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11288 commits

Author SHA1 Message Date
Alok Kataria
76fac077db x86, kexec: Make sure to stop all CPUs before exiting the kernel
x86 smp_ops now has a new op, stop_other_cpus which takes a parameter
"wait" this allows the caller to specify if it wants to stop until all
the cpus have processed the stop IPI.  This is required specifically
for the kexec case where we should wait for all the cpus to be stopped
before starting the new kernel.  We now wait for the cpus to stop in
all cases except for panic/kdump where we expect things to be broken
and we are doing our best to make things work anyway.

This patch fixes a legitimate regression, which was introduced during
2.6.30, by commit id 4ef702c10b.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
LKML-Reference: <1286833028.1372.20.camel@ank32.eng.vmware.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: <stable@kernel.org> v2.6.30-36
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-10-21 13:30:44 -07:00
Randy Dunlap
03f1a17cd5 x86/vsmp: Eliminate kconfig dependency warning
Fix kconfig dependency warning to satisfy dependencies:

warning: (X86_VSMP && X86_64 && PCI && X86_EXTENDED_PLATFORM ||
XEN && PARAVIRT_GUEST && (X86_64 || X86_32 && X86_PAE && !X86_VISWS) && X86_CMPXCHG && X86_TSC || KVM_CLOCK && PARAVIRT_GUEST || KVM_GUEST && PARAVIRT_GUEST || LGUEST_GUEST && PARAVIRT_GUEST && X86_32) selects PARAVIRT which has unmet direct dependencies (PARAVIRT_GUEST)

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
LKML-Reference: <20101013210023.9a033222.randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-14 07:04:30 +02:00
Linus Torvalds
509d4486bd Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, numa: For each node, register the memory blocks actually used
  x86, AMD, MCE thresholding: Fix the MCi_MISCj iteration order
  x86, mce, therm_throt.c: Fix missing curly braces in error handling logic
2010-10-13 16:34:23 -07:00
Yinghai Lu
73cf624d02 x86, numa: For each node, register the memory blocks actually used
Russ reported SGI UV is broken recently. He said:

| The SRAT table shows that memory range is spread over two nodes.
|
| SRAT: Node 0 PXM 0 100000000-800000000
| SRAT: Node 1 PXM 1 800000000-1000000000
| SRAT: Node 0 PXM 0 1000000000-1080000000
|
|Previously, the kernel early_node_map[] would show three entries
|with the proper node.
|
|[    0.000000]     0: 0x00100000 -> 0x00800000
|[    0.000000]     1: 0x00800000 -> 0x01000000
|[    0.000000]     0: 0x01000000 -> 0x01080000
|
|The problem is recent community kernel early_node_map[] shows
|only two entries with the node 0 entry overlapping the node 1
|entry.
|
|    0: 0x00100000 -> 0x01080000
|    1: 0x00800000 -> 0x01000000

After looking at the changelog, Found out that it has been broken for a while by
following commit

|commit 8716273cae
|Author: David Rientjes <rientjes@google.com>
|Date:   Fri Sep 25 15:20:04 2009 -0700
|
|    x86: Export srat physical topology

Before that commit, register_active_regions() is called for every SRAT memory
entry right away.

Use nodememblk_range[] instead of nodes[] in order to make sure we
capture the actual memory blocks registered with each node.  nodes[]
contains an extended range which spans all memory regions associated
with a node, but that does not mean that all the memory in between are
included.

Reported-by: Russ Anderson <rja@sgi.com>
Tested-by: Russ Anderson <rja@sgi.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4CB27BDF.5000800@kernel.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@kernel.org> 2.6.33 .34 .35 .36
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-10-11 15:26:15 -07:00
Zachary Amsden
47008cd887 KVM: x86: Move TSC reset out of vmcb_init
The VMCB is reset whenever we receive a startup IPI, so Linux is setting
TSC back to zero happens very late in the boot process and destabilizing
the TSC.  Instead, just set TSC to zero once at VCPU creation time.

Why the separate patch?  So git-bisect is your friend.

Signed-off-by: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-11 12:36:07 +02:00
Zachary Amsden
58877679fd KVM: x86: Fix SVM VMCB reset
On reset, VMCB TSC should be set to zero.  Instead, code was setting
tsc_offset to zero, which passes through the underlying TSC.

