Commit Graph

127 Commits

Author SHA1 Message Date
Marc Zyngier
85bd0ba1ff arm/arm64: KVM: Add PSCI version selection API
Although we've implemented PSCI 0.1, 0.2 and 1.0, we expose either 0.1
or 1.0 to a guest, defaulting to the latest version of the PSCI
implementation that is compatible with the requested version. This is
no different from doing a firmware upgrade on KVM.

But in order to give a chance to hypothetical badly implemented guests
that would have a fit by discovering something other than PSCI 0.2,
let's provide a new API that allows userspace to pick one particular
version of the API.

This is implemented as a new class of "firmware" registers, where
we expose the PSCI version. This allows the PSCI version to be
save/restored as part of a guest migration, and also set to
any supported version if the guest requires it.

Cc: stable@vger.kernel.org #4.16
Reviewed-by: Christoffer Dall <cdall@kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-04-20 16:32:23 +01:00
Christoffer Dall
d47533dab9 KVM: arm64: Introduce framework for accessing deferred sysregs
We are about to defer saving and restoring some groups of system
registers to vcpu_put and vcpu_load on supported systems.  This means
that we need some infrastructure to access system registes which
supports either accessing the memory backing of the register or directly
accessing the system registers, depending on the state of the system
when we access the register.

We do this by defining read/write accessor functions, which can handle
both "immediate" and "deferrable" system registers.  Immediate registers
are always saved/restored in the world-switch path, but deferrable
registers are only saved/restored in vcpu_put/vcpu_load when supported
and sysregs_loaded_on_cpu will be set in that case.

Note that we don't use the deferred mechanism yet in this patch, but only
introduce infrastructure.  This is to improve convenience of review in
the subsequent patches where it is clear which registers become
deferred.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 10:53:17 +00:00
Christoffer Dall
8d404c4c24 KVM: arm64: Rewrite system register accessors to read/write functions
Currently we access the system registers array via the vcpu_sys_reg()
macro.  However, we are about to change the behavior to some times
modify the register file directly, so let's change this to two
primitives:

 * Accessor macros vcpu_write_sys_reg() and vcpu_read_sys_reg()
 * Direct array access macro __vcpu_sys_reg()

The accessor macros should be used in places where the code needs to
access the currently loaded VCPU's state as observed by the guest.  For
example, when trapping on cache related registers, a write to a system
register should go directly to the VCPU version of the register.

The direct array access macro can be used in places where the VCPU is
known to never be running (for example userspace access) or for
registers which are never context switched (for example all the PMU
system registers).

This rewrites all users of vcpu_sys_regs to one of the macros described
above.

No functional change.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 10:53:16 +00:00
Christoffer Dall
52f6c4f021 KVM: arm64: Change 32-bit handling of VM system registers
We currently handle 32-bit accesses to trapped VM system registers using
the 32-bit index into the coproc array on the vcpu structure, which is a
union of the coproc array and the sysreg array.

Since all the 32-bit coproc indices are created to correspond to the
architectural mapping between 64-bit system registers and 32-bit
coprocessor registers, and because the AArch64 system registers are the
double in size of the AArch32 coprocessor registers, we can always find
the system register entry that we must update by dividing the 32-bit
coproc index by 2.

This is going to make our lives much easier when we have to start
accessing system registers that use deferred save/restore and might
have to be read directly from the physical CPU.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 10:53:16 +00:00
Christoffer Dall
3f5c90b890 KVM: arm64: Introduce VHE-specific kvm_vcpu_run
So far this is mostly (see below) a copy of the legacy non-VHE switch
function, but we will start reworking these functions in separate
directions to work on VHE and non-VHE in the most optimal way in later
patches.

The only difference after this patch between the VHE and non-VHE run
functions is that we omit the branch-predictor variant-2 hardening for
QC Falkor CPUs, because this workaround is specific to a series of
non-VHE ARMv8.0 CPUs.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 10:53:13 +00:00
Christoffer Dall
bc192ceec3 KVM: arm/arm64: Add kvm_vcpu_load_sysregs and kvm_vcpu_put_sysregs
As we are about to move a bunch of save/restore logic for VHE kernels to
the load and put functions, we need some infrastructure to do this.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 10:53:11 +00:00
Christoffer Dall
3df59d8dd3 KVM: arm/arm64: Get rid of vcpu->arch.irq_lines
We currently have a separate read-modify-write of the HCR_EL2 on entry
to the guest for the sole purpose of setting the VF and VI bits, if set.
Since this is most rarely the case (only when using userspace IRQ chip
and interrupts are in flight), let's get rid of this operation and
instead modify the bits in the vcpu->arch.hcr[_el2] directly when
needed.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 10:53:10 +00:00
Christoffer Dall
4464e210de KVM: arm64: Avoid storing the vcpu pointer on the stack
We already have the percpu area for the host cpu state, which points to
the VCPU, so there's no need to store the VCPU pointer on the stack on
every context switch.  We can be a little more clever and just use
tpidr_el2 for the percpu offset and load the VCPU pointer from the host
context.

