Impact: crash fix

head_32.S needs to map the kernel itself, and enough space so
that mm/init.c can allocate space from the e820 allocator
for the linear map of low memory.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Impact: makes vmlinux section information more useful

Don't use ram after _end blindly for pagetables. aka init pages is before _end
put those pg table into .bss

[Adapted to use brk segment - Jeremy]

v2: keep initial page table up to 512M only.
v4: put initial page tables just before _end
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: new interface; remove hard-coded limit

Add RESERVE_BRK(name, size) macro to reserve space in the brk
area.  This should be a conservative (ie, larger) estimate of
how much space might possibly be required from the brk area.
Any unused space will be freed, so there's no real downside
on making the reservation too large (within limits).

The name should be unique within a given file, and somewhat
descriptive.

The C definition of RESERVE_BRK() ends up being more complex than
one would expect to work around a cluster of gcc infelicities:

  The first attempt was to simply try putting __section(.brk_reservation)
  on a variable.  This doesn't work because it ends up making it a
  @progbits section, which gets actual space allocated in the vmlinux
  executable.

  The second attempt was to emit the space into a section using asm,
  but gcc doesn't allow arguments to be passed to file-level asm()
  statements, making it hard to pass in the size.

  The final attempt is to wrap the asm() in a function to allow
  it to have arguments, and put the function itself into the
  .discard section, which vmlinux*.lds drops entirely from the
  emitted vmlinux.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: simplification

We only need to map the kernel in head_32.S, not the whole of
lowmem.  We use 512MB as a reasonable (but arbitrary) limit on
the maximum size of the kernel image.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: use new interface instead of previous ad hoc implementation

Use extend_brk() to allocate memory for DMI rather than having an
ad-hoc allocator.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: use new interface instead of previous ad hoc implementation

Rather than having special purpose init_pg_table_start/end variables
to delimit the kernel pagetable built by head_32.S, just use the brk
mechanism to extend the bss for the new pagetable.

This patch removes init_pg_table_start/end and pg0, defines __brk_base
(which is page-aligned and immediately follows _end), initializes
the brk region to start there, and uses it for the 32-bit pagetable.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: build fix

The brk initialization functions were incorrectly located inside
an #ifdef CONFIG_VLK_DEV_INITRD block, causing the obvious build failure in
minimal configurations.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

Impact: new interface

Add a brk()-like allocator which effectively extends the bss in order
to allow very early code to do dynamic allocations.  This is better than
using statically allocated arrays for data in subsystems which may never
get used.

The space for brk allocations is in the bss ELF segment, so that the
space is mapped properly by the code which maps the kernel, and so
that bootloaders keep the space free rather than putting a ramdisk or
something into it.

The bss itself, delimited by __bss_stop, ends before the brk area
(__brk_base to __brk_limit).  The kernel text, data and bss is reserved
up to __bss_stop.

Any brk-allocated data is reserved separately just before the kernel
pagetable is built, as that code allocates from unreserved spaces
in the e820 map, potentially allocating from any unused brk memory.
Ultimately any unused memory in the brk area is used in the general
kernel memory pool.

Initially the brk space is set to 1MB, which is probably much larger
than any user needs (the largest current user is i386 head_32.S's code
to build the pagetables to map the kernel, which can get fairly large
with a big kernel image and no PSE support).  So long as the system
has sufficient memory for the bootloader to reserve the kernel+1MB brk,
there are no bad effects resulting from an over-large brk.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: cleanup

Move the symbols delimiting a section part of the section
(section relative) rather than absolute.  This avoids any
unexpected gaps between the section-start symbol and the first
data in the section, which could be caused by implicit
alignment of the section data.  It also makes the general
form of vmlinux_64.lds.S consistent with vmlinux_32.lds.S.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

move store_ldt outside the CONFIG_PARAVIRT section and
also clean up the code a bit.
Signed-off-by: NJaswinder Singh Rajput <jaswinder@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

Convert the last remaining users.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Impact: saving power _very_ little

round_jiffies() round up absolute jiffies to full second.
round_jiffies_relative() round up relative jiffies to full second.