Signed-off-by: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-11 12:36:07 +02:00
Borislav Petkov
6dcbfe4f0b x86, AMD, MCE thresholding: Fix the MCi_MISCj iteration order
This fixes possible cases of not collecting valid error info in
the MCE error thresholding groups on F10h hardware.

The current code contains a subtle problem of checking only the
Valid bit of MSR0000_0413 (which is MC4_MISC0 - DRAM
thresholding group) in its first iteration and breaking out if
the bit is cleared.

But (!), this MSR contains an offset value, BlkPtr[31:24], which
points to the remaining MSRs in this thresholding group which
might contain valid information too. But if we bail out only
after we checked the valid bit in the first MSR and not the
block pointer too, we miss that other information.

The thing is, MC4_MISC0[BlkPtr] is not predicated on
MCi_STATUS[MiscV] or MC4_MISC0[Valid] and should be checked
prior to iterating over the MCI_MISCj thresholding group,
irrespective of the MC4_MISC0[Valid] setting.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-11 11:04:36 +02:00
Jin Dongming
b62be8ea9d x86, mce, therm_throt.c: Fix missing curly braces in error handling logic
When the feature PTS is not supported by CPU, the sysfile
package_power_limit_count for package should not be
generated.

This patch is used for fixing missing { and }.

The patch is not complete as there are other error handling
problems in this function - but that can wait until the
merge window.

Signed-off-by: Jin Dongming <jin.dongming@np.css.fujitsu.com>
Reviewed-by: Fenghua Yu <fenghua.yu@initel.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Cc: Brown Len <len.brown@intel.com>
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: lm-sensors@lm-sensors.org <lm-sensors@lm-sensors.org>
LKML-Reference: <4C7625D1.4060201@np.css.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-08 10:29:20 +02:00
Linus Torvalds
34984f54b7 Merge branch 'v2.6.36-rc6-urgent-fixes' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm
* 'v2.6.36-rc6-urgent-fixes' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm:
  xen: do not initialize PV timers on HVM if !xen_have_vector_callback
  xen: do not set xenstored_ready before xenbus_probe on hvm
2010-10-06 09:51:28 -07:00
Linus Torvalds
39c12be86a Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf trace scripting: Fix extern struct definitions
  perf ui hist browser: Fix segfault on 'a' for annotate
  perf tools: Fix build breakage
  perf, x86: Handle in flight NMIs on P4 platform
  oprofile, ARM: Release resources on failure
  oprofile: Add Support for Intel CPU Family 6 / Model 29
2010-10-05 11:57:37 -07:00
Linus Torvalds
5336377d62 modules: Fix module_bug_list list corruption race
With all the recent module loading cleanups, we've minimized the code
that sits under module_mutex, fixing various deadlocks and making it
possible to do most of the module loading in parallel.

However, that whole conversion totally missed the rather obscure code
that adds a new module to the list for BUG() handling.  That code was
doubly obscure because (a) the code itself lives in lib/bugs.c (for
dubious reasons) and (b) it gets called from the architecture-specific
"module_finalize()" rather than from generic code.

Calling it from arch-specific code makes no sense what-so-ever to begin
with, and is now actively wrong since that code isn't protected by the
module loading lock any more.

So this commit moves the "module_bug_{finalize,cleanup}()" calls away
from the arch-specific code, and into the generic code - and in the
process protects it with the module_mutex so that the list operations
are now safe.

Future fixups:
 - move the module list handling code into kernel/module.c where it
   belongs.
 - get rid of 'module_bug_list' and just use the regular list of modules
   (called 'modules' - imagine that) that we already create and maintain
   for other reasons.

Reported-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Adrian Bunk <bunk@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-05 11:29:27 -07:00
Stefano Stabellini
31e7e931cd xen: do not initialize PV timers on HVM if !xen_have_vector_callback
if !xen_have_vector_callback do not initialize PV timer unconditionally
because we still don't know how many cpus are available and if there is
more than one we won't be able to receive the timer interrupts on
cpu > 0.

