Commit Graph

321 Commits

Author SHA1 Message Date
Linus Torvalds b2e09f633a Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull more scheduler updates from Ingo Molnar:
 "Second round of scheduler changes:
   - try-to-wakeup and IPI reduction speedups, from Andy Lutomirski
   - continued power scheduling cleanups and refactorings, from Nicolas
     Pitre
   - misc fixes and enhancements"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/deadline: Delete extraneous extern for to_ratio()
  sched/idle: Optimize try-to-wake-up IPI
  sched/idle: Simplify wake_up_idle_cpu()
  sched/idle: Clear polling before descheduling the idle thread
  sched, trace: Add a tracepoint for IPI-less remote wakeups
  cpuidle: Set polling in poll_idle
  sched: Remove redundant assignment to "rt_rq" in update_curr_rt(...)
  sched: Rename capacity related flags
  sched: Final power vs. capacity cleanups
  sched: Remove remaining dubious usage of "power"
  sched: Let 'struct sched_group_power' care about CPU capacity
  sched/fair: Disambiguate existing/remaining "capacity" usage
  sched/fair: Change "has_capacity" to "has_free_capacity"
  sched/fair: Remove "power" from 'struct numa_stats'
  sched: Fix signedness bug in yield_to()
  sched/fair: Use time_after() in record_wakee()
  sched/balancing: Reduce the rate of needless idle load balancing
  sched/fair: Fix unlocked reads of some cfs_b->quota/period
2014-06-12 19:42:15 -07:00
Dan Carpenter fa93384f40 sched: Fix signedness bug in yield_to()
yield_to() is supposed to return -ESRCH if there is no task to
yield to, but because the type is bool that is the same as returning
true.

The only place I see which cares is kvm_vcpu_on_spin().

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Raghavendra <raghavendra.kt@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org
Link: http://lkml.kernel.org/r/20140523102042.GA7267@mwanda
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-05 11:52:13 +02:00
Christian Borntraeger 719d93cd5f kvm/irqchip: Speed up KVM_SET_GSI_ROUTING
When starting lots of dataplane devices the bootup takes very long on
Christian's s390 with irqfd patches. With larger setups he is even
able to trigger some timeouts in some components.  Turns out that the
KVM_SET_GSI_ROUTING ioctl takes very long (strace claims up to 0.1 sec)
when having multiple CPUs.  This is caused by the  synchronize_rcu and
the HZ=100 of s390.  By changing the code to use a private srcu we can
speed things up.  This patch reduces the boot time till mounting root
from 8 to 2 seconds on my s390 guest with 100 disks.

Uses of hlist_for_each_entry_rcu, hlist_add_head_rcu, hlist_del_init_rcu
are fine because they do not have lockdep checks (hlist_for_each_entry_rcu
uses rcu_dereference_raw rather than rcu_dereference, and write-sides
do not do rcu lockdep at all).

Note that we're hardly relying on the "sleepable" part of srcu.  We just
want SRCU's faster detection of grace periods.

Testing was done by Andrew Theurer using netperf tests STREAM, MAERTS
and RR.  The difference between results "before" and "after" the patch
has mean -0.2% and standard deviation 0.6%.  Using a paired t-test on the
data points says that there is a 2.5% probability that the patch is the
cause of the performance difference (rather than a random fluctuation).

(Restricting the t-test to RR, which is the most likely to be affected,
changes the numbers to respectively -0.3% mean, 0.7% stdev, and 8%
probability that the numbers actually say something about the patch.
The probability increases mostly because there are fewer data points).

Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> # s390
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-05-05 16:29:11 +02:00
David Hildenbrand 8ad3575517 KVM: s390: enable IBS for single running VCPUs
This patch enables the IBS facility when a single VCPU is running.
The facility is dynamically turned on/off as soon as other VCPUs
enter/leave the stopped state.

When this facility is operating, some instructions can be executed
faster for single-cpu guests.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2014-04-29 15:01:54 +02:00
Xiao Guangrong a086f6a1eb Revert "KVM: Simplify kvm->tlbs_dirty handling"
This reverts commit 5befdc385d.

Since we will allow flush tlb out of mmu-lock in the later
patch

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2014-04-23 17:49:48 -03:00
Marcelo Tosatti 63b5cf04f4 Lazy storage key handling
-------------------------
 Linux does not use the ACC and F bits of the storage key. Newer Linux
 versions also do not use the storage keys for dirty and reference
 tracking. We can optimize the guest handling for those guests for faults
 as well as page-in and page-out by simply not caring about the guest
 visible storage key. We trap guest storage key instruction to enable
 those keys only on demand.
 