This has the benefit of being able to retrieve the host context even
when our stack is corrupted, and it has a potential performance benefit
because we trade a store plus a load for an mrs and a load on a round
trip to the guest.

This does require us to calculate the percpu offset without including
the offset from the kernel mapping of the percpu array to the linear
mapping of the array (which is what we store in tpidr_el1), because a
PC-relative generated address in EL2 is already giving us the hyp alias
of the linear mapping of a kernel address.  We do this in
__cpu_init_hyp_mode() by using kvm_ksym_ref().

The code that accesses ESR_EL2 was previously using an alternative to
use the _EL1 accessor on VHE systems, but this was actually unnecessary
as the _EL1 accessor aliases the ESR_EL2 register on VHE, and the _EL2
accessor does the same thing on both systems.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 10:53:09 +00:00
Linus Torvalds
15303ba5d1 KVM changes for 4.16
ARM:
 - Include icache invalidation optimizations, improving VM startup time
 
 - Support for forwarded level-triggered interrupts, improving
   performance for timers and passthrough platform devices
 
 - A small fix for power-management notifiers, and some cosmetic changes
 
 PPC:
 - Add MMIO emulation for vector loads and stores
 
 - Allow HPT guests to run on a radix host on POWER9 v2.2 CPUs without
   requiring the complex thread synchronization of older CPU versions
 
 - Improve the handling of escalation interrupts with the XIVE interrupt
   controller
 
 - Support decrement register migration
 
 - Various cleanups and bugfixes.
 
 s390:
 - Cornelia Huck passed maintainership to Janosch Frank
 
 - Exitless interrupts for emulated devices
 
 - Cleanup of cpuflag handling
 
 - kvm_stat counter improvements
 
 - VSIE improvements
 
 - mm cleanup
 
 x86:
 - Hypervisor part of SEV
 
 - UMIP, RDPID, and MSR_SMI_COUNT emulation
 
 - Paravirtualized TLB shootdown using the new KVM_VCPU_PREEMPTED bit
 
 - Allow guests to see TOPOEXT, GFNI, VAES, VPCLMULQDQ, and more AVX512
   features
 
 - Show vcpu id in its anonymous inode name
 
 - Many fixes and cleanups
 
 - Per-VCPU MSR bitmaps (already merged through x86/pti branch)
 
 - Stable KVM clock when nesting on Hyper-V (merged through x86/hyperv)
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Merge tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Radim Krčmář:
 "ARM:

   - icache invalidation optimizations, improving VM startup time

   - support for forwarded level-triggered interrupts, improving
     performance for timers and passthrough platform devices

   - a small fix for power-management notifiers, and some cosmetic
     changes

  PPC:

   - add MMIO emulation for vector loads and stores

   - allow HPT guests to run on a radix host on POWER9 v2.2 CPUs without
     requiring the complex thread synchronization of older CPU versions

   - improve the handling of escalation interrupts with the XIVE
     interrupt controller

   - support decrement register migration

   - various cleanups and bugfixes.

  s390:

   - Cornelia Huck passed maintainership to Janosch Frank

   - exitless interrupts for emulated devices

   - cleanup of cpuflag handling

   - kvm_stat counter improvements

   - VSIE improvements

   - mm cleanup

  x86:

   - hypervisor part of SEV

   - UMIP, RDPID, and MSR_SMI_COUNT emulation

   - paravirtualized TLB shootdown using the new KVM_VCPU_PREEMPTED bit

   - allow guests to see TOPOEXT, GFNI, VAES, VPCLMULQDQ, and more
     AVX512 features

   - show vcpu id in its anonymous inode name

   - many fixes and cleanups

   - per-VCPU MSR bitmaps (already merged through x86/pti branch)

   - stable KVM clock when nesting on Hyper-V (merged through
     x86/hyperv)"

* tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (197 commits)
  KVM: PPC: Book3S: Add MMIO emulation for VMX instructions
  KVM: PPC: Book3S HV: Branch inside feature section
  KVM: PPC: Book3S HV: Make HPT resizing work on POWER9
  KVM: PPC: Book3S HV: Fix handling of secondary HPTEG in HPT resizing code
  KVM: PPC: Book3S PR: Fix broken select due to misspelling
  KVM: x86: don't forget vcpu_put() in kvm_arch_vcpu_ioctl_set_sregs()
  KVM: PPC: Book3S PR: Fix svcpu copying with preemption enabled
  KVM: PPC: Book3S HV: Drop locks before reading guest memory
  kvm: x86: remove efer_reload entry in kvm_vcpu_stat
  KVM: x86: AMD Processor Topology Information
  x86/kvm/vmx: do not use vm-exit instruction length for fast MMIO when running nested
  kvm: embed vcpu id to dentry of vcpu anon inode
  kvm: Map PFN-type memory regions as writable (if possible)
  x86/kvm: Make it compile on 32bit and with HYPYERVISOR_GUEST=n
  KVM: arm/arm64: Fixup userspace irqchip static key optimization
  KVM: arm/arm64: Fix userspace_irqchip_in_use counting
  KVM: arm/arm64: Fix incorrect timer_is_pending logic
  MAINTAINERS: update KVM/s390 maintainers
  MAINTAINERS: add Halil as additional vfio-ccw maintainer
  MAINTAINERS: add David as a reviewer for KVM/s390
  ...
2018-02-10 13:16:35 -08:00
Marc Zyngier
6167ec5c91 arm64: KVM: Report SMCCC_ARCH_WORKAROUND_1 BP hardening support
A new feature of SMCCC 1.1 is that it offers firmware-based CPU
workarounds. In particular, SMCCC_ARCH_WORKAROUND_1 provides
BP hardening for CVE-2017-5715.

If the host has some mitigation for this issue, report that
we deal with it using SMCCC_ARCH_WORKAROUND_1, as we apply the
host workaround on every guest exit.

Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06 22:54:05 +00:00
James Morse
0067df413b KVM: arm64: Handle RAS SErrors from EL2 on guest exit
We expect to have firmware-first handling of RAS SErrors, with errors
notified via an APEI method. For systems without firmware-first, add
some minimal handling to KVM.

There are two ways KVM can take an SError due to a guest, either may be a
RAS error: we exit the guest due to an SError routed to EL2 by HCR_EL2.AMO,
or we take an SError from EL2 when we unmask PSTATE.A from __guest_exit.

The current SError from EL2 code unmasks SError and tries to fence any
pending SError into a single instruction window. It then leaves SError
unmasked.

With the v8.2 RAS Extensions we may take an SError for a 'corrected'
error, but KVM is only able to handle SError from EL2 if they occur
during this single instruction window...

The RAS Extensions give us a new instruction to synchronise and
consume SErrors. The RAS Extensions document (ARM DDI0587),
'2.4.1 ESB and Unrecoverable errors' describes ESB as synchronising
SError interrupts generated by 'instructions, translation table walks,
hardware updates to the translation tables, and instruction fetches on
the same PE'. This makes ESB equivalent to KVMs existing
'dsb, mrs-daifclr, isb' sequence.

Use the alternatives to synchronise and consume any SError using ESB
instead of unmasking and taking the SError. Set ARM_EXIT_WITH_SERROR_BIT
in the exit_code so that we can restart the vcpu if it turns out this
SError has no impact on the vcpu.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-16 15:09:36 +00:00
James Morse
3368bd8097 KVM: arm64: Handle RAS SErrors from EL1 on guest exit
We expect to have firmware-first handling of RAS SErrors, with errors
notified via an APEI method. For systems without firmware-first, add
some minimal handling to KVM.

There are two ways KVM can take an SError due to a guest, either may be a
RAS error: we exit the guest due to an SError routed to EL2 by HCR_EL2.AMO,
or we take an SError from EL2 when we unmask PSTATE.A from __guest_exit.

For SError that interrupt a guest and are routed to EL2 the existing
behaviour is to inject an impdef SError into the guest.

Add code to handle RAS SError based on the ESR. For uncontained and
uncategorized errors arm64_is_fatal_ras_serror() will panic(), these
errors compromise the host too. All other error types are contained:
For the fatal errors the vCPU can't make progress, so we inject a virtual
SError. We ignore contained errors where we can make progress as if
we're lucky, we may not hit them again.

If only some of the CPUs support RAS the guest will see the cpufeature
sanitised version of the id registers, but we may still take RAS SError
on this CPU. Move the SError handling out of handle_exit() into a new
handler that runs before we can be preempted. This allows us to use
this_cpu_has_cap(), via arm64_is_ras_serror().

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-16 15:09:13 +00:00
James Morse
c773ae2b34 KVM: arm64: Save/Restore guest DISR_EL1
If we deliver a virtual SError to the guest, the guest may defer it
with an ESB instruction. The guest reads the deferred value via DISR_EL1,
but the guests view of DISR_EL1 is re-mapped to VDISR_EL2 when HCR_EL2.AMO
is set.

Add the KVM code to save/restore VDISR_EL2, and make it accessible to
userspace as DISR_EL1.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-16 15:08:52 +00:00
James Morse
4715c14bc1 KVM: arm64: Set an impdef ESR for Virtual-SError using VSESR_EL2.
Prior to v8.2's RAS Extensions, the HCR_EL2.VSE 'virtual SError' feature
generated an SError with an implementation defined ESR_EL1.ISS, because we
had no mechanism to specify the ESR value.