This patch fixes an hang at boot when Xen does not support vector
callbacks and the guest has multiple vcpus.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
2010-10-05 13:39:23 +01:00
Linus Torvalds
5a4bbd01c8 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] Fix memory leaks in pcc_cpufreq_do_osc
  [CPUFREQ] acpi-cpufreq: add missing __percpu markup
2010-10-04 11:14:21 -07:00
Linus Torvalds
f4a3330d76 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, hpet: Fix bogus error check in hpet_assign_irq()
  x86, irq: Plug memory leak in sparse irq
  x86, cpu: After uncapping CPUID, re-run CPU feature detection
2010-10-01 15:02:41 -07:00
Thomas Gleixner
0219896228 x86, hpet: Fix bogus error check in hpet_assign_irq()
create_irq() returns -1 if the interrupt allocation failed, but the
code checks for irq == 0.

Use create_irq_nr() instead.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Venkatesh Pallipadi <venki@google.com>
LKML-Reference: <alpine.LFD.2.00.1009282310360.2416@localhost6.localdomain6>
Cc: stable@kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-09-30 15:57:35 -07:00
Thomas Gleixner
1cf180c94e x86, irq: Plug memory leak in sparse irq
free_irq_cfg() is not freeing the cpumask_vars in irq_cfg. Fixing this
triggers a use after free caused by the fact that copying struct
irq_cfg is done with memcpy, which copies the pointer not the cpumask.

Fix both places.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
LKML-Reference: <alpine.LFD.2.00.1009282052570.2416@localhost6.localdomain6>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-09-30 15:57:35 -07:00
Pekka Enberg
3682930623 [CPUFREQ] Fix memory leaks in pcc_cpufreq_do_osc
If acpi_evaluate_object() function call doesn't fail, we must kfree()
output.buffer before returning from pcc_cpufreq_do_osc().

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2010-09-30 16:14:23 -04:00
Namhyung Kim
86cf147494 [CPUFREQ] acpi-cpufreq: add missing __percpu markup
acpi_perf_data is a percpu pointer but was missing __percpu markup.
Add it.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2010-09-30 16:14:22 -04:00
Cyrill Gorcunov
03e22198d2 perf, x86: Handle in flight NMIs on P4 platform
Stephane reported we've forgot to guard the P4 platform
against spurious in-flight performance IRQs. Fix it.

This fixes potential spurious 'dazed and confused' NMI
messages.

Reported-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: fweisbec@gmail.com
Cc: peterz@infradead.org
Cc: Robert Richter <robert.richter@amd.com>
Cc: Lin Ming <ming.m.lin@intel.com>
LKML-Reference: <1285815698-4298-1-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-30 09:17:59 +02:00
Namhyung Kim
bd126b23a2 ACPI: add missing __percpu markup in arch/x86/kernel/acpi/cstate.c
cpu_cstate_entry is a percpu pointer
but was missing __percpu markup.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-09-28 21:38:20 -04:00
H. Peter Anvin
d900329e20 x86, cpu: After uncapping CPUID, re-run CPU feature detection
After uncapping the CPUID level, we need to also re-run the CPU
feature detection code.

This resolves kernel bugzilla 16322.

Reported-by: boris64 <bugzilla.kernel.org@boris64.net>
Cc: <stable@kernel.org> v2.6.29..2.6.35
LKML-Reference: <tip-@git.kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-09-28 16:33:14 -07:00
Linus Torvalds
050026feae Merge branch 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Avoid 'constant_test_bit()' misoptimization due to cast to non-volatile
2010-09-27 21:19:27 -07:00
Linus Torvalds
6a6aa2b7e4 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86/amd-iommu: Fix rounding-bug in __unmap_single
  x86/amd-iommu: Work around S3 BIOS bug
  x86/amd-iommu: Set iommu configuration flags in enable-loop
  x86, setup: Fix earlyprintk=serial,0x3f8,115200
  x86, setup: Fix earlyprintk=serial,ttyS0,115200
2010-09-27 12:22:21 -07:00
Linus Torvalds
f0619343ce Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf, x86: Catch spurious interrupts after disabling counters
  tracing/x86: Don't use mcount in kvmclock.c
  tracing/x86: Don't use mcount in pvclock.c
2010-09-27 12:21:48 -07:00
Ingo Molnar
c7a27aa465 Merge branch 'urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile into perf/urgent 2010-09-27 09:48:44 +02:00
Alexander Chumachenko
c9e2fbd909 x86: Avoid 'constant_test_bit()' misoptimization due to cast to non-volatile
While debugging bit_spin_lock() hang, it was tracked down to gcc-4.4
misoptimization of non-inlined constant_test_bit() due to non-volatile
addr when 'const volatile unsigned long *addr' cast to 'unsigned long *'
with subsequent unconditional jump to pause (and not to the test) leading
to hang.