The "t->expires" is absolute jiffies. Then, round_jiffies() should be
used instead round_jiffies_relative().
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: New major feature

This patch add kexec jump support for x86_64. More information about
kexec jump can be found in corresponding x86_32 support patch.
Signed-off-by: NHuang Ying <ying.huang@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: Fix corner case that cannot yet occur

image->start may be outside of 0 ~ max_pfn, for example when jumping
back to original kernel from kexeced kenrel. This patch add identity
map for pages at image->start.
Signed-off-by: NHuang Ying <ying.huang@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: Cleanup

Fix some coding style issue for kexec x86.
Signed-off-by: NHuang Ying <ying.huang@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Introduce:

 cat /sys/kernel/debug/x86/cpu/*

for Intel and AMD processors to view / debug the state of each CPU.

By using this we can debug whole range of registers and other
cpu information for debugging purpose and monitor how things
are changing.

This can be useful for developers as well as for users.
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>
LKML-Reference: <1236701373.3387.4.camel@localhost.localdomain>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup
Signed-off-by: NStoyan Gaydarov <stoyboyker@gmail.com>
LKML-Reference: <1236661850-8237-8-git-send-email-stoyboyker@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: code reorganization

Separate out embedding first chunk setup helper from x86 embedding
first chunk allocator and put it in mm/percpu.c.  This will be used by
the default percpu first chunk allocator and possibly by other archs.
Signed-off-by: NTejun Heo <tj@kernel.org>

Impact: cleanup, more flexibility for first chunk init

Non-negative @dyn_size used to be allowed iff @unit_size wasn't auto.
This restriction stemmed from implementation detail and made things a
bit less intuitive.  This patch allows @dyn_size to be specified
regardless of @unit_size and swaps the positions of @dyn_size and
@unit_size so that the parameter order makes more sense (static,
reserved and dyn sizes followed by enclosing unit_size).

While at it, add @unit_size >= PCPU_MIN_UNIT_SIZE sanity check.
Signed-off-by: NTejun Heo <tj@kernel.org>

This reverts commit e088e4c9.

Removing the sysfs interface for p4-clockmod was flagged as a
regression in bug 12826.

Course of action:
 - Find out the remaining causes of overheating, and fix them
   if possible. ACPI should be doing the right thing automatically.
   If it isn't, we need to fix that.
 - mark p4-clockmod ui as deprecated
 - try again with the removal in six months.

It's not really feasible to printk about the deprecation, because
it needs to happen at all the sysfs entry points, which means adding
a lot of strcmp("p4-clockmod".. calls to the core, which.. bleuch.
Signed-off-by: NDave Jones <davej@redhat.com>

Impact: cleanup and code size reduction on 64-bit

This code is only applied to Intel Pentium and AMD K7 32-bit cpus.

Move those checks to intel_init()/amd_init() for 32-bit
so 64-bit will not build this code.

Also change to use cpu_index check to see if we need to emit warning.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <49B377D2.8030108@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In uv_flush_tlb_others() (arch/x86/kernel/tlb_uv.c),
the "WARN_ON(!in_atomic())" fails if CONFIG_PREEMPT is not enabled.

And CONFIG_PREEMPT is not enabled by default in the distribution that
most UV owners will use.

We could #ifdef CONFIG_PREEMPT the warning, but that is not good form.
And there seems to be no suitable fix to in_atomic() when CONFIG_PREMPT
is not on.

As Ingo commented:

  > and we have no proper primitive to test for atomicity. (mainly
  > because we dont know about atomicity on a non-preempt kernel)

So we drop the WARN_ON.
Signed-off-by: NCliff Wickman <cpw@sgi.com>
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

ds_write_config() can write the BTS as well as the PEBS part of
the DS config. ds_request_pebs() passes the wrong qualifier, which
results in the wrong configuration to be written.
Reported-by: NStephane Eranian <eranian@googlemail.com>
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
LKML-Reference: <20090305085721.A22550@sedona.ch.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In case a ptraced task is reaped (while the tracer is still attached),
ds_exit_thread() is called before ptrace_exit(). The latter will
release the bts_tracer and remove the thread's ds_ctx.
The former will WARN() if the context is not NULL.

Oleg Nesterov submitted patches that move ptrace_exit() before
exit_thread() and thus reverse the order of the above calls.

