Impact: reduce kernel BSS size by 7 pages, improve code readability

Two page tables are used in current x86_64 kexec implementation. One
is used to jump from kernel virtual address to identity map address,
the other is used to map all physical memory. In fact, on x86_64,
there is no conflict between kernel virtual address space and physical
memory space, so just one page table is sufficient. The page table
pages used to map control page are dynamically allocated to save
memory if kexec image is not loaded. ASM code used to map control page
is replaced by C code too.
Signed-off-by: NHuang Ying <ying.huang@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: make nmi_shootdown_cpus() callable from preemptible context

We need to know on which CPU we are running on, and we don't want to be
preempted while doing this.
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: widen nmi_shootdown_cpus() availability

The X86_LOCAL_APIC #ifdef was for kdump. For !SMP, the function simply
does nothing.
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: make nmi_shootdown_cpus() available to the rest of the x86 platform

Now nmi_shootdown_cpus() is ready to be used by non-kdump code also.
Move it to reboot.c.
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: make API available to the rest of x86 platform code

Add prototype to asm/reboot.h.
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: extend nmi_shootdown_cpus() with a callback

The reboot code will use a different function on crash_nmi_callback().
Adding a function pointer parameter to nmi_shootdown_cpus() for that.
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

For the kdump-specific code that was living on nmi_shootdown_cpus().
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

This variable will be moved to non-kdump-specific code.
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

The NMI CPU-halting code will be used on non-kdump cases, also
(e.g. emergency_reboot when virtualization is enabled).
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Turned off CONFIG_PCI_LEGACY and turned on EXT4, and otherwise mostly
took the defaults.  This also updates ppc6xx_defconfig, which covers
the 6xx/7xx/7xxx-based embedded boards.
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The new context may not be 16-byte aligned, so the real address of the
mcontext structure should be read from the uc_regs pointer instead of
directly using the (unaligned) uc_mcontext field.
Signed-off-by: NAndreas Schwab <schwab@suse.de>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

While investigating the failure of hibernation on 32-bit x86 with
CONFIG_NUMA set, as described in this message
http://marc.info/?l=linux-kernel&m=122634118116226&w=4
I asked some people for help and I was told that it wasn't really
worth the effort, because CONFIG_NUMA was generally broken on 32-bit
x86 systems and it shouldn't be used in such configs.  For this
reason, make CONFIG_NUMA depend on BROKEN instead of EXPERIMENTAL on
x86-32.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Pavel Machek <pavel@suse.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit 8dd94537.

This fixes a boot failure reported by Robert Reif.

The code above the section change expects to fallthrough, so
we can't make such a section change here.

Some functions that may be called from this handler require that
interrupts are disabled. Also, combining IRQF_DISABLED and
IRQF_SHARED does not reliably disable interrupts in a handler, so
remove IRQF_SHARED from the irq flags (this irq is not shared anyway).
Signed-off-by: NMatt Fleming <mjf@gentoo.org>
Cc: mingo@elte.hu
Cc: venkatesh.pallipadi@intel.com
Cc: "Will Newton" <will.newton@gmail.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

In hpet_next_event() we check that the value we just wrote to
HPET_Tn_CMP(timer) has reached the chip. Currently, we're checking that
the value we wrote to HPET_Tn_CMP(timer) is in HPET_T0_CMP, which, if
timer is anything other than timer 0, is likely to fail.
Signed-off-by: NMatt Fleming <mjf@gentoo.org>
Cc: mingo@elte.hu
Cc: venkatesh.pallipadi@intel.com
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

It is possible to flood the console with call traces if the WARN_ON
condition is true because of the frequency with which this function is
called.
Signed-off-by: NMatt Fleming <mjf@gentoo.org>
Cc: mingo@elte.hu
Cc: venkatesh.pallipadi@intel.com
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

unset CONFIG_PCI_LEGACY in the defconfigs as none of them enable
ISDN drivers which seem to be the only place we are using pci_find_device
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

Fixes following build error:

