Make sure that irq_enter()/irq_exit() wrap the entire event processing
loop, rather than each individual event invokation.  This makes sure
that softirq processing is deferred until the end of event processing,
rather than in the middle with interrupts disabled.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

There should be no need for us to maintain our own bind count for
irqs, since the surrounding irq system should keep track of shared
irqs for us.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Put all irq info into one struct.  Also, use a union to keep
event channel type-specific information, rather than overloading the
index field.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Rather than overloading vectors for event channels, take full
responsibility for mapping an event channel to irq directly.  With
this patch Xen has its own irq allocator.

When the kernel gets an event channel upcall, it maps the event
channel number to an irq and injects it into the normal interrupt
path.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Conflicts:
	arch/x86/mach-voyager/voyager_smp.c

By default, the irq_chip.disable operation is a no-op.  Explicitly set
it to disable the Xen event channel.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

With the differences in interrupt handling hoisted into handle_irq(),
do_IRQ is more or less identical between 32 and 64 bit, so unify it.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Xen uses a different interrupt path, so introduce handle_irq() to
allow interrupts to be inserted into the normal interrupt path.  This
is handled slightly differently on 32 and 64-bit.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: find right nr_irqs_gsi on some systems.

One test-system has gap between gsi's:

[    0.000000] ACPI: IOAPIC (id[0x04] address[0xfec00000] gsi_base[0])
[    0.000000] IOAPIC[0]: apic_id 4, version 0, address 0xfec00000, GSI 0-23
[    0.000000] ACPI: IOAPIC (id[0x05] address[0xfeafd000] gsi_base[48])
[    0.000000] IOAPIC[1]: apic_id 5, version 0, address 0xfeafd000, GSI 48-54
[    0.000000] ACPI: IOAPIC (id[0x06] address[0xfeafc000] gsi_base[56])
[    0.000000] IOAPIC[2]: apic_id 6, version 0, address 0xfeafc000, GSI 56-62
...
[    0.000000] nr_irqs_gsi: 38

So nr_irqs_gsi is not right. some irq for MSI will overwrite with io_apic.

need to get that with acpi_probe_gsi when acpi io_apic is used
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: make check-timer more robust potentially solve boot fragility

For edge trigger io-apic routing, we already unmasked the pin via
setup_IO_APIC_irq(), so don't unmask it again.

Also call local_irq_disable() between timer_irq_works(), because it
calls local_irq_enable() inside.

Also remove not needed apic version reading for 64-bit
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

also could kill platform_legacy_irq
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: make nr_irqs depend more on cards used in a system

depend on nr_irq_gsi more, and have a ratio for MSI.

v2: make nr_irqs less than NR_VECTORS * nr_cpu_ids
    aka if only one cpu, we only can support nr_irqs = NR_VECTORS
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

- Consistent alignment of help text
- Use the ---help--- keyword everywhere consistently as a visual separator
- fix whitespace mismatches
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Also move xquad_portio over to where it's allocated.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Conflicts:
	arch/x86/mach-default/setup.c

Semantic merge:
	arch/x86/kernel/irqinit_32.c
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This function should be provided on UP too.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

only leave _default_ipi_xx etc in .h

Beyond the cleanup factor, this saves a bit of code size as well:

    text	   data	    bss	    dec	            hex	filename
 7281931	1630144	1463304	10375379	 9e50d3	vmlinux.before
 7281753	1630144	1463304	10375201	 9e5021	vmlinux.after
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

disable_ioapic_setup() in init/main.c is ugly as the function is
x86-specific. The #ifdef inline prototype there is ugly too.

Replace it with a generic arch_disable_smp_support() function - which
has a weak alias for non-x86 architectures and for non-ioapic x86 builds.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Due to recurring issues with DMAR support on certain platforms.
There's a number of filesystem corruption incidents reported:

  https://bugzilla.redhat.com/show_bug.cgi?id=479996
  http://bugzilla.kernel.org/show_bug.cgi?id=12578

Provide a Kconfig option to change whether it is enabled by
default.

If disabled, it can still be reenabled by passing intel_iommu=on to the
kernel. Keep the .config option off by default.
Signed-off-by: NKyle McMartin <kyle@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-By: NDavid Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

On an x86 system which doesn't support global mappings,
__supported_pte_mask has _PAGE_GLOBAL clear, to make sure it never
appears in the PTE.  pfn_pte() and so on will enforce it with:

static inline pte_t pfn_pte(unsigned long page_nr, pgprot_t pgprot)
{
	return __pte((((phys_addr_t)page_nr << PAGE_SHIFT) |
		      pgprot_val(pgprot)) & __supported_pte_mask);
}

However, we overload _PAGE_GLOBAL with _PAGE_PROTNONE on non-present
ptes to distinguish them from swap entries.  However, applying
__supported_pte_mask indiscriminately will clear the bit and corrupt the
pte.

