Commit Graph

6635 Commits

Author SHA1 Message Date
Matthew Garrett
5bcd757f93 x86/amd-iommu: Reenable AMD IOMMU if it's mysteriously vanished over suspend
AMD's reference BIOS code had a bug that could result in the
firmware failing to reenable the iommu on resume. It
transpires that this causes certain less than desirable
behaviour when it comes to PCI accesses, to whit them ending
up somewhere near Bristol when the more desirable outcome
was Edinburgh. Sadness ensues, perhaps along with filesystem
corruption.  Let's make sure that it gets turned back on,
and that we restore its configuration so decisions it makes
bear some resemblance to those made by reasonable people
rather than crack-addled lemurs who spent all your DMA on
Thunderbird.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2010-10-13 11:11:46 +02:00
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
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
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
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
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
Linus Torvalds
1faa6ec8cc 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, mcheck: Avoid duplicate sysfs links/files for thresholding banks
  io-mapping: Fix the address space annotations
  x86: Fix the address space annotations of iomap_atomic_prot_pfn()
  x86, mm: Fix CONFIG_VMSPLIT_1G and 2G_OPT trampoline
  x86, hwmon: Fix unsafe smp_processor_id() in thermal_throttle_add_dev
2010-09-08 11:14:10 -07:00
Linus Torvalds
899edae615 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: Try to handle unknown nmis with an enabled PMU
  perf, x86: Fix handle_irq return values
  perf, x86: Fix accidentally ack'ing a second event on intel perf counter
  oprofile, x86: fix init_sysfs() function stub
  lockup_detector: Sync touch_*_watchdog back to old semantics
  tracing: Fix a race in function profile
  oprofile, x86: fix init_sysfs error handling
  perf_events: Fix time tracking for events with pid != -1 and cpu != -1
  perf: Initialize callchains roots's childen hits
  oprofile: fix crash when accessing freed task structs
2010-09-08 11:13:16 -07:00
Andreas Herrmann
1389298f7d x86, mcheck: Avoid duplicate sysfs links/files for thresholding banks
kobject_add_internal failed for threshold_bank2 with -EEXIST,
don't try to register things with the same name in the same
directory:

  Pid: 1, comm: swapper Tainted: G        W  2.6.31 #1
  Call Trace:
  [<ffffffff81161b07>] ? kobject_add_internal+0x156/0x180
  [<ffffffff81161cc0>] ? kobject_add+0x66/0x6b
  [<ffffffff81161793>] ? kobject_init+0x42/0x82
  [<ffffffff81161cf9>] ? kobject_create_and_add+0x34/0x63
  [<ffffffff81393963>] ? threshold_create_bank+0x14f/0x259
  [<ffffffff8139310a>] ? mce_create_device+0x8d/0x1b8
  [<ffffffff81646497>] ? threshold_init_device+0x3f/0x80
  [<ffffffff81646458>] ? threshold_init_device+0x0/0x80
  [<ffffffff81009050>] ? do_one_initcall+0x4f/0x143
  [<ffffffff816413a0>] ? kernel_init+0x14c/0x1a2
  [<ffffffff8100c8da>] ? child_rip+0xa/0x20
  [<ffffffff81641254>] ? kernel_init+0x0/0x1a2
  [<ffffffff8100c8d0>] ? child_rip+0x0/0x20
  kobject_create_and_add: kobject_add error: -17

(Probably the for_each_cpu loop should be entirely removed.)

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
LKML-Reference: <20100827092006.GB5348@loge.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-05 14:35:49 +02:00
Robert Richter
4177c42a63 perf, x86: Try to handle unknown nmis with an enabled PMU
When the PMU is enabled it is valid to have unhandled nmis, two
events could trigger 'simultaneously' raising two back-to-back
NMIs. If the first NMI handles both, the latter will be empty
and daze the CPU.

The solution to avoid an 'unknown nmi' massage in this case was
simply to stop the nmi handler chain when the PMU is enabled by
stating the nmi was handled. This has the drawback that a) we
can not detect unknown nmis anymore, and b) subsequent nmi
handlers are not called.

This patch addresses this. Now, we check this unknown NMI if it
could be a PMU back-to-back NMI. Otherwise we pass it and let
the kernel handle the unknown nmi.

