Commit Graph

207 Commits

Author SHA1 Message Date
Christian Borntraeger
ccc40c53c0 KVM: s390: provide counters for all interrupt injects/delivery
For testing the exitless interrupt support it turned out useful to
have separate counters for inject and delivery of I/O interrupt.
While at it do the same for all interrupt types. For timer
related interrupts (clock comparator and cpu timer) we even had
no delivery counters. Fix this as well. On this way some counters
are being renamed to have a similar name.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2018-03-14 19:21:18 +00:00
QingFeng Hao
32de074909 KVM: add machine check counter to kvm_stat
This counter can be used for administration, debug or test purposes.

Suggested-by: Vladislav Mironov <mironov@de.ibm.com>
Signed-off-by: QingFeng Hao <haoqf@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-03-14 19:21:17 +00:00
David Hildenbrand
5fe01793dd KVM: s390: take care of clock-comparator sign control
Missed when enabling the Multiple-epoch facility. If the facility is
installed and the control is set, a sign based comaprison has to be
performed.

Right now we would inject wrong interrupts and ignore interrupt
conditions. Also the sleep time is calculated in a wrong way.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180207114647.6220-2-david@redhat.com>
Fixes: 8fa1696ea7 ("KVM: s390: Multiple Epoch Facility support")
Cc: stable@vger.kernel.org
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-02-20 20:50:29 +00:00
David Hildenbrand
baabee67f4 KVM: s390: use switch vs jump table in interrupt.c
Just like for the interception handlers, let's also use a switch-case
in our interrupt delivery code.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180206141743.24497-1-david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-02-14 13:53:43 +00:00
Christian Borntraeger
8846f3175c KVM: s390: do not set intervention requests for GISA interrupts
If GISA is available, we do not have to kick CPUs out of SIE to deliver
interrupts. The hardware can deliver such interrupts while running.

Cc: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-02-14 08:16:42 +00:00
Christian Borntraeger
a981032772 KVM: s390: optimize wakeup for exitless interrupts
For interrupt injection of floating interrupts we queue the interrupt
either in the GISA or in the floating  interrupt list. The first CPU
that looks at these data structures - either in KVM code or hardware
will then deliver that interrupt. To minimize latency we also:
-a: choose a VCPU to deliver that interrupt. We prefer idle CPUs
-b: we wake up the host thread that runs the VCPU
-c: set an I/O intervention bit for that CPU so that it exits guest
    context as soon as the PSW I/O mask is enabled
This will make sure that this CPU will execute the interrupt delivery
code of KVM very soon.

We can now optimize the injection case if we have exitless interrupts.
The wakeup is still necessary in case the target CPU sleeps. We can
avoid the I/O intervention request bit though. Whenever this
intervention request would be handled, the hardware could also directly
inject the interrupt on that CPU, no need to go through the interrupt
injection loop of KVM.

Cc: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-02-14 08:16:42 +00:00
Michael Mueller
4b9f952577 KVM: s390: introduce the format-1 GISA
The patch modifies the previously defined GISA data structure to be
able to store two GISA formats, format-0 and format-1. Additionally,
it verifies the availability of the GISA format facility and enables
the use of a format-1 GISA in the SIE control block accordingly.

A format-1 can do everything that format-0 can and we will need it
for real HW passthrough. As there are systems with only format-0
we keep both variants.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-26 14:13:58 +01:00
Michael Mueller
f180bfdae0 KVM: s390: activate GISA for emulated interrupts
If the AIV facility is available, a GISA will be used to manage emulated
adapter interrupts.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-26 14:13:57 +01:00
Michael Mueller
4b35f65e67 KVM: s390: make kvm_s390_get_io_int() aware of GISA
The function returns a pending I/O interrupt with the highest
priority defined by its ISC.

Together with AIV activation, pending adapter interrupts are
managed by the GISA IPM. Thus kvm_s390_get_io_int() needs to
inspect the IPM as well when the interrupt with the highest
priority has to be identified.