 Migration bitmap
 
 Until now s390 never provided a proper dirty bitmap.  Let's provide a
 proper migration bitmap for s390. We also change the user dirty tracking
 to a fault based mechanism. This makes the host completely independent
 from the storage keys. Long term this will allow us to back guest memory
 with large pages.
 
 per-VM device attributes
 ------------------------
 To avoid the introduction of new ioctls, let's provide the
 attribute semanantic also on the VM-"device".
 
 Userspace controlled CMMA
 -------------------------
 The CMMA assist is changed from "always on" to "on if requested" via
 per-VM device attributes. In addition a callback to reset all usage
 states is provided.
 
 Proper guest DAT handling for intercepts
 ----------------------------------------
 While instructions handled by SIE take care of all addressing aspects,
 KVM/s390 currently does not care about guest address translation of
 intercepts. This worked out fine, because
 - the s390 Linux kernel has a 1:1 mapping between kernel virtual<->real
  for all pages up to memory size
 - intercepts happen only for a small amount of cases
 - all of these intercepts happen to be in the kernel text for current
   distros
 
 Of course we need to be better for other intercepts, kernel modules etc.
 We provide the infrastructure and rework all in-kernel intercepts to work
 on logical addresses (paging etc) instead of real ones. The code has
 been running internally for several months now, so it is time for going
 public.
 
 GDB support
 -----------
 We provide breakpoints, single stepping and watchpoints.
 
 Fixes/Cleanups
 --------------
 - Improve program check delivery
 - Factor out the handling of transactional memory  on program checks
 - Use the existing define __LC_PGM_TDB
 - Several cleanups in the lowcore structure
 - Documentation
 
 NOTES
 -----
 - All patches touching base s390 are either ACKed or written by the s390
   maintainers
 - One base KVM patch "KVM: add kvm_is_error_gpa() helper"
 - One patch introduces the notion of VM device attributes
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.11 (GNU/Linux)
 
 iQIcBAABAgAGBQJTVlHZAAoJEBF7vIC1phx8REgP/1P0EUzfBpoS53z1v60n2uLT
 lW79LY9Op4/ZacEgHtU9LzmGa88X0arDsIpBZQsTNLF77AGFcMCCV3X2il/lQrRG
 KSE+ycKLoFjCcES442DwF4gHoGldD+KL/+5LPWSQZtvb9dDpHDft9aeMRBbpUL0Q
 M2kKQDlmJ2XqQu3D5PwSHgVRByHiHOzmTe2ejSSbdppkwBpaiqSBBBk0jVYDW9Jh
 eqUnBcrrYW2p+QS37ELM6hOkfDXN/vXoHBQeyca19TuZVCPNA7HeJaPc2mJ/GZk9
 wrNWEmY3f/lY0lk0zMwBwsDOS5K7jbtvXzcex6m+NsIqQuOvKsmPBy1BWb/axcK5
 uZq/JGFC0fxsFU+7ImtvQrJ/DMHnVuvSKF4WUVle2GdMlDIqkguwX27WwHSiH4/r
 Au02KlVIMUZdLAEUrw/W/S4MPLeZYoGfetHGCOmSaP2qGc97BVFedZaqekDlUgMw
 3gIoQmSIBcfrgF4k9N4nLjdhAX2S4gkviwF3pTlIkecNfa7RcI3Xk7U9mVPmIhL4
 IquVqjdXZH4m0e4gViBMtQ0IPwGt1qFlV6Wv3O9MExhfi7VQ8M8TMYNhEvtGpY75
 cuZwZYGM4FqszDAy9hbk0avTLqCxqlTiBKi3tHoQMappQmsJPrIdxIpev3MZPHCp
 vZMkbzhM9l3eefNJVw66
 =jxBp
 -----END PGP SIGNATURE-----

Merge tag 'kvm-s390-20140422' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into queue

Lazy storage key handling
-------------------------
Linux does not use the ACC and F bits of the storage key. Newer Linux
versions also do not use the storage keys for dirty and reference
tracking. We can optimize the guest handling for those guests for faults
as well as page-in and page-out by simply not caring about the guest
visible storage key. We trap guest storage key instruction to enable
those keys only on demand.

Migration bitmap

Until now s390 never provided a proper dirty bitmap.  Let's provide a
proper migration bitmap for s390. We also change the user dirty tracking
to a fault based mechanism. This makes the host completely independent
from the storage keys. Long term this will allow us to back guest memory
with large pages.

per-VM device attributes
------------------------
To avoid the introduction of new ioctls, let's provide the
attribute semanantic also on the VM-"device".

