These are defined as static cpumask_var_t so if MAXSMP is not used,
they are cleared already. Avoid surprises when MAXSMP is enabled.
Signed-off-by: Yinghai Lu <yinghai.lu@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
That prefix is already included in the DUMP_printk macro. So there is no
need to repeat it in the format string.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This fixes a bug with a device that could not be assigned to a KVM guest
because it is still assigned to a dma_ops protection domain.
[chrisw: simply remove WARN_ON(), will always fire since dev->driver
will be pci-sub]
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Handling this event causes device assignment in KVM to fail because the
device gets re-attached as soon as the pci-stub registers as the driver
for the device.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Fill in amd_hw_cache_event_id[] with the AMD CPU specific events,
for family 0x0f, 0x10 and 0x11.
There's apparently no distinction between load and store events, so
we only fill in the load events.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Using gcc 3.3.5 a "make allmodconfig" + "CONFIG_KVM=n"
triggers a build error:
arch/x86/mm/built-in.o(.init.text+0x43f7): In function `__change_page_attr':
arch/x86/mm/pageattr.c:114: undefined reference to `__udivdi3'
make: *** [.tmp_vmlinux1] Error 1
The culprit turned out to be a division in arch/x86/mm/memtest.c
For more info see this thread:
http://marc.info/?l=linux-kernel&m=124416232620683
The patch entirely removes the division that caused the build
error.
[ Impact: build fix with certain GCC versions ]
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: xiyou.wangcong@gmail.com
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: <stable@kernel.org>
LKML-Reference: <20090608170939.GB12431@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix bug in the SGI UV macros that support systems with multiple
coherency domains. The macros used for referencing global MMR
(chipset registers) are failing to correctly "or" the NASID
(node identifier) bits that reside above M+N. These high bits
are supplied automatically by the chipset for memory accesses
coming from the processor socket.
However, the bits must be present for references to the special
global MMR space used to map chipset registers. (See uv_hub.h
for more details ...)
The bug results in references to invalid/incorrect nodes.
Signed-off-by: Jack Steiner <steiner@sgi.com>
Cc: <stable@kernel.org>
LKML-Reference: <20090608154405.GA16395@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Standardize and tidy up all the messages we print during
perfcounter initialization.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fill in core2_hw_cache_event_id[] with the Atom model specific events.
The events can be used in all the tools via the -e (--event) parameter,
for example "-e l1-misses" or -"-e l2-accesses" or "-e l2-write-misses".
( Note: these are straight from the Intel manuals - not tested yet.)
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fill in core2_hw_cache_event_id[] with the Core2 model specific events.
The events can be used in all the tools via the -e (--event) parameter,
for example "-e l1-misses" or -"-e l2-accesses" or "-e l2-write-misses".
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
vfree() does its own 'NULL' check, so no need for check before
calling it.
In v2, remove the stray newline.
[ Impact: cleanup ]
Signed-off-by: Figo.zhang <figo1802@gmail.com>
Cc: Dmitry Adamushko <dmitry.adamushko@gmail.com>
LKML-Reference: <1244385036.3402.11.camel@myhost>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This fixes a stack corruption panic or null dereference oops
due to a bad GS in resume_userspace() when returning from
sys_vm86() and calling lockdep_sys_exit().
Only a problem when CONFIG_LOCKDEP and CONFIG_CC_STACKPROTECTOR
enabled.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Cc: H. Peter Anvin <hpa@zytor.com>
LKML-Reference: <1244384628.2323.4.camel@bimbo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar reported that read_apic is buggy novadays:
[ 0.000000] Using APIC driver default
[ 0.000000] SMP: Allowing 1 CPUs, 0 hotplug CPUs
[ 0.000000] Local APIC disabled by BIOS -- you can enable it with "lapic"
[ 0.000000] APIC: disable apic facility
[ 0.000000] ------------[ cut here ]------------
[ 0.000000] WARNING: at arch/x86/kernel/apic/apic.c:254 native_apic_read_dummy+0x2d/0x3b()
[ 0.000000] Hardware name: HP OmniBook PC
Indeed we still rely on apic->read operation for SMP compiled
kernel. And instead of disfigure the SMP code with #ifdef we
allow to call apic->read. To capture any unexpected results
we check for apic->read being called for sane reason via
WARN_ON_ONCE but(!) instead of OR we should use AND logical
operation (thanks Yinghai for spotting the root of the problem).
Along with that we could be have bad MP table and we are
to fix it that way no SMP started and no complains about
BIOS bug if apic was just disabled via command line.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20090607124840.GD4547@lenovo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The Dell Optiplex 360 hangs on reboot, just like the Optiplex 330, so
the same quirk is needed.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Steve Conklin <steve.conklin@canonical.com>
Cc: Leann Ogasawara <leann.ogasawara@canonical.com>
Cc: <stable@kernel.org>
LKML-Reference: <200906051202.38311.jdelvare@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Remove model information, encoding/decoding and reduce bookkeeping.
This, besides removing a lot of code and cleaning up the code, also
enables these features on many more CPUs that were enumerated before.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
LKML-Reference: <1244224637.8212.6.camel@ht.satnam>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge reason: This branch was on an -rc5 base so pull almost-2.6.30
to resync with the latest upstream fixes and make sure
the combination works fine.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
x86/pci: fix mmconfig detection with 32bit near 4g
PCI: use fixed-up device class when configuring device
Extend generic event enumeration with the PERF_TYPE_HW_CACHE
method.
This is a 3-dimensional space:
{ L1-D, L1-I, L2, ITLB, DTLB, BPU } x
{ load, store, prefetch } x
{ accesses, misses }
User-space passes in the 3 coordinates and the kernel provides
a counter. (if the hardware supports that type and if the
combination makes sense.)
Combinations that make no sense produce a -EINVAL.
Combinations that are not supported by the hardware produce -ENOTSUP.
Extend the tools to deal with this, and rewrite the event symbol
parsing code with various popular aliases for the units and
access methods above. So 'l1-cache-miss' and 'l1d-read-ops' are
both valid aliases.
( x86 is supported for now, with the Nehalem event table filled in,
and with Core2 and Atom having placeholder tables. )
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Counter type is a frequently used value and we do a lot of
bit juggling by encoding and decoding it from attr->config.
Clean this up by creating a separate attr->type field.
Also clean up the various similarly complex user-space bits
all around counter attribute management.
The net improvement is significant, and it will be easier
to add a new major type (which is what triggered this cleanup).
(This changes the ABI, all tools are adapted.)
(PowerPC build-tested.)
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The current code to set up the GART as an IOMMU enables GART
translations before it removes the aperture from the kernel memory
map, sets the GART PTEs to UC, sets up the guard and scratch
pages, or does a wbinvd(). This leaves the possibility of cache
aliasing open and can cause system crashes.
Re-order the code so as to enable the GART translations only
after all safeguards are in place and the tlb has been flushed.
AMD has tested this patch on both Istanbul systems and 1st
generation Opteron systems with APG enabled and seen no adverse
effects. Istanbul systems with HT Assist enabled sometimes
see MCE errors due to cache artifacts with the unmodified
code.
Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>
Cc: <stable@kernel.org>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: akpm@linux-foundation.org
Cc: jbarnes@virtuousgeek.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The powernow-k8 driver checks to see that the Performance Control/Status
Registers are declared as FFH (functional fixed hardware) by the BIOS.
However, this check got broken in the commit:
0e64a0c982
[CPUFREQ] checkpatch cleanups for powernow-k8
Fix based on an original patch from Naga Chumbalkar.
Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Cc: Mark Langsdorf <mark.langsdorf@amd.com>
Signed-off-by: Dave Jones <davej@redhat.com>
In order to make arch_vma_name() work from inside
install_special_mapping() we need to set the context.vdso
before calling it.
( This is needed for performance counters to be able to track
this special executable area. )
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We don't set up the canary; let's disable stack protector on boot.c so
we can get into lguest_init, then set it up. As a side effect,
switch_to_new_gdt() sets up %fs for us properly too.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pascal reported and bisected a commit:
| x86/PCI: don't call e820_all_mapped with -1 in the mmconfig case
which broke one system system.
