high_width can be easily calculated in a single expression when
making use of __ffs64().
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/4FF71053020000780008E1B5@nat28.tlf.novell.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

With the variable operated on being of "unsigned long" type,
neither ffs() nor fls() are suitable to use on them, as those
truncate their arguments to 32 bits. Using __ffs() and __fls()
respectively at once eliminates the need to subtract 1 from their
results.

Additionally, with the alignment value subsequently used as a
shift count, it must be enforced to be less than BITS_PER_LONG
(and on 64-bit there's no need for it to be any smaller).
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/4FF70D54020000780008E179@nat28.tlf.novell.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

When boot on sun G5+ with 4T mem, see an overflow in mtrr cleanup as below.

*BAD*gran_size: 2G      chunk_size: 2G  num_reg: 10     lose cover RAM:
-18014398505283592M

This is because 1<<31 sign extended. Use an unsigned long constant to
fix it.  Useful for mem larger than or equal to 4T.

-v2: Use 64bit constant instead of explicit type conversion as suggested
by Yinghai. Description updated too.
Signed-off-by: NZhenzhong Duan <zhenzhong.duan@oracle.com>
Link: http://lkml.kernel.org/r/4FC5A77F.6060505@oracle.comSigned-off-by: NH. Peter Anvin <hpa@zytor.com>

Disintegrate asm/system.h for X86.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
cc: x86@kernel.org

Specify the data structures for the 64-bit ioctls with explicit sizing
and padding so that the x32 kernel will correctly use the 64-bit forms
of these ioctls.  Note that these ioctls are bogus in both forms on
both 32 and 64 bits; even on 64 bits the maximum MTRR size is only 44
bits long.

Note that nothing really is supposed to use these ioctls and that the
preferred interface is text strings on /proc/mtrr, or better yet,
nothing at all (use /sys/bus/pci/devices/*/resource*_wc for write
combining; that uses PAT not MTRRs.)
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: H. J. Lu <hjl.tools@gmail.com>
Tested-by: NNitin A. Kamble <nitin.a.kamble@intel.com>
Link: http://lkml.kernel.org/n/tip-vwvnlu3hjmtkwvij4qxtm90l@git.kernel.orgSigned-off-by: NH. Peter Anvin <hpa@zytor.com>

Following is from Notes of section 11.5.3 of Intel processor
manual available at:

  http://www.intel.com/Assets/PDF/manual/325384.pdf

For the Pentium 4 and Intel Xeon processors, after the sequence of
steps given above has been executed, the cache lines containing the
code between the end of the WBINVD instruction and before the
MTRRS have actually been disabled may be retained in the cache
hierarchy. Here, to remove code from the cache completely, a
second WBINVD instruction must be executed after the MTRRs have
been disabled.

This patch provides resolution for that.

Ideally, I will like to make changes only for Pentium 4 and Xeon
processors. But, I am not finding easier way to do it.
And, extra wbinvd() instruction does not hurt much for other
processors.
Signed-off-by: NAjaykumar Hotchandani <ajaykumar.hotchandani@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Link: http://lkml.kernel.org/r/4EBD1CC5.3030008@oracle.comSigned-off-by: NIngo Molnar <mingo@elte.hu>

TAINT_FIRMWARE_WORKAROUND should be set when an MTRR fixup
is done.
Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/1318958650-12447-1-git-send-email-prarit@redhat.comSigned-off-by: NIngo Molnar <mingo@elte.hu>

While removing custom rendezvous code and switching to stop_machine,
commit 192d8857 ("x86, mtrr: use stop_machine APIs for doing MTRR
rendezvous") completely dropped mtrr setting code on !CONFIG_SMP
breaking MTRR settting on UP.

Fix it by removing the incorrect CONFIG_SMP.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NAnders Eriksson <aeriksson@fastmail.fm>
Tested-and-acked-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This code uses PCI_CLASS_REVISION instead of PCI_REVISION_ID, so
it wasn't converted by commit 44c10138 ("PCI: Change all
drivers to use pci_device->revision") before being moved to
arch/x86/...