Userspace controlled CMMA
-------------------------
The CMMA assist is changed from "always on" to "on if requested" via
per-VM device attributes. In addition a callback to reset all usage
states is provided.

Proper guest DAT handling for intercepts
----------------------------------------
While instructions handled by SIE take care of all addressing aspects,
KVM/s390 currently does not care about guest address translation of
intercepts. This worked out fine, because
- the s390 Linux kernel has a 1:1 mapping between kernel virtual<->real
 for all pages up to memory size
- intercepts happen only for a small amount of cases
- all of these intercepts happen to be in the kernel text for current
  distros

Of course we need to be better for other intercepts, kernel modules etc.
We provide the infrastructure and rework all in-kernel intercepts to work
on logical addresses (paging etc) instead of real ones. The code has
been running internally for several months now, so it is time for going
public.

GDB support
-----------
We provide breakpoints, single stepping and watchpoints.

Fixes/Cleanups
--------------
- Improve program check delivery
- Factor out the handling of transactional memory  on program checks
- Use the existing define __LC_PGM_TDB
- Several cleanups in the lowcore structure
- Documentation

NOTES
-----
- All patches touching base s390 are either ACKed or written by the s390
  maintainers
- One base KVM patch "KVM: add kvm_is_error_gpa() helper"
- One patch introduces the notion of VM device attributes

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

Conflicts:
	include/uapi/linux/kvm.h
2014-04-22 10:51:06 -03:00
Heiko Carstens dfeec843fb KVM: add kvm_is_error_gpa() helper
It's quite common (in the s390 guest access code) to test if a guest
physical address points to a valid guest memory area or not.
So add a simple helper function in common code, since this might be
of interest for other architectures as well.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2014-04-22 13:24:35 +02:00
Michael S. Tsirkin 68c3b4d167 KVM: VMX: speed up wildcard MMIO EVENTFD
With KVM, MMIO is much slower than PIO, due to the need to
do page walk and emulation. But with EPT, it does not have to be: we
know the address from the VMCS so if the address is unique, we can look
up the eventfd directly, bypassing emulation.

Unfortunately, this only works if userspace does not need to match on
access length and data.  The implementation adds a separate FAST_MMIO
bus internally. This serves two purposes:
    - minimize overhead for old userspace that does not use eventfd with lengtth = 0
    - minimize disruption in other code (since we don't know the length,
      devices on the MMIO bus only get a valid address in write, this
      way we don't need to touch all devices to teach them to handle
      an invalid length)

At the moment, this optimization only has effect for EPT on x86.

It will be possible to speed up MMIO for NPT and MMU using the same
idea in the future.

With this patch applied, on VMX MMIO EVENTFD is essentially as fast as PIO.
I was unable to detect any measureable slowdown to non-eventfd MMIO.

Making MMIO faster is important for the upcoming virtio 1.0 which
includes an MMIO signalling capability.

The idea was suggested by Peter Anvin.  Lots of thanks to Gleb for
pre-review and suggestions.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2014-04-17 14:01:43 -03:00
Cornelia Huck f3f710bc64 KVM: Bump KVM_MAX_IRQ_ROUTES for s390
The maximum number for irq routes is currently 1024, which is a bit on
the small size for s390: We support up to 4 x 64k virtual devices with
up to 64 queues, and we need one route for each of the queues if we want
to operate it via irqfd.

Let's bump this to 4k on s390 for now, as this at least covers the saner
setups.

We need to find a more general solution, though, as we can't just grow
the routing table indefinitly.

Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-03-21 13:43:13 +01:00
Cornelia Huck 8422359877 KVM: s390: irq routing for adapter interrupts.
Introduce a new interrupt class for s390 adapter interrupts and enable
irqfds for s390.

This is depending on a new s390 specific vm capability, KVM_CAP_S390_IRQCHIP,
that needs to be enabled by userspace.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-03-21 13:43:00 +01:00
Takuya Yoshikawa 5befdc385d KVM: Simplify kvm->tlbs_dirty handling
When this was introduced, kvm_flush_remote_tlbs() could be called
without holding mmu_lock.  It is now acknowledged that the function
must be called before releasing mmu_lock, and all callers have already
been changed to do so.

There is no need to use smp_mb() and cmpxchg() any more.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-02-18 10:07:26 +01:00
Dominik Dingel e0ead41a6d KVM: async_pf: Provide additional direct page notification
By setting a Kconfig option, the architecture can control when
guest notifications will be presented by the apf backend.
There is the default batch mechanism, working as before, where the vcpu
thread should pull in this information.
Opposite to this, there is now the direct mechanism, that will push the
information to the guest.
This way s390 can use an already existing architecture interface.