ACPI: Using IOAPIC for interrupt routing
PCI: MCFG configuration 0: base f0000000 segment 0 buses 0 - 255
PCI: MCFG area at f0000000 reserved in ACPI motherboard resources
PCI: Using MMCONFIG for extended config space
it didn't have
PCI: updated MCFG configuration 0: base f0000000 segment 0 buses 0 - 63
anymore, and try to use 0xf000000 - 0xffffffff for mmconfig
For 32bit, mcfg_res->end could be 32bit only (if 64 resources aren't used)
So use end - 1 to pass the value in mcfg->end to avoid overflow.
We don't need to worry about the e820 path, they are always 64 bit.
Reported-by: Pascal Terjan <pterjan@mandriva.com>
Bisected-by: Pascal Terjan <pterjan@mandriva.com>
Tested-by: Pascal Terjan <pterjan@mandriva.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: stable@kernel.org
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Throttling logic is broken and we can lock up with too small
hw sampling intervals.
Make the throttling code more robust: disable counters even
if we already disabled them.
( Also clean up whitespace damage i noticed while reading
various pieces of code related to throttling. )
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The UV tlb shootdown code has a serious initialization error.
An array of structures [32*8] is initialized as if it were [32].
The array is indexed by (cpu number on the blade)*8, so the short
initialization works for up to 4 cpus on a blade.
But above that, we provide an invalid opcode to the hub's
broadcast assist unit.
This patch changes the allocation of the array to use its symbolic
dimensions for better clarity. And initializes all 32*8 entries.
Shortened 'UV_ACTIVATION_DESCRIPTOR_SIZE' to 'UV_ADP_SIZE' per Ingo's
recommendation.
Tested on the UV simulator.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: <stable@kernel.org>
LKML-Reference: <E1M6lZR-0007kV-Aq@eag09.americas.sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In alloc_coherent there is an omitted unlock on the path where mapping
fails. Add the unlock.
[ Impact: fix lock imbalance in alloc_coherent ]
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Remove the IRQ (non-NMI) handling bits as NMI will be used always.
Signed-off-by: Yong Wang <yong.y.wang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090603051255.GA2791@ywang-moblin2.bj.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
git status complains of untracked (generated) files in arch/x86/boot..
# Untracked files:
# (use "git add <file>..." to include in what will be committed)
#
# ../../arch/x86/boot/compressed/mkpiggy
# ../../arch/x86/boot/compressed/piggy.S
# ../../arch/x86/boot/compressed/vmlinux.lds
# ../../arch/x86/boot/voffset.h
# ../../arch/x86/boot/zoffset.h
..so adjust .gitignore files accordingly.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
The structure isn't hw only and when I read event, I think about those
things that fall out the other end. Rename the thing.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
Cc: Stephane Eranian <eranian@googlemail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Do as Power already does, emulate sample periods up to 2^63-1 by
composing them of smaller values limited by hardware capabilities.
Only once we wrap the software period do we generate an overflow
event.
Just 10 lines of new code.
Reported-by: Stephane Eranian <eranian@googlemail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
IRQ (non-NMI) sampling is not used anymore - remove the last few bits.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
A few renames:
s/irq_period/sample_period/
s/irq_freq/sample_freq/
s/PERF_RECORD_/PERF_SAMPLE_/
s/record_type/sample_type/
And change both the new sample_type and read_format to u64.
Reported-by: Stephane Eranian <eranian@googlemail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix the fact that the IOAPIC version number in the x86_64 code path always
gets assigned to 0, instead of the correct value.
Before the patch: (from "dmesg" output):
ACPI: IOAPIC (id[0x08] address[0xfec00000] gsi_base[0])
IOAPIC[0]: apic_id 8, version 0, address 0xfec00000, GSI 0-23 <---
After the patch:
ACPI: IOAPIC (id[0x08] address[0xfec00000] gsi_base[0])
IOAPIC[0]: apic_id 8, version 32, address 0xfec00000, GSI 0-23 <---
History:
io_apic_get_version() was compiled out of the x86_64 code path in the commit
f2c2cca3ac:
Author: Andi Kleen <ak@suse.de>
Date: Tue Sep 26 10:52:37 2006 +0200
[PATCH] Remove APIC version/cpu capability mpparse checking/printing
ACPI went to great trouble to get the APIC version and CPU capabilities
of different CPUs before passing them to the mpparser. But all
that data was used was to print it out. Actually it even faked some data
based on the boot cpu, not on the actual CPU being booted.
Remove all this code because it's not needed.
Cc: len.brown@intel.com
At the time, the IOAPIC version number was deliberately not printed
in the x86_64 code path. However, after the x86 and x86_64 files were
merged, the net result is that the IOAPIC version is printed incorrectly
in the x86_64 code path.
The patch below provides a fix. I have tested it with acpi, and with
acpi=off, and did not see any problems.
Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Acked-by: Yinghai Lu <yhlu.kernel@gmail.com>
LKML-Reference: <20090416014230.4885.94926.sendpatchset@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
*************************
Merge reason: irq/numa didnt build because this commit:
2759c32: x86: don't call read_apic_id if !cpu_has_apic
Had a dependency on x86/cpufeature changes. Pull in that
(small) branch to fix the dependency.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Conflicts:
arch/mips/sibyte/bcm1480/irq.c
arch/mips/sibyte/sb1250/irq.c
Merge reason: we gathered a few conflicts plus update to latest upstream fixes.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge reason: merge almost-rc8 into perfcounters/core, which was -rc6
based - to pick up the latest upstream fixes.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Addresses http://bugzilla.kernel.org/show_bug.cgi?id=13302
On x86 and x86-64, it is possible that page tables are shared beween
shared mappings backed by hugetlbfs. As part of this,
page_table_shareable() checks a pair of vma->vm_flags and they must match
if they are to be shared. All VMA flags are taken into account, including
VM_LOCKED.
The problem is that VM_LOCKED is cleared on fork(). When a process with a
shared memory segment forks() to exec() a helper, there will be shared
VMAs with different flags. The impact is that the shared segment is
sometimes considered shareable and other times not, depending on what
process is checking.
What happens is that the segment page tables are being shared but the
count is inaccurate depending on the ordering of events. As the page
tables are freed with put_page(), bad pmd's are found when some of the
children exit. The hugepage counters also get corrupted and the Total and
Free count will no longer match even when all the hugepage-backed regions
are freed. This requires a reboot of the machine to "fix".
This patch addresses the problem by comparing all flags except VM_LOCKED
when deciding if pagetables should be shared or not for hugetlbfs-backed
mapping.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: <starlight@binnacle.cx>
Cc: Eric B Munson <ebmunson@us.ibm.com>
Cc: Adam Litke <agl@us.ibm.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Always use NMI for performance-monitoring interrupt as there could be
racy situations if we switch between irq and nmi mode frequently.
Signed-off-by: Yong Wang <yong.y.wang@intel.com>
LKML-Reference: <20090529052835.GA13657@ywang-moblin2.bj.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This will test the automatic aperture enlargement code. This is
important because only very few devices will ever trigger this code
path. So force it under CONFIG_IOMMU_STRESS.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Disabling the round-robin allocator results in reusing the same
dma-addresses again very fast. This is a good test if the iotlb flushing
is working correctly.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This patch makes sure no reserved addresses are allocated in an dma_ops
domain when the aperture is increased dynamically.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Simplify the code a little bit by using the same unit for all address
space related state in the dma_ops domain structure.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This patch changes the AMD IOMMU address allocator to allow up to 32
aperture ranges per dma_ops domain.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
The code will be required when the aperture size increases dynamically
in the extended address allocator.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This patch makes sure that no function required for suspend/resume of
AMD IOMMU driver is thrown away after boot.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Current hardware uses msi instead of msi-x so this code it not necessary
and can not be tested. The best thing is to drop this code.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This patch restructures the AMD IOMMU initialization code to initialize
all hardware registers with one single function call.
This is helpful for suspend/resume support.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This patch introduces the for_each_iommu and for_each_iommu_safe macros
to simplify the developers life when having to iterate over all AMD
IOMMUs in the system.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Some drivers may use the dma api during ->remove which will
cause a protection domain to get reattached to a device. Delay the
detach until after the driver is completely unbound.