This is a debug log:

 cpu #6, nmi #32333, skip_nmi #32330, handled = 1, time = 1934364430
 cpu #6, nmi #32334, skip_nmi #32330, handled = 1, time = 1934704616
 cpu #6, nmi #32335, skip_nmi #32336, handled = 2, time = 1936032320
 cpu #6, nmi #32336, skip_nmi #32336, handled = 0, time = 1936034139
 cpu #6, nmi #32337, skip_nmi #32336, handled = 1, time = 1936120100
 cpu #6, nmi #32338, skip_nmi #32336, handled = 1, time = 1936404607
 cpu #6, nmi #32339, skip_nmi #32336, handled = 1, time = 1937983416
 cpu #6, nmi #32340, skip_nmi #32341, handled = 2, time = 1938201032
 cpu #6, nmi #32341, skip_nmi #32341, handled = 0, time = 1938202830
 cpu #6, nmi #32342, skip_nmi #32341, handled = 1, time = 1938443743
 cpu #6, nmi #32343, skip_nmi #32341, handled = 1, time = 1939956552
 cpu #6, nmi #32344, skip_nmi #32341, handled = 1, time = 1940073224
 cpu #6, nmi #32345, skip_nmi #32341, handled = 1, time = 1940485677
 cpu #6, nmi #32346, skip_nmi #32347, handled = 2, time = 1941947772
 cpu #6, nmi #32347, skip_nmi #32347, handled = 1, time = 1941949818
 cpu #6, nmi #32348, skip_nmi #32347, handled = 0, time = 1941951591
 Uhhuh. NMI received for unknown reason 00 on CPU 6.
 Do you have a strange power saving mode enabled?
 Dazed and confused, but trying to continue

Deltas:

 nmi #32334 340186
 nmi #32335 1327704
 nmi #32336 1819      <<<< back-to-back nmi [1]
 nmi #32337 85961
 nmi #32338 284507
 nmi #32339 1578809
 nmi #32340 217616
 nmi #32341 1798      <<<< back-to-back nmi [2]
 nmi #32342 240913
 nmi #32343 1512809
 nmi #32344 116672
 nmi #32345 412453
 nmi #32346 1462095   <<<< 1st nmi (standard) handling 2 counters
 nmi #32347 2046      <<<< 2nd nmi (back-to-back) handling one
 counter nmi #32348 1773      <<<< 3rd nmi (back-to-back)
 handling no counter! [3]

For  back-to-back nmi detection there are the following rules:

The PMU nmi handler was handling more than one counter and no
counter was handled in the subsequent nmi (see [1] and [2]
above).

There is another case if there are two subsequent back-to-back
nmis [3]. The 2nd is detected as back-to-back because the first
handled more than one counter. If the second handles one counter
and the 3rd handles nothing, we drop the 3rd nmi because it
could be a back-to-back nmi.

Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
[ renamed nmi variable to pmu_nmi to avoid clash with .nmi in entry.S ]
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: peterz@infradead.org
Cc: gorcunov@gmail.com
Cc: fweisbec@gmail.com
Cc: ying.huang@intel.com
Cc: ming.m.lin@intel.com
Cc: eranian@google.com
LKML-Reference: <1283454469-1909-3-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-03 08:05:18 +02:00
Peter Zijlstra
de725dec9d perf, x86: Fix handle_irq return values
Now that we rely on the number of handled overflows, ensure all
handle_irq implementations actually return the right number.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: peterz@infradead.org
Cc: robert.richter@amd.com
Cc: gorcunov@gmail.com
Cc: fweisbec@gmail.com
Cc: ying.huang@intel.com
Cc: ming.m.lin@intel.com
Cc: eranian@google.com
LKML-Reference: <1283454469-1909-4-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-03 08:05:18 +02:00
Don Zickus
2e556b5b32 perf, x86: Fix accidentally ack'ing a second event on intel perf counter
During testing of a patch to stop having the perf subsytem
swallow nmis, it was uncovered that Nehalem boxes were randomly
getting unknown nmis when using the perf tool.

Moving the ack'ing of the PMI closer to when we get the status
allows the hardware to properly re-set the PMU bit signaling
another PMI was triggered during the processing of the first
PMI.  This allows the new logic for dealing with the
shortcomings of multiple PMIs to handle the extra NMI by
'eat'ing it later.