Still the vcpu thread should call check_completion to cleanup leftovers.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2014-01-30 12:51:38 +01:00
Jens Freimann c05c4186bb KVM: s390: add floating irq controller
This patch adds a floating irq controller as a kvm_device.
It will be necessary for migration of floating interrupts as well
as for hardening the reset code by allowing user space to explicitly
remove all pending floating interrupts.

Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2014-01-30 10:25:20 +01:00
Stephen Hemminger ea0269bc34 kvm: remove dead code
The function kvm_io_bus_read_cookie is defined but never used
in current in-tree code.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2014-01-08 19:03:00 -02:00
Stephen Hemminger 7940876e13 kvm: make local functions static
Running 'make namespacecheck' found lots of functions that
should be declared static, since only used in one file.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2014-01-08 19:02:58 -02:00
Christoffer Dall 7330672bef KVM: arm-vgic: Support KVM_CREATE_DEVICE for VGIC
Support creating the ARM VGIC device through the KVM_CREATE_DEVICE
ioctl, which can then later be leveraged to use the
KVM_{GET/SET}_DEVICE_ATTR, which is useful both for setting addresses in
a more generic API than the ARM-specific one and is useful for
save/restore of VGIC state.

Adds KVM_CAP_DEVICE_CTRL to ARM capabilities.

Note that we change the check for creating a VGIC from bailing out if
any VCPUs were created, to bailing out if any VCPUs were ever run.  This
is an important distinction that shouldn't break anything, but allows
creating the VGIC after the VCPUs have been created.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2013-12-21 10:01:16 -08:00
Takuya Yoshikawa c08ac06ab3 KVM: Use cond_resched() directly and remove useless kvm_resched()
Since the commit 15ad7146 ("KVM: Use the scheduler preemption notifiers
to make kvm preemptible"), the remaining stuff in this function is a
simple cond_resched() call with an extra need_resched() check which was
there to avoid dropping VCPUs unnecessarily.  Now it is meaningless.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-12-13 14:23:45 +01:00
Gleb Natapov 95f328d3ad Merge branch 'kvm-ppc-queue' of git://github.com/agraf/linux-2.6 into queue
Conflicts:
	arch/powerpc/include/asm/processor.h
2013-11-04 10:20:57 +02:00
Michael S. Tsirkin 81e87e2679 kvm_host: typo fix
fix up typo in comment.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-31 22:14:23 +01:00
Alex Williamson e0f0bbc527 kvm: Create non-coherent DMA registeration
We currently use some ad-hoc arch variables tied to legacy KVM device
assignment to manage emulation of instructions that depend on whether
non-coherent DMA is present.  Create an interface for this, adapting
legacy KVM device assignment and adding VFIO via the KVM-VFIO device.
For now we assume that non-coherent DMA is possible any time we have a
VFIO group.  Eventually an interface can be developed as part of the
VFIO external user interface to query the coherency of a group.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30 19:02:23 +01:00
Alex Williamson d96eb2c6f4 kvm/x86: Convert iommu_flags to iommu_noncoherent
Default to operating in coherent mode.  This simplifies the logic when
we switch to a model of registering and unregistering noncoherent I/O
with KVM.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30 19:02:13 +01:00
Alex Williamson ec53500fae kvm: Add VFIO device
So far we've succeeded at making KVM and VFIO mostly unaware of each
other, but areas are cropping up where a connection beyond eventfds
and irqfds needs to be made.  This patch introduces a KVM-VFIO device
that is meant to be a gateway for such interaction.  The user creates
the device and can add and remove VFIO groups to it via file
descriptors.  When a group is added, KVM verifies the group is valid
and gets a reference to it via the VFIO external user interface.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30 19:02:03 +01:00
Aneesh Kumar K.V 5587027ce9 kvm: Add struct kvm arg to memslot APIs
We will use that in the later patch to find the kvm ops handler

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17 15:49:23 +02:00
chai wen f2e106692d KVM: Drop FOLL_GET in GUP when doing async page fault
Page pinning is not mandatory in kvm async page fault processing since
after async page fault event is delivered to a guest it accesses page once
again and does its own GUP.  Drop the FOLL_GET flag in GUP in async_pf
code, and do some simplifying in check/clear processing.