[ joro: added a little merge helper ]
[ Impact: fix too early device<->domain removal ]
Signed-off-by: Chris Wright <chrisw@redhat.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
The bug never triggered. But it should be fixed to protect against
broken ACPI tables in the future.
[ Impact: protect against broken ivrs acpi table ]
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
The devid parameter to set_dev_entry_from_acpi is the requester ID
rather than the device ID since it is used to index the IOMMU device
table. The handling of IVHD_DEV_ALIAS used to pass the device ID.
This patch fixes it to pass the requester ID.
[ Impact: fix setting the wrong req-id in acpi-table parsing ]
Signed-off-by: Neil Turton <nturton@solarflare.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
The variable amd_iommu_last_bdf holds the maximum bdf of any device
controlled by an IOMMU, so the number of device entries needed is
amd_iommu_last_bdf+1. The function tbl_size used amd_iommu_last_bdf
instead. This would be a problem if the last device were a large
enough power of 2.
[ Impact: fix amd_iommu_last_bdf off-by-one error ]
Signed-off-by: Neil Turton <nturton@solarflare.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This Kconfig option is intended to enable various code paths or
parameters in IOMMU implementations to stress test the code and/or the
hardware. This can also be done by disabling optimizations in the code
when this option is switched on.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Add information about device memory mapping requirements for the IOMMU
as described in the IVRS ACPI table to the kernel log if amd_iommu_dump
was specified on the kernel command line.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Add information about devices belonging to an IOMMU as described in the
IVRS ACPI table to the kernel log if amd_iommu_dump was specified on the
kernel command line.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Add information about IOMMU devices described in the IVRS ACPI table to
the kernel log if amd_iommu_dump was specified on the kernel command
line.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This kernel parameter will be useful to get some AMD IOMMU related
information in dmesg that is not necessary for the default user but may
be helpful in debug situations.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
The *fence instructions were moved to vsyscall_64.c by commit
cb9e35dce9. But this breaks the
vDSO, because vread methods are also called from there.
Besides, the synchronization might be unnecessary for other
time sources than TSC.
[ Impact: fix potential time warp in VDSO ]
Signed-off-by: Petr Tesarik <ptesarik@suse.cz>
LKML-Reference: <9d0ea9ea0f866bdc1f4d76831221ae117f11ea67.1243241859.git.ptesarik@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@kernel.org>
instead of declaring one variant as an inline function...
because other case is a variable
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4A13B344.7030307@kernel.org>
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:
x86: avoid back to back on_each_cpu in cpa_flush_array
x86, relocs: ignore R_386_NONE in kernel relocation entries
Cleanup cpa_flush_array() to avoid back to back on_each_cpu() calls.
[ Impact: optimizes fix 0af48f42df ]
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Slightly modified by trenn@suse.de -> only do this on fam 10h and fam 11h.
Currently powernow-k8 determines CPU frequency from ACPI PSS objects, but
according to AMD family 11h BKDG this frequency is just a rounded value:
"CoreFreq (MHz) = The CPU COF specified by MSRC001_00[6B:64][CpuFid]
rounded to the nearest 100 Mhz."
As a consequnce powernow-k8 reports wrong CPU frequency on some systems,
e.g. on Turion X2 Ultra:
powernow-k8: Found 1 AMD Turion(tm)X2 Ultra DualCore Mobile ZM-82
processors (2 cpu cores) (version 2.20.00)
powernow-k8: 0 : pstate 0 (2200 MHz)
powernow-k8: 1 : pstate 1 (1100 MHz)
powernow-k8: 2 : pstate 2 (600 MHz)
But this is wrong as frequency for Pstate2 is 550 MHz. x86info reports it
correctly:
#x86info -a |grep Pstate
...
Pstate-0: fid=e, did=0, vid=24 (2200MHz)
Pstate-1: fid=e, did=1, vid=30 (1100MHz)
Pstate-2: fid=e, did=2, vid=3c (550MHz) (current)
Solution is to determine the frequency directly from Pstate MSRs instead
of using rounded values from ACPI table.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>
- Make the message shorter and easier to grep for
- Use printk_once instead of WARN_ONCE (functionality of these was mixed)
Signed-off-by: Thomas Renninger <trenn@suse.de>
Cc: Langsdorf, Mark <mark.langsdorf@amd.com>
Signed-off-by: Dave Jones <davej@redhat.com>
arch/x86/kernel/cpu/cpufreq/powernow-k7.c:172: warning: 'invalidate_entry' defined but not used
Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Dave Jones <davej@redhat.com>
Some atom procs don't do freq scaling (such as the atom 330 on my own
littlefalls2 board). By adding the atom family here, we at least get
the benefit of passive cooling in a thermal emergency. Not sure how
to see that its actually helping any, but the driver does bind and
claim its functioning on my atom 330.
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Dave Jones <davej@redhat.com>
We have a debug check that detects stuck NMIs and returns with
the PMU disabled in the global ctrl MSR - but i managed to trigger
a situation where this was not enough to deassert the NMI.
So clear/reset the full PMU and keep the disable count balanced when
exiting from here. This way the box produces a debug warning but
stays up and is more debuggable.
[ Impact: in case of PMU related bugs, recover more gracefully ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
My Nehalem box locks up in certain situations (with an
always-asserted NMI causing a lockup) if the PMU LVT
entry is programmed between NMI and IRQ mode with a
high frequency.
Standardize exlusively on NMIs instead.
[ Impact: fix lockup ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
For relocatable 32bit kernels, boot/compressed/relocs.c processes
relocation entries in the kernel image and appends it to the kernel
image such that boot/compressed/head_32.S can relocate the kernel.
The kernel image is one statically linked object and only uses two
relocation types - R_386_PC32 and R_386_32, of the two only the latter
needs massaging during kernel relocation and thus handled by relocs.
R_386_PC32 is ignored and all other relocation types are considered
error.
When the target of a relocation resides in a discarded section,
binutils doesn't throw away the relocation record but nullifies it by
changing it to R_386_NONE, which unfortunately makes relocs fail.
The problem was triggered by yet out-of-tree x86 stack unwind patches
but given the binutils behavior, ignoring R_386_NONE is the right
thing to do.
The problem has been tracked down to binutils behavior by Jan Beulich.
[ Impact: fix build with certain binutils by ignoring R_386_NONE ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <4A1B8150.40702@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* 'kvm-updates/2.6.30' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: Fix PDPTR reloading on CR4 writes
KVM: Make paravirt tlb flush also reload the PAE PDPTRs
This reverts commit b68f1d2e7a.
It is causing problems (stuck/stuttering profiling) - when mixed
NMI and non-NMI counters are used.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090525153931.703093461@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Introduce a generic per counter interrupt throttle.
This uses the perf_counter_overflow() quick disable to throttle a specific
counter when its going too fast when a pmu->unthrottle() method is provided
which can undo the quick disable.
Power needs to implement both the quick disable and the unthrottle method.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090525153931.703093461@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
remove the x86 specific interrupt throttle
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090525153931.616671838@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Expose the INV and EDGE bits of the PMU to raw configs.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090525153931.494709027@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The processor is documented to reload the PDPTRs while in PAE mode if any
of the CR4 bits PSE, PGE, or PAE change. Linux relies on this
behaviour when zapping the low mappings of PAE kernels during boot.
The code already handled changes to CR4.PAE; augment it to also notice changes
to PSE and PGE.
This triggered while booting an F11 PAE kernel; the futex initialization code
runs before any CR3 reloads and writes to a NULL pointer; the futex subsystem
ended up uninitialized, killing PI futexes and pulseaudio which uses them.
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
The paravirt tlb flush may be used not only to flush TLBs, but also
to reload the four page-directory-pointer-table entries, as it is used
as a replacement for reloading CR3. Change the code to do the entire
CR3 reloading dance instead of simply flushing the TLB.
