Make the GDT_ENTRY() macro in  <asm/segment.h> safe for use in
assembly code by guarding the ULL suffixes with _AC() macros.
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>

Use the unified trampoline allocation setup to allocate and install
the ACPI wakeup code in low memory.
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>

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>

The "Type 2" SMBIOS record that contains Board Name is not
strictly required and may be absent in the SMBIOS on some
platforms.

( Please note that Type 2 is not listed in Table 3 in Sec 6.2
  ("Required Structures and Data") of the SMBIOS v2.7
  Specification. )

Use the Manufacturer Name (aka System Vendor) name.
Print Board Name only when it is present.

Before the fix:
  (i) dmesg output: DMI: /ProLiant DL380 G6, BIOS P62 01/29/2011
 (ii) oops output:  Pid: 2170, comm: bash Not tainted 2.6.38-rc4+ #3 /ProLiant DL380 G6

After the fix:
  (i) dmesg output: DMI: HP ProLiant DL380 G6, BIOS P62 01/29/2011
 (ii) oops output:  Pid: 2278, comm: bash Not tainted 2.6.38-rc4+ #4 HP ProLiant DL380 G6
Signed-off-by: NNaga Chumbalkar <nagananda.chumbalkar@hp.com>
Reviewed-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Cc: <stable@kernel.org> # .3x - good for debugging, please apply as far back as it applies cleanly
LKML-Reference: <20110214224423.2182.13929.sendpatchset@nchumbalkar.americas.hpqcorp.net>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

mp_find_ioapic() prints errors like:

    ERROR: Unable to locate IOAPIC for GSI 13

if it can't find the IOAPIC that manages that specific GSI. I
see errors like that at every boot of a laptop that apparently
doesn't have any IOAPICs.

But if there are no IOAPICs it doesn't seem to be an error that
none can be found. A solution that gets rid of this message is
to directly return if nr_ioapics (still) is zero. (But keep
returning -1 in that case, so nothing breaks from this change.)

The call chain that generates this error is:

pnpacpi_allocated_resource()
    case ACPI_RESOURCE_TYPE_IRQ:
        pnpacpi_parse_allocated_irqresource()
            acpi_get_override_irq()
                 mp_find_ioapic()
Signed-off-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We use it in non __cpuinit code now too so drop marker.
Signed-off-by: NBorislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <20110211171754.GA21047@aftab>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

commit a3c08e5d(x86: Convert irq_chip access to new functions)
accidentally zapped desc = irq_to_desc(irq); in the vector loop.
So we lock some random irq descriptor.

Add it back.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: <stable@kernel.org> # .37

Fix this deadlock - we are already holding the mutex:

=======================================================
[ INFO: possible circular locking dependency detected ] 2.6.38-rc4-test+ #1
-------------------------------------------------------
bash/1850 is trying to acquire lock:
 (text_mutex){+.+.+.}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f

but task is already holding lock:
 (smp_alt){+.+...}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (smp_alt){+.+...}:
       [<ffffffff81082d02>] lock_acquire+0xcd/0xf8
       [<ffffffff8192e119>] __mutex_lock_common+0x4c/0x339
       [<ffffffff8192e4ca>] mutex_lock_nested+0x3e/0x43
       [<ffffffff8101050f>] alternatives_smp_switch+0x77/0x1d8
       [<ffffffff81926a6f>] do_boot_cpu+0xd7/0x762
       [<ffffffff819277dd>] native_cpu_up+0xe6/0x16a
       [<ffffffff81928e28>] _cpu_up+0x9d/0xee
       [<ffffffff81928f4c>] cpu_up+0xd3/0xe7
       [<ffffffff82268d4b>] kernel_init+0xe8/0x20a
       [<ffffffff8100ba24>] kernel_thread_helper+0x4/0x10