Suggested-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Gu zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: chai wen <chaiw.fnst@cn.fujitsu.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-10-15 13:43:37 +03:00
Christoffer Dall 6d9d41e574 KVM: Move gfn_to_index to x86 specific code
The gfn_to_index function relies on huge page defines which either may
not make sense on systems that don't support huge pages or are defined
in an unconvenient way for other architectures.  Since this is
x86-specific, move the function to arch/x86/include/asm/kvm_host.h.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-10-14 10:11:44 +03:00
Paolo Bonzini 2f303b74a6 KVM: Convert kvm_lock back to non-raw spinlock
In commit e935b8372c ("KVM: Convert kvm_lock to raw_spinlock"),
the kvm_lock was made a raw lock.  However, the kvm mmu_shrink()
function tries to grab the (non-raw) mmu_lock within the scope of
the raw locked kvm_lock being held.  This leads to the following:

BUG: sleeping function called from invalid context at kernel/rtmutex.c:659
in_atomic(): 1, irqs_disabled(): 0, pid: 55, name: kswapd0
Preemption disabled at:[<ffffffffa0376eac>] mmu_shrink+0x5c/0x1b0 [kvm]

Pid: 55, comm: kswapd0 Not tainted 3.4.34_preempt-rt
Call Trace:
 [<ffffffff8106f2ad>] __might_sleep+0xfd/0x160
 [<ffffffff817d8d64>] rt_spin_lock+0x24/0x50
 [<ffffffffa0376f3c>] mmu_shrink+0xec/0x1b0 [kvm]
 [<ffffffff8111455d>] shrink_slab+0x17d/0x3a0
 [<ffffffff81151f00>] ? mem_cgroup_iter+0x130/0x260
 [<ffffffff8111824a>] balance_pgdat+0x54a/0x730
 [<ffffffff8111fe47>] ? set_pgdat_percpu_threshold+0xa7/0xd0
 [<ffffffff811185bf>] kswapd+0x18f/0x490
 [<ffffffff81070961>] ? get_parent_ip+0x11/0x50
 [<ffffffff81061970>] ? __init_waitqueue_head+0x50/0x50
 [<ffffffff81118430>] ? balance_pgdat+0x730/0x730
 [<ffffffff81060d2b>] kthread+0xdb/0xe0
 [<ffffffff8106e122>] ? finish_task_switch+0x52/0x100
 [<ffffffff817e1e94>] kernel_thread_helper+0x4/0x10
 [<ffffffff81060c50>] ? __init_kthread_worker+0x

After the previous patch, kvm_lock need not be a raw spinlock anymore,
so change it back.

Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: kvm@vger.kernel.org
Cc: gleb@redhat.com
Cc: jan.kiszka@siemens.com
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-30 09:21:51 +02:00
Radim Krčmář 98fda16929 kvm: remove .done from struct kvm_async_pf
'.done' is used to mark the completion of 'async_pf_execute()', but
'cancel_work_sync()' returns true when the work was canceled, so we
use it instead.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-24 19:12:12 +02:00
Paolo Bonzini ba6a354154 KVM: mmu: allow page tables to be in read-only slots
Page tables in a read-only memory slot will currently cause a triple
fault because the page walker uses gfn_to_hva and it fails on such a slot.

OVMF uses such a page table; however, real hardware seems to be fine with
that as long as the accessed/dirty bits are set.  Save whether the slot
is readonly, and later check it when updating the accessed and dirty bits.

Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-17 12:52:31 +03:00
Dominik Dingel bf640876e2 KVM: s390: Make KVM_HVA_ERR_BAD usable on s390
Current common code uses PAGE_OFFSET to indicate a bad host virtual address.
As this check won't work on architectures that don't map kernel and user memory
into the same address space (e.g. s390), such architectures can now provide
their own KVM_HVA_ERR_BAD defines.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-29 09:03:53 +02:00
Takuya Yoshikawa e59dbe09f8 KVM: Introduce kvm_arch_memslots_updated()
This is called right after the memslots is updated, i.e. when the result
of update_memslots() gets installed in install_new_memslots().  Since
the memslots needs to be updated twice when we delete or move a memslot,
kvm_arch_commit_memory_region() does not correspond to this exactly.

In the following patch, x86 will use this new API to check if the mmio
generation has reached its maximum value, in which case mmio sptes need
to be flushed out.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Acked-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-18 12:29:25 +02:00
Cornelia Huck 126a5af520 KVM: kvm-io: support cookies
Add new functions kvm_io_bus_{read,write}_cookie() that allows users of
the kvm io infrastructure to use a cookie value to speed up lookup of a
device on an io bus.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-07-18 12:29:23 +02:00
Linus Torvalds fe489bf450 KVM fixes for 3.11
On the x86 side, there are some optimizations and documentation updates.
 The big ARM/KVM change for 3.11, support for AArch64, will come through
 Catalin Marinas's tree.  s390 and PPC have misc cleanups and bugfixes.
 