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
Remap percpu allocator has subtle bug when combined with page
attribute changing. Remap percpu allocator aliases PMD pages for the
first chunk and as pageattr doesn't know about the alias it ends up
updating page attributes of the original mapping thus leaving the
alises in inconsistent state which might lead to subtle data
corruption. Please read the following threads for more information:
http://thread.gmane.org/gmane.linux.kernel/835783
The following is the proposed fix which teaches pageattr about percpu
aliases.
http://thread.gmane.org/gmane.linux.kernel/837157
However, the above changes are deemed too pervasive for upstream
inclusion for 2.6.30 release, so this patch essentially disables
the remap allocator for the time being.
Signed-off-by: Tejun Heo <tj@kernel.org>
LKML-Reference: <4A1A0A27.4050301@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
cpa_flush_array seems to prefer wbinvd() over clflush at 4M threshold.
clflush needs to be done on only one CPU as per instruction definition.
wbinvd() however, should be done on all CPUs.
[ Impact: fix missing flush which could cause data corruption ]
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
wbinvd is supported on all CPUs 486 or later. But,
pageattr.c is checking x86_model >= 4 before wbinvd(), which looks like
an oversight bug. It was first introduced at one place by changeset
d7c8f21a8c and got copied over to second
place in the same file later.
[ Impact: fix missing cache flush on early-model CPUs, potential data corruption ]
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Introduce "noxsave" boot parameter which will disable the cpu's xsave/xrstor
capabilities. Useful for debugging and working around xsave related issues.
[ Impact: make it possible to debug problems in the field ]
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Remove ACPI 3 E820 extended memory attributes support. At least one
vendor actively set all the flags to zero, but left ECX on return at
24. This bug may be present in other BIOSes.
The breakage functionally means the ACPI 3 flags are probably
completely useless, and that no OS any time soon is going to rely on
their existence. Therefore, drop support completely. We may want to
revisit this question in the future, if we find ourselves actually
needing the flags.
This reverts all or part of the following checkins:
cd670599b7c549e71d07
However, retain the part from the latter commit that copies e820 into
a temporary buffer; that is an unrelated BIOS workaround. Put in a
comment to explain that part.
See https://bugzilla.redhat.com/show_bug.cgi?id=499396 for some
additional information.
[ Impact: detect all memory on affected machines ]
Reported-by: Thomas J. Baker <tjb@unh.edu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Len Brown <len.brown@intel.com>
Cc: Chuck Ebbert <cebbert@redhat.com>
Cc: Kyle McMartin <kmcmartin@redhat.com>
Cc: Matt Domsch <matt_domsch@dell.com>
This replaces the struct perf_counter_context in the task_struct with
a pointer to a dynamically allocated perf_counter_context struct. The
main reason for doing is this is to allow us to transfer a
perf_counter_context from one task to another when we do lazy PMU
switching in a later patch.
This has a few side-benefits: the task_struct becomes a little smaller,
we save some memory because only tasks that have perf_counters attached
get a perf_counter_context allocated for them, and we can remove the
inclusion of <linux/perf_counter.h> in sched.h, meaning that we don't
end up recompiling nearly everything whenever perf_counter.h changes.
The perf_counter_context structures are reference-counted and freed
when the last reference is dropped. A context can have references
from its task and the counters on its task. Counters can outlive the
task so it is possible that a context will be freed well after its
task has exited.
Contexts are allocated on fork if the parent had a context, or
otherwise the first time that a per-task counter is created on a task.
In the latter case, we set the context pointer in the task struct
locklessly using an atomic compare-and-exchange operation in case we
raced with some other task in creating a context for the subject task.
This also removes the task pointer from the perf_counter struct. The
task pointer was not used anywhere and would make it harder to move a
context from one task to another. Anything that needed to know which
task a counter was attached to was already using counter->ctx->task.
The __perf_counter_init_context function moves up in perf_counter.c
so that it can be called from find_get_context, and now initializes
the refcount, but is otherwise unchanged.
We were potentially calling list_del_counter twice: once from
__perf_counter_exit_task when the task exits and once from
__perf_counter_remove_from_context when the counter's fd gets closed.
This adds a check in list_del_counter so it doesn't do anything if
the counter has already been removed from the lists.
Since perf_counter_task_sched_in doesn't do anything if the task doesn't
have a context, and leaves cpuctx->task_ctx = NULL, this adds code to
__perf_install_in_context to set cpuctx->task_ctx if necessary, i.e. in
the case where the current task adds the first counter to itself and
thus creates a context for itself.
This also adds similar code to __perf_counter_enable to handle a
similar situation which can arise when the counters have been disabled
using prctl; that also leaves cpuctx->task_ctx = NULL.
[ Impact: refactor counter context management to prepare for new feature ]
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <18966.10075.781053.231153@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
x86: DMI match for the Sony VGN-Z540N as it needs BIOS reboot,
see:
http://bugzilla.kernel.org/show_bug.cgi?id=12901
[ Impact: fix hung reboot on certain systems ]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <1242963350.32574.53.camel@rzhang-dt>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Correct the calculation of ZO_INIT_SIZE (the amount of memory we need
during decompression). One symbol (ZO_startup_32) was missing from
zoffset.h, and another (ZO_z_extract_offset) was misspelled.
[ Impact: build fix ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Peter bisected that:
| commit b9c61b7007
| Date: Wed May 6 10:10:06 2009 -0700
|
| x86/pci: update pirq_enable_irq() to setup io apic routing
|
| So we can set io apic routing only when enabling the device irq.
wrecked his opteron box, ata1 interrupts fail to get through.
ata1 is using irq 11:
[ 1.451839] sata_svw 0000:01:0e.0: version 2.3
[ 1.456333] sata_svw 0000:01:0e.0: PCI INT A -> GSI 11 (level, low) -> IRQ 11
[ 1.463639] scsi0 : sata_svw
[ 1.466949] scsi1 : sata_svw
[ 1.470022] scsi2 : sata_svw
[ 1.473090] scsi3 : sata_svw
[ 1.476112] ata1: SATA max UDMA/133 mmio m8192@0xff3fe000 port 0xff3fe000 irq 11
[ 1.483490] ata2: SATA max UDMA/133 mmio m8192@0xff3fe000 port 0xff3fe100 irq 11
[ 1.490870] ata3: SATA max UDMA/133 mmio m8192@0xff3fe000 port 0xff3fe200 irq 11
[ 1.498247] ata4: SATA max UDMA/133 mmio m8192@0xff3fe000 port 0xff3fe300 irq 11
that pin is overlapped with pin with legacy ones.
We should not set bits in pin_programmed here, so that those bit could
be set later via io_apic_set_pci_routing().
[ Impact: fix boot hang on certain systems ]
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Yinghai Lu <yinghai.lu@kernel.org>
Tested-by: Peter Zijlstra <peterz@infradead.org>
Cc: Jack Steiner <steiner@sgi.com>
LKML-Reference: <4A119990.9020606@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing: Append prompt in /debug/tracing/README file
x86/function-graph: fix constraint for recording old return value
We have to set up the LVT entry only at counter init time, not at
every switch-in time.
There's friction between NMI and non-NMI use here - we'll probably
remove the per counter configurability of it - but until then, dont
slow down things ...
[ Impact: micro-optimization ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Len expressed concern that the update_mptable feature has
side-effects on the ACPI code.
Make it sure explicitly that the code only ever gets called if
the (default disabled) update_mptable boot quirk option is
disabled.
[ Impact: isolate the update_mptable feature from ACPI code more ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4A0DC832.5090200@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
To get all device irq routing and to save them.
This is basically an implicit pci=routeirq enablement if (and on if)
the update_mptable boot option (which is off by default) has been
specified.
[ Impact: extend the update_mptable boot opion's scope ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
LKML-Reference: <4A0DB7B4.4060702@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Jack found a boot crash on a system which doesn't have memory on node0.