On Juno this generates an all-zero ESR, the most significant bit 'ISV'
is clear indicating the remainder of the ISS field is invalid.

With the RAS Extensions we have a mechanism to specify this value, and the
most significant bit has a new meaning: 'IDS - Implementation Defined
Syndrome'. An all-zero SError ESR now means: 'RAS error: Uncategorized'
instead of 'no valid ISS'.

Add KVM support for the VSESR_EL2 register to specify an ESR value when
HCR_EL2.VSE generates a virtual SError. Change kvm_inject_vabt() to
specify an implementation-defined value.

We only need to restore the VSESR_EL2 value when HCR_EL2.VSE is set, KVM
save/restores this bit during __{,de}activate_traps() and hardware clears the
bit once the guest has consumed the virtual-SError.

Future patches may add an API (or KVM CAP) to pend a virtual SError with
a specified ESR.

Cc: Dongjiu Geng <gengdongjiu@huawei.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-16 15:08:41 +00:00
James Morse
4f5abad9e8 KVM: arm/arm64: mask/unmask daif around VHE guests
Non-VHE systems take an exception to EL2 in order to world-switch into the
guest. When returning from the guest KVM implicitly restores the DAIF
flags when it returns to the kernel at EL1.

With VHE none of this exception-level jumping happens, so KVMs
world-switch code is exposed to the host kernel's DAIF values, and KVM
spills the guest-exit DAIF values back into the host kernel.
On entry to a guest we have Debug and SError exceptions unmasked, KVM
has switched VBAR but isn't prepared to handle these. On guest exit
Debug exceptions are left disabled once we return to the host and will
stay this way until we enter user space.

Add a helper to mask/unmask DAIF around VHE guests. The unmask can only
happen after the hosts VBAR value has been synchronised by the isb in
__vhe_hyp_call (via kvm_call_hyp()). Masking could be as late as
setting KVMs VBAR value, but is kept here for symmetry.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-16 15:08:24 +00:00
James Morse
c97e166e54 KVM: arm64: Change hyp_panic()s dependency on tpidr_el2
Make tpidr_el2 a cpu-offset for per-cpu variables in the same way the
host uses tpidr_el1. This lets tpidr_el{1,2} have the same value, and
on VHE they can be the same register.

KVM calls hyp_panic() when anything unexpected happens. This may occur
while a guest owns the EL1 registers. KVM stashes the vcpu pointer in
tpidr_el2, which it uses to find the host context in order to restore
the host EL1 registers before parachuting into the host's panic().

The host context is a struct kvm_cpu_context allocated in the per-cpu
area, and mapped to hyp. Given the per-cpu offset for this CPU, this is
easy to find. Change hyp_panic() to take a pointer to the
struct kvm_cpu_context. Wrap these calls with an asm function that
retrieves the struct kvm_cpu_context from the host's per-cpu area.

Copy the per-cpu offset from the hosts tpidr_el1 into tpidr_el2 during
kvm init. (Later patches will make this unnecessary for VHE hosts)

We print out the vcpu pointer as part of the panic message. Add a back
reference to the 'running vcpu' in the host cpu context to preserve this.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-13 10:44:22 +00:00
Christoffer Dall
61bbe38027 KVM: arm/arm64: Avoid work when userspace iqchips are not used
We currently check if the VM has a userspace irqchip in several places
along the critical path, and if so, we do some work which is only
required for having an irqchip in userspace.  This is unfortunate, as we
could avoid doing any work entirely, if we didn't have to support
irqchip in userspace.

Realizing the userspace irqchip on ARM is mostly a developer or hobby
feature, and is unlikely to be used in servers or other scenarios where
performance is a priority, we can use a refcounted static key to only
check the irqchip configuration when we have at least one VM that uses
an irqchip in userspace.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-02 10:05:46 +01:00
Alex Bennée
696673d192 KVM: arm/arm64: debug: Introduce helper for single-step
After emulating instructions we may want return to user-space to handle
single-step debugging. Introduce a helper function, which, if
single-step is enabled, sets the run structure for return and returns
true.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-29 16:46:19 +01:00
Dave Martin
17eed27b02 arm64/sve: KVM: Prevent guests from using SVE
Until KVM has full SVE support, guests must not be allowed to
execute SVE instructions.

This patch enables the necessary traps, and also ensures that the
traps are disabled again on exit from the guest so that the host
can still use SVE if it wants to.

On guest exit, high bits of the SVE Zn registers may have been
clobbered as a side-effect the execution of FPSIMD instructions in
the guest.  The existing KVM host FPSIMD restore code is not
sufficient to restore these bits, so this patch explicitly marks
the CPU as not containing cached vector state for any task, thus
forcing a reload on the next return to userspace.  This is an
interim measure, in advance of adding full SVE awareness to KVM.