Remove the bad warning. I will add it again when Oleg's changes are in.
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
LKML-Reference: <20090305084954.A22000@sedona.ch.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fix relocation overflow during module load

x86_64 uses 32bit relocations for symbol access and static percpu
symbols whether in core or modules must be inside 2GB of the percpu
segement base which the dynamic percpu allocator doesn't guarantee.
This patch makes x86_64 reserve PERCPU_MODULE_RESERVE bytes in the
first chunk so that module percpu areas are always allocated from the
first chunk which is always inside the relocatable range.

This problem exists for any percpu allocator but is easily triggered
when using the embedding allocator because the second chunk is located
beyond 2GB on it.

This patch also changes the meaning of PERCPU_DYNAMIC_RESERVE such
that it only indicates the size of the area to reserve for dynamic
allocation as static and dynamic areas can be separate.  New
PERCPU_DYNAMIC_RESERVED is increased by 4k for both 32 and 64bits as
the reserved area separation eats away some allocatable space and
having slightly more headroom (currently between 4 and 8k after
minimal boot sans module area) makes sense for common case
performance.

x86_32 can address anywhere from anywhere and doesn't need reserving.

Mike Galbraith first reported the problem first and bisected it to the
embedding percpu allocator commit.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NMike Galbraith <efault@gmx.de>
Reported-by: NJaswinder Singh Rajput <jaswinder@kernel.org>

Impact: add reserved allocation functionality and use it for module
	percpu variables

This patch implements reserved allocation from the first chunk.  When
setting up the first chunk, arch can ask to set aside certain number
of bytes right after the core static area which is available only
through a separate reserved allocator.  This will be used primarily
for module static percpu variables on architectures with limited
relocation range to ensure that the module perpcu symbols are inside
the relocatable range.

If reserved area is requested, the first chunk becomes reserved and
isn't available for regular allocation.  If the first chunk also
includes piggy-back dynamic allocation area, a separate chunk mapping
the same region is created to serve dynamic allocation.  The first one
is called static first chunk and the second dynamic first chunk.
Although they share the page map, their different area map
initializations guarantee they serve disjoint areas according to their
purposes.

If arch doesn't setup reserved area, reserved allocation is handled
like any other allocation.
Signed-off-by: NTejun Heo <tj@kernel.org>

Impact: reduce unnecessary memory usage on certain configurations

Embedding percpu allocator allocates unit_size *
smp_num_possible_cpus() bytes consecutively and use it for the first
chunk.  However, if the static area is small, this can result in
excessive prellocated free space in the first chunk due to
PCPU_MIN_UNIT_SIZE restriction.

This patch makes embedding percpu allocator preallocate only what's
necessary as described by PERPCU_DYNAMIC_RESERVE and return the
leftover to the bootmem allocator.
Signed-off-by: NTejun Heo <tj@kernel.org>

Impact: argument semantic cleanup

In pcpu_setup_first_chunk(), zero @unit_size and @dyn_size meant
auto-sizing.  It's okay for @unit_size as 0 doesn't make sense but 0
dynamic reserve size is valid.  Alos, if arch @dyn_size is calculated
from other parameters, it might end up passing in 0 @dyn_size and
malfunction when the size is automatically adjusted.

This patch makes both @unit_size and @dyn_size ssize_t and use -1 for
auto sizing.
Signed-off-by: NTejun Heo <tj@kernel.org>

Impact: cleanup, micro-optimization

Pre-initialize boot_cpu_data.x86_phys_bits to a reasonable default
to remove the use of system_state tests in __virt_addr_valid()
and __phys_addr().
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Fix non-smp build of uv_time.c.
Signed-off-by: NDimitri Sivanich <sivanich@sgi.com>
LKML-Reference: <20090304220246.GC6288@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Dell XPS710 will hang on reboot.  This is resolved by adding a quirk to
set bios reboot.
Signed-off-by: NLeann Ogasawara <leann.ogasawara@canonical.com>
Signed-off-by: NTim Gardner <tim.gardner@canonical.com>
Cc: "manoj.iyer" <manoj.iyer@canonical.com>
Cc: <stable@kernel.org>
LKML-Reference: <1236196380.3231.89.camel@emiko>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: save a bit of RAM

Get the exact size for the reserve_bootmem() call.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <49AE4922.605@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fix boot with mptable above max_low_mapped

Try to use early_ioremap() to map MPC to make sure it works even it is
at the end of ram.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <49AE4901.3090801@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Reported-and-tested-by: NKevin O'Connor <kevin@koconnor.net>

Impact: fix math-emu related crash while using GDB/ptrace

init_fpu() calls finit to initialize a task's xstate, while finit always
works on the current task. If we use PTRACE_GETFPREGS on another
process and both processes did not already use floating point, we get
a null pointer exception in finit.