 There is a conflict due to "s390/pgtable: fix ipte notify bit" having
 entered 3.10 through Martin Schwidefsky's s390 tree.  This pull request
 has additional changes on top, so this tree's version is the correct one.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.13 (GNU/Linux)
 
 iQIcBAABAgAGBQJR0oU6AAoJEBvWZb6bTYbynnsP/RSUrrHrA8Wu1tqVfAKu+1y5
 6OIihqZ9x11/YMaNofAfv86jqxFu0/j7CzMGphNdjzujqKI+Q1tGe7oiVCmKzoG+
 UvSctWsz0lpllgBtnnrm5tcfmG6rrddhLtpA7m320+xCVx8KV5P4VfyHZEU+Ho8h
 ziPmb2mAQ65gBNX6nLHEJ3ITTgad6gt4NNbrKIYpyXuWZQJypzaRqT/vpc4md+Ed
 dCebMXsL1xgyb98EcnOdrWH1wV30MfucR7IpObOhXnnMKeeltqAQPvaOlKzZh4dK
 +QfxJfdRZVS0cepcxzx1Q2X3dgjoKQsHq1nlIyz3qu1vhtfaqBlixLZk0SguZ/R9
 1S1YqucZiLRO57RD4q0Ak5oxwobu18ZoqJZ6nledNdWwDe8bz/W2wGAeVty19ky0
 qstBdM9jnwXrc0qrVgZp3+s5dsx3NAm/KKZBoq4sXiDLd/yBzdEdWIVkIrU3X9wU
 3X26wOmBxtsB7so/JR7ciTsQHelmLicnVeXohAEP9CjIJffB81xVXnXs0P0SYuiQ
 RzbSCwjPzET4JBOaHWT0Dhv0DTS/EaI97KzlN32US3Bn3WiLlS1oDCoPFoaLqd2K
 LxQMsXS8anAWxFvexfSuUpbJGPnKSidSQoQmJeMGBa9QhmZCht3IL16/Fb641ToN
 xBohzi49L9FDbpOnTYfz
 =1zpG
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 "On the x86 side, there are some optimizations and documentation
  updates.  The big ARM/KVM change for 3.11, support for AArch64, will
  come through Catalin Marinas's tree.  s390 and PPC have misc cleanups
  and bugfixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (87 commits)
  KVM: PPC: Ignore PIR writes
  KVM: PPC: Book3S PR: Invalidate SLB entries properly
  KVM: PPC: Book3S PR: Allow guest to use 1TB segments
  KVM: PPC: Book3S PR: Don't keep scanning HPTEG after we find a match
  KVM: PPC: Book3S PR: Fix invalidation of SLB entry 0 on guest entry
  KVM: PPC: Book3S PR: Fix proto-VSID calculations
  KVM: PPC: Guard doorbell exception with CONFIG_PPC_DOORBELL
  KVM: Fix RTC interrupt coalescing tracking
  kvm: Add a tracepoint write_tsc_offset
  KVM: MMU: Inform users of mmio generation wraparound
  KVM: MMU: document fast invalidate all mmio sptes
  KVM: MMU: document fast invalidate all pages
  KVM: MMU: document fast page fault
  KVM: MMU: document mmio page fault
  KVM: MMU: document write_flooding_count
  KVM: MMU: document clear_spte_count
  KVM: MMU: drop kvm_mmu_zap_mmio_sptes
  KVM: MMU: init kvm generation close to mmio wrap-around value
  KVM: MMU: add tracepoint for check_mmio_spte
  KVM: MMU: fast invalidate all mmio sptes
  ...
2013-07-03 13:21:40 -07:00
Amos Kong 6ea34c9b78 kvm: exclude ioeventfd from counting kvm_io_range limit
We can easily reach the 1000 limit by start VM with a couple
hundred I/O devices (multifunction=on). The hardcode limit
already been adjusted 3 times (6 ~ 200 ~ 300 ~ 1000).

In userspace, we already have maximum file descriptor to
limit ioeventfd count. But kvm_io_bus devices also are used
for pit, pic, ioapic, coalesced_mmio. They couldn't be limited
by maximum file descriptor.

Currently only ioeventfds take too much kvm_io_bus devices,
so just exclude it from counting kvm_io_range limit.

