Commit Graph

285 Commits

Author SHA1 Message Date
Bharata B Rao 22945688ac KVM: PPC: Book3S HV: Support reset of secure guest
Add support for reset of secure guest via a new ioctl KVM_PPC_SVM_OFF.
This ioctl will be issued by QEMU during reset and includes the
the following steps:

- Release all device pages of the secure guest.
- Ask UV to terminate the guest via UV_SVM_TERMINATE ucall
- Unpin the VPA pages so that they can be migrated back to secure
  side when guest becomes secure again. This is required because
  pinned pages can't be migrated.
- Reinit the partition scoped page tables

After these steps, guest is ready to issue UV_ESM call once again
to switch to secure mode.

Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
	[Implementation of uv_svm_terminate() and its call from
	guest shutdown path]
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
	[Unpinning of VPA pages]
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-11-28 17:02:31 +11:00
Fabiano Rosas 1a9167a214 KVM: PPC: Report single stepping capability
When calling the KVM_SET_GUEST_DEBUG ioctl, userspace might request
the next instruction to be single stepped via the
KVM_GUESTDBG_SINGLESTEP control bit of the kvm_guest_debug structure.

This patch adds the KVM_CAP_PPC_GUEST_DEBUG_SSTEP capability in order
to inform userspace about the state of single stepping support.

We currently don't have support for guest single stepping implemented
in Book3S HV so the capability is only present for Book3S PR and
BookE.

Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-10-21 15:55:22 +11:00
Paolo Bonzini 8146856b0a PPC KVM update for 5.4
- Some prep for extending the uses of the rmap array
 - Various minor fixes
 - Commits from the powerpc topic/ppc-kvm branch, which fix a problem
   with interrupts arriving after free_irq, causing host hangs and crashes.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQEcBAABCAAGBQJdZwd7AAoJEJ2a6ncsY3GffDQH/2q+c2z56ZO2lzfk4Hy9piWn
 Z9PR9n72Z6TiMyVCl7CtLCyI+lRy3QVZnol14ugQNX4aFJiiwDGRHJF0wNxjeok4
 4DAIqBc60qD2dkp1LwtUM1YsLsr/n3tdrGU1b0VrHGoGTVhJDpbjhJsblXZ1ujGr
 KxQ1Uf4XsW5T7kovHuzj+FFlbB5nbEX5cBIU68maBGZSCl355wCOW35rKVITTIIv
 +VKkO2aNbk6bRmZmOi2v1D65eQa2+TKe/o48TneJv1WhL4h4hDyHdmVeWRNoAI6C
 ve8mwCAVs7IITjCJ1qcGnI8NzVxMlXgwVir7sQ1aslRLZfeRAm5FOIPNEz1ADXs=
 =3oLd
 -----END PGP SIGNATURE-----

Merge tag 'kvm-ppc-next-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD

PPC KVM update for 5.4

- Some prep for extending the uses of the rmap array
- Various minor fixes
- Commits from the powerpc topic/ppc-kvm branch, which fix a problem
  with interrupts arriving after free_irq, causing host hangs and crashes.
2019-09-10 16:51:17 +02:00
Paul Mackerras 2ad7a27dea KVM: PPC: Book3S: Enable XIVE native capability only if OPAL has required functions
There are some POWER9 machines where the OPAL firmware does not support
the OPAL_XIVE_GET_QUEUE_STATE and OPAL_XIVE_SET_QUEUE_STATE calls.
The impact of this is that a guest using XIVE natively will not be able
to be migrated successfully.  On the source side, the get_attr operation
on the KVM native device for the KVM_DEV_XIVE_GRP_EQ_CONFIG attribute
will fail; on the destination side, the set_attr operation for the same
attribute will fail.

This adds tests for the existence of the OPAL get/set queue state
functions, and if they are not supported, the XIVE-native KVM device
is not created and the KVM_CAP_PPC_IRQ_XIVE capability returns false.
Userspace can then either provide a software emulation of XIVE, or
else tell the guest that it does not have a XIVE controller available
to it.

Cc: stable@vger.kernel.org # v5.2+
Fixes: 3fab2d1058 ("KVM: PPC: Book3S HV: XIVE: Activate XIVE exploitation mode")
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-08-27 11:45:49 +10:00
Paolo Bonzini 741cbbae07 KVM: remove kvm_arch_has_vcpu_debugfs()
There is no need for this function as all arches have to implement
kvm_arch_create_vcpu_debugfs() no matter what.  A #define symbol
let us actually simplify the code.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-08-05 12:55:48 +02:00
Wanpeng Li 17e433b543 KVM: Fix leak vCPU's VMCS value into other pCPU
After commit d73eb57b80 (KVM: Boost vCPUs that are delivering interrupts), a
five years old bug is exposed. Running ebizzy benchmark in three 80 vCPUs VMs
on one 80 pCPUs Skylake server, a lot of rcu_sched stall warning splatting
in the VMs after stress testing:

 INFO: rcu_sched detected stalls on CPUs/tasks: { 4 41 57 62 77} (detected by 15, t=60004 jiffies, g=899, c=898, q=15073)
 Call Trace:
   flush_tlb_mm_range+0x68/0x140
   tlb_flush_mmu.part.75+0x37/0xe0
   tlb_finish_mmu+0x55/0x60
   zap_page_range+0x142/0x190
   SyS_madvise+0x3cd/0x9c0
   system_call_fastpath+0x1c/0x21

swait_active() sustains to be true before finish_swait() is called in
kvm_vcpu_block(), voluntarily preempted vCPUs are taken into account
by kvm_vcpu_on_spin() loop greatly increases the probability condition
kvm_arch_vcpu_runnable(vcpu) is checked and can be true, when APICv
is enabled the yield-candidate vCPU's VMCS RVI field leaks(by
vmx_sync_pir_to_irr()) into spinning-on-a-taken-lock vCPU's current
VMCS.