  CC      drivers/usb/gadget/fsl_qe_udc.o
drivers/usb/gadget/fsl_qe_udc.c: In function 'qe_eprx_stall_change':
drivers/usb/gadget/fsl_qe_udc.c:156: error: 'struct usb_ctlr' has no member named 'usb_usep'
drivers/usb/gadget/fsl_qe_udc.c:163: error: 'struct usb_ctlr' has no member named 'usb_usep'
drivers/usb/gadget/fsl_qe_udc.c: In function 'qe_eptx_stall_change':
drivers/usb/gadget/fsl_qe_udc.c:173: error: 'struct usb_ctlr' has no member named 'usb_usep'
drivers/usb/gadget/fsl_qe_udc.c:180: error: 'struct usb_ctlr' has no member named 'usb_usep'
drivers/usb/gadget/fsl_qe_udc.c: In function 'qe_eprx_nack':
drivers/usb/gadget/fsl_qe_udc.c:201: error: 'struct usb_ctlr' has no member named 'usb_usep'
drivers/usb/gadget/fsl_qe_udc.c:201: error: 'struct usb_ctlr' has no member named 'usb_usep'
drivers/usb/gadget/fsl_qe_udc.c: In function 'qe_eprx_normal':
drivers/usb/gadget/fsl_qe_udc.c:218: error: 'struct usb_ctlr' has no member named 'usb_usep'
drivers/usb/gadget/fsl_qe_udc.c:218: error: 'struct usb_ctlr' has no member named 'usb_usep'
drivers/usb/gadget/fsl_qe_udc.c: In function 'qe_ep_reset':
drivers/usb/gadget/fsl_qe_udc.c:325: error: 'struct usb_ctlr' has no member named 'usb_usep'
drivers/usb/gadget/fsl_qe_udc.c:342: error: 'struct usb_ctlr' has no member named 'usb_usep'
drivers/usb/gadget/fsl_qe_udc.c: In function 'qe_ep_register_init':
drivers/usb/gadget/fsl_qe_udc.c:515: error: 'struct usb_ctlr' has no member named 'usb_usep'
drivers/usb/gadget/fsl_qe_udc.c: In function 'ch9getstatus':
drivers/usb/gadget/fsl_qe_udc.c:1981: error: 'struct usb_ctlr' has no member named 'usb_usep'
make[2]: *** [drivers/usb/gadget/fsl_qe_udc.o] Error 1
Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

This patch corrects the bus-frequency value provided in the SBC610's dts.
Signed-off-by: NMartyn Welch <martyn.welch@gefanuc.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

The implemetation of _tlbil_pid() on Freescale Book-E cores needs
an msync & isync after we flash invalidate the TLBs.  This was causing
the following oops reported by Sebastian Andrzej Siewior:

  VFS: Mounted root (nfs filesystem) readonly.
  Freeing unused kernel memory: 148k init
  BUG: sleeping function called from invalid context at /home/bigeasy/git/linux-2.6-powerpc/mm/mmap.c:234
  in_atomic():1, irqs_disabled():0
  Call Trace:
  [df189df0] [c0007160] show_stack+0x48/0x148 (unreliable)
  [df189e30] [c0029480] __might_sleep+0xf0/0x100
  [df189e40] [c0070ac0] remove_vma+0x28/0x98
  [df189e50] [c0070c1c] exit_mmap+0xec/0x128
  [df189e80] [c002d2f4] mmput+0x54/0xec
  [df189ea0] [c0030b6c] exit_mm+0x10c/0x120
  [df189ed0] [c003288c] do_exit+0x1ac/0x6e8
  [df189f20] [c0032e48] do_group_exit+0x80/0xac
  [df189f40] [c000e9dc] ret_from_syscall+0x0/0x3c
  BUG: scheduling while atomic: udevd/956/0x10000002
  Modules linked in:
  Call Trace:
  [df189df0] [c0007160] show_stack+0x48/0x148 (unreliable)
  [df189e30] [c002ac88] __schedule_bug+0x58/0x6c
  [df189e40] [c023e6cc] schedule+0xa8/0x4a8
  [df189e90] [c002ad6c] __cond_resched+0x38/0x64
  [df189ea0] [c023ebc8] _cond_resched+0x3c/0x58
  [df189eb0] [c0030e70] put_files_struct+0x90/0xec
  [df189ed0] [c00328a8] do_exit+0x1c8/0x6e8
  [df189f20] [c0032e48] do_group_exit+0x80/0xac
  [df189f40] [c000e9dc] ret_from_syscall+0x0/0x3c
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

sched_clock() uses cycles_2_ns() needlessly - which is an irq-disabling
variant of __cycles_2_ns().

Most of the time sched_clock() is called with irqs disabled already.
The few places that call it with irqs enabled need to be updated.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

in scheduler-intense workloads native_read_tsc() overhead accounts for
20% of the system overhead:

 659567 system_call                              41222.9375
 686796 schedule                                 435.7843
 718382 __switch_to                              665.1685
 823875 switch_mm                                4526.7857
 1883122 native_read_tsc                          55385.9412
 9761990 total                                      2.8468

this is large part due to the rdtsc_barrier() that is done before
and after reading the TSC.