It turns out with recent per_cpu changes, node_number for BSP will always
be 0, and it is not consistent to cpu_to_node() that might set it to a
different (nearer) node already.
aka when numa_set_node() for node0 is called early before per_cpu area is
setup:
two places touched that per_cpu(node_number,):
1. in cpu/common.c::cpu_init() and it is not for BP
| #ifdef CONFIG_NUMA
| if (cpu != 0 && percpu_read(node_number) == 0 &&
| cpu_to_node(cpu) != NUMA_NO_NODE)
| percpu_write(node_number, cpu_to_node(cpu));
| #endif
for BP: traps_init ==> cpu_init
for AP: start_secondary ==> cpu_init
2. cpu/intel.c or amd.c::srat_detect_node via numa_set_node()
for BP: check_bugs ==> identify_boot_cpu ==> identify_cpu()
that is rather later before numa_node_id() is used for BP...
for AP: start_secondary => smp_callin => smp_store_cpu_info() =>
=> identify_secondary_cpu => identify_cpu()
so try to set that for BP earlier in setup_per_cpu_areas(), and
don't bother to set that for APs there (it will be updated later
and will be used later)
(and don't mess the 0 before the copying BP per_cpu data to APs)
[ Impact: fix boot crash on memoryless node-0 ]
Reported-and-tested-by: Jack Steiner <steiner@sgi.com>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4A0C4A02.7050401@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Recently there were some changes to the meaning of node_possible_map,
and it is quite strange:
- the node without memory would be set in node_possible_map
- but some node with less NODE_MIN_SIZE will be kicked out of node_possible_map.
fix it by adding strict_setup_node_bootmem().
Also, remove unparse_node().
so result will be:
1. cpu_to_node() will return online node only (nearest one)
2. apicid_to_node() still returns the node that could be not online but is set
in node_possible_map.
3. node_possible_map will include nodes that mem on it are less NODE_MIN_SIZE
v2: after move_cpus_to_node change.
[ Impact: get node_possible_map right ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Tested-by: Jack Steiner <steiner@sgi.com>
LKML-Reference: <4A0C49BE.6080800@kernel.org>
[ v3: various small cleanups and comment clarifications ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
after:
| commit b263295dbf
| Author: Christoph Lameter <clameter@sgi.com>
| Date: Wed Jan 30 13:30:47 2008 +0100
|
| x86: 64-bit, make sparsemem vmemmap the only memory model
we don't have MEMORY_HOTPLUG_RESERVE anymore.
Historically, x86-64 had an architecture-specific method for memory hotplug
whereby it scanned the SRAT for physical memory ranges that could be
potentially used for memory hot-add later. By reserving those ranges
without physical memory, the memmap would be allocated and left dormant
until needed. This depended on the DISCONTIG memory model which has been
removed so the code implementing HOTPLUG_RESERVE is now dead.
This patch removes the dead code used by MEMORY_HOTPLUG_RESERVE.
(Changelog authored by Mel.)
v2: updated changelog, and remove hotadd= in doc
[ Impact: remove dead code ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Reviewed-by: Mel Gorman <mel@csn.ul.ie>
Workflow-found-OK-by: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A0C4910.7090508@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge reason: sync up to -rc6 which has changes to mm/ which we are
going to touch in the commits to follow as well.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
should not call that if apic is disabled.
[ Impact: fix crash on certain UP configs ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
LKML-Reference: <4A09CCBB.2000306@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
according to Ingo, io_apic irq-setup related functions have too many
parameters with a repetitive signature.
So reduce related funcs to get less params by passing a pointer
to a newly defined io_apic_irq_attr structure.
v2: io_apic_irq ==> irq_attr
triggering ==> trigger
v3: add set_io_apic_irq_attr
[ Impact: cleanup ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4A08ACD3.2070401@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The quirk to irq_period unearthed an unrobustness we had in the
hw_counter initialization sequence: we left irq_period at 0, which
was then quirked up to 2 ... which then generated a _lot_ of
interrupts during 'perf stat' runs, slowed them down and skewed
the counter results in general.
Initialize irq_period to the maximum instead.
[ Impact: fix perf stat results ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Xiaohui Xin and some other folks at Intel have been looking into what's
behind the performance hit of paravirt_ops when running native.
It appears that the hit is entirely due to the paravirtualized
spinlocks introduced by:
| commit 8efcbab674
| Date: Mon Jul 7 12:07:51 2008 -0700
|
| paravirt: introduce a "lock-byte" spinlock implementation
The extra call/return in the spinlock path is somehow
causing an increase in the cycles/instruction of somewhere around 2-7%
(seems to vary quite a lot from test to test). The working theory is
that the CPU's pipeline is getting upset about the
call->call->locked-op->return->return, and seems to be failing to
speculate (though I haven't seen anything definitive about the precise
reasons). This doesn't entirely make sense, because the performance
hit is also visible on unlock and other operations which don't involve
locked instructions. But spinlock operations clearly swamp all the
other pvops operations, even though I can't imagine that they're
nearly as common (there's only a .05% increase in instructions
executed).
If I disable just the pv-spinlock calls, my tests show that pvops is
identical to non-pvops performance on native (my measurements show that
it is actually about .1% faster, but Xiaohui shows a .05% slowdown).
Summary of results, averaging 10 runs of the "mmperf" test, using a
no-pvops build as baseline:
nopv Pv-nospin Pv-spin
CPU cycles 100.00% 99.89% 102.18%
instructions 100.00% 100.10% 100.15%
CPI 100.00% 99.79% 102.03%
cache ref 100.00% 100.84% 100.28%
cache miss 100.00% 90.47% 88.56%
cache miss rate 100.00% 89.72% 88.31%
branches 100.00% 99.93% 100.04%
branch miss 100.00% 103.66% 107.72%
branch miss rt 100.00% 103.73% 107.67%
wallclock 100.00% 99.90% 102.20%
The clear effect here is that the 2% increase in CPI is
directly reflected in the final wallclock time.
(The other interesting effect is that the more ops are
out of line calls via pvops, the lower the cache access
and miss rates. Not too surprising, but it suggests that
the non-pvops kernel is over-inlined. On the flipside,
the branch misses go up correspondingly...)
So, what's the fix?
Paravirt patching turns all the pvops calls into direct calls, so
_spin_lock etc do end up having direct calls. For example, the compiler
generated code for paravirtualized _spin_lock is:
<_spin_lock+0>: mov %gs:0xb4c8,%rax
<_spin_lock+9>: incl 0xffffffffffffe044(%rax)
<_spin_lock+15>: callq *0xffffffff805a5b30
<_spin_lock+22>: retq
The indirect call will get patched to:
<_spin_lock+0>: mov %gs:0xb4c8,%rax
<_spin_lock+9>: incl 0xffffffffffffe044(%rax)
<_spin_lock+15>: callq <__ticket_spin_lock>
<_spin_lock+20>: nop; nop /* or whatever 2-byte nop */
<_spin_lock+22>: retq
One possibility is to inline _spin_lock, etc, when building an
optimised kernel (ie, when there's no spinlock/preempt
instrumentation/debugging enabled). That will remove the outer
call/return pair, returning the instruction stream to a single
call/return, which will presumably execute the same as the non-pvops
case. The downsides arel 1) it will replicate the
preempt_disable/enable code at eack lock/unlock callsite; this code is
fairly small, but not nothing; and 2) the spinlock definitions are
already a very heavily tangled mass of #ifdefs and other preprocessor
magic, and making any changes will be non-trivial.
The other obvious answer is to disable pv-spinlocks. Making them a
separate config option is fairly easy, and it would be trivial to
enable them only when Xen is enabled (as the only non-default user).
But it doesn't really address the common case of a distro build which
is going to have Xen support enabled, and leaves the open question of
whether the native performance cost of pv-spinlocks is worth the
performance improvement on a loaded Xen system (10% saving of overall
system CPU when guests block rather than spin). Still it is a
reasonable short-term workaround.
[ Impact: fix pvops performance regression when running native ]
Analysed-by: "Xin Xiaohui" <xiaohui.xin@intel.com>
Analysed-by: "Li Xin" <xin.li@intel.com>
Analysed-by: "Nakajima Jun" <jun.nakajima@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Xen-devel <xen-devel@lists.xensource.com>
LKML-Reference: <4A0B62F7.5030802@goop.org>
[ fixed the help text ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use standard msr-index.h's MSR declaration and no need to declare again.
[ Impact: cleanup, no object code change ]
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Use standard msr-index.h's MSR declaration and no need to declare again.