This patch fixes it by checking conservatively a subset of events.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Marc Zyngier <Marc.Zyngier@arm.com>
Cc: stable@vger.kernel.org
Fixes: 98f4a1467 (KVM: add kvm_arch_vcpu_runnable() test to kvm_vcpu_on_spin() loop)
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-08-05 12:55:47 +02:00
Paolo Bonzini a45ff5994c KVM/arm updates for 5.3
- Add support for chained PMU counters in guests
 - Improve SError handling
 - Handle Neoverse N1 erratum #1349291
 - Allow side-channel mitigation status to be migrated
 - Standardise most AArch64 system register accesses to msr_s/mrs_s
 - Fix host MPIDR corruption on 32bit
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAl0kge4VHG1hcmMuenlu
 Z2llckBhcm0uY29tAAoJECPQ0LrRPXpDYyQP/3XY5tFcLKkp/h9rnGaCXwAxhNzn
 TyF/IZEFBKFTSoDMXKLLc8KllvoPQ7aUl03heYbuayYpyKR1+LCx7lDwu1MYyEf+
 aSSuOKlbG//tLUEGp09pTRCgjs2mhhZYqOj5GF2mZ7xpovFVSNOPzTazbXDNQ7tw
 zUAs43YNg+bUMwj+SLWpBlizjrLr7T34utIr6daKJE/GSfmIrcYXhGbZqUh0zbO0
 z5LNasebws8/pHyeGI7+/yoMIKaQ8foMgywTpsRpBsx6YI+AbOLjEmCk2IBOPcEK
 pm9KkSIBZEO2CSxZKl3NQiEow/Qd/lnz2xLMCSfh4XrYoI2Th4gNcsbJpiBDWP5a
 0eZ5jSiexxKngIbM+to7jR3m0yc9RgcuzceJg3Uly7Ya0vb5RqKwOX4Ge4XP4VDT
 DzIVFdQjxDKdVIf3EvGp1cj4P7dRUU3xbZcbzyuRPEmT3vgjEnbxawmPLs3QMAl1
 31Wd2wIsPB86kSxzSMel27Vs5VgMhgyHE26zN91R745CvhDXaDKydIWjGjdVMHsB
 GuX/h2kL+ohx+N/OpZPgwsVUAGLSOQFP3pE/EcGtqc2kkfqa+bx12DKcZ3zdmJvy
 +cu5ixU8q5thPH/pZob/C3hKUY/eLy02emS34RK0Jh2sZHbQgAOtMsiqUxNHEjUm
 6TkpdWa5SRd7CtGV
 =yfCs
 -----END PGP SIGNATURE-----

Merge tag 'kvm-arm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm updates for 5.3

- Add support for chained PMU counters in guests
- Improve SError handling
- Handle Neoverse N1 erratum #1349291
- Allow side-channel mitigation status to be migrated
- Standardise most AArch64 system register accesses to msr_s/mrs_s
- Fix host MPIDR corruption on 32bit
2019-07-11 15:14:16 +02:00
Thomas Gleixner d94d71cb45 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 266
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not write to the free
  software foundation 51 franklin street fifth floor boston ma 02110
  1301 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 67 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141333.953658117@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:30:28 +02:00
Sean Christopherson f257d6dcda KVM: Directly return result from kvm_arch_check_processor_compat()
Add a wrapper to invoke kvm_arch_check_processor_compat() so that the
boilerplate ugliness of checking virtualization support on all CPUs is
hidden from the arch specific code.  x86's implementation in particular
is quite heinous, as it unnecessarily propagates the out-param pattern
into kvm_x86_ops.

While the x86 specific issue could be resolved solely by changing
kvm_x86_ops, make the change for all architectures as returning a value
directly is prettier and technically more robust, e.g. s390 doesn't set
the out param, which could lead to subtle breakage in the (highly
unlikely) scenario where the out-param was not pre-initialized by the
caller.

Opportunistically annotate svm_check_processor_compat() with __init.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-04 19:27:32 +02:00
Thomas Huth a86cb413f4 KVM: s390: Do not report unusabled IDs via KVM_CAP_MAX_VCPU_ID
KVM_CAP_MAX_VCPU_ID is currently always reporting KVM_MAX_VCPU_ID on all
architectures. However, on s390x, the amount of usable CPUs is determined
during runtime - it is depending on the features of the machine the code
is running on. Since we are using the vcpu_id as an index into the SCA
structures that are defined by the hardware (see e.g. the sca_add_vcpu()
function), it is not only the amount of CPUs that is limited by the hard-
ware, but also the range of IDs that we can use.
Thus KVM_CAP_MAX_VCPU_ID must be determined during runtime on s390x, too.
So the handling of KVM_CAP_MAX_VCPU_ID has to be moved from the common
code into the architecture specific code, and on s390x we have to return
the same value here as for KVM_CAP_MAX_VCPUS.
This problem has been discovered with the kvm_create_max_vcpus selftest.
With this change applied, the selftest now passes on s390x, too.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20190523164309.13345-9-thuth@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2019-05-28 15:52:19 +02:00
Paolo Bonzini 59c5c58c5b Second PPC KVM update for 5.2
- Fix a bug, fix a spelling mistake, remove some useless code.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQEcBAABCAAGBQJc2kTEAAoJEJ2a6ncsY3GfS88IAImcIlKXMvzSKtHFxGpRap17
 9LTZs5MQAUZHVMFJXmrJLBgogtGxUw53aX53woeyerytZsoGU4+YzwgLhk4XBEzA
 5Kt5ahlxu82sa2ThH1zyLlNWFXiTECgD5ErNTdavLbNlaKE8YG160+65/mSyixGz
 vs5wLSYGv/37no1ay6PIZ3DtwqdrYq5nJbuG+ZsaamUHPJOGprqHqg0gaTJ877NZ
 yQDUS7OVuEJ1pdUUK/elP+cnlqR9smaP5OUNsXYMHWJgPJMjc27/thBJy93iS1kk
 /zKQ8AFmxqoaePnR7ymTbqurfFFHBiSavUmyWopSQppNHCf4DDE8XjLs9MXKez8=
 =Lco4
 -----END PGP SIGNATURE-----

Merge tag 'kvm-ppc-next-5.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD

PPC KVM update for 5.2

* Support for guests to access the new POWER9 XIVE interrupt controller
  hardware directly, reducing interrupt latency and overhead for guests.