Now one can wonder why are we getting a second PMI when we
disable all the PMUs in the begining of the NMI handler to
prevent such a case, for that I do not know.  But I know the fix
below helps deal with this quirk.

Tested on multiple Nehalems where the problem was occuring.
With the patch, the code now loops a second time to handle the
second PMI (whereas before it was not).

Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: peterz@infradead.org
Cc: robert.richter@amd.com
Cc: gorcunov@gmail.com
Cc: fweisbec@gmail.com
Cc: ying.huang@intel.com
Cc: ming.m.lin@intel.com
Cc: eranian@google.com
LKML-Reference: <1283454469-1909-2-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-03 08:05:17 +02:00
Linus Torvalds
d4348c6789 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, Pentium4: Clear the P4_CCCR_FORCE_OVF flag
  tracing/trace_stack: Fix stack trace on ppc64
2010-08-25 10:50:07 -07:00
Linus Torvalds
5e686019df Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, tsc, sched: Recompute cyc2ns_offset's during resume from sleep states
  sched: Fix rq->clock synchronization when migrating tasks
2010-08-25 08:40:56 -07:00
Lin Ming
8d33091992 perf, x86, Pentium4: Clear the P4_CCCR_FORCE_OVF flag
If on Pentium4 CPUs the FORCE_OVF flag is set then an NMI happens
on every event, which can generate a flood of NMIs. Clear it.

Reported-by: Vince Weaver <vweaver1@eecs.utk.edu>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-08-25 15:15:33 +02:00
Hugh Dickins
b7d4608977 x86, mm: Fix CONFIG_VMSPLIT_1G and 2G_OPT trampoline
rc2 kernel crashes when booting second cpu on this CONFIG_VMSPLIT_2G_OPT
laptop: whereas cloning from kernel to low mappings pgd range does need
to limit by both KERNEL_PGD_PTRS and KERNEL_PGD_BOUNDARY, cloning kernel
pgd range itself must not be limited by the smaller KERNEL_PGD_BOUNDARY.

Signed-off-by: Hugh Dickins <hughd@google.com>
LKML-Reference: <alpine.LSU.2.00.1008242235120.2515@sister.anvils>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-08-24 23:05:17 -07:00
Linus Torvalds
3dc8d7f07e Merge branch 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: PIT: free irq source id in handling error path
  KVM: destroy workqueue on kvm_create_pit() failures
  KVM: fix poison overwritten caused by using wrong xstate size
2010-08-22 11:27:36 -07:00
Sergey Senozhatsky
51e3c1b558 x86, hwmon: Fix unsafe smp_processor_id() in thermal_throttle_add_dev
Fix BUG: using smp_processor_id() in preemptible thermal_throttle_add_dev.
We know the cpu number when calling thermal_throttle_add_dev, so we can
remove smp_processor_id call in thermal_throttle_add_dev by supplying
the cpu number as argument.

This should resolve kernel bugzilla 16615/16629.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
LKML-Reference: <20100820073634.GB5209@swordfish.minsk.epam.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Joerg Roedel <Joerg.Roedel@amd.com>
Cc: Maciej Rutecki <maciej.rutecki@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-08-20 19:56:00 -07:00
Linus Torvalds
36423a5ed5 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, apic: Fix apic=debug boot crash
  x86, hotplug: Serialize CPU hotplug to avoid bringup concurrency issues
  x86-32: Fix dummy trampoline-related inline stubs
  x86-32: Separate 1:1 pagetables from swapper_pg_dir
  x86, cpu: Fix regression in AMD errata checking code
2010-08-20 14:25:08 -07:00
Suresh Siddha
cd7240c0b9 x86, tsc, sched: Recompute cyc2ns_offset's during resume from sleep states
TSC's get reset after suspend/resume (even on cpu's with invariant TSC
which runs at a constant rate across ACPI P-, C- and T-states). And in
some systems BIOS seem to reinit TSC to arbitrary large value (still
sync'd across cpu's) during resume.

This leads to a scenario of scheduler rq->clock (sched_clock_cpu()) less
than rq->age_stamp (introduced in 2.6.32). This leads to a big value
returned by scale_rt_power() and the resulting big group power set by the
update_group_power() is causing improper load balancing between busy and
idle cpu's after suspend/resume.

