Commit Graph

17 Commits

Author SHA1 Message Date
Jason Wang 9df56f19a5 x86: Correctly detect hypervisor
We try to handle the hypervisor compatibility mode by detecting hypervisor
through a specific order. This is not robust, since hypervisors may implement
each others features.

This patch tries to handle this situation by always choosing the last one in the
CPUID leaves. This is done by letting .detect() return a priority instead of
true/false and just re-using the CPUID leaf where the signature were found as
the priority (or 1 if it was found by DMI). Then we can just pick hypervisor who
has the highest priority. Other sophisticated detection method could also be
implemented on top.

Suggested by H. Peter Anvin and Paolo Bonzini.

Acked-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Doug Covelli <dcovelli@vmware.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dan Hecht <dhecht@vmware.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: http://lkml.kernel.org/r/1374742475-2485-4-git-send-email-jasowang@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-08-05 06:35:33 -07:00
Paul Gortmaker 148f9bb877 x86: delete __cpuinit usage from all x86 files
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit  -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings.  In any case, they are temporary and harmless.

This removes all the arch/x86 uses of the __cpuinit macros from
all C files.  x86 only had the one __CPUINIT used in assembly files,
and it wasn't paired off with a .previous or a __FINIT, so we can
delete it directly w/o any corresponding additional change there.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-14 19:36:56 -04:00
Alok N Kataria 4cca6ea04d x86/apic: Allow x2apic without IR on VMware platform
This patch updates x2apic initializaition code to allow x2apic
on VMware platform even without interrupt remapping support.
The hypervisor_x2apic_available hook was added in x2apic
initialization code and used by KVM and XEN, before this.
I have also cleaned up that code to export this hook through the
hypervisor_x86 structure.

Compile tested for KVM and XEN configs, this patch doesn't have
any functional effect on those two platforms.

On VMware platform, verified that x2apic is used in physical
mode on products that support this.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
Reviewed-by: Doug Covelli <dcovelli@vmware.com>
Reviewed-by: Dan Hecht <dhecht@vmware.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Avi Kivity <avi@redhat.com>
Link: http://lkml.kernel.org/r/1358466282.423.60.camel@akataria-dtop.eng.vmware.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-01-24 13:11:18 +01:00
Lucas De Marchi 0d2eb44f63 x86: Fix common misspellings
They were generated by 'codespell' and then manually reviewed.

Signed-off-by: Lucas 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: Ingo Molnar <mingo@elte.hu>
2011-03-18 10:39:30 +01:00
Alok Kataria 9f242dc10e x86, vmware: Preset lpj values when on VMware.
When running on VMware's platform, we have seen situations where
the AP's try to calibrate the lpj values and fail to get good calibration
runs becasue of timing issues. As a result delays don't work correctly
on all cpus.

The solutions is to set preset_lpj value based on the current tsc frequency
value. This is similar to what KVM does as well.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
LKML-Reference: <1280790637.14933.29.camel@ank32.eng.vmware.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-08-02 17:16:30 -07:00
H. Peter Anvin 96f6e775b5 x86, hypervisor: Export the x86_hyper* symbols
Export x86_hyper and the related specific structures, allowing for
hypervisor identification by modules.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Greg KH <greg@kroah.com>
Cc: Hank Janssen <hjanssen@microsoft.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Ky Srinivasan <ksrinivasan@novell.com>
Cc: Dmitry Torokhov <dtor@vmware.com>
LKML-Reference: <4BE49778.6060800@zytor.com>
2010-05-09 01:10:34 -07:00
H. Peter Anvin d7be0ce6af Merge commit 'v2.6.34-rc6' into x86/cpu 2010-05-08 14:59:58 -07:00
H. Peter Anvin e08cae4181 x86: Clean up the hypervisor layer
Clean up the hypervisor layer and the hypervisor drivers, using an ops
structure instead of an enumeration with if statements.

The identity of the hypervisor, if needed, can be tested by testing
the pointer value in x86_hyper.

The MS-HyperV private state is moved into a normal global variable
(it's per-system state, not per-CPU state).  Being a normal bss
variable, it will be left at all zero on non-HyperV platforms, and so
can generally be tested for HyperV-specific features without
additional qualification.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Greg KH <greg@kroah.com>
Cc: Hank Janssen <hjanssen@microsoft.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Ky Srinivasan <ksrinivasan@novell.com>
LKML-Reference: <4BE49778.6060800@zytor.com>
2010-05-07 17:13:04 -07:00
Dmitry Torokhov 453dc65931 VMware Balloon driver
This is a standalone version of VMware Balloon driver.  Ballooning is a
technique that allows hypervisor dynamically limit the amount of memory
available to the guest (with guest cooperation).  In the overcommit
scenario, when hypervisor set detects that it needs to shuffle some
memory, it instructs the driver to allocate certain number of pages, and
the underlying memory gets returned to the hypervisor.  Later hypervisor
may return memory to the guest by reattaching memory to the pageframes and
instructing the driver to "deflate" balloon.

We are submitting a standalone driver because KVM maintainer (Avi Kivity)
expressed opinion (rightly) that our transport does not fit well into
virtqueue paradigm and thus it does not make much sense to integrate with
virtio.

There were also some concerns whether current ballooning technique is the
right thing.  If there appears a better framework to achieve this we are
prepared to evaluate and switch to using it, but in the meantime we'd like
to get this driver upstream.

We want to get the driver accepted in distributions so that users do not
have to deal with an out-of-tree module and many distributions have
"upstream first" requirement.