This patch creates a new function finit_task that takes a task_struct
parameter. finit becomes a wrapper that simply calls finit_task with
current. On the plus side this avoids many calls to get_current which
would each resolve to an inline assembler mov instruction.

An empty finit_task has been added to i387.h to avoid linker errors in
case the compiler still emits the call in init_fpu when
CONFIG_MATH_EMULATION is not defined.

The declaration of finit in i387.h has been removed as the remaining
code using this function gets its prototype from fpu_proto.h.
Signed-off-by: NDaniel Glöckner <dg@emlix.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Pallipadi Venkatesh" <venkatesh.pallipadi@intel.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Bill Metzenthen <billm@melbpc.org.au>
LKML-Reference: <E1Lew31-0004il-Fg@mailer.emlix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch provides a high resolution clock/timer source using the
SGI UV system-wide synchronized RTC clock/timer hardware.
Signed-off-by: NDimitri Sivanich <sivanich@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: john stultz <johnstul@us.ibm.com>
LKML-Reference: <20090304185918.GC24419@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch allocates a system interrupt vector for various platform
specific uses.
Signed-off-by: NDimitri Sivanich <sivanich@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: john stultz <johnstul@us.ibm.com>
LKML-Reference: <20090304185605.GA24419@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: Fix boot failure on EFI system with large runtime memory range

Brian Maly reported that some EFI system with large runtime memory
range can not boot. Because the FIX_MAP used to map runtime memory
range is smaller than run time memory range.

This patch fixes this issue by re-implement efi_ioremap() with
init_memory_mapping().
Reported-and-tested-by: NBrian Maly <bmaly@redhat.com>
Signed-off-by: NHuang Ying <ying.huang@intel.com>
Cc: Brian Maly <bmaly@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1236135513.6204.306.camel@yhuang-dev.sh.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: reactivate DMI quirks on EFI hardware

DMI tables are loaded by EFI, so the dmi calls must happen after
efi_init() and not before.

Currently Apple hardware uses DMI to determine the framebuffer mappings
for efifb. Without DMI working you also have no video on MacBook Pro.

This patch resolves the DMI issue for EFI hardware (DMI is now properly
detected at boot), and additionally efifb now loads on Apple hardware
(i.e. video works).
Signed-off-by: NBrian Maly <bmaly@redhat>
Acked-by: NYinghai Lu <yinghai@kernel.org>
Cc: ying.huang@intel.com
LKML-Reference: <49ADEDA3.1030406@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

 arch/x86/kernel/setup.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

Impact: build fix

The APIC code rewrite in the x86 tree broke the x86/mce branch:

 arch/x86/kernel/cpu/mcheck/threshold.c: In function ‘mce_threshold_interrupt’:
 arch/x86/kernel/cpu/mcheck/threshold.c:24: error: implicit declaration of function ‘ack_APIC_irq’

Also tidy up the file a bit while at it.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fix bad frame in rt_sigreturn on 64-bit

After commit 97286a2b some applications
fail to return from signal handler:

[  145.150133] firefox[3250] bad frame in rt_sigreturn frame:00007f902b44eb28 ip:352e80b307 sp:7f902b44ef70 orax:ffffffffffffffff in libpthread-2.9.so[352e800000+17000]
[  665.519017] firefox[5420] bad frame in rt_sigreturn frame:00007faa8deaeb28 ip:352e80b307 sp:7faa8deaef70 orax:ffffffffffffffff in libpthread-2.9.so[352e800000+17000]

The root cause is forgetting to keep 64 byte aligned value of
fpstate for next stack pointer calculation.
Reported-by: NJaswinder Singh Rajput <jaswinder@kernel.org>
Reported-by: NMike Galbraith <efault@gmx.de>
Signed-off-by: NHiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
LKML-Reference: <49AC85C1.7060600@ct.jp.nec.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>