This resulted in multi-threaded workloads (like kernel-compilation) go
slower after suspend/resume cycle on core i5 laptops.

Fix this by recomputing cyc2ns_offset's during resume, so that
sched_clock() continues from the point where it was left off during
suspend.

Reported-by: Florian Pritz <flo@xssn.at>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: <stable@kernel.org> # [v2.6.32+]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1282262618.2675.24.camel@sbsiddha-MOBL3.sc.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-08-20 14:59:02 +02:00
Daniel Kiper
05e407603e x86, apic: Fix apic=debug boot crash
Fix a boot crash when apic=debug is used and the APIC is
not properly initialized.

This issue appears during Xen Dom0 kernel boot but the
fix is generic and the crash could occur on real hardware
as well.

Signed-off-by: Daniel Kiper <dkiper@net-space.pl>
Cc: xen-devel@lists.xensource.com
Cc: konrad.wilk@oracle.com
Cc: jeremy@goop.org
Cc: <stable@kernel.org> # .35.x, .34.x, .33.x, .32.x
LKML-Reference: <20100819224616.GB9967@router-fw-old.local.net-space.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-08-20 10:18:28 +02:00
Borislav Petkov
d7c53c9e82 x86, hotplug: Serialize CPU hotplug to avoid bringup concurrency issues
When testing cpu hotplug code on 32-bit we kept hitting the "CPU%d:
Stuck ??" message due to multiple cores concurrently accessing the
cpu_callin_mask, among others.

Since these codepaths are not protected from concurrent access due to
the fact that there's no sane reason for making an already complex
code unnecessarily more complex - we hit the issue only when insanely
switching cores off- and online - serialize hotplugging cores on the
sysfs level and be done with it.

[ v2.1: fix !HOTPLUG_CPU build ]

Cc: <stable@kernel.org>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <20100819181029.GC17171@aftab>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-08-19 14:47:43 -07:00
Linus Torvalds
b3ea36b7a2 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:
  kprobes/x86: Fix the return address of multiple kretprobes
  perf tools: Fix build error on read only source.
  perf, x86: Fix Intel-nhm PMU programming errata workaround
2010-08-19 09:06:49 -07:00
KUMANO Syuhei
737480a0d5 kprobes/x86: Fix the return address of multiple kretprobes
Fix the return address of subsequent kretprobes when multiple
kretprobes are set on the same function.

For example:

 # cd /sys/kernel/debug/tracing
 # echo "r:event1 sys_symlink" > kprobe_events
 # echo "r:event2 sys_symlink" >> kprobe_events
 # echo 1 > events/kprobes/enable
 # ln -s /tmp/foo /tmp/bar

(without this patch)

 # cat trace
              ln-897   [000] 20404.133727: event1: (kretprobe_trampoline+0x0/0x4c <- sys_symlink)
              ln-897   [000] 20404.133747: event2: (system_call_fastpath+0x16/0x1b <- sys_symlink)

(with this patch)

 # cat trace
              ln-740   [000] 13799.491076: event1: (system_call_fastpath+0x16/0x1b <- sys_symlink)
              ln-740   [000] 13799.491096: event2: (system_call_fastpath+0x16/0x1b <- sys_symlink)

Signed-off-by: KUMANO Syuhei <kumano.prog@gmail.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
LKML-Reference: <1281853084.3254.11.camel@camp10-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-08-19 12:49:56 +02:00
Joerg Roedel
fd89a13792 x86-32: Separate 1:1 pagetables from swapper_pg_dir
This patch fixes machine crashes which occur when heavily exercising the
CPU hotplug codepaths on a 32-bit kernel. These crashes are caused by
AMD Erratum 383 and result in a fatal machine check exception. Here's
the scenario:

1. On 32-bit, the swapper_pg_dir page table is used as the initial page
table for booting a secondary CPU.

2. To make this work, swapper_pg_dir needs a direct mapping of physical
memory in it (the low mappings). By adding those low, large page (2M)
mappings (PAE kernel), we create the necessary conditions for Erratum
383 to occur.

3. Other CPUs which do not participate in the off- and onlining game may
use swapper_pg_dir while the low mappings are present (when leave_mm is
called). For all steps below, the CPU referred to is a CPU that is using
swapper_pg_dir, and not the CPU which is being onlined.