Do it now at last -- and save one level of indentation...
Signed-off-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/201107012242.08347.sshtylyov@ru.mvista.comSigned-off-by: NIngo Molnar <mingo@elte.hu>

MTRR rendezvous sequence is not implemened using stop_machine() before, as this
gets called both from the process context aswell as the cpu online paths
(where the cpu has not come online and the interrupts are disabled etc).

Now that we have a new stop_machine_from_inactive_cpu() API, use it for
rendezvous during mtrr init of a logical processor that is coming online.

For the rest (runtime MTRR modification, system boot, resume paths), use
stop_machine() to implement the rendezvous sequence. This will consolidate and
cleanup the code.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/20110623182057.076997177@sbsiddha-MOBL3.sc.intel.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

MTRR rendezvous sequence using stop_one_cpu_nowait() can potentially
happen in parallel with another system wide rendezvous using
stop_machine(). This can lead to deadlock (The order in which
works are queued can be different on different cpu's. Some cpu's
will be running the first rendezvous handler and others will be running
the second rendezvous handler. Each set waiting for the other set to join
for the system wide rendezvous, leading to a deadlock).

MTRR rendezvous sequence is not implemented using stop_machine() as this
gets called both from the process context aswell as the cpu online paths
(where the cpu has not come online and the interrupts are disabled etc).
stop_machine() works with only online cpus.

For now, take the stop_machine mutex in the MTRR rendezvous sequence that
gets called from an online cpu (here we are in the process context
and can potentially sleep while taking the mutex). And the MTRR rendezvous
that gets triggered during cpu online doesn't need to take this stop_machine
lock (as the stop_machine() already ensures that there is no cpu hotplug
going on in parallel by doing get_online_cpus())

    TBD: Pursue a cleaner solution of extending the stop_machine()
         infrastructure to handle the case where the calling cpu is
         still not online and use this for MTRR rendezvous sequence.

fixes: https://bugzilla.novell.com/show_bug.cgi?id=672008Reported-by: NVadim Kotelnikov <vadimuzzz@inbox.ru>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/20110623182056.807230326@sbsiddha-MOBL3.sc.intel.com
Cc: stable@kernel.org # 2.6.35+, backport a week or two after this gets more testing in mainline
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

On laptops with core i5/i7, there were reports that after resume
graphics workloads were performing poorly on a specific AP, while
the other cpu's were ok. This was observed on a 32bit kernel
specifically.

Debug showed that the PAT init was not happening on that AP
during resume and hence it contributing to the poor workload
performance on that cpu.

On this system, resume flow looked like this:

1. BP starts the resume sequence and we reinit BP's MTRR's/PAT
   early on using mtrr_bp_restore()

2. Resume sequence brings all AP's online

3. Resume sequence now kicks off the MTRR reinit on all the AP's.

4. For some reason, between point 2 and 3, we moved from BP
   to one of the AP's. My guess is that printk() during resume
   sequence is contributing to this. We don't see similar
   behavior with the 64bit kernel but there is no guarantee that
   at this point the remaining resume sequence (after AP's bringup)
   has to happen on BP.

5. set_mtrr() was assuming that we are still on BP and skipped the
   MTRR/PAT init on that cpu (because of 1 above)

6. But we were on an AP and this led to not reprogramming PAT
   on this cpu leading to bad performance.

Fix this by doing unconditional mtrr_if->set_all() in set_mtrr()
during MTRR/PAT init. This might be unnecessary if we are still
running on BP. But it is of no harm and will guarantee that after
resume, all the cpu's will be in sync with respect to the
MTRR/PAT registers.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1301438292-28370-1-git-send-email-eric@anholt.net>
Signed-off-by: NEric Anholt <eric@anholt.net>
Tested-by: NKeith Packard <keithp@keithp.com>
Cc: stable@kernel.org	[v2.6.32+]
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Some subsystems in the x86 tree need to carry out suspend/resume and
shutdown operations with one CPU on-line and interrupts disabled and
they define sysdev classes and sysdevs or sysdev drivers for this
purpose.  This leads to unnecessarily complicated code and excessive
memory usage, so switch them to using struct syscore_ops objects for
this purpose instead.