-> #1 (cpu_hotplug.lock){+.+.+.}:
       [<ffffffff81082d02>] lock_acquire+0xcd/0xf8
       [<ffffffff8192e119>] __mutex_lock_common+0x4c/0x339
       [<ffffffff8192e4ca>] mutex_lock_nested+0x3e/0x43
       [<ffffffff810568cc>] get_online_cpus+0x41/0x55
       [<ffffffff810a1348>] stop_machine+0x1e/0x3e
       [<ffffffff819314c1>] text_poke_smp_batch+0x3a/0x3c
       [<ffffffff81932b6c>] arch_optimize_kprobes+0x10d/0x11c
       [<ffffffff81933a51>] kprobe_optimizer+0x152/0x222
       [<ffffffff8106bb71>] process_one_work+0x1d3/0x335
       [<ffffffff8106cfae>] worker_thread+0x104/0x1a4
       [<ffffffff810707c4>] kthread+0x9d/0xa5
       [<ffffffff8100ba24>] kernel_thread_helper+0x4/0x10

-> #0 (text_mutex){+.+.+.}:

other info that might help us debug this:

6 locks held by bash/1850:
 #0:  (&buffer->mutex){+.+.+.}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f
 #1:  (s_active#75){.+.+.+}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f
 #2:  (x86_cpu_hotplug_driver_mutex){+.+.+.}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f
 #3:  (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f
 #4:  (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f
 #5:  (smp_alt){+.+...}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f

stack backtrace:
Pid: 1850, comm: bash Not tainted 2.6.38-rc4-test+ #1
Call Trace:

 [<ffffffff81080eb2>] print_circular_bug+0xa8/0xb7
 [<ffffffff8192e4ca>] mutex_lock_nested+0x3e/0x43
 [<ffffffff81010302>] alternatives_smp_unlock+0x3d/0x93
 [<ffffffff81010630>] alternatives_smp_switch+0x198/0x1d8
 [<ffffffff8102568a>] native_cpu_die+0x65/0x95
 [<ffffffff818cc4ec>] _cpu_down+0x13e/0x202
 [<ffffffff8117a619>] sysfs_write_file+0x108/0x144
 [<ffffffff8111f5a2>] vfs_write+0xac/0xff
 [<ffffffff8111f7a9>] sys_write+0x4a/0x6e
Reported-by: NSteven Rostedt <rostedt@goodmis.org>
Tested-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: mathieu.desnoyers@efficios.com
Cc: rusty@rustcorp.com.au
Cc: ananth@in.ibm.com
Cc: masami.hiramatsu.pt@hitachi.com
Cc: fweisbec@gmail.com
Cc: jbeulich@novell.com
Cc: jbaron@redhat.com
Cc: mhiramat@redhat.com
LKML-Reference: <1297458466.5226.93.camel@laptop>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Additionally doing things conditionally upon smp_processor_id()
being zero is generally a bad idea, as this means CPU 0 cannot
be offlined and brought back online later again.

While there may be other places where this is done, I think adding
more of those should be avoided so that some day SMP can really
become "symmetrical".
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
LKML-Reference: <4D525C7E0200007800030EE1@vpn.id2.novell.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The gs_index loading code uses the swapgs instruction to
switch to the user gs_base temporarily. This is unsave in an
lightweight exit-path in KVM on AMD because the
KERNEL_GS_BASE MSR is switches lazily. An NMI happening in
the critical path of load_gs_index may use the wrong GS_BASE
value then leading to unpredictable behavior, e.g. a
triple-fault.

This patch fixes the issue by making sure that load_gs_index
is called only with a valid KERNEL_GS_BASE value loaded in
KVM.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

We reserve lowmem for the things that need it, like the ACPI
wakeup code, way early to guarantee availability.  This happens
before we set up the proper pagetables, so set_memory_x() has no
effect.

Until we have a better solution, use an initcall to mark the
wakeup code executable.
Originally-by: NMatthieu Castet <castet.matthieu@free.fr>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: Matthias Hopf <mhopf@suse.de>
Cc: rjw@sisk.pl
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <4D4F8019.2090104@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Since checkin ebba638a we call
verify_cpu even in 32-bit mode.  Unfortunately, calling a function
means using the stack, and the stack pointer was not initialized in
the 32-bit setup code!  This code initializes the stack pointer, and
simplifies the interface slightly since it is easier to rely on just a
pointer value rather than a descriptor; we need to have different
values for the segment register anyway.

This retains start_stack as a virtual address, even though a physical
address would be more convenient for 32 bits; the 64-bit code wants
the other way around...
Reported-by: NMatthieu Castet <castet.matthieu@free.fr>
LKML-Reference: <4D41E86D.8060205@free.fr>
Tested-by: NKees Cook <kees.cook@canonical.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Clearing the cpu in prev's mm_cpumask early will avoid the flush tlb
IPI's while the cr3 is still pointing to the prev mm.  And this window
can lead to the possibility of bogus TLB fills resulting in strange
failures.  One such problematic scenario is mentioned below.