Also fixed one indent issue in kvm_host.h

Signed-off-by: Amos Kong <akong@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-06-04 11:49:38 +03:00
Frederic Weisbecker 521921bad1 kvm: Move guest entry/exit APIs to context_tracking
The kvm_host.h header file doesn't handle well
inclusion when archs don't support KVM.

This results in build crashes for such archs when they
want to implement context tracking because this subsystem
includes kvm_host.h in order to implement the
guest_enter/exit APIs but it doesn't handle KVM off case.

To fix this, move the guest_enter()/guest_exit()
declarations and generic implementation to the context
tracking headers. These generic APIs actually belong to
this subsystem, besides other domains boundary tracking
like user_enter() et al.

KVM now properly becomes a user of this library, not the
other buggy way around.

Reported-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-05-31 11:32:30 +02:00
Marcelo Tosatti 0061d53daf KVM: x86: limit difference between kvmclock updates
kvmclock updates which are isolated to a given vcpu, such as vcpu->cpu
migration, should not allow system_timestamp from the rest of the vcpus
to remain static. Otherwise ntp frequency correction applies to one
vcpu's system_timestamp but not the others.

So in those cases, request a kvmclock update for all vcpus. The worst
case for a remote vcpu to update its kvmclock is then bounded by maximum
nohz sleep latency.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-15 20:36:09 +03:00
Linus Torvalds 01227a889e Merge tag 'kvm-3.10-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Gleb Natapov:
 "Highlights of the updates are:

  general:
   - new emulated device API
   - legacy device assignment is now optional
   - irqfd interface is more generic and can be shared between arches

  x86:
   - VMCS shadow support and other nested VMX improvements
   - APIC virtualization and Posted Interrupt hardware support
   - Optimize mmio spte zapping

  ppc:
    - BookE: in-kernel MPIC emulation with irqfd support
    - Book3S: in-kernel XICS emulation (incomplete)
    - Book3S: HV: migration fixes
    - BookE: more debug support preparation
    - BookE: e6500 support

  ARM:
   - reworking of Hyp idmaps

  s390:
   - ioeventfd for virtio-ccw

  And many other bug fixes, cleanups and improvements"

* tag 'kvm-3.10-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits)
  kvm: Add compat_ioctl for device control API
  KVM: x86: Account for failing enable_irq_window for NMI window request
  KVM: PPC: Book3S: Add API for in-kernel XICS emulation
  kvm/ppc/mpic: fix missing unlock in set_base_addr()
  kvm/ppc: Hold srcu lock when calling kvm_io_bus_read/write
  kvm/ppc/mpic: remove users
  kvm/ppc/mpic: fix mmio region lists when multiple guests used
  kvm/ppc/mpic: remove default routes from documentation
  kvm: KVM_CAP_IOMMU only available with device assignment
  ARM: KVM: iterate over all CPUs for CPU compatibility check
  KVM: ARM: Fix spelling in error message
  ARM: KVM: define KVM_ARM_MAX_VCPUS unconditionally
  KVM: ARM: Fix API documentation for ONE_REG encoding
  ARM: KVM: promote vfp_host pointer to generic host cpu context
  ARM: KVM: add architecture specific hook for capabilities
  ARM: KVM: perform HYP initilization for hotplugged CPUs
  ARM: KVM: switch to a dual-step HYP init code
  ARM: KVM: rework HYP page table freeing
  ARM: KVM: enforce maximum size for identity mapped code
  ARM: KVM: move to a KVM provided HYP idmap
  ...
2013-05-05 14:47:31 -07:00
Paul Mackerras 5975a2e095 KVM: PPC: Book3S: Add API for in-kernel XICS emulation
This adds the API for userspace to instantiate an XICS device in a VM
and connect VCPUs to it.  The API consists of a new device type for
the KVM_CREATE_DEVICE ioctl, a new capability KVM_CAP_IRQ_XICS, which
functions similarly to KVM_CAP_IRQ_MPIC, and the KVM_IRQ_LINE ioctl,
which is used to assert and deassert interrupt inputs of the XICS.

The XICS device has one attribute group, KVM_DEV_XICS_GRP_SOURCES.
Each attribute within this group corresponds to the state of one
interrupt source.  The attribute number is the same as the interrupt
source number.