* In-kernel implementation of the H_PAGE_INIT hypercall.

* Reduce memory usage of sparsely-populated IOMMU tables.

* Several bug fixes.

Second PPC KVM update for 5.2

* Fix a bug, fix a spelling mistake, remove some useless code.
2019-05-15 23:39:38 +02:00
Cédric Le Goater 3fab2d1058 KVM: PPC: Book3S HV: XIVE: Activate XIVE exploitation mode
Full support for the XIVE native exploitation mode is now available,
advertise the capability KVM_CAP_PPC_IRQ_XIVE for guests running on
PowerNV KVM Hypervisors only. Support for nested guests (pseries KVM
Hypervisor) is not yet available. XIVE should also have been activated
which is default setting on POWER9 systems running a recent Linux
kernel.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-04-30 19:35:16 +10:00
Cédric Le Goater eacc56bb9d KVM: PPC: Book3S HV: XIVE: Introduce a new capability KVM_CAP_PPC_IRQ_XIVE
The user interface exposes a new capability KVM_CAP_PPC_IRQ_XIVE to
let QEMU connect the vCPU presenters to the XIVE KVM device if
required. The capability is not advertised for now as the full support
for the XIVE native exploitation mode is not yet available. When this
is case, the capability will be advertised on PowerNV Hypervisors
only. Nested guests (pseries KVM Hypervisor) are not supported.

Internally, the interface to the new KVM device is protected with a
new interrupt mode: KVMPPC_IRQ_XIVE.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-04-30 19:35:16 +10:00
Paolo Bonzini c110ae578c kvm: move KVM_CAP_NR_MEMSLOTS to common code
All architectures except MIPS were defining it in the same way,
and memory slots are handled entirely by common code so there
is no point in keeping the definition per-architecture.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-04-16 15:39:08 +02:00
Suraj Jitindar Singh 2b57ecd020 KVM: PPC: Book3S: Add count cache flush parameters to kvmppc_get_cpu_char()
Add KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST &
KVM_PPC_CPU_BEHAV_FLUSH_COUNT_CACHE to the characteristics returned
from the H_GET_CPU_CHARACTERISTICS H-CALL, as queried from either the
hypervisor or the device tree.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-03-01 15:11:14 +11:00
Paul Mackerras 03f953329b KVM: PPC: Book3S: Allow XICS emulation to work in nested hosts using XIVE
Currently, the KVM code assumes that if the host kernel is using the
XIVE interrupt controller (the new interrupt controller that first
appeared in POWER9 systems), then the in-kernel XICS emulation will
use the XIVE hardware to deliver interrupts to the guest.  However,
this only works when the host is running in hypervisor mode and has
full access to all of the XIVE functionality.  It doesn't work in any
nested virtualization scenario, either with PR KVM or nested-HV KVM,
because the XICS-on-XIVE code calls directly into the native-XIVE
routines, which are not initialized and cannot function correctly
because they use OPAL calls, and OPAL is not available in a guest.

This means that using the in-kernel XICS emulation in a nested
hypervisor that is using XIVE as its interrupt controller will cause a
(nested) host kernel crash.  To fix this, we change most of the places
where the current code calls xive_enabled() to select between the
XICS-on-XIVE emulation and the plain XICS emulation to call a new
function, xics_on_xive(), which returns false in a guest.

However, there is a further twist.  The plain XICS emulation has some
functions which are used in real mode and access the underlying XICS
controller (the interrupt controller of the host) directly.  In the
case of a nested hypervisor, this means doing XICS hypercalls
directly.  When the nested host is using XIVE as its interrupt
controller, these hypercalls will fail.  Therefore this also adds
checks in the places where the XICS emulation wants to access the
underlying interrupt controller directly, and if that is XIVE, makes
the code use the virtual mode fallback paths, which call generic
kernel infrastructure rather than doing direct XICS access.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-19 16:00:15 +11:00
Radim Krčmář cfdfaf4a86 PPC KVM update for 4.21
The main new feature this time is support in HV nested KVM for passing
 a device that is emulated by a level 0 hypervisor and presented to
 level 1 as a PCI device through to a level 2 guest using VFIO.
 
 Apart from that there are improvements for migration of radix guests
 under HV KVM and some other fixes and cleanups.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQEcBAABCAAGBQJcGFzEAAoJEJ2a6ncsY3GfKjoH/Azcf8QIO5ftyHrjazFZOSUh
 5Lr24HZTYHheowp6obzuZWRAIyckHmflRmOkv8RVGuA8+Sp+m5pBxN3WTVPOwDUh
 WanOWVGJsuhl6qATmkm7xIxmYhQEyLxVNbnWva7WXuZ92rgGCNfHtByHWAx/7vTe
 q5Shr4fLIQ8HRzor8Xqqph1I0hQNTE9VsaK1hW/PxI0gsO8qjDwOR8SDpT/aaJrS
 Sir+lM0TwCbJREuObDxYAXn1OWy8rMYjlb9fEBv5tmPCQKiB9vJz4tV+ahR9eJ14
 PEF57MoBOGwzQXo4geFLuo/Bu8fDygKsKQX1eYGcn6tRGA4pnTxzYl0+dHLBkOM=
 =3WkD
 -----END PGP SIGNATURE-----

Merge tag 'kvm-ppc-next-4.21-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc

PPC KVM update for 4.21 from Paul Mackerras

The main new feature this time is support in HV nested KVM for passing
a device that is emulated by a level 0 hypervisor and presented to
level 1 as a PCI device through to a level 2 guest using VFIO.