 T1. CPU-1 is context switching from mm1 to mm2 context and got a NMI
     etc between the point of clearing the cpu from the mm_cpumask(mm1)
     and before reloading the cr3 with the new mm2.

 T2. CPU-2 is tearing down a specific vma for mm1 and will proceed with
     flushing the TLB for mm1.  It doesn't send the flush TLB to CPU-1
     as it doesn't see that cpu listed in the mm_cpumask(mm1).

 T3. After the TLB flush is complete, CPU-2 goes ahead and frees the
     page-table pages associated with the removed vma mapping.

 T4. CPU-2 now allocates those freed page-table pages for something
     else.

 T5. As the CR3 and TLB caches for mm1 is still active on CPU-1, CPU-1
     can potentially speculate and walk through the page-table caches
     and can insert new TLB entries.  As the page-table pages are
     already freed and being used on CPU-2, this page walk can
     potentially insert a bogus global TLB entry depending on the
     (random) contents of the page that is being used on CPU-2.

 T6. This bogus TLB entry being global will be active across future CR3
     changes and can result in weird memory corruption etc.

To avoid this issue, for the prev mm that is handing over the cpu to
another mm, clear the cpu from the mm_cpumask(prev) after the cr3 is
changed.

Marking it for -stable, though we haven't seen any reported failure that
can be attributed to this.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Acked-by: NIngo Molnar <mingo@elte.hu>
Cc: stable@kernel.org	[v2.6.32+]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Markus Kohn ran into a hard hang regression on an acer aspire
1310, when acpi is enabled. git bisect showed the following
commit as the bad one that introduced the boot regression.

	commit d0af9eed
	Author: Suresh Siddha <suresh.b.siddha@intel.com>
	Date:   Wed Aug 19 18:05:36 2009 -0700

	    x86, pat/mtrr: Rendezvous all the cpus for MTRR/PAT init

Because of the UP configuration of that platform,
native_smp_prepare_cpus() bailed out (in smp_sanity_check())
before doing the set_mtrr_aps_delayed_init()

Further down the boot path, native_smp_cpus_done() will call the
delayed MTRR initialization for the AP's (mtrr_aps_init()) with
mtrr_aps_delayed_init not set. This resulted in the boot
processor reprogramming its MTRR's to the values seen during the
start of the OS boot. While this is not needed ideally, this
shouldn't have caused any side-effects. This is because the
reprogramming of MTRR's (set_mtrr_state() that gets called via
set_mtrr()) will check if the live register contents are
different from what is being asked to write and will do the actual
write only if they are different.

BP's mtrr state is read during the start of the OS boot and
typically nothing would have changed when we ask to reprogram it
on BP again because of the above scenario on an UP platform. So
on a normal UP platform no reprogramming of BP MTRR MSR's
happens and all is well.

However, on this platform, bios seems to be modifying the fixed
mtrr range registers between the start of OS boot and when we
double check the live registers for reprogramming BP MTRR
registers. And as the live registers are modified, we end up
reprogramming the MTRR's to the state seen during the start of
the OS boot.

During ACPI initialization, something in the bios (probably smi
handler?) don't like this fact and results in a hard lockup.

We didn't see this boot hang issue on this platform before the
commit d0af9eed, because only
the AP's (if any) will program its MTRR's to the value that BP
had at the start of the OS boot.

Fix this issue by checking mtrr_aps_delayed_init before
continuing further in the mtrr_aps_init(). Now, only AP's (if
any) will program its MTRR's to the BP values during boot.

Addresses https://bugzilla.novell.com/show_bug.cgi?id=623393

  [ By the way, this behavior of the bios modifying MTRR's after the start
    of the OS boot is not common and the kernel is not prepared to
    handle this situation well. Irrespective of this issue, during
    suspend/resume, linux kernel will try to reprogram the BP's MTRR values
    to the values seen during the start of the OS boot. So suspend/resume might
    be already broken on this platform for all linux kernel versions. ]
Reported-and-bisected-by: NMarkus Kohn <jabber@gmx.org>
Tested-by: NMarkus Kohn <jabber@gmx.org>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: Thomas Renninger <trenn@novell.com>
Cc: Rafael Wysocki <rjw@novell.com>
Cc: Venkatesh Pallipadi <venki@google.com>
Cc: stable@kernel.org # [v2.6.32+]
LKML-Reference: <1296694975.4418.402.camel@sbsiddha-MOBL3.sc.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Xen want page table pages read only.