But sched_clock() is not a precise clock in the GTOD sense, using such
barriers is completely pointless. So remove the barriers and only use
them in vget_cycles().

This improves lat_ctx performance by about 5%.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

IA64 kdump kernel failed to initialize /proc/vmcore in 2.6.28-rc2.
A bug was introduced in this patch commit:

  d9a9855d
  always reserve elfcore header memory in crash kernel

The problem was that the call to reserve_elfcorehdr() should be placed
in CONFIG_CRASH_DUMP rather than in CONFIG_CRASH_KERNEL, which does
not exist.
Signed-off-by: NJay Lan <jlan@sgi.com>
Acked-by: NSimon Hormon <horms@verge.net.au>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Fix the counter overflow check for CPUs with counter width > 32

I had a similar change in a different patch that I didn't submit
and I didn't notice the problem earlier because it was always
tested together.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NRobert Richter <robert.richter@amd.com>

Xen requires that all mappings of pagetable pages are read-only, so
that they can't be updated illegally.  As a result, if a page is being
turned into a pagetable page, we need to make sure all its mappings
are RO.

If the page had been used for ioremap or vmalloc, it may still have
left over mappings as a result of not having been lazily unmapped.
This change makes sure we explicitly mop them all up before pinning
the page.

Unlike aliases created by kmap, the there can be vmalloc aliases even
for non-high pages, so we must do the flush unconditionally.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Linux Memory Management List <linux-mm@kvack.org>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fix 32-bit Xen guest boot crash

On 32-bit PAE, pud_page, for no good reason, didn't really return a
struct page *.  Since Jan Beulich's fix "i386/PAE: fix pud_page()",
pud_page does return a struct page *.

Because PAE has 3 pagetable levels, the pud level is folded into the
pgd level, so pgd_page() is the same as pud_page(), and now returns
a struct page *.  Update the xen/mmu.c code which uses pgd_page()
accordingly.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

When 'start' and 'end' are less than a cacheline apart and 'start' is
unaligned we are done after cleaning and invalidating the first
cacheline.  So check for (start < end) which will not walk off into
invalid address ranges when (start > end).

This issue was caught by drivers/dma/dmatest.

2.6.27 is susceptible.

Cc: <stable@kernel.org>
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Lothar WaÃ<9f>mann <LW@KARO-electronics.de>
Cc: Lennert Buytenhek <buytenh@marvell.com>
Cc: Eric Miao <eric.miao@marvell.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

As a result of the ptebits changes, we ended up marking device mappings
as normal memory on ARMv7 CPUs, resulting in undesirable behaviour with
serial ports and the like.  While reviewing the section mapping table
entries, other errors in the memory type settings for devices were
detected and confirmed to prevent Xscale3 platforms booting.

Tested on:
	OMAP34xx (ARMv7),
	OMAP24xx (ARMv6),
	OMAP16xx (ARM926T, ARMv5),
	PXA311 (Xscale3),
	PXA272 (Xscale),
	PXA255 (Xscale),
	IXP42x (Xscale),
	S3C2410 (ARM920T, ARMv4T),
	ARM720T (ARMv4T)
	StrongARM-110 (ARMv4)
Acked-by: NTony Lindgren <tony@atomide.com>
Tested-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Tested-by: NMike Rapoport <mike@compulab.co.il>
Tested-by: NBen Dooks <ben-linux@fluff.org>
Tested-by: NAnders Grafström <grfstrm@users.sourceforge.net>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This fixes a regression introduced by 2c6e6db4
"Minimize per_cpu reservations."  That patch incorrectly used information about
what CPUs are possible that was not yet initialized by ACPI.  The end result
was that per_cpu structures for offline CPUs were not initialized causing a
NULL pointer reference.

Since we cannot do the full acpi_boot_init() call any earlier, the simplest
fix is to just parse the MADT for SAPIC entries early to find the CPU
info.  This should also allow for some cleanup of the code added by the
"Minimize per_cpu reservations".  This patch just fixes the regressions, the
cleanup will come in a later patch.
Signed-off-by: NDoug Chapman <doug.chapman@hp.com>
Signed-off-by: NAlex Chiang <achiang@hp.com>
CC: Robin Holt <holt@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

No functional change, just reorder some config options and update
the "Power management and ACPI" label to match the defacto x86
standard.
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

As of 73bdf0a6, the kernel needs
to know where modules are located in the virtual address space.
On ARM, we located this region between MODULE_START and MODULE_END.
Unfortunately, everyone else calls it MODULES_VADDR and MODULES_END.
Update ARM to use the same naming, so is_vmalloc_or_module_addr()
can work properly.  Also update the comment on mm/vmalloc.c to
reflect that ARM also places modules in a separate region from the
vmalloc space.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This reverts commit c7ffa6c2.

the assumptio of this change was that this would not break
any existing machine. Andrey Borzenkov reported troubles with
the ACPI reboot method: the system would hang on reboot, necessiating
a power cycle. Probably more systems are affected as well.