Apart from that there are improvements for migration of radix guests
under HV KVM and some other fixes and cleanups.
2018-12-20 14:54:09 +01:00
Suraj Jitindar Singh 873db2cd9a KVM: PPC: Book3S HV: Allow passthrough of an emulated device to an L2 guest
Allow for a device which is being emulated at L0 (the host) for an L1
guest to be passed through to a nested (L2) guest.

The existing kvmppc_hv_emulate_mmio function can be used here. The main
challenge is that for a load the result must be stored into the L2 gpr,
not an L1 gpr as would normally be the case after going out to qemu to
complete the operation. This presents a challenge as at this point the
L2 gpr state has been written back into L1 memory.

To work around this we store the address in L1 memory of the L2 gpr
where the result of the load is to be stored and use the new io_gpr
value KVM_MMIO_REG_NESTED_GPR to indicate that this is a nested load for
which completion must be done when returning back into the kernel. Then
in kvmppc_complete_mmio_load() the resultant value is written into L1
memory at the location of the indicated L2 gpr.

Note that we don't currently let an L1 guest emulate a device for an L2
guest which is then passed through to an L3 guest.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-12-17 11:33:50 +11:00
Suraj Jitindar Singh cc6929cc84 KVM: PPC: Update kvmppc_st and kvmppc_ld to use quadrants
The functions kvmppc_st and kvmppc_ld are used to access guest memory
from the host using a guest effective address. They do so by translating
through the process table to obtain a guest real address and then using
kvm_read_guest or kvm_write_guest to make the access with the guest real
address.

This method of access however only works for L1 guests and will give the
incorrect results for a nested guest.

We can however use the store_to_eaddr and load_from_eaddr kvmppc_ops to
perform the access for a nested guesti (and a L1 guest). So attempt this
method first and fall back to the old method if this fails and we aren't
running a nested guest.

At this stage there is no fall back method to perform the access for a
nested guest and this is left as a future improvement. For now we will
return to the nested guest and rely on the fact that a translation
should be faulted in before retrying the access.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-12-17 11:33:50 +11:00
Suraj Jitindar Singh 693ac10a88 KVM: PPC: Book3S: Only report KVM_CAP_SPAPR_TCE_VFIO on powernv machines
The kvm capability KVM_CAP_SPAPR_TCE_VFIO is used to indicate the
availability of in kernel tce acceleration for vfio. However it is
currently the case that this is only available on a powernv machine,
not for a pseries machine.

Thus make this capability dependent on having the cpu feature
CPU_FTR_HVMODE.

[paulus@ozlabs.org - fixed compilation for Book E.]

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-12-17 11:33:49 +11:00
Bharata B Rao f032b73459 KVM: PPC: Pass change type down to memslot commit function
Currently, kvm_arch_commit_memory_region() gets called with a
parameter indicating what type of change is being made to the memslot,
but it doesn't pass it down to the platform-specific memslot commit
functions.  This adds the `change' parameter to the lower-level
functions so that they can use it in future.

[paulus@ozlabs.org - fix book E also.]

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-12-17 10:57:27 +11:00
Paolo Bonzini e5d83c74a5 kvm: make KVM_CAP_ENABLE_CAP_VM architecture agnostic
The first such capability to be handled in virt/kvm/ will be manual
dirty page reprotection.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 12:34:18 +01:00
Paul Mackerras aa069a9969 KVM: PPC: Book3S HV: Add a VM capability to enable nested virtualization
With this, userspace can enable a KVM-HV guest to run nested guests
under it.

The administrator can control whether any nested guests can be run;
setting the "nested" module parameter to false prevents any guests
becoming nested hypervisors (that is, any attempt to enable the nested
capability on a guest will fail).  Guests which are already nested
hypervisors will continue to be so.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-10-09 16:14:47 +11:00
Paul Mackerras de760db4d9 KVM: PPC: Book3S HV: Allow HV module to load without hypervisor mode
With this, the KVM-HV module can be loaded in a guest running under
KVM-HV, and if the hypervisor supports nested virtualization, this
guest can now act as a nested hypervisor and run nested guests.

This also adds some checks to inform userspace that HPT guests are not
supported by nested hypervisors (by returning false for the
KVM_CAP_PPC_MMU_HASH_V3 capability), and to prevent userspace from
configuring a guest to use HPT mode.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09 16:04:27 +11:00
Linus Torvalds e61cf2e3a5 Minor code cleanups for PPC.
For x86 this brings in PCID emulation and CR3 caching for shadow page
 tables, nested VMX live migration, nested VMCS shadowing, an optimized
 IPI hypercall, and some optimizations.
 
 ARM will come next week.
 
 There is a semantic conflict because tip also added an .init_platform
 callback to kvm.c.  Please keep the initializer from this branch,
 and add a call to kvmclock_init (added by tip) inside kvm_init_platform
 (added here).
 