In case classic and adapter interrupts with the same ISC are
pending, the classic interrupt will be returned first.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-26 14:13:55 +01:00
Michael Mueller
24160af6cb KVM: s390: add GISA interrupts to FLIC ioctl interface
Pending interrupts marked in the GISA IPM are required to
become part of the answer of ioctl KVM_DEV_FLIC_GET_ALL_IRQS.

The ioctl KVM_DEV_FLIC_ENQUEUE is already capable to enqueue
adapter interrupts when a GISA is present.

With ioctl KVM_DEV_FLIC_CLEAR_IRQS the GISA IPM wil be cleared
now as well.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-26 11:12:10 +01:00
Michael Mueller
2496c8e7fe KVM: s390: abstract adapter interruption word generation from ISC
The function isc_to_int_word() allows the generation of interruption
words for adapter interrupts.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-26 11:12:09 +01:00
Michael Mueller
d7c5cb0105 KVM: s390: exploit GISA and AIV for emulated interrupts
The adapter interruption virtualization (AIV) facility is an
optional facility that comes with functionality expected to increase
the performance of adapter interrupt handling for both emulated and
passed-through adapter interrupts. With AIV, adapter interrupts can be
delivered to the guest without exiting SIE.

This patch provides some preparations for using AIV for emulated adapter
interrupts (including virtio) if it's available. When using AIV, the
interrupts are delivered at the so called GISA by setting the bit
corresponding to its Interruption Subclass (ISC) in the Interruption
Pending Mask (IPM) instead of inserting a node into the floating interrupt
list.

To keep the change reasonably small, the handling of this new state is
deferred in get_all_floating_irqs and handle_tpi. This patch concentrates
on the code handling enqueuement of emulated adapter interrupts, and their
delivery to the guest.

Note that care is still required for adapter interrupts using AIV,
because there is no guarantee that AIV is going to deliver the adapter
interrupts pending at the GISA (consider all vcpus idle). When delivering
GISA adapter interrupts by the host (usual mechanism) special attention
is required to honor interrupt priorities.

Empirical results show that the time window between making an interrupt
pending at the GISA and doing kvm_s390_deliver_pending_interrupts is
sufficient for a guest with at least moderate cpu activity to get adapter
interrupts delivered within the SIE, and potentially save some SIE exits
(if not other deliverable interrupts).

The code will be activated with a follow-up patch.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-26 11:11:39 +01:00
Michael Mueller
d77e64141e KVM: s390: implement GISA IPM related primitives
The patch implements routines to access the GISA to test and modify
its Interruption Pending Mask (IPM) from the host side.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-26 11:11:24 +01:00
Michael Mueller
c7901a6ebe KVM: s390: reverse bit ordering of irqs in pending mask
This patch prepares a simplification of bit operations between the irq
pending mask for emulated interrupts and the Interruption Pending Mask
(IPM) which is part of the Guest Interruption State Area (GISA), a feature
that allows interrupt delivery to guests by means of the SIE instruction.

Without that change, a bit-wise *or* operation on parts of these two masks
would either require a look-up table of size 256 bytes to map the IPM
to the emulated irq pending mask bit orientation (all bits mirrored at half
byte) or a sequence of up to 8 condidional branches to perform tests of
single bit positions. Both options are to be rejected either by performance
or space utilization reasons.

Beyond that this change will be transparent.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-26 09:49:09 +01:00
David Hildenbrand
8d5fb0dc4e KVM: s390: introduce and use kvm_s390_test_cpuflags()
Use it just like kvm_s390_set_cpuflags() and kvm_s390_clear_cpuflags().

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180123170531.13687-5-david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-24 17:46:42 +01:00
David Hildenbrand
9daecfc660 KVM: s390: introduce and use kvm_s390_clear_cpuflags()
Use it just like kvm_s390_set_cpuflags().