Generally, there are three categories of subsystems that use
sysdevs for implementing PM operations: (1) subsystems whose
suspend/resume callbacks ignore their arguments entirely (the
majority), (2) subsystems whose suspend/resume callbacks use their
struct sys_device argument, but don't really need to do that,
because they can be implemented differently in an arguably simpler
way (io_apic.c), and (3) subsystems whose suspend/resume callbacks
use their struct sys_device argument, but the value of that argument
is always the same and could be ignored (microcode_core.c).  In all
of these cases the subsystems in question may be readily converted to
using struct syscore_ops objects for power management and shutdown.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NIngo Molnar <mingo@elte.hu>

They were generated by 'codespell' and then manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: trivial@kernel.org
LKML-Reference: <1300389856-1099-3-git-send-email-lucas.demarchi@profusion.mobi>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Markus Kohn ran into a hard hang regression on an acer aspire
1310, when acpi is enabled. git bisect showed the following
commit as the bad one that introduced the boot regression.

	commit d0af9eed
	Author: Suresh Siddha <suresh.b.siddha@intel.com>
	Date:   Wed Aug 19 18:05:36 2009 -0700

	    x86, pat/mtrr: Rendezvous all the cpus for MTRR/PAT init

Because of the UP configuration of that platform,
native_smp_prepare_cpus() bailed out (in smp_sanity_check())
before doing the set_mtrr_aps_delayed_init()

Further down the boot path, native_smp_cpus_done() will call the
delayed MTRR initialization for the AP's (mtrr_aps_init()) with
mtrr_aps_delayed_init not set. This resulted in the boot
processor reprogramming its MTRR's to the values seen during the
start of the OS boot. While this is not needed ideally, this
shouldn't have caused any side-effects. This is because the
reprogramming of MTRR's (set_mtrr_state() that gets called via
set_mtrr()) will check if the live register contents are
different from what is being asked to write and will do the actual
write only if they are different.

BP's mtrr state is read during the start of the OS boot and
typically nothing would have changed when we ask to reprogram it
on BP again because of the above scenario on an UP platform. So
on a normal UP platform no reprogramming of BP MTRR MSR's
happens and all is well.

However, on this platform, bios seems to be modifying the fixed
mtrr range registers between the start of OS boot and when we
double check the live registers for reprogramming BP MTRR
registers. And as the live registers are modified, we end up
reprogramming the MTRR's to the state seen during the start of
the OS boot.

During ACPI initialization, something in the bios (probably smi
handler?) don't like this fact and results in a hard lockup.

We didn't see this boot hang issue on this platform before the
commit d0af9eed, because only
the AP's (if any) will program its MTRR's to the value that BP
had at the start of the OS boot.

Fix this issue by checking mtrr_aps_delayed_init before
continuing further in the mtrr_aps_init(). Now, only AP's (if
any) will program its MTRR's to the BP values during boot.

Addresses https://bugzilla.novell.com/show_bug.cgi?id=623393

  [ By the way, this behavior of the bios modifying MTRR's after the start
    of the OS boot is not common and the kernel is not prepared to
    handle this situation well. Irrespective of this issue, during
    suspend/resume, linux kernel will try to reprogram the BP's MTRR values
    to the values seen during the start of the OS boot. So suspend/resume might
    be already broken on this platform for all linux kernel versions. ]
Reported-and-bisected-by: NMarkus Kohn <jabber@gmx.org>
Tested-by: NMarkus Kohn <jabber@gmx.org>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: Thomas Renninger <trenn@novell.com>
Cc: Rafael Wysocki <rjw@novell.com>
Cc: Venkatesh Pallipadi <venki@google.com>
Cc: stable@kernel.org # [v2.6.32+]
LKML-Reference: <1296694975.4418.402.camel@sbsiddha-MOBL3.sc.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Instead of adapting the CPU family check in amd_special_default_mtrr()
for each new CPU family assume that all new AMD CPUs support the
necessary bits in SYS_CFG MSR.