But the initial page table (from head_*.S) live in .data or .bss.

That was broken by 64edc8ed.  There is
absolutely no reason to force these pages RW after they have already
been marked RO.
Signed-off-by: NMatthieu CASTET <castet.matthieu@free.fr>
Tested-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

This patch fixes some issues with raw event validation on
Pentium 4 (Netburst) based processors.

As I was testing libpfm4 Netburst support, I ran into two
problems in the p4_validate_raw_event() function:

   - the shared field must be checked ONLY when HT is on
   - the binding to ESCR register was missing

The second item was causing raw events to not be encoded
correctly compared to generic PMU events.

With this patch, I can now pass Netburst events to libpfm4
examples and get meaningful results:

  $ task -e global_power_events:running:u  noploop 1
  noploop for 1 seconds
  3,206,304,898 global_power_events:running
Signed-off-by: NStephane Eranian <eranian@google.com>
Acked-by: NCyrill Gorcunov <gorcunov@openvz.org>
Cc: peterz@infradead.org
Cc: paulus@samba.org
Cc: davem@davemloft.net
Cc: fweisbec@gmail.com
Cc: perfmon2-devel@lists.sf.net
Cc: eranian@gmail.com
Cc: robert.richter@amd.com
Cc: acme@redhat.com
Cc: gorcunov@gmail.com
Cc: ming.m.lin@intel.com
LKML-Reference: <4d3efb2f.1252d80a.1a80.ffffc83f@mx.google.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

With this patch, the cpuidle driver does not load and
does not issue the mwait operations. Instead the hypervisor
is doing them (b/c we call the safe_halt pvops call).

This fixes quite a lot of bootup issues wherein the user had
to force interrupts for the continuation of the bootup.

Details are discussed in:

http://lists.xensource.com/archives/html/xen-devel/2011-01/msg00535.html

[v2: Wrote the commit description]
Reported-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Tested-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Under Dell Inspiron 1525, and Intel SandyBridge SDP's the
BIOS e820 RAM is not page-aligned:

[   0.000000]  Xen: 0000000000100000 - 00000000df66d800 (usable)

We were not handling that and ended up setting up a pagetable
that included up to df66e000 with the disastrous effect that when

        memset(NODE_DATA(nodeid), 0, sizeof(pg_data_t));

tried to clear the page it would crash at the 2K mark.

Initially reported by Michael Young @
http://lists.xensource.com/archives/html/xen-devel/2011-01/msg00108.html

The fix is to page-align the size and also take into consideration
the start of the E820 (in case that is not page-aligned either). This
fixes the bootup failure on those affected machines.

This patch is a rework of the Micheal A Young initial patch and
considers the case if the start is not page-aligned.
Reported-by: NMichael A Young <m.a.young@durham.ac.uk>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NMichael A Young <m.a.young@durham.ac.uk>

In case the mfn_list does not have enough entries to fill
a p2m page we do not want the entries from max_pfn up to
the boundary to be filled with unknown values. Hence
set them to INVALID_P2M_ENTRY.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

These recent percpu commits:

  2485b646: x86,percpu: Move out of place 64 bit ops into X86_64 section
  8270137a: cpuops: Use cmpxchg for xchg to avoid lock semantics

Caused this 'perf top' crash:

 Kernel panic - not syncing: Fatal exception in interrupt
 Pid: 0, comm: swapper Tainted: G     D
 2.6.38-rc2-00181-gef71723 #413 Call Trace: <IRQ> [<ffffffff810465b5>]
    ? panic
    ? kmsg_dump
    ? kmsg_dump
    ? oops_end
    ? no_context
    ? __bad_area_nosemaphore
    ? perf_output_begin
    ? bad_area_nosemaphore
    ? do_page_fault
    ? __task_pid_nr_ns
    ? perf_event_tid
    ? __perf_event_header__init_id
    ? validate_chain
    ? perf_output_sample
    ? trace_hardirqs_off
    ? page_fault
    ? irq_work_run
    ? update_process_times
    ? tick_sched_timer
    ? tick_sched_timer
    ? __run_hrtimer
    ? hrtimer_interrupt
    ? account_system_vtime
    ? smp_apic_timer_interrupt
    ? apic_timer_interrupt
 ...