Suggested-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180123170531.13687-4-david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-24 17:46:42 +01:00
David Hildenbrand
ef8f4f49fc KVM: s390: reuse kvm_s390_set_cpuflags()
Use it in all places where we set cpuflags.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180123170531.13687-3-david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-24 17:46:41 +01:00
David Hildenbrand
2018224df3 KVM: s390: rename __set_cpuflag() to kvm_s390_set_cpuflags()
No need to make this function special. Move it to a header right away.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180123170531.13687-2-david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-24 17:46:41 +01:00
David Hildenbrand
a9f6c9a92f KVM: s390: cleanup struct kvm_s390_float_interrupt
"wq" is not used at all. "cpuflags" can be access directly via the vcpu,
just as "float_int" via vcpu->kvm.
While at it, reuse _set_cpuflag() to make the code look nicer.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180108193747.10818-1-david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-16 16:15:18 +01:00
Michael Mueller
588629385c KVM: s390: drop use of spin lock in __floating_irq_kick
It is not required to take to a lock to protect access to the cpuflags
of the local interrupt structure of a vcpu as the performed operation
is an atomic_or.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-16 16:15:18 +01:00
Greg Kroah-Hartman
940f89a5a3 KVM: s390: Remove redundant license text
Now that the SPDX tag is in all arch/s390/kvm/ files, that identifies
the license in a specific and legally-defined manner.  So the extra GPL
text wording can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text.  And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Message-Id: <20171124140043.10062-9-gregkh@linuxfoundation.org>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-12-06 09:18:42 +01:00
Greg Kroah-Hartman
d809aa2387 KVM: s390: add SPDX identifiers to the remaining files
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the arch/s390/kvm/ files with the correct SPDX license
identifier based on the license text in the file itself.  The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Message-Id: <20171124140043.10062-3-gregkh@linuxfoundation.org>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-12-06 09:18:39 +01:00
Linus Torvalds
974aa5630b First batch of KVM changes for 4.15
Common:
  - Python 3 support in kvm_stat
 
  - Accounting of slabs to kmemcg
 
 ARM:
  - Optimized arch timer handling for KVM/ARM
 
  - Improvements to the VGIC ITS code and introduction of an ITS reset
    ioctl
 
  - Unification of the 32-bit fault injection logic
 
  - More exact external abort matching logic
 
 PPC:
  - Support for running hashed page table (HPT) MMU mode on a host that
    is using the radix MMU mode;  single threaded mode on POWER 9 is
    added as a pre-requisite
 
  - Resolution of merge conflicts with the last second 4.14 HPT fixes
 
  - Fixes and cleanups
 
 s390:
  - Some initial preparation patches for exitless interrupts and crypto
 
  - New capability for AIS migration
 
  - Fixes
 
 x86:
  - Improved emulation of LAPIC timer mode changes, MCi_STATUS MSRs, and
    after-reset state
 
  - Refined dependencies for VMX features
 
  - Fixes for nested SMI injection
 
  - A lot of cleanups
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Merge tag 'kvm-4.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Radim Krčmář:
 "First batch of KVM changes for 4.15

  Common:
   - Python 3 support in kvm_stat
   - Accounting of slabs to kmemcg

  ARM:
   - Optimized arch timer handling for KVM/ARM
   - Improvements to the VGIC ITS code and introduction of an ITS reset
     ioctl
   - Unification of the 32-bit fault injection logic
   - More exact external abort matching logic

  PPC:
   - Support for running hashed page table (HPT) MMU mode on a host that
     is using the radix MMU mode; single threaded mode on POWER 9 is
     added as a pre-requisite
   - Resolution of merge conflicts with the last second 4.14 HPT fixes
   - Fixes and cleanups

  s390:
   - Some initial preparation patches for exitless interrupts and crypto
   - New capability for AIS migration
   - Fixes

  x86:
   - Improved emulation of LAPIC timer mode changes, MCi_STATUS MSRs,
     and after-reset state
   - Refined dependencies for VMX features
   - Fixes for nested SMI injection
   - A lot of cleanups"