This marking of cached vector state in the CPU as invalid is done
using __this_cpu_write(fpsimd_last_state, NULL) in fpsimd.c.  Due
to the repeated use of this rather obscure operation, it makes
sense to factor it out as a separate helper with a clearer name.
This patch factors it out as fpsimd_flush_cpu_state(), and ports
all callers to use it.

As a side effect of this refactoring, a this_cpu_write() in
fpsimd_cpu_pm_notifier() is changed to __this_cpu_write().  This
should be fine, since cpu_pm_enter() is supposed to be called only
with interrupts disabled.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-11-03 15:24:19 +00:00
Jérôme Glisse
fb1522e099 KVM: update to new mmu_notifier semantic v2
Calls to mmu_notifier_invalidate_page() were replaced by calls to
mmu_notifier_invalidate_range() and are now bracketed by calls to
mmu_notifier_invalidate_range_start()/end()

Remove now useless invalidate_page callback.

Changed since v1 (Linus Torvalds)
    - remove now useless kvm_arch_mmu_notifier_invalidate_page()

Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Tested-by: Mike Galbraith <efault@gmx.de>
Tested-by: Adam Borowski <kilobyte@angband.pl>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: kvm@vger.kernel.org
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-31 16:13:00 -07:00
Paolo Bonzini
04a7ea04d5 KVM/ARM updates for 4.13
- 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
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Merge tag 'kvmarm-for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/ARM updates for 4.13

- 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

Conflicts:
	arch/s390/include/asm/kvm_host.h
2017-06-30 12:38:26 +02:00
Andrew Jones
325f9c649c KVM: arm/arm64: use vcpu requests for irq injection
Don't use request-less VCPU kicks when injecting IRQs, as a VCPU
kick meant to trigger the interrupt injection could be sent while
the VCPU is outside guest mode, which means no IPI is sent, and
after it has called kvm_vgic_flush_hwstate(), meaning it won't see
the updated GIC state until its next exit some time later for some
other reason.  The receiving VCPU only needs to check this request
in VCPU RUN to handle it.  By checking it, if it's pending, a
memory barrier will be issued that ensures all state is visible.
See "Ensuring Requests Are Seen" of
Documentation/virtual/kvm/vcpu-requests.rst

Signed-off-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-06-04 16:53:56 +02:00
Andrew Jones
7b244e2be6 KVM: arm/arm64: change exit request to sleep request
A request called EXIT is too generic. All requests are meant to cause
exits, but different requests have different flags. Let's not make
it difficult to decide if the EXIT request is correct for some case
by just always providing unique requests for each case. This patch
changes EXIT to SLEEP, because that's what the request is asking the
VCPU to do.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-06-04 16:53:55 +02:00
Andrew Jones
2387149ead KVM: improve arch vcpu request defining
Marc Zyngier suggested that we define the arch specific VCPU request
base, rather than requiring each arch to remember to start from 8.
That suggestion, along with Radim Krcmar's recent VCPU request flag
addition, snowballed into defining something of an arch VCPU request
defining API.

No functional change.

(Looks like x86 is running out of arch VCPU request bits.  Maybe
 someday we'll need to extend to 64.)

Signed-off-by: Andrew Jones <drjones@redhat.com>
Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-06-04 16:53:00 +02:00
Christoffer Dall
abd7229626 KVM: arm/arm64: Simplify active_change_prepare and plug race
We don't need to stop a specific VCPU when changing the active state,
because private IRQs can only be modified by a running VCPU for the
VCPU itself and it is therefore already stopped.

However, it is also possible for two VCPUs to be modifying the active
state of SPIs at the same time, which can cause the thread being stuck
in the loop that checks other VCPU threads for a potentially very long
time, or to modify the active state of a running VCPU.  Fix this by
serializing all accesses to setting and clearing the active state of
interrupts using the KVM mutex.

Reported-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
2017-05-23 12:48:22 +02:00
Mark Rutland
63a1e1c95e arm64/cpufeature: don't use mutex in bringup path
Currently, cpus_set_cap() calls static_branch_enable_cpuslocked(), which
must take the jump_label mutex.

We call cpus_set_cap() in the secondary bringup path, from the idle
thread where interrupts are disabled. Taking a mutex in this path "is a
NONO" regardless of whether it's contended, and something we must avoid.
We didn't spot this until recently, as ___might_sleep() won't warn for
this case until all CPUs have been brought up.

This patch avoids taking the mutex in the secondary bringup path. The
poking of static keys is deferred until enable_cpu_capabilities(), which
runs in a suitable context on the boot CPU. To account for the static
keys being set later, cpus_have_const_cap() is updated to use another
static key to check whether the const cap keys have been initialised,
falling back to the caps bitmap until this is the case.

This means that users of cpus_have_const_cap() gain should only gain a
single additional NOP in the fast path once the const caps are
initialised, but should always see the current cap value.