Tom2Enabled is architectural (defined in APM Vol.2).
Tom2ForceMemTypeWB is defined in all BKDGs starting with K8 NPT.
In pre K8-NPT BKDG this bit is reserved (read as zero).

W/o this adaption Linux would unnecessarily complain about bad MTRR
settings on every new AMD CPU family, e.g.

[    0.000000] WARNING: BIOS bug: CPU MTRRs don't cover all of memory, losing 4863MB of RAM.

Cc: stable@kernel.org # .32.x, .35.x
Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
LKML-Reference: <20100930123235.GB20545@loge.amd.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

mtrr_type_lookup [start:end] looked up the resultant MTRR type for that
range, based on fixed and all variable MTRR ranges. It did check for multiple
MTRR var ranges overlapping [start:end] and returned the net type.

However, if the [start:end] range spanned across any var MTRR range,
mtrr_type_lookup would return an error return of 0xFE. This was based on
typical usage of mtrr_type_lookup in PAT mapping, where region being
mapped would not normally span across MTRR ranges and also trying
to keep the code simple.

Mark recently reported the problem with this limitation. When there are
two continguous MTRR's of type "writeback" and if there is a memory mapping
over a region starting in one MTRR range and ending in another MTRR range,
such mapping will fallback to "uncached" due to the above limitation.

Change below adds support for such lookups spanning multiple MTRR ranges.
We now have a wrapper mtrr_type_lookup that dynamically splits such a region
into smaller chunks that fit within one MTRR range and does a
__mtrr_type_lookup on it and combine the results later.
Reported-by: NMark Langsdorf <mark.langsdorf@amd.com>
Signed-off-by: NVenkatesh Pallipadi <venki@google.com>
LKML-Reference: <1284159350-19841-3-git-send-email-venki@google.com>
Reviewed-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Move the MTRR type overlap check into a new function. No functional change in
this patch. Just making it easier to add multiple region overlap check in
the following patch.
Signed-off-by: NVenkatesh Pallipadi <venki@google.com>
LKML-Reference: <1284159350-19841-2-git-send-email-venki@google.com>
Reviewed-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Use the stop machine context rather than IPI's to rendezvous all the cpus for
MTRR initialization that happens during cpu bringup or for MTRR modifications
during runtime.

This avoids deadlock scenario (reported by Prarit) like:

cpu A holds a read_lock (tasklist_lock for example) with irqs enabled
cpu B waits for the same lock with irqs disabled using write_lock_irq
cpu C doing set_mtrr() (during AP bringup for example), which will try to
rendezvous all the cpus using IPI's

This will result in C and A come to the rendezvous point and waiting
for B. B is stuck forever waiting for the lock and thus not
reaching the rendezvous point.

Using stop cpu (run in the process context of per cpu based keventd) to do
this rendezvous, avoids this deadlock scenario.

Also make sure all the cpu's are in the rendezvous handler before we proceed
with the local_irq_save() on each cpu. This lock step disabling irqs on all
the cpus will avoid other deadlock scenarios (for example involving
with the blocking smp_call_function's etc).

   [ This problem is very old. Marking -stable only for 2.6.35 as the
     stop_one_cpu_nowait() API is present only in 2.6.35. Any older
     kernel interested in this fix need to do some more work in backporting
     this patch. ]
Reported-by: NPrarit Bhargava <prarit@redhat.com>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1280515602.2682.10.camel@sbsiddha-MOBL3.sc.intel.com>
Acked-by: NPrarit Bhargava <prarit@redhat.com>
Cc: stable@kernel.org	[2.6.35]
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Just some dead code, no real bugs.