* tag 'kvm-4.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (89 commits)
  KVM: s390: provide a capability for AIS state migration
  KVM: s390: clear_io_irq() requests are not expected for adapter interrupts
  KVM: s390: abstract conversion between isc and enum irq_types
  KVM: s390: vsie: use common code functions for pinning
  KVM: s390: SIE considerations for AP Queue virtualization
  KVM: s390: document memory ordering for kvm_s390_vcpu_wakeup
  KVM: PPC: Book3S HV: Cosmetic post-merge cleanups
  KVM: arm/arm64: fix the incompatible matching for external abort
  KVM: arm/arm64: Unify 32bit fault injection
  KVM: arm/arm64: vgic-its: Implement KVM_DEV_ARM_ITS_CTRL_RESET
  KVM: arm/arm64: Document KVM_DEV_ARM_ITS_CTRL_RESET
  KVM: arm/arm64: vgic-its: Free caches when GITS_BASER Valid bit is cleared
  KVM: arm/arm64: vgic-its: New helper functions to free the caches
  KVM: arm/arm64: vgic-its: Remove kvm_its_unmap_device
  arm/arm64: KVM: Load the timer state when enabling the timer
  KVM: arm/arm64: Rework kvm_timer_should_fire
  KVM: arm/arm64: Get rid of kvm_timer_flush_hwstate
  KVM: arm/arm64: Avoid phys timer emulation in vcpu entry/exit
  KVM: arm/arm64: Move phys_timer_emulate function
  KVM: arm/arm64: Use kvm_arm_timer_set/get_reg for guest register traps
  ...
2017-11-16 13:00:24 -08:00
Michael Mueller
4dd6f17eb9 KVM: s390: clear_io_irq() requests are not expected for adapter interrupts
There is a chance to delete not yet delivered I/O interrupts if an
exploiter uses the subsystem identification word 0x0000 while
processing a KVM_DEV_FLIC_CLEAR_IO_IRQ ioctl. -EINVAL will be returned
now instead in that case.

Classic interrupts will always have bit 0x10000 set in the schid while
adapter interrupts have a zero schid. The clear_io_irq interface is
only useful for classic interrupts (as adapter interrupts belong to
many devices). Let's make this interface more strict and forbid a schid
of 0.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-11-09 09:49:48 +01:00
Michael Mueller
ee739f4b21 KVM: s390: abstract conversion between isc and enum irq_types
The abstraction of the conversion between an isc value and an irq_type
by means of functions isc_to_irq_type() and irq_type_to_isc() allows
to clarify the respective operations where used.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-11-09 09:49:48 +01:00
Christian Borntraeger
72e1ad4200 KVM: s390: document memory ordering for kvm_s390_vcpu_wakeup
swait_active does not enforce any ordering and it can therefore trigger
some subtle races when the CPU moves the read for the check before a
previous store and that store is then used on another CPU that is
preparing the swait.

On s390 there is a call to swait_active in kvm_s390_vcpu_wakeup. The
good thing is, on s390 all potential races cannot happen because all
callers of kvm_s390_vcpu_wakeup do not store (no race) or use an atomic
operation, which handles memory ordering. Since this is not guaranteed
by the Linux semantics (but by the implementation on s390) let's add
smp_mb_after_atomic to make this obvious and document the ordering.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-11-09 09:35:06 +01:00
Martin Schwidefsky
cc65450c83 s390/ctl_reg: move control register definitions to ctl_reg.h
The nmi.h header has some constant defines for control register bits.
These definitions should really be located in ctl_reg.h. Move and
rename the defines.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-10-19 17:07:37 +02:00
David Hildenbrand
3dbf0205b1 KVM: s390: use WARN_ON_ONCE only for checking
Move the real logic that always has to be executed out of the
WARN_ON_ONCE.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170830160603.5452-3-david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-08-31 13:49:39 +02:00
Linus Torvalds
c136b84393 PPC:
- Better machine check handling for HV KVM
 - Ability to support guests with threads=2, 4 or 8 on POWER9
 - Fix for a race that could cause delayed recognition of signals
 - Fix for a bug where POWER9 guests could sleep with interrupts pending.
 