[ Impact: cleanup, no object code change ]
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Removed MTRR MSR from mtrr/mtrr.h as these are already declared in
msr-index.h and nobody is using them:
MTRRfix16K_A0000_MSR
MTRRfix4K_C8000_MSR
MTRRfix4K_D0000_MSR
MTRRfix4K_D8000_MSR
MTRRfix4K_E0000_MSR
MTRRfix4K_E8000_MSR
MTRRfix4K_F0000_MSR
MTRRfix4K_F8000_MSR
Use standard msr-index.h's MSR declaration and no need to declare again
[ Impact: cleanup, no object code change ]
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Use standard msr-index.h's MSR declaration and no need to declare again
[ Impact: cleanup, no object code change ]
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Use standard msr-index.h's MSR declaration and no need to declare again.
[ Impact: cleanup, no object code change ]
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Use standard msr-index.h's MSR declaration and no need to declare again.
[ Impact: cleanup, no object code change ]
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Instead of specifying the irq_period for a counter, provide a target interrupt
frequency and dynamically adapt the irq_period to match this frequency.
[ Impact: new perf-counter attribute/feature ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20090515132018.646195868@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The treatment of the SP register is different on x86_64 and i386.
This is a regression fix that lived outside the mainline kernel from
2.6.27 to now. The regression was a result of the original merge
consolidation of the i386 and x86_64 archs to x86.
The incorrectly reported SP on i386 prevented stack tracebacks from
working correctly in gdb.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
intel_pmu_handle_irq() can lock up in an infinite loop if the hardware
does not allow the acking of irqs. Alas, this happened in testing so
make this robust and emit a warning if it happens in the future.
Also, clean up the IRQ handlers a bit.
[ Impact: improve perfcounter irq/nmi handling robustness ]
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On certain CPUs i have observed a stuck PMU if interval was set to
1 and NMIs were used. The PMU had PMC0 set in MSR_CORE_PERF_GLOBAL_STATUS,
but it was not possible to ack it via MSR_CORE_PERF_GLOBAL_OVF_CTRL,
and the NMI loop got stuck infinitely.
[ Impact: fix rare hangs during high perfcounter load ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Two consecutive NMIs could daze and confuse the machine when the
first would handle the overflow of both counters.
[ Impact: fix false-positive syslog messages under multi-session profiling ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The current disable/enable mechanism is:
token = hw_perf_save_disable();
...
/* do bits */
...
hw_perf_restore(token);
This works well, provided that the use nests properly. Except we don't.
x86 NMI/INT throttling has non-nested use of this, breaking things. Therefore
provide a reference counter disable/enable interface, where the first disable
disables the hardware, and the last enable enables the hardware again.
[ Impact: refactor, simplify the PMU disable/enable logic ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
perf_counter_unthrottle() restores throttle_ctrl, buts its never set.
Also, we fail to disable all counters when throttling.
[ Impact: fix rare stuck perf-counters when they are throttled ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If counters are disabled globally when a perfcounter IRQ/NMI hits,
and if we throttle in that case, we'll promote the '0' value to
the next lapic IRQ and disable all perfcounters at that point,
permanently ...
Fix it.
[ Impact: fix hung perfcounters under load ]
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Take the counter width into account instead of assuming 32 bits.
In particular Nehalem has 44 bit wide counters, and all
arithmetics should happen on a 44-bit signed integer basis.
[ Impact: fix rare event imprecision, warning message on Nehalem ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If we return -1 in the ops->stack for the stacktrace saving, we end up
breaking out of the loop if the stack we are tracing is in the exception
stack. This causes traces like:
<idle>-0 [002] 34263.745825: raise_softirq_irqoff <-__blk_complete_request
<idle>-0 [002] 34263.745826:
<= 0
<= 0
<= 0
<= 0
<= 0
<= 0
<= 0
By returning "0" instead, the irq stack is saved as well, and we see:
<idle>-0 [003] 883.280992: raise_softirq_irqoff <-__hrtimer_star
t_range_ns
<idle>-0 [003] 883.280992:
<= hrtimer_start_range_ns
<= tick_nohz_restart_sched_tick
<= cpu_idle
<= start_secondary
<=
<= 0
<= 0
[ Impact: record stacks from interrupts ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
After upgrading from gcc 4.2.2 to 4.4.0, the function graph tracer broke.
Investigating, I found that in the asm that replaces the return value,
gcc was using the same register for the old value as it was for the
new value.
mov (addr), old
mov new, (addr)
But if old and new are the same register, we clobber new with old!
I first thought this was a bug in gcc 4.4.0 and reported it:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40132
Andrew Pinski responded (quickly), saying that it was correct gcc behavior
and the code needed to denote old as an "early clobber".
Instead of "=r"(old), we need "=&r"(old).
[Impact: keep function graph tracer from breaking with gcc 4.4.0 ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
mmu.c needs to #include module.h to prevent these warnings:
arch/x86/xen/mmu.c:239: warning: data definition has no type or storage class
arch/x86/xen/mmu.c:239: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL_GPL'
arch/x86/xen/mmu.c:239: warning: parameter names (without types) in function declaration
[ Impact: cleanup ]
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Handle the misconfiguration where CONFIG_PHYSICAL_START is
incompatible with CONFIG_PHYSICAL_ALIGN. This is a configuration
error, but one which arises easily since Kconfig doesn't have the
smarts to express the true relationship between these two variables.
Hence, align __PHYSICAL_START the same way we align LOAD_PHYSICAL_ADDR
in <asm/boot.h>.
For non-relocatable kernels, this would cause the boot to fail.
[ Impact: fix boot failures for non-relocatable kernels ]
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
arch/x86/boot/compressed/misc.c contains several sanity checks on the
output address. Correct constraints that are no longer correct:
- the alignment test should be MIN_KERNEL_ALIGN on both 32 and 64
bits.
- the 64 bit maximum address was set to 2^40, which was the limit of
one specific x86-64 implementation. Change the test to 2^46, the
current Linux limit, and at least try to test the end rather than
the beginning.
- for non-relocatable kernels, test against LOAD_PHYSICAL_ADDR on both
32 and 64 bits.
[ Impact: fix potential boot failure due to invalid tests ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Ed found that on 32-bit, boot_cpu_physical_apicid is not read right,
when the mptable is broken.
Interestingly, actually three paths use/set it:
1. acpi: at that time that is already read from reg
2. mptable: only read from mptable
3. no madt, and no mptable, that use default apic id 0 for 64-bit, -1 for 32-bit
so we could read the apic id for the 2/3 path. We trust the hardware
register more than we trust a BIOS data structure (the mptable).
We can also avoid the double set_fixmap() when acpi_lapic
is used, and also need to move cpu_has_apic earlier and
call apic_disable().
Also when need to update the apic id, we'd better read and
set the apic version as well - so that quirks are applied precisely.
v2: make path 3 with 64bit, use -1 as apic id, so could read it later.
v3: fix whitespace problem pointed out by Ed Swierk
v5: fix boot crash
[ Impact: get correct apic id for bsp other than acpi path ]
Reported-by: Ed Swierk <eswierk@aristanetworks.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <49FC85A9.2070702@kernel.org>
[ v4: sanity-check in the ACPI case too ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge reason: both topics modify the APIC code but were able to do it in
parallel so far. An upcoming patch generates a conflict so
merge them to avoid the conflict.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
With sparse memory, holes should not be marked present for memmap.
This patch makes sure sparsemem really works on SMP mode (!NUMA).
[ Impact: use less memory to map fragmented RAM, avoid boot-OOM/crash ]
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Sheng Yang <sheng.yang@intel.com>
LKML-Reference: <1242117600.22431.0.camel@sli10-desk.sh.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
<stdarg.h> is not needed by these files, remove them.
[ Impact: cleanup ]
Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: akpm@linux-foundation.org
LKML-Reference: <20090512032956.5040.77055.sendpatchset@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge arch_align_stack() and arch_randomize_brk(), since
they are the same.
Tested on x86_64.
[ Impact: cleanup ]
Signed-off-by: Amerigo Wang <amwang@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Solve issues described in 6f66cbc630
in a way that doesn't resort to set_cpus_allowed();
* in fact, only collect_cpu_info and apply_microcode callbacks
must run on a target cpu, others will do just fine on any other.
smp_call_function_single() (as suggested by Ingo) is used to run
these callbacks on a target cpu.