4. The presence of the low mappings in swapper_pg_dir can result
in TLB entries for addresses below __PAGE_OFFSET to be established
speculatively. These TLB entries are marked global and large.

5. When the CPU with such TLB entry switches to another page table, this
TLB entry remains because it is global.

6. The process then generates an access to an address covered by the
above TLB entry but there is a permission mismatch - the TLB entry
covers a large global page not accessible to userspace.

7. Due to this permission mismatch a new 4kb, user TLB entry gets
established. Further, Erratum 383 provides for a small window of time
where both TLB entries are present. This results in an uncorrectable
machine check exception signalling a TLB multimatch which panics the
machine.

There are two ways to fix this issue:

        1. Always do a global TLB flush when a new cr3 is loaded and the
        old page table was swapper_pg_dir. I consider this a hack hard
        to understand and with performance implications

        2. Do not use swapper_pg_dir to boot secondary CPUs like 64-bit
        does.

This patch implements solution 2. It introduces a trampoline_pg_dir
which has the same layout as swapper_pg_dir with low_mappings. This page
table is used as the initial page table of the booting CPU. Later in the
bringup process, it switches to swapper_pg_dir and does a global TLB
flush. This fixes the crashes in our test cases.

-v2: switch to swapper_pg_dir right after entering start_secondary() so
that we are able to access percpu data which might not be mapped in the
trampoline page table.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
LKML-Reference: <20100816123833.GB28147@aftab>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-08-18 09:17:20 -07:00
Hans Rosenfeld
07a7795ca2 x86, cpu: Fix regression in AMD errata checking code
A bug in the family-model-stepping matching code caused the presence of
errata to go undetected when OSVW was not used. This causes hangs on
some K8 systems because the E400 workaround is not enabled.

Signed-off-by: Hans Rosenfeld <hans.rosenfeld@amd.com>
LKML-Reference: <1282141190-930137-1-git-send-email-hans.rosenfeld@amd.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-08-18 09:16:28 -07:00
Zhang, Yanmin
351af0725e perf, x86: Fix Intel-nhm PMU programming errata workaround
Fix the Errata AAK100/AAP53/BD53 workaround, the officialy documented
workaround we implemented in:

 11164cd: perf, x86: Add Nehelem PMU programming errata workaround

doesn't actually work fully and causes a stuck PMU state
under load and non-functioning perf profiling.

A functional workaround was found by trial & error.

Affects all Nehalem-class Intel PMUs.

Signed-off-by: Zhang Yanmin <yanmin_zhang@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1281073148.2125.63.camel@ymzhang.sh.intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <stable@kernel.org> # .35.x
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-08-18 11:17:39 +02:00
Linus Torvalds
392abeea52 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
  vt,console,kdb: preserve console_blanked while in kdb
  vt: fix regression warnings from KMS merge
  arm,kgdb: fix GDB_MAX_REGS no longer used
  kgdb: add missing __percpu markup in arch/x86/kernel/kgdb.c
  kdb: fix compile error without CONFIG_KALLSYMS
2010-08-17 18:36:19 -07:00
David Howells
d7627467b7 Make do_execve() take a const filename pointer
Make do_execve() take a const filename pointer so that kernel_execve() compiles
correctly on ARM:

arch/arm/kernel/sys_arm.c:88: warning: passing argument 1 of 'do_execve' discards qualifiers from pointer target type

This also requires the argv and envp arguments to be consted twice, once for
the pointer array and once for the strings the array points to.  This is
because do_execve() passes a pointer to the filename (now const) to
copy_strings_kernel().  A simpler alternative would be to cast the filename
pointer in do_execve() when it's passed to copy_strings_kernel().

do_execve() may not change any of the strings it is passed as part of the argv
or envp lists as they are some of them in .rodata, so marking these strings as
const should be fine.

Further kernel_execve() and sys_execve() need to be changed to match.