Looking at assembly code, I found:

list = this_cpu_xchg(irq_work_list, NULL);

gives this wrong code : (gcc-4.1.2 cross compiler)

ffffffff810bc45e:
	mov    %gs:0xead0,%rax
	cmpxchg %rax,%gs:0xead0
	jne    ffffffff810bc45e <irq_work_run+0x3e>
	test   %rax,%rax
	je     ffffffff810bc4aa <irq_work_run+0x8a>

Tell gcc we dirty eax/rax register in percpu_xchg_op()

Compiler must use another register to store pxo_new__

We also dont need to reload percpu value after a jump,
since a 'failed' cmpxchg already updated eax/rax

Wrong generated code was :
	xor     %rax,%rax   /* load 0 into %rax */
1:	mov     %gs:0xead0,%rax
	cmpxchg %rax,%gs:0xead0
	jne     1b
	test    %rax,%rax

After patch :

	xor     %rdx,%rdx   /* load 0 into %rdx */
	mov     %gs:0xead0,%rax
1:	cmpxchg %rdx,%gs:0xead0
	jne     1b:
	test    %rax,%rax
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Tejun Heo <tj@kernel.org>
LKML-Reference: <1295973114.3588.312.camel@edumazet-laptop>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Left-over from the x86 merge ...
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4D3E23D1.7010405@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This fixes TRANSPARENT_HUGEPAGE=y with PARAVIRT=y and HIGHMEM64=n.

The #ifdef that this patch removes was erratically introduced to fix a
build error for noPAE (where pmd.pmd doesn't exist).  So then the kernel
built but it failed at runtime because set_pmd_at was a noop.  This will
correct it by enabling set_pmd_at for noPAE mode too.
Signed-off-by: NAndrea Arcangeli <aarcange@redhat.com>
Reported-by: Nwerner <w.landgraf@ru.ru>
Reported-by: NMinchan Kim <minchan.kim@gmail.com>
Tested-by: NMinchan Kim <minchan.kim@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In arch/x86/kernel/dumpstack_64.c::dump_trace() we have this code:

...
  		if (!stack) {
  			unsigned long dummy;
  			stack = &dummy;
  			if (task && task != current)
  				stack = (unsigned long *)task->thread.sp;
  		}

  		bp = stack_frame(task, regs);
  		/*
  		 * Print function call entries in all stacks, starting at the
  		 * current stack address. If the stacks consist of nested
  		 * exceptions
  		 */
  		tinfo = task_thread_info(task);

  		for (;;) {
  			char *id;
  			unsigned long *estack_end;
  			estack_end = in_exception_stack(cpu, (unsigned long)stack,
  							&used, &id);
...

You'll notice that we assign to 'stack' the address of the variable
'dummy' which is only in-scope inside the 'if (!stack)'. So when we later
access stack (at the end of the above, and assuming we did not take the
'if (task && task != current)' branch) we'll be using the address of a
variable that is no longer in scope. I believe this patch is the proper
fix, but I freely admit that I'm not 100% certain.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
LKML-Reference: <alpine.LNX.2.00.1101242232590.10252@swampdragon.chaosbits.net>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

If we use jump table in module init, there are marked
as removed in __jump_table section after init is done.

But we already applied ro permissions on the module, so
we can't modify a read only section (crash in
remove_jump_label_module_init).

Make the __jump_table section rw.
Signed-off-by: NMatthieu CASTET <castet.matthieu@free.fr>
Cc: Xiaotian Feng <xtfeng@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Siarhei Liakh <sliakh.lkml@gmail.com>
Cc: Xuxian Jiang <jiang@cs.ncsu.edu>
Cc: James Morris <jmorris@namei.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Dave Jones <davej@redhat.com>
Cc: Kees Cook <kees.cook@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4D3C3F20.7030203@free.fr>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

ea530692 made a CPU use monitor/mwait
when offline. This is not the optimal choice for AMD wrt to powersavings
and we'd prefer our cores to halt (i.e. enter C1) instead. For this, the
same selection whether to use monitor/mwait has to be used as when we
select the idle routine for the machine.