Compiling with gcc-4.3 or disabling CONFIG_OPTIMIZE_INLINING yields inlined
constant_test_bit() and correct jump, thus working around the kernel bug.

Other arches than asm-x86 may implement this slightly differently;
2.6.29 mitigates the misoptimization by changing the function prototype
(commit c4295fbb60) but probably fixing the issue
itself is better.

Signed-off-by: Alexander Chumachenko <ledest@gmail.com>
Signed-off-by: Michael Shigorin <mike@osdn.org.ua>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-09-26 22:43:07 -07:00
Jan Beulich
a46590533a x86/hwmon: fix initialization of coretemp
Using cpuid_eax() to determine feature availability on other than
the current CPU is invalid. And feature availability should also be
checked in the hotplug code path.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Rudolf Marek <r.marek@assembler.cz>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
2010-09-24 11:44:19 -07:00
Robert Richter
63e6be6d98 perf, x86: Catch spurious interrupts after disabling counters
Some cpus still deliver spurious interrupts after disabling a
counter. This caused 'undelivered NMI' messages. This patch
fixes this. Introduced by:

  4177c42: perf, x86: Try to handle unknown nmis with an enabled PMU

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Robert Richter <robert.richter@amd.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: gorcunov@gmail.com <gorcunov@gmail.com>
Cc: fweisbec@gmail.com <fweisbec@gmail.com>
Cc: ying.huang@intel.com <ying.huang@intel.com>
Cc: ming.m.lin@intel.com <ming.m.lin@intel.com>
Cc: yinghai@kernel.org <yinghai@kernel.org>
Cc: andi@firstfloor.org <andi@firstfloor.org>
Cc: eranian@google.com <eranian@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20100915162034.GO13563@erda.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-24 12:21:41 +02:00
Ingo Molnar
7329cf0201 Merge branch 'amd-iommu/2.6.36' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/linux-2.6-iommu into x86/urgent 2010-09-24 11:19:53 +02:00
Joerg Roedel
04e0463e08 x86/amd-iommu: Fix rounding-bug in __unmap_single
In the __unmap_single function the dma_addr is rounded down
to a page boundary before the dma pages are unmapped. The
address is later also used to flush the TLB entries for that
mapping. But without the offset into the dma page the amount
of pages to flush might be miscalculated in the TLB flushing
path. This patch fixes this bug by using the original
address to flush the TLB.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2010-09-23 16:26:20 +02:00
Joerg Roedel
4c894f47bb x86/amd-iommu: Work around S3 BIOS bug
This patch adds a workaround for an IOMMU BIOS problem to
the AMD IOMMU driver. The result of the bug is that the
IOMMU does not execute commands anymore when the system
comes out of the S3 state resulting in system failure. The
bug in the BIOS is that is does not restore certain hardware
specific registers correctly. This workaround reads out the
contents of these registers at boot time and restores them
on resume from S3. The workaround is limited to the specific
IOMMU chipset where this problem occurs.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2010-09-23 16:26:03 +02:00
Joerg Roedel
e9bf519711 x86/amd-iommu: Set iommu configuration flags in enable-loop
This patch moves the setting of the configuration and
feature flags out out the acpi table parsing path and moves
it into the iommu-enable path. This is needed to reliably
fix resume-from-s3.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2010-09-23 16:24:50 +02:00
Steven Rostedt
258af47479 tracing/x86: Don't use mcount in kvmclock.c
The guest can use the paravirt clock in kvmclock.c which is used
by sched_clock(), which in turn is used by the tracing mechanism
for timestamps, which leads to infinite recursion.

Disable mcount/tracing for kvmclock.o.

Cc: stable@kernel.org
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-22 23:01:19 -04:00
Jeremy Fitzhardinge
9ecd4e1689 tracing/x86: Don't use mcount in pvclock.c
When using a paravirt clock, pvclock.c can be used by sched_clock(),
which in turn is used by the tracing mechanism for timestamps,
which leads to infinite recursion.

Disable mcount/tracing for pvclock.o.