I guess the best fix is to only apply __supported_pte_mask to present
ptes.  This seems like the right solution to me, as it means we can
completely ignore the issue of overlaps between the present pte bits and
the non-present pte-as-swap entry use of the bits.

__supported_pte_mask contains the set of flags we support on the
current hardware.  We also use bits in the pte for things like
logically present ptes with no permissions, and swap entries for
swapped out pages.  We should only apply __supported_pte_mask to
present ptes, because otherwise we may destroy other information being
stored in the ptes.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Enable the use of the direct vcpu-access operations on 64-bit.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Now that x86-64 has directly accessible percpu variables, it can also
implement the direct versions of these operations, which operate on a
vcpu_info structure directly embedded in the percpu area.

In fact, the 64-bit versions are more or less identical, and so can be
shared.  The only two differences are:
 1. xen_restore_fl_direct takes its argument in eax on 32-bit, and rdi on 64-bit.
    Unfortunately it isn't possible to directly refer to the 2nd lsb of rdi directly
    (as you can with %ah), so the code isn't quite as dense.
 2. check_events needs to variants to save different registers.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

We need to access percpu data fairly early, so set up the percpu
registers as soon as possible.  We only need to load the appropriate
segment register.  We already have a GDT, but its hard to change it
early because we need to manipulate the pagetable to do so, and that
hasn't been set up yet.

Also, set the kernel stack when bringing up secondary CPUs.  If we
don't they all end up sharing the same stack...
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Moving the mmu code from enlighten.c to mmu.c inadvertently broke the
32-bit build.  Fix it.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Fix user-visible grammo.
Signed-off-by: NAlex Chiang <achiang@hp.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

Some lines exceed the 80 char width making them unreadable.
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch echoes what we already do on 32-bit since
90f7d25c, and prints the DMI
product name in show_regs, so that system specific problems can be
easily identified.
Signed-off-by: NKyle McMartin <kyle@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fix to enable APIC for AMD Fam10h on chipsets with a missing/b0rked
	ACPI MP table (MADT)

Booting a 32bit kernel on an AMD Fam10h CPU running on chipsets with
missing/b0rked MP table leads to a hang pretty early in the boot process
due to the APIC not being initialized. Fix that by falling back to the
default APIC base address in 32bit code, as it is done in the 64bit
codepath.
Signed-off-by: NBorislav Petkov <borislav.petkov@amd.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: Fix race condition

xen_mc_batch has a small preempt race where it takes the address of a
percpu variable immediately before disabling interrupts, thereby
leaving a small window in which we may migrate to another cpu and save
the flags in the wrong percpu variable.  Disable interrupts before
saving the old flags in a percpu.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: Bug fix

A hunk went missing in the original patch, and callee-save callsites were
not marked as returning the upper 32-bit of result, causing Badness.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: Documentation only

There is an email alias as well to reach the x86 maintainers: x86@kernel.org.
Document it.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: Fixes dumpstack and KDB on 64 bits

This re-adds the old stack pointer to the top of the irqstack to help
with unwinding.  It was removed in commit d99015b1
as part of the save_args out-of-line work.

Both dumpstack and KDB require this information.
Signed-off-by: NMartin Hicks <mort@sgi.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: fix regression with kexec with vmlinux

Split data.init into data.init, percpu, data.init2 sections
instead of let data.init wrap percpu secion.

Thus kexec loading will be happy, because sections will not
overlap.

Before the patch we have:

Elf file type is EXEC (Executable file)
Entry point 0x200000
There are 6 program headers, starting at offset 64

Program Headers:
  Type           Offset             VirtAddr           PhysAddr
                 FileSiz            MemSiz              Flags  Align
  LOAD           0x0000000000200000 0xffffffff80200000 0x0000000000200000
                 0x0000000000ca6000 0x0000000000ca6000  R E    200000
  LOAD           0x0000000000ea6000 0xffffffff80ea6000 0x0000000000ea6000
                 0x000000000014dfe0 0x000000000014dfe0  RWE    200000
  LOAD           0x0000000001000000 0xffffffffff600000 0x0000000000ff4000
                 0x0000000000000888 0x0000000000000888  RWE    200000
  LOAD           0x00000000011f6000 0xffffffff80ff6000 0x0000000000ff6000
                 0x0000000000073086 0x0000000000a2d938  RWE    200000
  LOAD           0x0000000001400000 0x0000000000000000 0x000000000106a000
                 0x00000000001d2ce0 0x00000000001d2ce0  RWE    200000
  NOTE           0x00000000009e2c1c 0xffffffff809e2c1c 0x00000000009e2c1c
                 0x0000000000000024 0x0000000000000024         4