This does not support irq routing or irqfd yet.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-05-02 15:28:36 +02:00
Alex Williamson 2a5bab1004 kvm: Allow build-time configuration of KVM device assignment
We hope to at some point deprecate KVM legacy device assignment in
favor of VFIO-based assignment.  Towards that end, allow legacy
device assignment to be deconfigured.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-28 12:58:56 +03:00
Gleb Natapov 064d1afaa5 Merge git://github.com/agraf/linux-2.6.git kvm-ppc-next into queue 2013-04-28 12:50:07 +03:00
Jan Kiszka 730dca42c1 KVM: x86: Rework request for immediate exit
The VMX implementation of enable_irq_window raised
KVM_REQ_IMMEDIATE_EXIT after we checked it in vcpu_enter_guest. This
caused infinite loops on vmentry. Fix it by letting enable_irq_window
signal the need for an immediate exit via its return value and drop
KVM_REQ_IMMEDIATE_EXIT.

This issue only affects nested VMX scenarios.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-28 12:44:18 +03:00
Scott Wood 07f0a7bdec kvm: destroy emulated devices on VM exit
The hassle of getting refcounting right was greater than the hassle
of keeping a list of devices to destroy on VM exit.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 20:27:28 +02:00
Scott Wood 5df554ad5b kvm/ppc/mpic: in-kernel MPIC emulation
Hook the MPIC code up to the KVM interfaces, add locking, etc.

Signed-off-by: Scott Wood <scottwood@freescale.com>
[agraf: add stub function for kvmppc_mpic_set_epr, non-booke, 64bit]
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 20:27:23 +02:00
Scott Wood 852b6d57dc kvm: add device control API
Currently, devices that are emulated inside KVM are configured in a
hardcoded manner based on an assumption that any given architecture
only has one way to do it.  If there's any need to access device state,
it is done through inflexible one-purpose-only IOCTLs (e.g.
KVM_GET/SET_LAPIC).  Defining new IOCTLs for every little thing is
cumbersome and depletes a limited numberspace.

This API provides a mechanism to instantiate a device of a certain
type, returning an ID that can be used to set/get attributes of the
device.  Attributes may include configuration parameters (e.g.
register base address), device state, operational commands, etc.  It
is similar to the ONE_REG API, except that it acts on devices rather
than vcpus.

Both device types and individual attributes can be tested without having
to create the device or get/set the attribute, without the need for
separately managing enumerated capabilities.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 20:27:20 +02:00
Alexander Graf e8cde0939d KVM: Move irq routing setup to irqchip.c
Setting up IRQ routes is nothing IOAPIC specific. Extract everything
that really is generic code into irqchip.c and only leave the ioapic
specific bits to irq_comm.c.

Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
2013-04-26 20:27:18 +02:00
Alexander Graf 7eee2efdc6 KVM: Remove kvm_get_intr_delivery_bitmask
The prototype has been stale for a while, I can't spot any real function
define behind it. Let's just remove it.

Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
2013-04-26 20:27:16 +02:00
Alexander Graf a725d56a02 KVM: Introduce CONFIG_HAVE_KVM_IRQ_ROUTING
Quite a bit of code in KVM has been conditionalized on availability of
IOAPIC emulation. However, most of it is generically applicable to
platforms that don't have an IOPIC, but a different type of irq chip.

Make code that only relies on IRQ routing, not an APIC itself, on
CONFIG_HAVE_KVM_IRQ_ROUTING, so that we can reuse it later.

Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
2013-04-26 20:27:14 +02:00
Alexander Graf 8175e5b79c KVM: Add KVM_IRQCHIP_NUM_PINS in addition to KVM_IOAPIC_NUM_PINS
The concept of routing interrupt lines to an irqchip is nothing
that is IOAPIC specific. Every irqchip has a maximum number of pins
that can be linked to irq lines.

So let's add a new define that allows us to reuse generic code for
non-IOAPIC platforms.

Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
2013-04-26 20:27:13 +02:00
Yang Zhang 3d81bc7e96 KVM: Call common update function when ioapic entry changed.
Both TMR and EOI exit bitmap need to be updated when ioapic changed
or vcpu's id/ldr/dfr changed. So use common function instead eoi exit
bitmap specific function.

Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-04-16 16:32:40 -03:00
Yang Zhang aa2fbe6d44 KVM: Let ioapic know the irq line status
Userspace may deliver RTC interrupt without query the status. So we
want to track RTC EOI for this case.

Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-04-15 23:20:34 -03:00
Geoff Levand 8b415dcd76 KVM: Move kvm_rebooting declaration out of x86
The variable kvm_rebooting is a common kvm variable, so move its
declaration from arch/x86/include/asm/kvm_host.h to
include/asm/kvm_host.h.

Fixes this sparse warning when building on arm64:

  virt/kvm/kvm_main.c⚠️ symbol 'kvm_rebooting' was not declared. Should it be static?

Signed-off-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-08 13:02:09 +03:00