Cc: stable@kernel.org
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
LKML-Reference: <4C9A9A3F.4040201@goop.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-22 23:00:50 -04:00
Linus Torvalds
87ac6fa26e Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  hw breakpoints: Fix pid namespace bug
  x86: Fix instruction breakpoint encoding
  oprofile: Add Support for Intel CPU Family 6 / Model 22 (Intel Celeron 540)
  kprobes: Fix Kconfig dependency
2010-09-21 13:21:42 -07:00
Yinghai Lu
74b3c444a9 x86, setup: Fix earlyprintk=serial,0x3f8,115200
earlyprintk can take and I/O port, so we need to handle this case in
the setup code too, otherwise 0x3f8 will be treated as a baud rate.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4C7B05A6.4010801@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-09-21 10:18:33 -07:00
Yinghai Lu
83d9f65bda x86, setup: Fix earlyprintk=serial,ttyS0,115200
Torsten reported that there is garbage output,
after commit 8fee13a48e (x86,
setup: enable early console output from the decompressor)

It turns out we missed the offset for that case.

Reported-by: Torsten Kaiser <just.for.lkml@googlemail.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4C7B0578.8090807@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-09-21 10:18:14 -07:00
Jiri Olsa
bb7ab785ad oprofile: Add Support for Intel CPU Family 6 / Model 29
This patch adds CPU type detection for dunnington processor (Family 6
/ Model 29) to be identified as core 2 family cpu type (wikipedia
source).

I tested oprofile on Intel(R) Xeon(R) CPU E7440 reporting itself as
model 29, and it runs without an issue.

Spec:

 http://www.intel.com/Assets/en_US/PDF/specupdate/320336.pdf

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Cc: stable@kernel.org
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-09-21 12:22:48 +02:00
Rusty Russell
9b6efcd2e2 lguest: update comments to reflect LHCALL_LOAD_GDT_ENTRY.
We used to have a hypercall which reloaded the entire GDT, then we
switched to one which loaded a single entry (to match the IDT code).

Some comments were not updated, so fix them.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reported by: Eviatar Khen <eviatarkhen@gmail.com>
2010-09-21 10:54:02 +09:30
Linus Torvalds
a5b617368c Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: hpet: Work around hardware stupidity
  x86, build: Disable -fPIE when compiling with CONFIG_CC_STACKPROTECTOR=y
  x86, cpufeature: Suppress compiler warning with gcc 3.x
  x86, UV: Fix initialization of max_pnode
2010-09-16 19:38:08 -07:00
Frederic Weisbecker
89e45aac42 x86: Fix instruction breakpoint encoding
Lengths and types of breakpoints are encoded in a half byte
into CPU registers. However when we extract these values
and store them, we add a high half byte part to them: 0x40 to the
length and 0x80 to the type.
When that gets reloaded to the CPU registers, the high part
is masked.

While making the instruction breakpoints available for perf,
I zapped that high part on instruction breakpoint encoding
and that broke the arch -> generic translation used by ptrace
instruction breakpoints. Writing dr7 to set an inst breakpoint
was then failing.

There is no apparent reason for these high parts so we could get
rid of them altogether. That's an invasive change though so let's
do that later and for now fix the problem by restoring that inst
breakpoint high part encoding in this sole patch.

Reported-by: Kelvie Wong <kelvie@ieee.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
2010-09-17 03:24:13 +02:00
Patrick Simmons
c33f543d32 oprofile: Add Support for Intel CPU Family 6 / Model 22 (Intel Celeron 540)
This patch adds CPU type detection for the Intel Celeron 540, which is
part of the Core 2 family according to Wikipedia; the family and ID pair
is absent from the Volume 3B table referenced in the source code
comments.  I have tested this patch on an Intel Celeron 540 machine
reporting itself as Family 6 Model 22, and OProfile runs on the machine
without issue.

Spec:

 http://download.intel.com/design/mobile/SPECUPDT/317667.pdf

Signed-off-by: Patrick Simmons <linuxrocks123@netscape.net>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: stable@kernel.org
Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-09-16 12:35:56 +02:00
Roland McGrath
eefdca043e x86-64, compat: Retruncate rax after ia32 syscall entry tracing
In commit d4d6715, we reopened an old hole for a 64-bit ptracer touching a
32-bit tracee in system call entry.  A %rax value set via ptrace at the
entry tracing stop gets used whole as a 32-bit syscall number, while we
only check the low 32 bits for validity.

Fix it by truncating %rax back to 32 bits after syscall_trace_enter,
in addition to testing the full 64 bits as has already been added.