With this patch, offlining cores 1-5 on a X6 machine allows core0 to
boost again.

[ hpa: putting this in urgent since it is a (power) regression fix ]
Reported-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
Cc: stable@kernel.org # 37.x
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Venkatesh Pallipadi <venki@google.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.hl>
Signed-off-by: NBorislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <1295534572-10730-1-git-send-email-bp@amd64.org>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

After changing the p2m mapping to a tree by

  commit 58e05027
    xen: convert p2m to a 3 level tree

and trying to boot a DomU with 615MB of memory, the following crash was
observed in the dump:

kernel direct mapping tables up to 26f00000 @ 1ec4000-1fff000
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<c0107397>] xen_set_pte+0x27/0x60
*pdpt = 0000000000000000 *pde = 0000000000000000

Adding further debug statements showed that when trying to set up
pfn=0x26700 the returned mapping was invalid.

pfn=0x266ff calling set_pte(0xc1fe77f8, 0x6b3003)
pfn=0x26700 calling set_pte(0xc1fe7800, 0x3)

Although the last_pfn obtained from the startup info is 0x26700, which
should in turn not be hit, the additional 8MB which are added as extra
memory normally seem to be ok. This lead to looking into the initial
p2m tree construction, which uses the smaller value and assuming that
there is other code handling the extra memory.

When the p2m tree is set up, the leaves are directly pointed to the
array which the domain builder set up. But if the mapping is not on a
boundary that fits into one p2m page, this will result in the last leaf
being only partially valid. And as the invalid entries are not
initialized in that case, things go badly wrong.

I am trying to fix that by checking whether the current leaf is a
complete map and if not, allocate a completely new page and copy only
the valid pointers there. This may not be the most efficient or elegant
solution, but at least it seems to allow me booting DomUs with memory
assignments all over the range.

BugLink: http://bugs.launchpad.net/bugs/686692
[v2: Redid a bit of commit wording and fixed a compile warning]
Signed-off-by: NStefan Bader <stefan.bader@canonical.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

In therm_throt.c, commit
9e76a97e patch doesn't export
the symbol platform_thermal_notify.

Other drivers (e.g. drivers/hwmon/coretemp.c) can not find the
symbol platform_thermal_notify when defining threshould
interrupt handler.

Please apply this patch to allow threshold interrupt handler in
coretemp.
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: R Durgadoss <durgadoss.r@intel.com>
Cc: khali@linux-fr.org <khali@linux-fr.org>
Cc: lm-sensors@lm-sensors.org <lm-sensors@lm-sensors.org>
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
LKML-Reference: <20110121041239.GB26954@linux-os.sc.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The implementation of the cache flushing interfaces on the x86
is identical with the default implementation in asm-generic.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: arnd@arndb.de
LKML-Reference: <1295523136-4277-2-git-send-email-akinobu.mita@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option
is used to configure any non-standard kernel with a much larger scope than
only small devices.

This patch renames the option to CONFIG_EXPERT in init/Kconfig and fixes
references to the option throughout the kernel.  A new CONFIG_EMBEDDED
option is added that automatically selects CONFIG_EXPERT when enabled and
can be used in the future to isolate options that should only be
considered for embedded systems (RISC architectures, SLOB, etc).

Calling the option "EXPERT" more accurately represents its intention: only
expert users who understand the impact of the configuration changes they
are making should enable it.
Reviewed-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NDavid Woodhouse <david.woodhouse@intel.com>
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Cc: Greg KH <gregkh@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Robin Holt <holt@sgi.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix sparse warning for non-ANSI function declaration:

arch/x86/xen/irq.c:129:30: warning: non-ANSI function declaration of function 'xen_init_irq_ops'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc:	Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

During early boot, local IRQ is disabled until IRQ subsystem is
properly initialized.  During this time, no one should enable
local IRQ and some operations which usually are not allowed with
IRQ disabled, e.g. operations which might sleep or require
communications with other processors, are allowed.