The driver has been shipping for a number of years and users running on
VMware platform will have it installed as part of VMware Tools even if it
will not come from a distribution, thus there should not be additional
risk in pulling the driver into mainline.  The driver will only activate
if host is VMware so everyone else should not be affected at all.

Signed-off-by: Dmitry Torokhov <dtor@vmware.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-04-24 11:31:26 -07:00
Alok Kataria 6399c08745 x86: Print the hypervisor returned tsc_khz during boot
On an AMD-64 system the processor frequency that is printed during
system boot, may be different than the tsc frequency that was
returned by the hypervisor, due to the value returned from
calibrate_cpu.

For debugging timekeeping or other related issues it might be
better to get the tsc_khz value returned by the hypervisor.

The patch below now prints the tsc frequency that the VMware
hypervisor returned.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
LKML-Reference: <1252095219.12518.13.camel@ank32.eng.vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-20 20:25:36 +02:00
Thomas Gleixner 2d826404f0 x86: Move tsc_calibration to x86_init_ops
TSC calibration is modified by the vmware hypervisor and paravirt by
separate means. Moorestown wants to add its own calibration routine as
well. So make calibrate_tsc a proper x86_init_ops function and
override it by paravirt or by the early setup of the vmware
hypervisor.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:47 +02:00
Alan Cox 8bdbd962ec x86/cpu: Clean up various files a bit
No code changes except printk levels (although some of the K6
mtrr code might be clearer if there were a few as would
splitting out some of the intel cache code).

Signed-off-by: Alan Cox <alan@linux.intel.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-11 11:24:09 +02:00
Hannes Eder c450d7805b x86: vmware - fix sparse warnings
Impact: fix sparse build warning

Fix the following sparse warnings:

arch/x86/kernel/cpu/vmware.c:69:5: warning: symbol 'vmware_platform'
was not declared. Should it be static?
arch/x86/kernel/cpu/vmware.c:89:15: warning: symbol
'vmware_get_tsc_khz' was not declared. Should it be static?
arch/x86/kernel/cpu/vmware.c:107:16: warning: symbol
'vmware_set_feature_bits' was not declared. Should it be static?

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Cc: "Alok N Kataria" <akataria@vmware.com>
Cc: "Dan Hecht" <dhecht@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-23 11:02:36 +01:00
Alok Kataria fd8cd7e191 x86: vmware: look for DMI string in the product serial key
Impact: Should permit VMware detection on older platforms where the
vendor is changed.  Could theoretically cause a regression if some
weird serial number scheme contains the string "VMware" by pure
chance.  Seems unlikely, especially with the mixed case.

In some user configured cases, VMware may choose not to put a VMware specific
DMI string, but the product serial key is always there and is VMware specific.
Add a interface to check the serial key, when checking for VMware in the DMI
information.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-11-04 13:59:00 -08:00
Alok Kataria 6bdbfe9991 x86: VMware: Fix vmware_get_tsc code
Impact: Fix possible failure to calibrate the TSC on Vmware near 4 GHz

The current version of the code to get the tsc frequency from
the VMware hypervisor, will be broken on processor with frequency
(4G-1) HZ, because on such processors eax will have UINT_MAX
and that would be legitimate.
We instead check that EBX did change to decide if we were able to
read the frequency from the hypervisor.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-11-03 11:35:57 -08:00
Alok Kataria eca0cd028b x86: Add a synthetic TSC_RELIABLE feature bit.
Impact: Changes timebase calibration on Vmware.

Use the synthetic TSC_RELIABLE bit to workaround virtualization anomalies.

Virtual TSCs can be kept nearly in sync, but because the virtual TSC
offset is set by software, it's not perfect.  So, the TSC
synchronization test can fail. Even then the TSC can be used as a
clocksource since the VMware platform exports a reliable TSC to the
guest for timekeeping purposes. Use this bit to check if we need to
skip the TSC sync checks.

Along with this also set the CONSTANT_TSC bit when on VMware, since we
still want to use TSC as clocksource on VM running over hardware which
has unsynchronized TSC's (opteron's), since the hypervisor will take
care of providing consistent TSC to the guest.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
Signed-off-by: Dan Hecht <dhecht@vmware.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-11-01 18:58:01 -07:00
Alok Kataria 88b094fb8d x86: Hypervisor detection and get tsc_freq from hypervisor
Impact: Changes timebase calibration on Vmware.

v3->v2 : Abstract the hypervisor detection and feature (tsc_freq) request
	 behind a hypervisor.c file
v2->v1 : Add a x86_hyper_vendor field to the cpuinfo_x86 structure.
	 This avoids multiple calls to the hypervisor detection function.

This patch adds function to detect if we are running under VMware.
The current way to check if we are on VMware is following,
#  check if "hypervisor present bit" is set, if so read the 0x40000000
   cpuid leaf and check for "VMwareVMware" signature.
#  if the above fails, check the DMI vendors name for "VMware" string
   if we find one we query the VMware hypervisor port to check if we are
   under VMware.

The DMI + "VMware hypervisor port check" is needed for older VMware products,
which don't implement the hypervisor signature cpuid leaf.
Also note that since we are checking for the DMI signature the hypervisor
port should never be accessed on native hardware.

This patch also adds a hypervisor_get_tsc_freq function, instead of
calibrating the frequency which can be error prone in virtualized
environment, we ask the hypervisor for it. We get the frequency from
the hypervisor by accessing the hypervisor port if we are running on VMware.
Other hypervisors too can add code to the generic routine to get frequency on
their platform.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
Signed-off-by: Dan Hecht <dhecht@vmware.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-11-01 18:57:08 -07:00