Reported-by: Ben Hawkes <hawkes@sota.gen.nz>
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-09-14 16:08:47 -07:00
H. Peter Anvin
36d001c70d x86-64, compat: Test %rax for the syscall number, not %eax
On 64 bits, we always, by necessity, jump through the system call
table via %rax.  For 32-bit system calls, in theory the system call
number is stored in %eax, and the code was testing %eax for a valid
system call number.  At one point we loaded the stored value back from
the stack to enforce zero-extension, but that was removed in checkin
d4d6715016.  An actual 32-bit process
will not be able to introduce a non-zero-extended number, but it can
happen via ptrace.

Instead of re-introducing the zero-extension, test what we are
actually going to use, i.e. %rax.  This only adds a handful of REX
prefixes to the code.

Reported-by: Ben Hawkes <hawkes@sota.gen.nz>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@kernel.org>
Cc: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
2010-09-14 16:08:46 -07:00
H. Peter Anvin
c41d68a513 compat: Make compat_alloc_user_space() incorporate the access_ok()
compat_alloc_user_space() expects the caller to independently call
access_ok() to verify the returned area.  A missing call could
introduce problems on some architectures.

This patch incorporates the access_ok() check into
compat_alloc_user_space() and also adds a sanity check on the length.
The existing compat_alloc_user_space() implementations are renamed
arch_compat_alloc_user_space() and are used as part of the
implementation of the new global function.

This patch assumes NULL will cause __get_user()/__put_user() to either
fail or access userspace on all architectures.  This should be
followed by checking the return value of compat_access_user_space()
for NULL in the callers, at which time the access_ok() in the callers
can also be removed.

Reported-by: Ben Hawkes <hawkes@sota.gen.nz>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: James Bottomley <jejb@parisc-linux.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: <stable@kernel.org>
2010-09-14 16:08:45 -07:00
Thomas Gleixner
54ff7e595d x86: hpet: Work around hardware stupidity
This more or less reverts commits 08be979 (x86: Force HPET
readback_cmp for all ATI chipsets) and 30a564be (x86, hpet: Restrict
read back to affected ATI chipsets) to the status of commit 8da854c
(x86, hpet: Erratum workaround for read after write of HPET
comparator).

The delta to commit 8da854c is mostly comments and the change from
WARN_ONCE to printk_once as we know the call path of this function
already.

This needs really in depth explanation:

First of all the HPET design is a complete failure. Having a counter
compare register which generates an interrupt on matching values
forces the software to do at least one superfluous readback of the
counter register.

While it is nice in theory to program "absolute" time events it is
practically useless because the timer runs at some absurd frequency
which can never be matched to real world units. So we are forced to
calculate a relative delta and this forces a readout of the actual
counter value, adding the delta and programming the compare
register. When the delta is small enough we run into the danger that
we program a compare value which is already in the past. Due to the
compare for equal nature of HPET we need to read back the counter
value after writing the compare rehgister (btw. this is necessary for
absolute timeouts as well) to make sure that we did not miss the timer
event. We try to work around that by setting the minimum delta to a
value which is larger than the theoretical time which elapses between
the counter readout and the compare register write, but that's only
true in theory. A NMI or SMI which hits between the readout and the
write can easily push us beyond that limit. This would result in
waiting for the next HPET timer interrupt until the 32bit wraparound
of the counter happens which takes about 306 seconds.

So we designed the next event function to look like:

   match = read_cnt() + delta;
   write_compare_ref(match);
   return read_cnt() < match ? 0 : -ETIME;

At some point we got into trouble with certain ATI chipsets. Even the
above "safe" procedure failed. The reason was that the write to the
compare register was delayed probably for performance reasons. The
theory was that they wanted to avoid the synchronization of the write
with the HPET clock, which is understandable. So the write does not
hit the compare register directly instead it goes to some intermediate
register which is copied to the real compare register in sync with the
HPET clock. That opens another window for hitting the dreaded "wait
for a wraparound" problem.

To work around that "optimization" we added a read back of the compare
register which either enforced the update of the just written value or
just delayed the readout of the counter enough to avoid the issue. We
unfortunately never got any affirmative info from ATI/AMD about this.

One thing is sure, that we nuked the performance "optimization" that
way completely and I'm pretty sure that the result is worse than
before some HW folks came up with those.