Also, there are patches queued up for v2.6.29 to disable virtualization
on emergency_restart() - which was the original motivation of
this change.
Reported-by: NAndrey Borzenkov <arvidjaar@mail.ru>
Bisected-by: NAndrey Borzenkov <arvidjaar@mail.ru>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Acked-by: NAvi Kivity <avi@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: right-align /proc/meminfo consistent with other fields

When the split-LRU patches added Inactive(anon) and Inactive(file) lines
to /proc/meminfo, all counts were moved two columns rightwards to fit in.
Now move x86's DirectMap lines two columns rightwards to line up.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Lazy flushing needs to take care of the unmap path too which is not yet
implemented and leads to stale IO/TLB entries. This is fixed by this
patch.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Impact: fix rare x2apic hang

On x86, x2apic mode accesses for sending IPI's don't have serializing
semantics. If the IPI receivner refers(in lock-free fashion) to some
memory setup by the sender, the need for smp_mb() before sending the
IPI becomes critical in x2apic mode.

Add the smp_mb() in native_flush_tlb_others() before sending the IPI.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fix warning message when PARAVIRT is set in config

Remove stale #ifdef components from our IRQ sizing logic.
x86/Voyager is the only holdout.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: clarify menuconfig text

Mention ACPI in the top-level menu to give a clue as to where
it lives. This matches what ia64 does.
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: make NR_IRQS big enough for system with lots of apic/pins

If lots of IO_APIC's are there (or can be there), size the same way
as 64-bit, depending on MAX_IO_APICS and NR_CPUS.

This fixes the boot problem reported by Ben Hutchings on a 32-bit
server with 5 IO-APICs and 240 IO-APIC pins.
Signed-off-by: NYinghai <yinghai@kernel.org>
Tested-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fix boot hang on 32-bit systems with more than 224 IO-APIC pins

On some 32-bit systems with a lot of IO-APICs probe_nr_irqs() can
return a value larger than NR_IRQS. This will lead to probe_irq_on()
overrunning the irq_desc array.

I hit this when running net-next-2.6 (close to 2.6.28-rc3) on a
Supermicro dual Xeon system.  NR_IRQS is 224 but probe_nr_irqs() detects
5 IOAPICs and returns 240.  Here are the log messages:

Tue Nov  4 16:53:47 2008 ACPI: IOAPIC (id[0x01] address[0xfec00000] gsi_base[0])
Tue Nov  4 16:53:47 2008 IOAPIC[0]: apic_id 1, version 32, address 0xfec00000, GSI 0-23
Tue Nov  4 16:53:47 2008 ACPI: IOAPIC (id[0x02] address[0xfec81000] gsi_base[24])
Tue Nov  4 16:53:47 2008 IOAPIC[1]: apic_id 2, version 32, address 0xfec81000, GSI 24-47
Tue Nov  4 16:53:47 2008 ACPI: IOAPIC (id[0x03] address[0xfec81400] gsi_base[48])
Tue Nov  4 16:53:47 2008 IOAPIC[2]: apic_id 3, version 32, address 0xfec81400, GSI 48-71
Tue Nov  4 16:53:47 2008 ACPI: IOAPIC (id[0x04] address[0xfec82000] gsi_base[72])
Tue Nov  4 16:53:47 2008 IOAPIC[3]: apic_id 4, version 32, address 0xfec82000, GSI 72-95
Tue Nov  4 16:53:47 2008 ACPI: IOAPIC (id[0x05] address[0xfec82400] gsi_base[96])
Tue Nov  4 16:53:47 2008 IOAPIC[4]: apic_id 5, version 32, address 0xfec82400, GSI 96-119
Tue Nov  4 16:53:47 2008 ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 high edge)
Tue Nov  4 16:53:47 2008 ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level)
Tue Nov  4 16:53:47 2008 Enabling APIC mode:  Flat.  Using 5 I/O APICs
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Acked-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>