 Section to Segment mapping:
  Segment Sections...
   00     .text .notes __ex_table .rodata __bug_table .pci_fixup .builtin_fw __ksymtab __ksymtab_gpl __ksymtab_strings __init_rodata __param
   01     .data .init.rodata .data.cacheline_aligned .data.read_mostly
   02     .vsyscall_0 .vsyscall_fn .vsyscall_gtod_data .vsyscall_1 .vsyscall_2 .vgetcpu_mode .jiffies
   03     .data.init_task .smp_locks .init.text .init.data .init.setup .initcall.init .con_initcall.init .x86_cpu_dev.init .altinstructions .altinstr_replacement .exit.text .init.ramfs .bss
   04     .data.percpu
   05     .notes

After patch we've got:

Elf file type is EXEC (Executable file)
Entry point 0x200000
There are 7 program headers, starting at offset 64

Program Headers:
  Type           Offset             VirtAddr           PhysAddr
                 FileSiz            MemSiz              Flags  Align
  LOAD           0x0000000000200000 0xffffffff80200000 0x0000000000200000
                 0x0000000000ca6000 0x0000000000ca6000  R E    200000
  LOAD           0x0000000000ea6000 0xffffffff80ea6000 0x0000000000ea6000
                 0x000000000014dfe0 0x000000000014dfe0  RWE    200000
  LOAD           0x0000000001000000 0xffffffffff600000 0x0000000000ff4000
                 0x0000000000000888 0x0000000000000888  RWE    200000
  LOAD           0x00000000011f6000 0xffffffff80ff6000 0x0000000000ff6000
                 0x0000000000073086 0x0000000000073086  RWE    200000
  LOAD           0x0000000001400000 0x0000000000000000 0x000000000106a000
                 0x00000000001d2ce0 0x00000000001d2ce0  RWE    200000
  LOAD           0x000000000163d000 0xffffffff8123d000 0x000000000123d000
                 0x0000000000000000 0x00000000007e6938  RWE    200000
  NOTE           0x00000000009e2c1c 0xffffffff809e2c1c 0x00000000009e2c1c
                 0x0000000000000024 0x0000000000000024         4

 Section to Segment mapping:
  Segment Sections...
   00     .text .notes __ex_table .rodata __bug_table .pci_fixup .builtin_fw __ksymtab __ksymtab_gpl __ksymtab_strings __init_rodata __param
   01     .data .init.rodata .data.cacheline_aligned .data.read_mostly
   02     .vsyscall_0 .vsyscall_fn .vsyscall_gtod_data .vsyscall_1 .vsyscall_2 .vgetcpu_mode .jiffies
   03     .data.init_task .smp_locks .init.text .init.data .init.setup .initcall.init .con_initcall.init .x86_cpu_dev.init .altinstructions .altinstr_replacement .exit.text .init.ramfs
   04     .data.percpu
   05     .bss
   06     .notes
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI hotplug: Change link order of pciehp & acpiphp
  PCI hotplug: fakephp: Allocate PCI resources before adding the device
  PCI MSI: Fix undefined shift by 32
  PCI PM: Do not wait for buses in B2 or B3 during resume
  PCI PM: Power up devices before restoring their state
  PCI PM: Fix hibernation breakage on EeePC 701
  PCI: irq and pci_ids patch for Intel Tigerpoint DeviceIDs
  PCI PM: Fix suspend error paths and testing facility breakage

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
  slub: fix per cpu kmem_cache_cpu array memory leak
  kmalloc: return NULL instead of link failure

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  fbdev/atyfb: Fix DSP config on some PowerMacs & PowerBooks
  powerpc: Fix oops on some machines due to incorrect pr_debug()
  powerpc/ps3: Printing fixups for l64 to ll64 convserion drivers/net
  powerpc/5200: update device tree binding documentation
  powerpc/5200: Bugfix for PCI mapping of memory and IMMR
  powerpc/5200: update defconfigs

Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched_rt: don't use first_cpu on cpumask created with cpumask_and
  sched: fix buddie group latency
  sched: clear buddies more aggressively
  sched: symmetric sync vs avg_overlap
  sched: fix sync wakeups
  cpuset: fix possible deadlock in async_rebuild_sched_domains