Just for paranoia reasons I added a check whether the read back
compare register value was the same as the value we wrote right
before. That paranoia check triggered a couple of years after it was
added on an Intel ICH9 chipset. Venki added a workaround (commit
8da854c) which was reading the compare register twice when the first
check failed. We considered this to be a penalty in general and
restricted the readback (thus the wasted CPU cycles) to the known to
be affected ATI chipsets.

This turned out to be a utterly wrong decision. 2.6.35 testers
experienced massive problems and finally one of them bisected it down
to commit 30a564be which spured some further investigation.

Finally we got confirmation that the write to the compare register can
be delayed by up to two HPET clock cycles which explains the problems
nicely. All we can do about this is to go back to Venki's initial
workaround in a slightly modified version.

Just for the record I need to say, that all of this could have been
avoided if hardware designers and of course the HPET committee would
have thought about the consequences for a split second. It's out of my
comprehension why designing a working timer is so hard. There are two
ways to achieve it:

 1) Use a counter wrap around aware compare_reg <= counter_reg
    implementation instead of the easy compare_reg == counter_reg

    Downsides:

	- It needs more silicon.

	- It needs a readout of the counter to apply a relative
	  timeout. This is necessary as the counter does not run in
	  any useful (and adjustable) frequency and there is no
	  guarantee that the counter which is used for timer events is
	  the same which is used for reading the actual time (and
	  therefor for calculating the delta)

    Upsides:

	- None

  2) Use a simple down counter for relative timer events

    Downsides:

	- Absolute timeouts are not possible, which is not a problem
	  at all in the context of an OS and the expected
	  max. latencies/jitter (also see Downsides of #1)

   Upsides:

	- It needs less or equal silicon.

	- It works ALWAYS

	- It is way faster than a compare register based solution (One
	  write versus one write plus at least one and up to four
	  reads)

I would not be so grumpy about all of this, if I would not have been
ignored for many years when pointing out these flaws to various
hardware folks. I really hate timers (at least those which seem to be
designed by janitors).

Though finally we got a reasonable explanation plus a solution and I
want to thank all the folks involved in chasing it down and providing
valuable input to this.

Bisected-by: Nix <nix@esperi.org.uk>
Reported-by: Artur Skawina <art.08.09@gmail.com>
Reported-by: Damien Wyart <damien.wyart@free.fr>
Reported-by: John Drescher <drescherjm@gmail.com>
Cc: Venkatesh Pallipadi <venki@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: stable@kernel.org
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-09-15 00:55:13 +02:00
basile@opensource.dyc.edu
08c2b394b9 x86, build: Disable -fPIE when compiling with CONFIG_CC_STACKPROTECTOR=y
The arch/x86/Makefile uses scripts/gcc-x86_$(BITS)-has-stack-protector.sh
to check if cc1 supports -fstack-protector.  When -fPIE is passed to cc1,
these scripts fail causing stack protection to be disabled even when it
is available.

This fix is similar to commit c47efe5548

Reported-by: Kai Dietrich <mail@cleeus.de>
Signed-off-by: Magnus Granberg <zorry@gentoo.org>
LKML-Reference: <20100913101319.748A1148E216@opensource.dyc.edu>
Signed-off-by: Anthony G. Basile <basile@opensource.dyc.edu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-09-13 15:53:16 -07:00
Tetsuo Handa
2fd818642a x86, cpufeature: Suppress compiler warning with gcc 3.x
Gcc 3.x generates a warning

  arch/x86/include/asm/cpufeature.h: In function `__static_cpu_has':
  arch/x86/include/asm/cpufeature.h:326: warning: asm operand 1 probably doesn't match constraints

on each file.
But static_cpu_has() for gcc 3.x does not need __static_cpu_has().

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
LKML-Reference: <201008300127.o7U1RC6Z044051@www262.sakura.ne.jp>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-09-13 14:48:41 -07:00
Peter Zijlstra
5ee5e97ee9 x86, tsc: Fix a preemption leak in restore_sched_clock_state()
A real life genuine preemption leak..

Reported-and-tested-by: Jeff Chua <jeff.chua.linux@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-10 18:17:45 -07:00
Jack Steiner
36ac4b987b x86, UV: Fix initialization of max_pnode
Fix calculation of "max_pnode" for systems where the the highest
blade has neither cpus or memory. (And, yes, although rare this
does occur).

Signed-off-by: Jack Steiner <steiner@sgi.com>
LKML-Reference: <20100910150808.GA19802@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-10 17:15:49 +02:00