOCK prefixes,
there are no longer any issues with instruction boundaries moving around.
Depends on :
x86 alternatives : fix LOCK_PREFIX race with preemptible kernel and CPU hotplug
On Thu, 14 Aug 2008, Mathieu Desnoyers wrote:
>
> Changing the 0x90 (single-byte nop) currently used into a 0x3E DS segment
> override prefix should fix this issue. Since the default of the atomic
> instructions is to use the DS segment anyway, it should not affect the
> behavior.
Ok, so I think this is an _excellent_ patch, but I'd like to also then use
LOCK_PREFIX in include/asm-x86/futex.h.
See commit 9d55b9923a.
Linus
Applies to 2.6.27-rc2 (and -rc3 unless hell broke loose in futex.h between rc2
and rc3).
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: H. Peter Anvin <hpa@zytor.com>
CC: Jeremy Fitzhardinge <jeremy@goop.org>
CC: Roland McGrath <roland@redhat.com>
CC: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
CC: Steven Rostedt <srostedt@redhat.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: David Miller <davem@davemloft.net>
CC: Ulrich Drepper <drepper@redhat.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Gregory Haskins <ghaskins@novell.com>
CC: Arnaldo Carvalho de Melo <acme@redhat.com>
CC: "Luis Claudio R. Goncalves" <lclaudio@uudg.org>
CC: Clark Williams <williams@redhat.com>
CC: Christoph Lameter <cl@linux-foundation.org>
CC: Andi Kleen <andi@firstfloor.org>
CC: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
as per this discussion:
http://lkml.org/lkml/2008/8/12/423
Pardo reported that 64-bit threaded apps, if their stacks exceed the
combined size of ~4GB, slow down drastically in pthread_create() - because
glibc uses MAP_32BIT to allocate the stacks. The use of MAP_32BIT is
a legacy hack - to speed up context switching on certain early model
64-bit P4 CPUs.
So introduce a new flag to be used by glibc instead, to not constrain
64-bit apps like this.
glibc can switch to this new flag straight away - it will be ignored
by the kernel. If those old CPUs ever matter to anyone, support for
it can be implemented.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Ulrich Drepper <drepper@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
as per this discussion:
http://lkml.org/lkml/2008/8/12/423
Pardo reported that 64-bit threaded apps, if their stacks exceed the
combined size of ~4GB, slow down drastically in pthread_create() - because
glibc uses MAP_32BIT to allocate the stacks. The use of MAP_32BIT is
a legacy hack - to speed up context switching on certain early model
64-bit P4 CPUs.
So introduce a new flag to be used by glibc instead, to not constrain
64-bit apps like this.
glibc can switch to this new flag straight away - it will be ignored
by the kernel. If those old CPUs ever matter to anyone, support for
it can be implemented.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Ulrich Drepper <drepper@gmail.com>