* cleanup of synchronization logic of the 'microcode_core' part
The generic 'microcode_core' part guarantees that only a single cpu
(be it a full-fledged cpu, one of the cores or HT)
is being updated at any particular moment of time.
In general, there is no need for any additional sync. mechanism in
arch-specific parts (the patch removes existing spinlocks).
See also the "Synchronization" section in microcode_core.c.
* return -EINVAL instead of -1 (which is translated into -EPERM) in
microcode_write(), reload_cpu() and mc_sysdev_add(). Other suggestions
for an error code?
* use 'enum ucode_state' as return value of request_microcode_{fw, user}
to gain more flexibility by distinguishing between real error cases
and situations when an appropriate ucode was not found (which is not an
error per-se).
* some minor cleanups
Thanks a lot to Hugh Dickins for review/suggestions/testing!
Reference: http://marc.info/?l=linux-kernel&m=124025889012541&w=2
[ Impact: refactor and clean up microcode driver locking code ]
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Oruba <peter.oruba@amd.com>
Cc: Arjan van de Ven <arjan@infradead.org>
LKML-Reference: <1242078507.5560.9.camel@earth>
[ did some more cleanups ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/include/asm/microcode.h | 25 ++
arch/x86/kernel/microcode_amd.c | 58 ++----
arch/x86/kernel/microcode_core.c | 326 +++++++++++++++++++++-----------------
arch/x86/kernel/microcode_intel.c | 92 +++-------
4 files changed, 261 insertions(+), 240 deletions(-)
(~20 new comment lines)
A long ago, in days of yore, it all began with a god named Thor.
There were vikings and boats and some plans for a Linux kernel
header. Unfortunately, a single 8-bit field was used for bootloader
type and version. This has generally worked without *too* much pain,
but we're getting close to flat running out of ID fields.
Add extension fields for both type and version. The type will be
extended if it the old field is 0xE; the version is a simple MSB
extension.
Keep /proc/sys/kernel/bootloader_type containing
(type << 4) + (ver & 0xf) for backwards compatiblity, but also add
/proc/sys/kernel/bootloader_version which contains the full version
number.
[ Impact: new feature to support more bootloaders ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Update CONFIG_RELOCATABLE, CONFIG_PHYSICAL_START and
CONFIG_PHYSICAL_ALIGN to reflect the current defaults.
[ Impact: make defconfig match Kconfig defaults ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Update defconfigs to reflect current configuration files. No other
changes.
[ Impact: updates defconfigs to match what "make defconfig" generates ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Remove the EXPERIMENTAL tag from CONFIG_RELOCATABLE and make it the
default. Relocatable kernels have been used for a while now, and
should now have identical semantics to non-relocatable kernels when
loaded by a non-relocating bootloader.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Default CONFIG_PHYSICAL_START and CONFIG_PHYSICAL_ALIGN each to 16 MB,
so that both non-relocatable and relocatable kernels are loaded at
16 MB by a non-relocating bootloader. This is somewhat hacky, but it
appears to be the only way to do this that does not break some some
set of existing bootloaders.
We want to avoid the bottom 16 MB because of large page breakup,
memory holes, and ZONE_DMA. Embedded systems may need to reduce this,
or update their bootloaders to be aware of the new min_alignment field.
[ Impact: performance improvement, avoids problems on some systems ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Make the kernel_alignment field adjustable; this allows us to set it
to a large value (intended to be 16 MB to avoid ZONE_DMA contention,
memory holes and other weirdness) while a smart bootloader can still
force a loading at a lesser alignment if absolutely necessary.
Also export pref_address (preferred loading address, corresponding to
the link-time address) and init_size, the total amount of linear
memory the kernel will require during initialization.
[ Impact: allows better kernel placement, gives bootloader more info ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Remove a couple of lines of dead code from
arch/x86/boot/compressed/head_*.S; all of these update registers that
are dead in the current code.
[ Impact: cleanup ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Use ®s->sp instead of regs for getting the top of stack in kernel mode.
(on x86-64, regs->sp always points the top of stack)
[ Impact: Oprofile decodes only stack for backtracing on i386 ]
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
[ v2: rename the API to kernel_stack_pointer(), move variable inside ]
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: systemtap@sources.redhat.com
Cc: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Jan Blunck <jblunck@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
LKML-Reference: <20090511210300.17332.67549.stgit@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix to prevent sched_mc_power_saving from being exported through sysfs
for multi-scoket single core system. Max cores should be always greater than
one (1). My earlier patch that introduced fix for not exporting
'sched_mc_power_saving' on laptops broke it on multi-socket single core
system. This fix addresses issue on both laptop and multi-socket single
core system.
Below are the Test results:
1. Single socket - multi-core
Before Patch: Does not export 'sched_mc_power_saving'
After Patch: Does not export 'sched_mc_power_saving'
Result: Pass
2. Multi Socket - single core
Before Patch: exports 'sched_mc_power_saving'
After Patch: Does not export 'sched_mc_power_saving'
Result: Pass
3. Multi Socket - Multi core
Before Patch: exports 'sched_mc_power_saving'
After Patch: exports 'sched_mc_power_saving'
[ Impact: make the sched_mc_power_saving control available more consistently ]
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: Suresh B Siddha <suresh.b.siddha@intel.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090511143914.GB4853@dirshya.in.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use LOAD_PHYSICAL_ADDR instead of CONFIG_PHYSICAL_START in the 64-bit
decompression code, for equivalence with the 32-bit code.
[ Impact: cleanup, increases code similarity ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Make symbols from the main vmlinux, as opposed to just
compressed/vmlinux, available to header.S. Also, export a few
additional symbols.
This will be used in a subsequent patch to export the total memory
footprint of the kernel.
[ Impact: enable future enhancement ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
- the byte operand constraints were wrong for 32-bit
- the to-op's input operands weren't properly parenthesized
[ Impact: fix possible miscompilation or build failure ]
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
struct thread_struct::ip isn't used on x86_64, struct pt_regs::ip is used
instead.
kgdb should be reading 0 always, but I can't check it.
[ Impact: (potentially) reduce thread_struct size on 64-bit ]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: containers@lists.linux-foundation.org
LKML-Reference: <20090503233015.GJ16631@x200.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
After commit 464d1a78fb aka
"[PATCH] i386: Convert i386 PDA code to use %fs"
%fs saved during context switch moved from thread_struct to pt_regs
and value on thread_struct became unused.
[ Impact: reduce thread_struct size on 32-bit ]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: containers@lists.linux-foundation.org
LKML-Reference: <20090503232952.GI16631@x200.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In case if apic were disabled by boot option
we still need read_apic operation. So fixmap
a fake apic area if needed.
[ Impact: fix boot crash ]
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: yinghai@kernel.org
Cc: eswierk@aristanetworks.com
LKML-Reference: <20090511134140.GH4624@lenovo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Both print_local_APIC (used when apic=debug kernel param is set) and
cpu_debug code missed support for some extended APIC registers that
I'd like to see.
This adds support to show:
- extended APIC feature register
- extended APIC control register
- extended LVT registers
[ Impact: print more debug info ]
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Jaswinder Singh Rajput <jaswinder@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <20090508162350.GO29045@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
KVM optimizes guest port 80 accesses by passthing them through to the host.
Some AMD machines die on port 80 writes, allowing the guest to hard-lock the
host.
Remove the port passthrough to avoid the problem.
Cc: stable@kernel.org
Reported-by: Piotr Jaroszyński <p.jaroszynski@gmail.com>
Tested-by: Piotr Jaroszyński <p.jaroszynski@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
s/PERFMON/perfcounters for perfcounter interrupt throttling warning.
'perfmon' is the CPU feature name that is Intel-only, while we do
throttling in a generic way.
[ Impact: cleanup ]
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
There's no need to use call memory_present() manually on UMA because
initmem_init() sets up early_node_map by calling
e820_register_active_regions().
[ Impact: cleanup ]
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
LKML-Reference: <1241699742.17846.31.camel@penberg-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
64-bit UMA and NUMA versions of paging_init() are almost identical.