The hyp code should never dereference the caps array, since the caps are
initialized before we run the module initcall to initialise hyp. A check
is added to the hyp init code to document this requirement.

This change will sidestep a number of issues when the upcoming hotplug
locking rework is merged.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyniger <marc.zyngier@arm.com>
Reviewed-by: Suzuki Poulose <suzuki.poulose@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Sewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-05-17 17:00:29 +01:00
Paolo Bonzini
c24a7be211 KVM/ARM Changes for v4.12.
Changes include:
  - Using the common sysreg definitions between KVM and arm64
  - Improved hyp-stub implementation with support for kexec and kdump on the 32-bit side
  - Proper PMU exception handling
  - Performance improvements of our GIC handling
  - Support for irqchip in userspace with in-kernel arch-timers and PMU support
  - A fix for a race condition in our PSCI code
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Merge tag 'kvm-arm-for-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/ARM Changes for v4.12.

Changes include:
 - Using the common sysreg definitions between KVM and arm64
 - Improved hyp-stub implementation with support for kexec and kdump on the 32-bit side
 - Proper PMU exception handling
 - Performance improvements of our GIC handling
 - Support for irqchip in userspace with in-kernel arch-timers and PMU support
 - A fix for a race condition in our PSCI code

Conflicts:
	Documentation/virtual/kvm/api.txt
	include/uapi/linux/kvm.h
2017-04-27 17:33:14 +02:00
Paolo Bonzini
7a97cec26b KVM: mark requests that need synchronization
kvm_make_all_requests() provides a synchronization that waits until all
kicked VCPUs have acknowledged the kick.  This is important for
KVM_REQ_MMU_RELOAD as it prevents freeing while lockless paging is
underway.

This patch adds the synchronization property into all requests that are
currently being used with kvm_make_all_requests() in order to preserve
the current behavior and only introduce a new framework.  Removing it
from requests where it is not necessary is left for future patches.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-04-27 14:36:44 +02:00
Radim Krčmář
930f7fd6da KVM: mark requests that do not need a wakeup
Some operations must ensure that the guest is not running with stale
data, but if the guest is halted, then the update can wait until another
event happens.  kvm_make_all_requests() currently doesn't wake up, so we
can mark all requests used with it.

First 8 bits were arbitrarily reserved for request numbers.

Most uses of requests have the request type as a constant, so a compiler
will optimize the '&'.

An alternative would be to have an inline function that would return
whether the request needs a wake-up or not, but I like this one better
even though it might produce worse assembly.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-04-27 14:13:57 +02:00
Marc Zyngier
0fb265930d arm/arm64: KVM: Use __hyp_reset_vectors() directly
__cpu_reset_hyp_mode doesn't need to be passed any argument now,
as the hyp-stub implementations are self-contained, and is now
reduced to just calling __hyp_reset_vectors(). Let's drop the
wrapper and use the stub hypercall directly.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-04-09 07:49:32 -07:00
Marc Zyngier
4adb1341c7 arm64: KVM: Convert __cpu_reset_hyp_mode to using __hyp_reset_vectors
We are now able to use the hyp stub to reset HYP mode. Time to
kiss __kvm_hyp_reset goodbye, and use __hyp_reset_vectors.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-04-09 07:49:22 -07:00
Paolo Bonzini
4b4357e025 kvm: make KVM_COALESCED_MMIO_PAGE_OFFSET public
Its value has never changed; we might as well make it part of the ABI instead
of using the return value of KVM_CHECK_EXTENSION(KVM_CAP_COALESCED_MMIO).

Because PPC does not always make MMIO available, the code has to be made
dependent on CONFIG_KVM_MMIO rather than KVM_COALESCED_MMIO_PAGE_OFFSET.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-04-07 16:49:01 +02:00
Linu Cherian
955a3fc6d2 KVM: arm64: Increase number of user memslots to 512
Having only 32 memslots is a real constraint for the maximum
number of PCI devices that can be assigned to a single guest.
Assuming each PCI device/virtual function having two memory BAR
regions, we could assign only 15 devices/virtual functions to a
guest.

Hence increase KVM_USER_MEM_SLOTS to 512 as done in other archs like
powerpc.

Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Linu Cherian <linu.cherian@cavium.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-03-09 09:13:50 +00:00
Linu Cherian
3e92f94a3b KVM: arm/arm64: Remove KVM_PRIVATE_MEM_SLOTS definition that are unused
arm/arm64 architecture doesnt use private memslots, hence removing
KVM_PRIVATE_MEM_SLOTS macro definition.

Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Linu Cherian <linu.cherian@cavium.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-03-09 09:13:45 +00:00
Linus Torvalds
fd7e9a8834 4.11 is going to be a relatively large release for KVM, with a little over
200 commits and noteworthy changes for most architectures.
 