 Also, there is a backmerge from 4.18-rc6.  This is because of a
 refactoring that conflicted with a relatively late bugfix and
 resulted in a particularly hellish conflict.  Because the conflict
 was only due to unfortunate timing of the bugfix, I backmerged and
 rebased the refactoring rather than force the resolution on you.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQEcBAABAgAGBQJbdwNFAAoJEL/70l94x66DiPEH/1cAGZWGd85Y3yRu1dmTmqiz
 kZy0V+WTQ5kyJF4ZsZKKOp+xK7Qxh5e9kLdTo70uPZCHwLu9IaGKN9+dL9Jar3DR
 yLPX5bMsL8UUed9g9mlhdaNOquWi7d7BseCOnIyRTolb+cqnM5h3sle0gqXloVrS
 UQb4QogDz8+86czqR8tNfazjQRKW/D2HEGD5NDNVY1qtpY+leCDAn9/u6hUT5c6z
 EtufgyDh35UN+UQH0e2605gt3nN3nw3FiQJFwFF1bKeQ7k5ByWkuGQI68XtFVhs+
 2WfqL3ftERkKzUOy/WoSJX/C9owvhMcpAuHDGOIlFwguNGroZivOMVnACG1AI3I=
 =9Mgw
 -----END PGP SIGNATURE-----

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

Pull first set of KVM updates from Paolo Bonzini:
 "PPC:
   - minor code cleanups

  x86:
   - PCID emulation and CR3 caching for shadow page tables
   - nested VMX live migration
   - nested VMCS shadowing
   - optimized IPI hypercall
   - some optimizations

  ARM will come next week"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (85 commits)
  kvm: x86: Set highest physical address bits in non-present/reserved SPTEs
  KVM/x86: Use CC_SET()/CC_OUT in arch/x86/kvm/vmx.c
  KVM: X86: Implement PV IPIs in linux guest
  KVM: X86: Add kvm hypervisor init time platform setup callback
  KVM: X86: Implement "send IPI" hypercall
  KVM/x86: Move X86_CR4_OSXSAVE check into kvm_valid_sregs()
  KVM: x86: Skip pae_root shadow allocation if tdp enabled
  KVM/MMU: Combine flushing remote tlb in mmu_set_spte()
  KVM: vmx: skip VMWRITE of HOST_{FS,GS}_BASE when possible
  KVM: vmx: skip VMWRITE of HOST_{FS,GS}_SEL when possible
  KVM: vmx: always initialize HOST_{FS,GS}_BASE to zero during setup
  KVM: vmx: move struct host_state usage to struct loaded_vmcs
  KVM: vmx: compute need to reload FS/GS/LDT on demand
  KVM: nVMX: remove a misleading comment regarding vmcs02 fields
  KVM: vmx: rename __vmx_load_host_state() and vmx_save_host_state()
  KVM: vmx: add dedicated utility to access guest's kernel_gs_base
  KVM: vmx: track host_state.loaded using a loaded_vmcs pointer
  KVM: vmx: refactor segmentation code in vmx_save_host_state()
  kvm: nVMX: Fix fault priority for VMX operations
  kvm: nVMX: Fix fault vector for VMX operation at CPL > 0
  ...
2018-08-19 10:38:36 -07:00
Christophe Leroy 45ef5992e0 powerpc: remove unnecessary inclusion of asm/tlbflush.h
asm/tlbflush.h is only needed for:
- using functions xxx_flush_tlb_xxx()
- using MMU_NO_CONTEXT
- including asm-generic/pgtable.h

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-30 22:48:20 +10:00
Simon Guo 4eeb85568e KVM: PPC: Remove mmio_vsx_tx_sx_enabled in KVM MMIO emulation
Originally PPC KVM MMIO emulation uses only 0~31#(5 bits) for VSR
reg number, and use mmio_vsx_tx_sx_enabled field together for
0~63# VSR regs.

Currently PPC KVM MMIO emulation is reimplemented with analyse_instr()
assistance.  analyse_instr() returns 0~63 for VSR register number, so
it is not necessary to use additional mmio_vsx_tx_sx_enabled field
any more.

This patch extends related reg bits (expand io_gpr to u16 from u8
and use 6 bits for VSR reg#), so that mmio_vsx_tx_sx_enabled can
be removed.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-07-18 15:14:45 +10:00
Paolo Bonzini 09027ab73b Merge tag 'kvm-ppc-next-4.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD 2018-06-14 17:42:54 +02:00
Souptick Joarder 1499fa809e kvm: Change return type to vm_fault_t
Use new return type vm_fault_t for fault handler. For
now, this is just documenting that the function returns
a VM_FAULT value rather than an errno. Once all instances
are converted, vm_fault_t will become a distinct type.

commit 1c8f422059 ("mm: change return type to vm_fault_t")

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-01 19:18:25 +02:00
Simon Guo c8235c2891 KVM: PPC: Remove load/put vcpu for KVM_GET/SET_ONE_REG ioctl
Since the vcpu mutex locking/unlock has been moved out of vcpu_load()
/vcpu_put(), KVM_GET_ONE_REG and KVM_SET_ONE_REG doesn't need to do
ioctl with loading vcpu anymore. This patch removes vcpu_load()/vcpu_put()
from KVM_GET_ONE_REG and KVM_SET_ONE_REG ioctl.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:30:59 +10:00
Simon Guo b3cebfe8c1 KVM: PPC: Move vcpu_load/vcpu_put down to each ioctl case in kvm_arch_vcpu_ioctl
Although we already have kvm_arch_vcpu_async_ioctl() which doesn't require
ioctl to load vcpu, the sync ioctl code need to be cleaned up when
CONFIG_HAVE_KVM_VCPU_ASYNC_IOCTL is not configured.

This patch moves vcpu_load/vcpu_put down to each ioctl switch case so that
each ioctl can decide to do vcpu_load/vcpu_put or not independently.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:30:53 +10:00
Simon Guo d234d68eb7 KVM: PPC: Book3S PR: Enable HTM for PR KVM for KVM_CHECK_EXTENSION ioctl
With current patch set, PR KVM now supports HTM. So this patch turns it
on for PR KVM.

Tested with:
https://github.com/justdoitqd/publicFiles/blob/master/test_kvm_htm_cap.c

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-06-01 10:30:48 +10:00
Simon Guo acc9eb9305 KVM: PPC: Reimplement LOAD_VMX/STORE_VMX instruction mmio emulation with analyse_instr() input
This patch reimplements LOAD_VMX/STORE_VMX MMIO emulation with
analyse_instr() input. When emulating the store, the VMX reg will need to
be flushed so that the right reg val can be retrieved before writing to
IO MEM.