lockdep tracked this with early_boot_irqs_off/on() callbacks.
As other subsystems need this information too, move it to
init/main.c and make it generally available.  While at it,
toggle the boolean to early_boot_irqs_disabled instead of
enabled so that it can be initialized with %false and %true
indicates the exceptional condition.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NPekka Enberg <penberg@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <20110120110635.GB6036@htj.dyndns.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Update to latest definitions in:

   http://www.intel.com/Assets/PDF/appnote/241618.pdf

[ Note, this update of the doc has removed some old values which
  we have listed.  I think until we have clarification that they
  were never used in production, they should be left there. ]
Signed-off-by: NDave Jones <davej@redhat.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
LKML-Reference: <20110120012055.GA15985@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Honor the kconfig menu hierarchy to remove kconfig dependency warnings:
VIRTIO and VIRTIO_RING are subordinate to VIRTUALIZATION.

warning: (LGUEST_GUEST) selects VIRTIO which has unmet direct dependencies (VIRTUALIZATION)
warning: (LGUEST_GUEST && VIRTIO_PCI && VIRTIO_BALLOON) selects VIRTIO_RING which has unmet direct dependencies (VIRTUALIZATION && VIRTIO)
Reported-by: NToralf F_rster <toralf.foerster@gmx.de>
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

arch/x86/lguest/boot.c: In function ‘lguest_init_IRQ’:
arch/x86/lguest/boot.c:824: error: macro "__this_cpu_write" requires 2 arguments, but only 1 given
arch/x86/lguest/boot.c:824: error: ‘__this_cpu_write’ undeclared (first use in this function)
arch/x86/lguest/boot.c:824: error: (Each undeclared identifier is reported only once
arch/x86/lguest/boot.c:824: error: for each function it appears in.)

drivers/lguest/x86/core.c: In function ‘copy_in_guest_info’:
drivers/lguest/x86/core.c:94: error: lvalue required as left operand of assignment
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Use this_cpu_ops in a couple of places in lguest.
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

In order to be able to suppress the use of SRAT tables that
32-bit Linux can't deal with (in one case known to lead to a
non-bootable system, unless disabling ACPI altogether), move the
"numa=" option handling to common code.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Reviewed-by: NThomas Renninger <trenn@suse.de>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Renninger <trenn@suse.de>
LKML-Reference: <4D36B581020000780002D0FF@vpn.id2.novell.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This reverts commit 86b1e8dd ("x86: Make relocatable kernel work with
new binutils").

Markus Trippelsdorf reported a boot failure caused by this patch.

The real solution to the original patch will likely involve an
arch-generic solution to define an overlaid jiffies_64 and jiffies
variables.

Until that's done and tested on all architectures revert this commit to
solve the regression.
Reported-and-bisected-by: NMarkus Trippelsdorf <markus@trippelsdorf.de>
Acked-by: N"H. Peter Anvin" <hpa@zytor.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: "Lu, Hongjiu" <hongjiu.lu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Cc: Sam Ravnborg <sam@ravnborg.org>
LKML-Reference: <4D36A759.60704@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Mathias Merz reported that v2.6.37 failed to boot on his
system.

Make sure that the thread_info part of the irqstack is
initialized to zeroes.
Reported-and-Tested-by: NMatthias Merz <linux@merz-ka.de>
Signed-off-by: NBrian Gerst <brgerst@gmail.com>
Acked-by: NPekka Enberg <penberg@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <AANLkTimyKXfJ1x8tgwrr1hYnNLrPfgE1NTe4z7L6tUDm@mail.gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The CONFIG_RELOCATABLE=y option is broken with new binutils, which will make
boot panic.

According to Lu Hongjiu, the affected binutils are from 2.20.51.0.12 to
2.21.51.0.3, which are release since Oct 22 this year. At least ubuntu 10.10 is
using such binutils. See:

    http://sourceware.org/bugzilla/show_bug.cgi?id=12327

The reason of the boot panic is that we have 'jiffies = jiffies_64;' in
vmlinux.lds.S. The jiffies isn't in any section. In kernel build, there is
warning saying jiffies is an absolute address and can't be relocatable. At
runtime, jiffies will have virtual address 0.

Signed-off-by: Shaohua Li<shaohua.li@intel.com>
Cc: Lu Hongjiu<hongjiu.lu@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
LKML-Reference: <1295312269.1949.725.camel@sli10-conroe>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Fixes this build error:

 ERROR: "arbitrary_virt_to_machine" [drivers/xen/xen-gntdev.ko] undefined!
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>