 ARM:
 - VCPU request overhaul
 - allow timer and PMU to have their interrupt number selected from userspace
 - workaround for Cavium erratum 30115
 - handling of memory poisonning
 - the usual crop of fixes and cleanups
 
 s390:
 - initial machine check forwarding
 - migration support for the CMMA page hinting information
 - cleanups and fixes
 
 x86:
 - nested VMX bugfixes and improvements
 - more reliable NMI window detection on AMD
 - APIC timer optimizations
 
 Generic:
 - VCPU request overhaul + documentation of common code patterns
 - kvm_stat improvements
 
 There is a small conflict in arch/s390 due to an arch-wide field rename.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "PPC:
   - Better machine check handling for HV KVM
   - Ability to support guests with threads=2, 4 or 8 on POWER9
   - Fix for a race that could cause delayed recognition of signals
   - Fix for a bug where POWER9 guests could sleep with interrupts pending.

  ARM:
   - VCPU request overhaul
   - allow timer and PMU to have their interrupt number selected from userspace
   - workaround for Cavium erratum 30115
   - handling of memory poisonning
   - the usual crop of fixes and cleanups

  s390:
   - initial machine check forwarding
   - migration support for the CMMA page hinting information
   - cleanups and fixes

  x86:
   - nested VMX bugfixes and improvements
   - more reliable NMI window detection on AMD
   - APIC timer optimizations

  Generic:
   - VCPU request overhaul + documentation of common code patterns
   - kvm_stat improvements"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (124 commits)
  Update my email address
  kvm: vmx: allow host to access guest MSR_IA32_BNDCFGS
  x86: kvm: mmu: use ept a/d in vmcs02 iff used in vmcs12
  kvm: x86: mmu: allow A/D bits to be disabled in an mmu
  x86: kvm: mmu: make spte mmio mask more explicit
  x86: kvm: mmu: dead code thanks to access tracking
  KVM: PPC: Book3S: Fix typo in XICS-on-XIVE state saving code
  KVM: PPC: Book3S HV: Close race with testing for signals on guest entry
  KVM: PPC: Book3S HV: Simplify dynamic micro-threading code
  KVM: x86: remove ignored type attribute
  KVM: LAPIC: Fix lapic timer injection delay
  KVM: lapic: reorganize restart_apic_timer
  KVM: lapic: reorganize start_hv_timer
  kvm: nVMX: Check memory operand to INVVPID
  KVM: s390: Inject machine check into the nested guest
  KVM: s390: Inject machine check into the guest
  tools/kvm_stat: add new interactive command 'b'
  tools/kvm_stat: add new command line switch '-i'
  tools/kvm_stat: fix error on interactive command 'g'
  KVM: SVM: suppress unnecessary NMI singlestep on GIF=0 and nested exit
  ...
2017-07-06 18:38:31 -07:00
QingFeng Hao
4d62fcc0b6 KVM: s390: Inject machine check into the guest
If the exit flag of SIE indicates that a machine check has happened
during guest's running and needs to be injected, inject it to the guest
accordingly.
But some machine checks, e.g. Channel Report Pending (CRW), refer to
host conditions only (the guest's channel devices are not managed by
the kernel directly) and are therefore not injected into the guest.
External Damage (ED) is also not reinjected into the guest because ETR
conditions are gone in Linux and STP conditions are not enabled in the
guest, and ED contains only these 8 ETR and STP conditions.
In general, instruction-processing damage, system recovery,
storage error, service-processor damage and channel subsystem damage
will be reinjected into the guest, and the remain (System damage,
timing-facility damage, warning, ED and CRW) will be handled on the host.

Signed-off-by: QingFeng Hao <haoqf@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-06-28 12:42:32 +02:00
Yi Min Zhao
2c1a48f2e5 KVM: S390: add new group for flic
In some cases, userspace needs to get or set all ais states for example
migration. So we introduce a new group KVM_DEV_FLIC_AISM_ALL to provide
interfaces to get or set the adapter-interruption-suppression mode for
all ISCs. The corresponding documentation is updated.

Signed-off-by: Yi Min Zhao <zyimin@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-06-22 12:41:07 +02:00
Christian Borntraeger
1ba15b24f0 KVM: s390: fix ais handling vs cpu model
If ais is disabled via cpumodel, we must act accordingly, even if
KVM_CAP_S390_AIS was enabled.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Reviewed-by: Yi Min Zhao <zyimin@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
2017-05-31 19:54:49 +02:00
Christian Borntraeger
8024855999 KVM: s390: fix stale machine check data for guarded storage
When delivering a machine check the CPU state is "loaded", which
means that some registers are already in the host registers.
Before writing the register content into the machine check
save area, we must make sure that we save the content of the
registers into the data structures that are used for delivering
the machine check.
We already do the right thing for access, vector/floating point
registers, let's do the same for guarded storage.