This patch also adds support for lvebx/lvehx/lvewx/stvebx/stvehx/stvewx
MMIO emulation. To meet the requirement of handling different element
sizes, kvmppc_handle_load128_by2x64()/kvmppc_handle_store128_by2x64()
were replaced with kvmppc_handle_vmx_load()/kvmppc_handle_vmx_store().

The framework used is similar to VSX instruction MMIO emulation.

Suggested-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-22 19:53:00 +10:00
Simon Guo da2a32b876 KVM: PPC: Expand mmio_vsx_copy_type to cover VMX load/store element types
VSX MMIO emulation uses mmio_vsx_copy_type to represent VSX emulated
element size/type, such as KVMPPC_VSX_COPY_DWORD_LOAD, etc. This
patch expands mmio_vsx_copy_type to cover VMX copy type, such as
KVMPPC_VMX_COPY_BYTE(stvebx/lvebx), etc. As a result,
mmio_vsx_copy_type is also renamed to mmio_copy_type.

It is a preparation for reimplementing VMX MMIO emulation.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-22 19:52:55 +10:00
Simon Guo 2e6baa46b4 KVM: PPC: Add giveup_ext() hook to PPC KVM ops
Currently HV will save math regs(FP/VEC/VSX) when trap into host. But
PR KVM will only save math regs when qemu task switch out of CPU, or
when returning from qemu code.

To emulate FP/VEC/VSX mmio load, PR KVM need to make sure that math
regs were flushed firstly and then be able to update saved VCPU
FPR/VEC/VSX area reasonably.

This patch adds giveup_ext() field to KVM ops. Only PR KVM has non-NULL
giveup_ext() ops. kvmppc_complete_mmio_load() can invoke that hook
(when not NULL) to flush math regs accordingly, before updating saved
register vals.

Math regs flush is also necessary for STORE, which will be covered
in later patch within this patch series.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-22 19:51:13 +10:00
Simon Guo 94dd7fa1c0 KVM: PPC: Add KVMPPC_VSX_COPY_WORD_LOAD_DUMP type support for mmio emulation
Some VSX instructions like lxvwsx will splat word into VSR. This patch
adds a new VSX copy type KVMPPC_VSX_COPY_WORD_LOAD_DUMP to support this.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-22 19:51:03 +10:00
Simon Guo f19d1f367a KVM: PPC: Fix a mmio_host_swabbed uninitialized usage issue
When KVM emulates VMX store, it will invoke kvmppc_get_vmx_data() to
retrieve VMX reg val. kvmppc_get_vmx_data() will check mmio_host_swabbed
to decide which double word of vr[] to be used. But the
mmio_host_swabbed can be uninitialized during VMX store procedure:

kvmppc_emulate_loadstore
	\- kvmppc_handle_store128_by2x64
		\- kvmppc_get_vmx_data

So vcpu->arch.mmio_host_swabbed is not meant to be used at all for
emulation of store instructions, and this patch makes that true for
VMX stores. This patch also initializes mmio_host_swabbed to avoid
possible future problems.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-18 15:38:23 +10:00
Michael Ellerman a26cf1c9fe Merge branch 'topic/ppc-kvm' into next
This brings in two series from Paul, one of which touches KVM code and
may need to be merged into the kvm-ppc tree to resolve conflicts.
2018-03-24 08:43:18 +11:00
Paul Mackerras 4bb3c7a020 KVM: PPC: Book3S HV: Work around transactional memory bugs in POWER9
POWER9 has hardware bugs relating to transactional memory and thread
reconfiguration (changes to hardware SMT mode).  Specifically, the core
does not have enough storage to store a complete checkpoint of all the
architected state for all four threads.  The DD2.2 version of POWER9
includes hardware modifications designed to allow hypervisor software
to implement workarounds for these problems.  This patch implements
those workarounds in KVM code so that KVM guests see a full, working
transactional memory implementation.

The problems center around the use of TM suspended state, where the
CPU has a checkpointed state but execution is not transactional.  The
workaround is to implement a "fake suspend" state, which looks to the
guest like suspended state but the CPU does not store a checkpoint.
In this state, any instruction that would cause a transition to
transactional state (rfid, rfebb, mtmsrd, tresume) or would use the
checkpointed state (treclaim) causes a "soft patch" interrupt (vector
0x1500) to the hypervisor so that it can be emulated.  The trechkpt
instruction also causes a soft patch interrupt.

On POWER9 DD2.2, we avoid returning to the guest in any state which
would require a checkpoint to be present.  The trechkpt in the guest
entry path which would normally create that checkpoint is replaced by
either a transition to fake suspend state, if the guest is in suspend
state, or a rollback to the pre-transactional state if the guest is in
transactional state.  Fake suspend state is indicated by a flag in the
PACA plus a new bit in the PSSCR.  The new PSSCR bit is write-only and
reads back as 0.

On exit from the guest, if the guest is in fake suspend state, we still
do the treclaim instruction as we would in real suspend state, in order
to get into non-transactional state, but we do not save the resulting
register state since there was no checkpoint.

Emulation of the instructions that cause a softpatch interrupt is
handled in two paths.  If the guest is in real suspend mode, we call
kvmhv_p9_tm_emulation_early() to handle the cases where the guest is
transitioning to transactional state.  This is called before we do the
treclaim in the guest exit path; because we haven't done treclaim, we
can get back to the guest with the transaction still active.  If the
instruction is a case that kvmhv_p9_tm_emulation_early() doesn't
handle, or if the guest is in fake suspend state, then we proceed to
do the complete guest exit path and subsequently call
kvmhv_p9_tm_emulation() in host context with the MMU on.  This handles
all the cases including the cases that generate program interrupts
(illegal instruction or TM Bad Thing) and facility unavailable
interrupts.