Found by gcc 4.6 -Wall
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
LKML-Reference: <201007202219.o6KMJnQ0021072@imap1.linux-foundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Also needed if pr_<level> becomes a bit more space efficient.
Signed-off-by: NJoe Perches <joe@perches.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
LKML-Reference: <1277768808.29157.280.camel@Joe-Laptop.home>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

Fix missing kernel-doc notation in mtrr/main.c:

Warning(arch/x86/kernel/cpu/mtrr/main.c:152): No description found for parameter 'info'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Fixes bugzilla: http://bugzilla.kernel.org/show_bug.cgi?id=12558
Fixes bugzilla: http://bugzilla.kernel.org/show_bug.cgi?id=12317

(and if this really needed to be a warn you'd be responding to the bugs left
in bugzilla from it...)
Signed-off-by: NAlan Cox <alan@linux.intel.com>
LKML-Reference: <20100208100239.2568.2940.stgit@localhost.localdomain>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

So make interface more consistent with early_res.
Later we can share some code with early_res.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-10-git-send-email-yinghai@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

We have almost the same code for mtrr cleanup and amd_bus checkup, and
this code  will also be used in replacing bootmem with early_res,
so try to move them together and reuse it from different parts.

Also rename update_range to subtract_range as that is what the
function is actually doing.

-v2: update comments as Christoph requested
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-4-git-send-email-yinghai@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The last reference to the helpers in
<arch/x86/kernel/cpu/mtrr/state.c> went away with
9a6b344e leaving unused code.
Remove it.
Signed-off-by: NBorislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <20100204085128.GA513@liondog.tnic>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This is part of the ops structure constification
effort started by Arjan van de Ven et al.

Benefits of this constification:

 * prevents modification of data that is shared
   (referenced) by many other structure instances
   at runtime

 * detects/prevents accidental (but not intentional)
   modification attempts on archs that enforce
   read-only kernel data at runtime

 * potentially better optimized code as the compiler
   can assume that the const data cannot be changed

 * the compiler/linker move const data into .rodata
   and therefore exclude them from false sharing
Signed-off-by: NEmese Revfy <re.emese@gmail.com>
LKML-Reference: <4B65D712.3080804@gmail.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Makes use of skip_spaces() defined in lib/string.c for removing leading
spaces from strings all over the tree.

It decreases lib.a code size by 47 bytes and reuses the function tree-wide:
   text    data     bss     dec     hex filename
  64688     584     592   65864   10148 (TOTALS-BEFORE)
  64641     584     592   65817   10119 (TOTALS-AFTER)

Also, while at it, if we see (*str && isspace(*str)), we can be sure to
remove the first condition (*str) as the second one (isspace(*str)) also
evaluates to 0 whenever *str == 0, making it redundant. In other words,
"a char equals zero is never a space".

Julia Lawall tried the semantic patch (http://coccinelle.lip6.fr) below,
and found occurrences of this pattern on 3 more files:
    drivers/leds/led-class.c
    drivers/leds/ledtrig-timer.c
    drivers/video/output.c

@@
expression str;
@@

( // ignore skip_spaces cases
while (*str &&  isspace(*str)) { \(str++;\|++str;\) }
|
- *str &&
isspace(*str)
)
Signed-off-by: NAndré Goddard Rosa <andre.goddard@gmail.com>
Cc: Julia Lawall <julia@diku.dk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Neil Brown <neilb@suse.de>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: David Howells <dhowells@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In some cases we can coalesce MTRR entries after cleanup; this may
allow us to have more entries.  As such, introduce clean_sort_range to
to sort and coaelsce the MTRR entries.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4B0BB9A3.5020908@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The current MTRR code treats WP as a form of UC.  This really isn't
desirable behaviour, except possibly in the case of severe MTRR
shortage.  Disable this, to allow legitimate uses of WP to remain
unmolested.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>

Trivial typo.
Signed-off-by: NDave Jones <davej@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The current bound checks for copy_from_user in the MTRR driver are
not as obvious as they could be, and gcc agrees with that.

This patch simplifies the boundary checks to the point that gcc can
now prove to itself that the copy_from_user() is never going past
its bounds.
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <20090926205150.30797709@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Perhaps this is a more readable/standard form.
Signed-off-by: NJoe Perches <joe@perches.com>
LKML-Reference: <1252945687.3937.14.camel@Joe-Laptop.home>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

mtr_aps_delayed_init was declared u32 and made global, but it only
ever takes boolean values and is only ever used in
arch/x86/kernel/cpu/mtrr/main.c.  Declare it "static bool" and remove
external references.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>

SDM Vol 3a section titled "MTRR considerations in MP systems" specifies
the need for synchronizing the logical cpu's while initializing/updating
MTRR.