Therefore, merge the copy in mm/numa_64.c to mm/init_64.c to remove
duplicate code.
[ Impact: cleanup ]
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
LKML-Reference: <1241699741.17846.30.camel@penberg-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
found one system where cpu address line is 44bits, mtrr printout
is not right:
[ 0.000000] MTRR variable ranges enabled:
[ 0.000000] 0 base 0 00000000 mask FF0 00000000 write-back
[ 0.000000] 1 base 10 00000000 mask FFF 80000000 write-back
[ 0.000000] 2 base 0 80000000 mask FFF 80000000 uncachable
[ 0.000000] 3 base 0 7F800000 mask FFF FF800000 uncachable
Li Zefan and Frederic pointed out the high_width could be -4 some how.
It turns out when phys_addr is 44bit, size_or_mask will be
ffffffff,00000000 so ffs(size_or_mask) will be 0.
Try to check low 32 bit, to get correct high_width.
Signed-off-by: Yinghai Lu <yinghai@kerne.org>
Also-analyzed-by: Frederic Weisbecker <fweisbec@gmail.com>
Also-analyzed-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Zhaolei <zhaolei@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A026540.8060504@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
It is expected that there might be slight differences between the e820
map and the SRAT table and the intention was that 1MB of slack be allowed.
The calculation comparing e820ram and pxmram assumes the units are bytes,
when they are in fact pages. This means 4GB of slack is being allowed,
not 1MB. This patch makes the correct comparison.
comment is from Mel.
[ Impact: don't accept buggy SRATs that could dump up to 4G of RAM ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A03E13E.6050107@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
node_cover_memory() sanity checks the SRAT table by ensuring that all
PXMs cover the memory reported in the e820.
However, when calculating the size of the holes in the e820, it uses
the early_node_map[] which contains information taken from both SRAT
and e820. If the SRAT is missing an entry, then it is not detected
that the SRAT table is incorrect and missing entries.
This patch uses the e820 map to calculate the holes instead of
early_node_map[].
comment is from Mel.
[ Impact: reject incorrect SRAT tables ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A03E10C.60906@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ed found that on 32-bit, boot_cpu_physical_apicid is not read right,
when the mptable is broken.
Interestingly, actually three paths use/set it:
1. acpi: at that time that is already read from reg
2. mptable: only read from mptable
3. no madt, and no mptable, that use default apic id 0 for 64-bit, -1 for 32-bit
so we could read the apic id for the 2/3 path. We trust the hardware
register more than we trust a BIOS data structure (the mptable).
We can also avoid the double set_fixmap() when acpi_lapic
is used, and also need to move cpu_has_apic earlier and
call apic_disable().
Also when need to update the apic id, we'd better read and
set the apic version as well - so that quirks are applied precisely.
v2: make path 3 with 64bit, use -1 as apic id, so could read it later.
v3: fix whitespace problem pointed out by Ed Swierk
[ Impact: get correct apic id for bsp other than acpi path ]
Reported-by: Ed Swierk <eswierk@aristanetworks.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <49FC85A9.2070702@kernel.org>
[ v4: sanity-check in the ACPI case too ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Do this so we can check the range that is mapped before
init_memory_mapping().
To be able to print out meaningful info, we first have to fix
64-bit to have max_pfn_mapped assigned before that call. This
also unifies the code-path a bit.
[ Impact: print more debug info, cleanup ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <49BF0978.40605@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
setup_force_cpu_cap() only have one user (Xen guest code),
but it should not reuse cleared_cpu_cpus, otherwise it
will have problems on SMP.
Need to have a separate cpu_cpus_set array too, for forced-on
flags, beyond the forced-off flags.
Also need to setup handling before all cpus caps are combined.
[ Impact: fix the forced-set CPU feature flag logic ]
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Yinghai Lu <yinghai.lu@kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix fadt version checking
FADT2_REVISION_ID has value 3 aka rev 3 FADT. So need to use >= instead
of >, as other places in the code do.
[ Impact: extend scope of APIC boot quirk ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
So we can set io apic routing only when enabling the device irq.
This is advantageous for IRQ descriptor allocation affinity: if we set up
the IO-APIC entry later, we have a chance to allocate the IRQ descriptor
later and know which device it is on and can set affinity accordingly.
[ Impact: standardize/enhance irq-enabling sequence for mptable irqs ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A01C46E.8000501@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
So we could set io apic routing when ACPI is not enabled.
[ Impact: prepare for new functionality ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4A01C422.5070400@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
To prepare those params for pcibios_irq_enable() to call setup_io_apic_routing().
[ Impact: extend function call API to prepare for new functionality ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A01C406.2040303@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Prepare to call setup_io_apic_routing() in pcibios_irq_enable()
also remove not needed member apic_id.
[ Impact: clean up, prepare for future change ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4A01C3DD.3050104@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The patch to call mp_config_acpi_gsi() from the ACPI IRQ registration
code never got mainline because there were open discussions about it.
This call is needed to properly update the kernel's copy of the mptable,
when the update_mptable boot parameter is needed.
Now that the dust has settled with the APIC unification, and since there
were no objections when the patch was re-submitted, try this again.
[ Impact: fix the update_mptable boot parameter ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4A01C387.7090103@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix the conditions when we stop updating the mptable due to
running out of slots.
[ Impact: fix memory corruption / non-working update_mptable boot parameter ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4A01C3BB.1000609@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Some processors don't have EFER; don't oops if userspace wants us to
read EFER when we check NX.
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
AMDs VMCB does not have an explicit unusable segment descriptor field,
so we emulate it by using "not present". This has to be setup before
the fixups, because this field is used there.
Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Now that the e820 code explicitly reserves 'potentially dangerous'
free physical memory address space to protect ACPI stolen RAM,
there's no need for the rounding quirk in the PCI allocator anymore.
Also, this quirk was open-ended iteration that could end up reserving
a lot of free space and potentially breaking drivers - such as the one
reported by Yannick Roehlly <yannick.roehlly@free.fr> where there's
a PCI device with a large memory resource.
So remove it.
[ Impact: make more of the PCI hole available for assigning pci devices ]
Reported-by: Yannick Roehlly <yannick.roehlly@free.fr>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Jesse Barnes <jesse.barnes@intel.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A01A7C8.5090701@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The point is to take all RAM resources we have, and
_after_ we've added all the resources we've seen in
the E820 tree, we then _also_ try to add fake reserved
entries for any "round up to X" at the end of the RAM
resources.
[ Impact: improve PCI mem-resource allocation robustness, protect "stolen RAM" ]
Reported-by: Yannick Roehlly <yannick.roehlly@free.fr>
Acked-by: Jesse Barnes <jesse.barnes@intel.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: yannick.roehlly@free.fr
LKML-Reference: <4A01A784.2050407@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Determine the compressed code offset (from the kernel runtime address)
at compile time. This allows some minor optimizations in
arch/x86/boot/compressed/head_*.S, but more importantly it makes this
value available to the build process, which will enable a future patch
to export the necessary linear memory footprint into the bzImage
header.
[ Impact: cleanup, future patch enabling ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
In the pre-decompression code, use the appropriate largest possible
rep movs and rep stos to move code and clear bss, respectively. For
reverse copy, do note that the initial values are supposed to be the
address of the first (highest) copy datum, not one byte beyond the end
of the buffer.
rep strings are not necessarily the fastest way to perform these
operations on all current processors, but are likely to be in the
future, and perhaps more importantly, we want to encourage the
architecturally right thing to do here.
This also fixes a couple of trivial inefficiencies on 64 bits.
[ Impact: trivial performance enhancement, increase code similarity ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
The 64-bit code already clears EFLAGS as soon as it has a stack. This
seems like a reasonable precaution, so do it on 32 bits as well.
[ Impact: extra paranoia ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Set up the decompression stack as soon as we know where it needs to
go. That way we have a full-service stack as soon as possible, rather
than relying on the BP_scratch field.
Note that the stack does need to be empty during bss zeroing (or
else the stack needs to be moved out of the bss segment, which is also
an option.)
[ Impact: cleanup, minor paranoia ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>