The emulation is reasonably straightforward and is mostly concerned
with checking for exception conditions and updating the state of
registers such as MSR and CR0.  The treclaim emulation takes care to
ensure that the TEXASR register gets updated as if it were the guest
treclaim instruction that had done failure recording, not the treclaim
done in hypervisor state in the guest exit path.

With this, the KVM_CAP_PPC_HTM capability returns true (1) even if
transactional memory is not available to host userspace.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-24 00:39:13 +11:00
Paul Mackerras 6df3877fc9 KVM: PPC: Book3S: Fix compile error that occurs with some gcc versions
Some versions of gcc generate a warning that the variable "emulated"
may be used uninitialized in function kvmppc_handle_load128_by2x64().
It would be used uninitialized if kvmppc_handle_load128_by2x64 was
ever called with vcpu->arch.mmio_vmx_copy_nums == 0, but neither of
the callers ever do that, so there is no actual bug.  When gcc
generates a warning, it causes the build to fail because arch/powerpc
is compiled with -Werror.

This silences the warning by initializing "emulated" to EMULATE_DONE.

Fixes: 09f984961c ("KVM: PPC: Book3S: Add MMIO emulation for VMX instructions")
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-02-13 15:45:21 +11:00
Paul Mackerras c662f77331 KVM: PPC: Fix compile error that occurs when CONFIG_ALTIVEC=n
Commit accb757d79 ("KVM: Move vcpu_load to arch-specific
kvm_arch_vcpu_ioctl_run", 2017-12-04) added a "goto out"
statement and an "out:" label to kvm_arch_vcpu_ioctl_run().
Since the only "goto out" is inside a CONFIG_VSX block,
compiling with CONFIG_VSX=n gives a warning that label "out"
is defined but not used, and because arch/powerpc is compiled
with -Werror, that becomes a compile error that makes the kernel
build fail.

Merge commit 1ab03c072f ("Merge tag 'kvm-ppc-next-4.16-2' of
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc",
2018-02-09) added a similar block of code inside a #ifdef
CONFIG_ALTIVEC, with a "goto out" statement.

In order to make the build succeed, this adds a #ifdef around the
"out:" label.  This is a minimal, ugly fix, to be replaced later
by a refactoring of the code.  Since CONFIG_VSX depends on
CONFIG_ALTIVEC, it is sufficient to use #ifdef CONFIG_ALTIVEC here.

Fixes: accb757d79 ("KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl_run")
Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-02-13 15:23:39 +11:00
Radim Krčmář 1ab03c072f Second PPC KVM update for 4.16
Seven fixes that are either trivial or that address bugs that people
 are actually hitting.  The main ones are:
 
 - Drop spinlocks before reading guest memory
 
 - Fix a bug causing corruption of VCPU state in PR KVM with preemption
   enabled
 
 - Make HPT resizing work on POWER9
 
 - Add MMIO emulation for vector loads and stores, because guests now
   use these instructions in memcpy and similar routines.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJafWn0AAoJEJ2a6ncsY3GfaMsIANF0hQD8SS78WNKnoy0vnZ/X
 PUXdjwHEsfkg5KdQ7o0oaa2BJHHqO3vozddmMiG14r2L1mNCHJpnVZCVV0GaEJcZ
 eU8++OPK6yrsPNNpAjnrtQ0Vk4LwzoT0bftEjS3TtLt1s2uSo+R1+HLmxbxGhQUX
 bZngo9wQ3cjUfAXLrPtAVhE5wTmgVOiufVRyfRsBRdFzRsAWqjY4hBtJAfwdff4r
 AA5H0RCrXO6e1feKr5ElU8KzX6b7IjH9Xu868oJ1r16zZfE05PBl1X5n4XG7XDm7
 xWvs8uLAB7iRv2o/ecFznYJ+Dz1NCBVzD0RmAUTqPCcVKDrxixaTkqMPFW97IAA=
 =HOJR
 -----END PGP SIGNATURE-----

Merge tag 'kvm-ppc-next-4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc

Second PPC KVM update for 4.16

Seven fixes that are either trivial or that address bugs that people
are actually hitting.  The main ones are:

- Drop spinlocks before reading guest memory

- Fix a bug causing corruption of VCPU state in PR KVM with preemption
  enabled

- Make HPT resizing work on POWER9

- Add MMIO emulation for vector loads and stores, because guests now
  use these instructions in memcpy and similar routines.
2018-02-09 22:03:06 +01:00
Jose Ricardo Ziviani 09f984961c KVM: PPC: Book3S: Add MMIO emulation for VMX instructions
This patch provides the MMIO load/store vector indexed
X-Form emulation.

Instructions implemented:
lvx: the quadword in storage addressed by the result of EA &
0xffff_ffff_ffff_fff0 is loaded into VRT.

stvx: the contents of VRS are stored into the quadword in storage
addressed by the result of EA & 0xffff_ffff_ffff_fff0.

Reported-by: Gopesh Kumar Chaudhary <gopchaud@in.ibm.com>
Reported-by: Balamuruhan S <bala24@linux.vnet.ibm.com>
Signed-off-by: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-02-09 16:51:51 +11:00
David Gibson 790a9df5fb KVM: PPC: Book3S HV: Make HPT resizing work on POWER9
This adds code to enable the HPT resizing code to work on POWER9,
which uses a slightly modified HPT entry format compared to POWER8.
On POWER9, we convert HPTEs read from the HPT from the new format to
the old format so that the rest of the HPT resizing code can work as
before.  HPTEs written to the new HPT are converted to the new format
as the last step before writing them into the new HPT.

This takes out the checks added by commit bcd3bb63db ("KVM: PPC:
Book3S HV: Disable HPT resizing on POWER9 for now", 2017-02-18),
now that HPT resizing works on POWER9.