Fixes: 4e0b1ab72b ("KVM: s390: gs support for kvm guests")
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-04-12 13:48:35 +02:00
Yi Min Zhao
a892095013 KVM: s390: introduce adapter interrupt inject function
Inject adapter interrupts on a specified adapter which allows to
retrieve the adapter flags, e.g. if the adapter is subject to AIS
facility or not. And add documentation for this interface.

For adapters subject to AIS, handle the airq injection suppression
for a given ISC according to the interruption mode:
- before injection, if NO-Interruptions Mode, just return 0 and
  suppress, otherwise, allow the injection.
- after injection, if SINGLE-Interruption Mode, change it to
  NO-Interruptions Mode to suppress the following interrupts.

Besides, add tracepoint for suppressed airq and AIS mode transitions.

Signed-off-by: Yi Min Zhao <zyimin@linux.vnet.ibm.com>
Signed-off-by: Fei Li <sherrylf@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-04-06 13:15:37 +02:00
Fei Li
5197839354 KVM: s390: introduce ais mode modify function
Provide an interface for userspace to modify AIS
(adapter-interruption-suppression) mode state, and add documentation
for the interface. Allowed target modes are ALL-Interruptions mode
and SINGLE-Interruption mode.

We introduce the 'simm' and 'nimm' fields in kvm_s390_float_interrupt
to store interruption modes for each ISC. Each bit in 'simm' and
'nimm' targets to one ISC, and collaboratively indicate three modes:
ALL-Interruptions, SINGLE-Interruption and NO-Interruptions. This
interface can initiate most transitions between the states; transition
from SINGLE-Interruption to NO-Interruptions via adapter interrupt
injection will be introduced in a following patch. The meaningful
combinations are as follows:

    interruption mode | simm bit | nimm bit
    ------------------|----------|----------
             ALL      |    0     |     0
           SINGLE     |    1     |     0
             NO       |    1     |     1

Besides, add tracepoint to track AIS mode transitions.

Co-Authored-By: Yi Min Zhao <zyimin@linux.vnet.ibm.com>
Signed-off-by: Yi Min Zhao <zyimin@linux.vnet.ibm.com>
Signed-off-by: Fei Li <sherrylf@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-04-06 13:15:36 +02:00
Fei Li
08fab50da6 KVM: s390: interface for suppressible I/O adapters
In order to properly implement adapter-interruption suppression, we
need a way for userspace to specify which adapters are subject to
suppression. Let's convert the existing (and unused) 'pad' field into
a 'flags' field and define a flag value for suppressible adapters.

Besides, add documentation for the interface.

Signed-off-by: Fei Li <sherrylf@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-04-06 13:15:36 +02:00
Fan Zhang
4e0b1ab72b KVM: s390: gs support for kvm guests
This patch adds guarded storage support for KVM guest. We need to
setup the necessary control blocks, the kvm_run structure for the
new registers, the necessary wrappers for VSIE, as well as the
machine check save areas.
GS is enabled lazily and the register saving and reloading is done in
KVM code.  As this feature adds new content for migration, we provide
a new capability for enablement (KVM_CAP_S390_GS).

Signed-off-by: Fan Zhang <zhangfan@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-03-22 18:59:33 +01:00
Martin Schwidefsky
916cda1aa1 s390: add a system call for guarded storage
This adds a new system call to enable the use of guarded storage for
user space processes. The system call takes two arguments, a command
and pointer to a guarded storage control block:

    s390_guarded_storage(int command, struct gs_cb *gs_cb);

The second argument is relevant only for the GS_SET_BC_CB command.