This has been test built on x86_64, frv, arm and mips.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-17 18:07:43 -07:00
Namhyung Kim
8c8aefce93 kgdb: add missing __percpu markup in arch/x86/kernel/kgdb.c
breakinfo->pev is a pointer to percpu pointer but was missing __percpu markup.
Add it.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-08-16 15:58:30 -05:00
Xiaotian Feng
f45755b834 KVM: fix poison overwritten caused by using wrong xstate size
fpu.state is allocated from task_xstate_cachep, the size of task_xstate_cachep
is xstate_size. xstate_size is set from cpuid instruction, which is often
smaller than sizeof(struct xsave_struct). kvm is using sizeof(struct xsave_struct)
to fill in/out fpu.state.xsave, as what we allocated for fpu.state is
xstate_size, kernel will write out of memory and caused poison/redzone/padding
overwritten warnings.

Signed-off-by: Xiaotian Feng <dfeng@redhat.com>
Reviewed-by: Sheng Yang <sheng@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Sheng Yang <sheng@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-15 14:10:15 +03:00
Len Brown
95ee46aa86 Merge branch 'linus' into release
Conflicts:
	drivers/acpi/debug.c

Signed-off-by: Len Brown <len.brown@intel.com>
2010-08-15 01:06:31 -04:00
Linus Torvalds
c206d44ffd Merge branch 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, UV: Make kdump avoid stack dumps - fix !CONFIG_KEXEC breakage
  x86, UV: Initialize BAU hub map
  x86, UV: Make kdump avoid stack dumps
2010-08-13 18:00:25 -07:00
Linus Torvalds
78b148696d 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] acpi-cpufreq: add missing __percpu markup
2010-08-13 17:59:09 -07:00
David Howells
c788732523 Mark arguments to certain syscalls as being const
Mark arguments to certain system calls as being const where they should be but
aren't.  The list includes:

 (*) The filename arguments of various stat syscalls, execve(), various utimes
     syscalls and some mount syscalls.

 (*) The filename arguments of some syscall helpers relating to the above.

 (*) The buffer argument of various write syscalls.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-13 16:53:13 -07:00
Linus Torvalds
4b17cafaa4 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: (30 commits)
  perf: Add back list_head data types
  perf ui hist browser: Fixup key bindings
  perf ui browser: Add ui_browser__show counterpart: __hide
  perf annotate: Cycle thru sorted lines with samples
  perf ui: Make SPACE work as PGDN in all browsers
  perf annotate: Sort by hottest lines in the TUI
  perf ui: Complete the breakdown of util/newt.c
  perf ui: Move hists browser to util/ui/browsers/
  perf symbols: Ignore mapping symbols on ARM
  perf ui: Move map browser to util/ui/browsers/
  perf ui: Move annotate browser to util/ui/browsers/
  perf ui: Move ui_progress routines to separate file in util/ui/
  perf ui: Move ui_helpline routines to separate file in util/ui/
  perf ui: Shorten ui_browser member names
  perf, x86: P4 PMU -- update nmi irq statistics and unmask lvt entry properly
  perf ui: Start breaking down newt.c into multiple files
  perf tui: Introduce list_head based generic ui_browser refresh routine
  perf probe: Fix memory leaks in add_perf_probe_events
  perf probe: Fix to copy the type for raw parameters
  perf report: Speed up exit path
  ...
2010-08-13 10:39:30 -07:00
Linus Torvalds
36450e9c95 Merge branch 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, UV: Initialize BAU MMRs only on hubs with cpus
  x86, UV: Modularize BAU send and wait
  x86, UV: BAU broadcast to the local hub
  x86, UV: Correct BAU regular message type
  x86, UV: Remove BAU check for stay-busy
  x86, UV: Correct BAU discovery of hubs and sockets
  x86, UV: Correct BAU software acknowledge
  x86, UV: BAU structure rearranging
  x86, UV: Shorten access to BAU statistics structure
  x86, UV: Disable BAU on network congestion
  x86, UV: BAU tunables into a debugfs file
  x86, UV: Calculate BAU destination timeout
2010-08-13 10:38:37 -07:00
Linus Torvalds
c029b55af7 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, asm: Use a lower case name for the end macro in atomic64_386_32.S
  x86, asm: Refactor atomic64_386_32.S to support old binutils and be cleaner
  x86: Document __phys_reloc_hide() usage in __pa_symbol()
  x86, apic: Map the local apic when parsing the MP table.
2010-08-13 10:35:48 -07:00
Namhyung Kim
3f6c4df7e1 [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>
2010-08-13 11:11:49 -04:00