On POWER9, when we pivot to the new HPT, we now call
kvmppc_setup_partition_table() to update the partition table in order
to make the hardware use the new HPT.

[paulus@ozlabs.org - added kvmppc_setup_partition_table() call,
 wrote commit message.]

Tested-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-02-09 15:36:36 +11:00
Radim Krčmář d2b9b2079e PPC KVM update for 4.16
- Allow HPT guests to run on a radix host on POWER9 v2.2 CPUs
   without requiring the complex thread synchronization that earlier
   CPU versions required.
 
 - A series from Ben Herrenschmidt to improve the handling of
   escalation interrupts with the XIVE interrupt controller.
 
 - Provide for the decrementer register to be copied across on
   migration.
 
 - Various minor cleanups and bugfixes.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJaYXViAAoJEJ2a6ncsY3GfDhgIAIDVBZH/Ftq7eJiUSxDpqyCQ
 DF/x7fNKzK/J33pu+3ntOI2gZsldExAy7vH2M27I4qLIkbI5y3vu4v8l3CDlS1LK
 9dKi72zg7baozoVF5mGUNm0B1sSvZiIQlC/kaami2aPTF1GcrJ561GthzfZwxENX
 TSLqOA4LkeUZh2tUsvbcUrPi6v+E4Em2lgacQcx2ioMblWz56sZu79VsUbSSw/a3
 P8+pIv7EbHw+TrOZMehjCbZkOdBeZ3IRLJsdlIAfe7y4vWME/5b9uVnQS/+XQj/B
 6f3rQrduGvF2P6GMjsm8gDkgE5oZ1zbKlgO4i5WApnu80MMLFlfEUN+GWuGJ95Q=
 =OjGs
 -----END PGP SIGNATURE-----

Merge tag 'kvm-ppc-next-4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc

PPC KVM update for 4.16

- Allow HPT guests to run on a radix host on POWER9 v2.2 CPUs
  without requiring the complex thread synchronization that earlier
  CPU versions required.

- A series from Ben Herrenschmidt to improve the handling of
  escalation interrupts with the XIVE interrupt controller.

- Provide for the decrementer register to be copied across on
  migration.

- Various minor cleanups and bugfixes.
2018-02-01 16:13:07 +01:00
Radim Krčmář 7bf14c28ee Merge branch 'x86/hyperv' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Topic branch for stable KVM clockource under Hyper-V.

Thanks to Christoffer Dall for resolving the ARM conflict.
2018-02-01 15:04:17 +01:00
Paul Mackerras 3214d01f13 KVM: PPC: Book3S: Provide information about hardware/firmware CVE workarounds
This adds a new ioctl, KVM_PPC_GET_CPU_CHAR, that gives userspace
information about the underlying machine's level of vulnerability
to the recently announced vulnerabilities CVE-2017-5715,
CVE-2017-5753 and CVE-2017-5754, and whether the machine provides
instructions to assist software to work around the vulnerabilities.

The ioctl returns two u64 words describing characteristics of the
CPU and required software behaviour respectively, plus two mask
words which indicate which bits have been filled in by the kernel,
for extensibility.  The bit definitions are the same as for the
new H_GET_CPU_CHARACTERISTICS hypercall.

There is also a new capability, KVM_CAP_PPC_GET_CPU_CHAR, which
indicates whether the new ioctl is available.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-01-19 15:17:01 +11:00
Paul Mackerras d27998185d Merge remote-tracking branch 'remotes/powerpc/topic/ppc-kvm' into kvm-ppc-next
This merges in the ppc-kvm topic branch of the powerpc tree to get
two patches which are prerequisites for the following patch series,
plus another patch which touches both powerpc and KVM code.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-01-19 12:09:57 +11:00
Paul Mackerras 5855564c8a KVM: PPC: Book3S HV: Enable migration of decrementer register
This adds a register identifier for use with the one_reg interface
to allow the decrementer expiry time to be read and written by
userspace.  The decrementer expiry time is in guest timebase units
and is equal to the sum of the decrementer and the guest timebase.
(The expiry time is used rather than the decrementer value itself
because the expiry time is not constantly changing, though the
decrementer value is, while the guest vcpu is not running.)

Without this, a guest vcpu migrated to a new host will see its
decrementer set to some random value.  On POWER8 and earlier, the
decrementer is 32 bits wide and counts down at 512MHz, so the
guest vcpu will potentially see no decrementer interrupts for up
to about 4 seconds, which will lead to a stall.  With POWER9, the
decrementer is now 56 bits side, so the stall can be much longer
(up to 2.23 years) and more noticeable.

To help work around the problem in cases where userspace has not been
updated to migrate the decrementer expiry time, we now set the
default decrementer expiry at vcpu creation time to the current time
rather than the maximum possible value.  This should mean an
immediate decrementer interrupt when a migrated vcpu starts
running.  In cases where the decrementer is 32 bits wide and more
than 4 seconds elapse between the creation of the vcpu and when it
first runs, the decrementer would have wrapped around to positive
values and there may still be a stall - but this is no worse than
the current situation.  In the large-decrementer case, we are sure
to get an immediate decrementer interrupt (assuming the time from
vcpu creation to first run is less than 2.23 years) and we thus
avoid a very long stall.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-01-16 11:54:45 +11:00
Paolo Bonzini 5cb0944c0c KVM: introduce kvm_arch_vcpu_async_ioctl
After the vcpu_load/vcpu_put pushdown, the handling of asynchronous VCPU
ioctl is already much clearer in that it is obvious that they bypass
vcpu_load and vcpu_put.

However, it is still not perfect in that the different state of the VCPU
mutex is still hidden in the caller.  Separate those ioctls into a new
function kvm_arch_vcpu_async_ioctl that returns -ENOIOCTLCMD for more
"traditional" synchronous ioctls.

Cc: James Hogan <jhogan@kernel.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Suggested-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14 09:26:59 +01:00