The commands in detail:

0 - GS_ENABLE
    Enable the guarded storage facility for the current task. The
    initial content of the guarded storage control block will be
    all zeros. After the enablement the user space code can use
    load-guarded-storage-controls instruction (LGSC) to load an
    arbitrary control block. While a task is enabled the kernel
    will save and restore the current content of the guarded
    storage registers on context switch.
1 - GS_DISABLE
    Disables the use of the guarded storage facility for the current
    task. The kernel will cease to save and restore the content of
    the guarded storage registers, the task specific content of
    these registers is lost.
2 - GS_SET_BC_CB
    Set a broadcast guarded storage control block. This is called
    per thread and stores a specific guarded storage control block
    in the task struct of the current task. This control block will
    be used for the broadcast event GS_BROADCAST.
3 - GS_CLEAR_BC_CB
    Clears the broadcast guarded storage control block. The guarded-
    storage control block is removed from the task struct that was
    established by GS_SET_BC_CB.
4 - GS_BROADCAST
    Sends a broadcast to all thread siblings of the current task.
    Every sibling that has established a broadcast guarded storage
    control block will load this control block and will be enabled
    for guarded storage. The broadcast guarded storage control block
    is used up, a second broadcast without a refresh of the stored
    control block with GS_SET_BC_CB will not have any effect.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-03-22 08:14:25 +01:00
Thomas Gleixner
8b0e195314 ktime: Cleanup ktime_set() usage
ktime_set(S,N) was required for the timespec storage type and is still
useful for situations where a Seconds and Nanoseconds part of a time value
needs to be converted. For anything where the Seconds argument is 0, this
is pointless and can be replaced with a simple assignment.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
2016-12-25 17:21:22 +01:00
Linus Torvalds
7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Christian Borntraeger
31d8b8d41a KVM: s390: handle access registers in the run ioctl not in vcpu_put/load
Right now we save the host access registers in kvm_arch_vcpu_load
and load them in kvm_arch_vcpu_put. Vice versa for the guest access
registers. On schedule this means, that we load/save access registers
multiple times.

e.g. VCPU_RUN with just one reschedule and then return does

[from user space via VCPU_RUN]
- save the host registers in kvm_arch_vcpu_load (via ioctl)
- load the guest registers in kvm_arch_vcpu_load (via ioctl)
- do guest stuff
- decide to schedule/sleep
- save the guest registers in kvm_arch_vcpu_put (via sched)
- load the host registers in kvm_arch_vcpu_put (via sched)
- save the host registers in switch_to (via sched)
- schedule
- return
- load the host registers in switch_to (via sched)
- save the host registers in kvm_arch_vcpu_load (via sched)
- load the guest registers in kvm_arch_vcpu_load (via sched)
- do guest stuff
- decide to go to userspace
- save the guest registers in kvm_arch_vcpu_put (via ioctl)
- load the host registers in kvm_arch_vcpu_put (via ioctl)
[back to user space]

As the kernel does not use access registers, we can avoid
this reloading and simply piggy back on switch_to (let it save
the guest values instead of host values in thread.acrs) by
moving the host/guest switch into the VCPU_RUN ioctl function.
We now do

[from user space via VCPU_RUN]
- save the host registers in kvm_arch_vcpu_ioctl_run
- load the guest registers in kvm_arch_vcpu_ioctl_run
- do guest stuff
- decide to schedule/sleep
- save the guest registers in switch_to
- schedule
- return
- load the guest registers in switch_to (via sched)
- do guest stuff
- decide to go to userspace
- save the guest registers in kvm_arch_vcpu_ioctl_run
- load the host registers in kvm_arch_vcpu_ioctl_run

This seems to save about 10% of the vcpu_put/load functions
according to perf.

As vcpu_load no longer switches the acrs, We can also loading
the acrs in kvm_arch_vcpu_ioctl_set_sregs.

Suggested-by: Fan Zhang <zhangfan@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-11-22 19:32:35 +01:00
David Hildenbrand
a6940674c3 KVM: s390: allow 255 VCPUs when sca entries aren't used
If the SCA entries aren't used by the hardware (no SIGPIF), we
can simply not set the entries, stick to the basic sca and allow more
than 64 VCPUs.

To hinder any other facility from using these entries, let's properly
provoke intercepts by not setting the MCN and keeping the entries
unset.