Currently Linux kernel does the synchronization of all cpu's only when
a single MTRR register is programmed/updated. During an AP online
(during boot/cpu-online/resume)  where we initialize all the MTRR/PAT registers,
we don't follow this synchronization algorithm.

This can lead to scenarios where during a dynamic cpu online, that logical cpu
is initializing MTRR/PAT with cache disabled (cr0.cd=1) etc while other logical
HT sibling continue to run (also with cache disabled because of cr0.cd=1
on its sibling).

Starting from Westmere, VMX transitions with cr0.cd=1 don't work properly
(because of some VMX performance optimizations) and the above scenario
(with one logical cpu doing VMX activity and another logical cpu coming online)
can result in system crash.

Fix the MTRR initialization by doing rendezvous of all the cpus. During
boot and resume, we delay the MTRR/PAT init for APs till all the
logical cpu's come online and the rendezvous process at the end of AP's bringup,
will initialize the MTRR/PAT for all AP's.

For dynamic single cpu online, we synchronize all the logical cpus and
do the MTRR/PAT init on the AP that is coming online.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Yinghai noticed that i defined BIOS_BUG_MSG but added no
usage for it. The usage is to clean up this turd in generic.c:

			printk(KERN_WARNING "WARNING: BIOS bug: VAR MTRR %d "
				"contains strange UC entry under 1M, check "
				"with your system vendor!\n", i);

Breaking printk lines in the middle looks ugly, is hard to read
and breaks 'git grep'. Use the BIOS_BUG_MSG instead.

Also complete the moving of structure definitions and variables
to the top of the file.
Reported-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <20090703164225.GA21447@elte.hu>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Fix following trivial style problems:

  ERROR: trailing whitespace X 25
  WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>
  WARNING: Use #include <linux/kvm_para.h> instead of <asm/kvm_para.h>
  ERROR: do not initialise externals to 0 or NULL X 2
  ERROR: "foo * bar" should be "foo *bar" X 5
  ERROR: do not use assignment in if condition X 2
  WARNING: line over 80 characters X 8
  ERROR: return is not a function, parentheses are not required
  WARNING: braces {} are not necessary for any arm of this statement
  ERROR: space required before the open parenthesis '(' X 2
  ERROR: open brace '{' following function declarations go on the next line
  ERROR: space required after that ',' (ctx:VxV) X 8
  ERROR: space required before the open parenthesis '(' X 3
  ERROR: else should follow close brace '}'
  WARNING: space prohibited between function name and open parenthesis '('
  WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable X 2

Also use pr_debug and pr_warning where possible.

total: 50 errors, 14 warnings

arch/x86/kernel/cpu/mtrr/main.o:

   text	   data	    bss	    dec	    hex	filename
   3668	    116	   4156	   7940	   1f04	main.o.before
   3668	    116	   4156	   7940	   1f04	main.o.after

md5:
   e01af2fd28deef77c8d01e71acfbd365  main.o.before.asm
   e01af2fd28deef77c8d01e71acfbd365  main.o.after.asm
Suggested-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20090703164225.GA21447@elte.hu>
Cc: Avi Kivity <avi@redhat.com> # Avi, please have a look at the kvm_para.h bit
[ More cleanups ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Fix:

  WARNING: Use #include <linux/io.h> instead of <asm/io.h>
  WARNING: line over 80 characters X 4

arch/x86/kernel/cpu/mtrr/state.o:

   text	   data	    bss	    dec	    hex	filename
    864	      0	      0	    864	    360	state.o.before
    864	      0	      0	    864	    360	state.o.after

md5:
   c5c4364b9aeac74d70111e1e49667a2c  state.o.before.asm
   c5c4364b9aeac74d70111e1e49667a2c  state.o.after.asm
Suggested-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20090703164225.GA21447@elte.hu>
[ More cleanups ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>