This effectively allows when running KVM under KVM (vSIE) or under z/VM to
provide more than 64 VCPUs to a guest. Let's limit it to 255 for now, to
not run into problems if the CPU numbers are limited somewhere else.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 13:40:53 +02:00
David Hildenbrand
8953fb08ab KVM: s390: write external damage code on machine checks
Let's also write the external damage code already provided by
struct kvm_s390_mchk_info.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 09:07:52 +02:00
David Hildenbrand
ff5dc1492a KVM: s390: fix delivery of vector regs during machine checks
Vector registers are only to be stored if the facility is available
and if the guest has set up the machine check extended save area.

If anything goes wrong while writing the vector registers, the vector
registers are to be marked as invalid. Please note that we are allowed
to write the registers although they are marked as invalid.

Machine checks and "store status" SIGP orders are two different concepts,
let's correctly separate these. As the SIGP part is completely handled in
user space, we can drop it.

This patch is based on a patch from Cornelia Huck.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 09:07:52 +02:00
David Hildenbrand
0319dae677 KVM: s390: split store status and machine check handling
Store status writes the prefix which is not to be done by a machine check.
Also, the psw is stored and later on overwritten by the failing-storage
address, which looks strange at first sight.

Store status and machine check handling look similar, but they are actually
two different things.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 09:07:51 +02:00
David Hildenbrand
d6404ded30 KVM: s390: factor out actual delivery of machine checks
Let's factor this out to prepare for bigger changes. Reorder to calls to
match the logical order given in the PoP.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 09:07:51 +02:00
Radim Krčmář
c63cf538eb KVM: pass struct kvm to kvm_set_routing_entry
Arch-specific code will use it.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 09:03:56 +02:00
David Hildenbrand
adbf16985c KVM: s390: vsie: speed up VCPU irq delivery when handling vsie
Whenever we want to wake up a VCPU (e.g. when injecting an IRQ), we
have to kick it out of vsie, so the request will be handled faster.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:44 +02:00
Christian Borntraeger
dcc98ea614 KVM: s390: fixup I/O interrupt traces
We currently have two issues with the I/O  interrupt injection logging:
1. All QEMU versions up to 2.6 have a wrong encoding of device numbers
etc for the I/O interrupt type, so the inject VM_EVENT will have wrong
data. Let's fix this by using the interrupt parameters and not the
interrupt type number.
2. We only log in kvm_s390_inject_vm, but not when coming from
kvm_s390_reinject_io_int or from flic. Let's move the logging to the
common __inject_io function.

We also enhance the logging for delivery to match the data.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-06-10 12:07:26 +02:00
Christian Borntraeger
3491caf275 KVM: halt_polling: provide a way to qualify wakeups during poll
Some wakeups should not be considered a sucessful poll. For example on
s390 I/O interrupts are usually floating, which means that _ALL_ CPUs
would be considered runnable - letting all vCPUs poll all the time for
transactional like workload, even if one vCPU would be enough.
This can result in huge CPU usage for large guests.
This patch lets architectures provide a way to qualify wakeups if they
should be considered a good/bad wakeups in regard to polls.

For s390 the implementation will fence of halt polling for anything but
known good, single vCPU events. The s390 implementation for floating
interrupts does a wakeup for one vCPU, but the interrupt will be delivered
by whatever CPU checks first for a pending interrupt. We prefer the
woken up CPU by marking the poll of this CPU as "good" poll.
This code will also mark several other wakeup reasons like IPI or
expired timers as "good". This will of course also mark some events as
not sucessful. As  KVM on z runs always as a 2nd level hypervisor,
we prefer to not poll, unless we are really sure, though.

This patch successfully limits the CPU usage for cases like uperf 1byte
transactional ping pong workload or wakeup heavy workload like OLTP
while still providing a proper speedup.

This also introduced a new vcpu stat "halt_poll_no_tuning" that marks
wakeups that are considered not good for polling.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Radim Krčmář <rkrcmar@redhat.com> (for an earlier version)
Cc: David Matlack <dmatlack@google.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
[Rename config symbol. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-13 17:29:23 +02:00