 * ARM:
 - GICv3 save/restore
 - cache flushing fixes
 - working MSI injection for GICv3 ITS
 - physical timer emulation
 
 * MIPS:
 - various improvements under the hood
 - support for SMP guests
 - a large rewrite of MMU emulation.  KVM MIPS can now use MMU notifiers
 to support copy-on-write, KSM, idle page tracking, swapping, ballooning
 and everything else.  KVM_CAP_READONLY_MEM is also supported, so that
 writes to some memory regions can be treated as MMIO.  The new MMU also
 paves the way for hardware virtualization support.
 
 * PPC:
 - support for POWER9 using the radix-tree MMU for host and guest
 - resizable hashed page table
 - bugfixes.
 
 * s390: expose more features to the guest
 - more SIMD extensions
 - instruction execution protection
 - ESOP2
 
 * x86:
 - improved hashing in the MMU
 - faster PageLRU tracking for Intel CPUs without EPT A/D bits
 - some refactoring of nested VMX entry/exit code, preparing for live
 migration support of nested hypervisors
 - expose yet another AVX512 CPUID bit
 - host-to-guest PTP support
 - refactoring of interrupt injection, with some optimizations thrown in
 and some duct tape removed.
 - remove lazy FPU handling
 - optimizations of user-mode exits
 - optimizations of vcpu_is_preempted() for KVM guests
 
 * generic:
 - alternative signaling mechanism that doesn't pound on tsk->sighand->siglock
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "4.11 is going to be a relatively large release for KVM, with a little
  over 200 commits and noteworthy changes for most architectures.

  ARM:
   - GICv3 save/restore
   - cache flushing fixes
   - working MSI injection for GICv3 ITS
   - physical timer emulation

  MIPS:
   - various improvements under the hood
   - support for SMP guests
   - a large rewrite of MMU emulation. KVM MIPS can now use MMU
     notifiers to support copy-on-write, KSM, idle page tracking,
     swapping, ballooning and everything else. KVM_CAP_READONLY_MEM is
     also supported, so that writes to some memory regions can be
     treated as MMIO. The new MMU also paves the way for hardware
     virtualization support.

  PPC:
   - support for POWER9 using the radix-tree MMU for host and guest
   - resizable hashed page table
   - bugfixes.

  s390:
   - expose more features to the guest
   - more SIMD extensions
   - instruction execution protection
   - ESOP2

  x86:
   - improved hashing in the MMU
   - faster PageLRU tracking for Intel CPUs without EPT A/D bits
   - some refactoring of nested VMX entry/exit code, preparing for live
     migration support of nested hypervisors
   - expose yet another AVX512 CPUID bit
   - host-to-guest PTP support
   - refactoring of interrupt injection, with some optimizations thrown
     in and some duct tape removed.
   - remove lazy FPU handling
   - optimizations of user-mode exits
   - optimizations of vcpu_is_preempted() for KVM guests

  generic:
   - alternative signaling mechanism that doesn't pound on
     tsk->sighand->siglock"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (195 commits)
  x86/kvm: Provide optimized version of vcpu_is_preempted() for x86-64
  x86/paravirt: Change vcp_is_preempted() arg type to long
  KVM: VMX: use correct vmcs_read/write for guest segment selector/base
  x86/kvm/vmx: Defer TR reload after VM exit
  x86/asm/64: Drop __cacheline_aligned from struct x86_hw_tss
  x86/kvm/vmx: Simplify segment_base()
  x86/kvm/vmx: Get rid of segment_base() on 64-bit kernels
  x86/kvm/vmx: Don't fetch the TSS base from the GDT
  x86/asm: Define the kernel TSS limit in a macro
  kvm: fix page struct leak in handle_vmon
  KVM: PPC: Book3S HV: Disable HPT resizing on POWER9 for now
  KVM: Return an error code only as a constant in kvm_get_dirty_log()
  KVM: Return an error code only as a constant in kvm_get_dirty_log_protect()
  KVM: Return directly after a failed copy_from_user() in kvm_vm_compat_ioctl()
  KVM: x86: remove code for lazy FPU handling
  KVM: race-free exit from KVM_RUN without POSIX signals
  KVM: PPC: Book3S HV: Turn "KVM guest htab" message into a debug message
  KVM: PPC: Book3S PR: Ratelimit copy data failure error messages
  KVM: Support vCPU-based gfn->hva cache
  KVM: use separate generations for each address space
  ...
2017-02-22 18:22:53 -08:00
Jintack Lim
90de943a43 KVM: arm/arm64: Move cntvoff to each timer context
Make cntvoff per each timer context. This is helpful to abstract kvm
timer functions to work with timer context without considering timer
types (e.g. physical timer or virtual timer).

This also would pave the way for ever doing adjustments of the cntvoff
on a per-CPU basis if that should ever make sense.

Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-08 15:13:33 +00:00
Will Deacon
f85279b4bd arm64: KVM: Save/restore the host SPE state when entering/leaving a VM
The SPE buffer is virtually addressed, using the page tables of the CPU
MMU. Unusually, this means that the EL0/1 page table may be live whilst
we're executing at EL2 on non-VHE configurations. When VHE is in use,
we can use the same property to profile the guest behind its back.

This patch adds the relevant disabling and flushing code to KVM so that
the host can make use of SPE without corrupting guest memory, and any
attempts by a guest to use SPE will result in a trap.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Alex Bennée <alex.bennee@linaro.org>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-02-02 18:33:01 +00:00
Marc Zyngier
94d0e5980d arm/arm64: KVM: Perform local TLB invalidation when multiplexing vcpus on a single CPU
Architecturally, TLBs are private to the (physical) CPU they're
associated with. But when multiple vcpus from the same VM are
being multiplexed on the same CPU, the TLBs are not private
to the vcpus (and are actually shared across the VMID).

Let's consider the following scenario:

- vcpu-0 maps PA to VA
- vcpu-1 maps PA' to VA

If run on the same physical CPU, vcpu-1 can hit TLB entries generated
by vcpu-0 accesses, and access the wrong physical page.

The solution to this is to keep a per-VM map of which vcpu ran last
on each given physical CPU, and invalidate local TLBs when switching
to a different vcpu from the same VM.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-11-04 17:56:28 +00:00
Suraj Jitindar Singh
8a7e75d47b KVM: Add provisioning for ulong vm stats and u64 vcpu stats
vms and vcpus have statistics associated with them which can be viewed
within the debugfs. Currently it is assumed within the vcpu_stat_get() and
vm_stat_get() functions that all of these statistics are represented as
u32s, however the next patch adds some u64 vcpu statistics.

Change all vcpu statistics to u64 and modify vcpu_stat_get() accordingly.
Since vcpu statistics are per vcpu, they will only be updated by a single
vcpu at a time so this shouldn't present a problem on 32-bit machines
which can't atomically increment 64-bit numbers. However vm statistics
could potentially be updated by multiple vcpus from that vm at a time.
To avoid the overhead of atomics make all vm statistics ulong such that
they are 64-bit on 64-bit systems where they can be atomically incremented
and are 32-bit on 32-bit systems which may not be able to atomically
increment 64-bit numbers. Modify vm_stat_get() to expect ulongs.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2016-09-08 12:25:37 +10:00
Andre Przywara
b46f01ce4d KVM: arm/arm64: Extend arch CAP checks to allow per-VM capabilities
KVM capabilities can be a per-VM property, though ARM/ARM64 currently
does not pass on the VM pointer to the architecture specific
capability handlers.
Add a "struct kvm*" parameter to those function to later allow proper
per-VM capability reporting.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:10:31 +01:00
Marc Zyngier
e537ecd7ef arm: KVM: Allow hyp teardown
So far, KVM was getting in the way of kexec on 32bit (and the arm64
kexec hackers couldn't be bothered to fix it on 32bit...).

With simpler page tables, tearing KVM down becomes very easy, so
let's just do it.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
12fda8123d arm/arm64: KVM: Drop boot_pgd
Since we now only have one set of page tables, the concept of
boot_pgd is useless and can be removed. We still keep it as
an element of the "extended idmap" thing.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
3421e9d88d arm64: KVM: Simplify HYP init/teardown
Now that we only have the "merged page tables" case to deal with,
there is a bunch of things we can simplify in the HYP code (both
at init and teardown time).

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Linus Torvalds
e28e909c36 - move kvm_stat tool from QEMU repo into tools/kvm/kvm_stat
(kvm_stat had nothing to do with QEMU in the first place -- the tool
    only interprets debugfs)
 - expose per-vm statistics in debugfs and support them in kvm_stat
   (KVM always collected per-vm statistics, but they were summarised into
    global statistics)
 
 x86:
  - fix dynamic APICv (VMX was improperly configured and a guest could
    access host's APIC MSRs, CVE-2016-4440)
  - minor fixes
 
 ARM changes from Christoffer Dall:
  "This set of changes include the new vgic, which is a reimplementation
   of our horribly broken legacy vgic implementation.  The two
   implementations will live side-by-side (with the new being the
   configured default) for one kernel release and then we'll remove the
   legacy one.
 
   Also fixes a non-critical issue with virtual abort injection to
   guests."
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull second batch of KVM updates from Radim Krčmář:
 "General:

   - move kvm_stat tool from QEMU repo into tools/kvm/kvm_stat (kvm_stat
     had nothing to do with QEMU in the first place -- the tool only
     interprets debugfs)

   - expose per-vm statistics in debugfs and support them in kvm_stat
     (KVM always collected per-vm statistics, but they were summarised
     into global statistics)

  x86:

   - fix dynamic APICv (VMX was improperly configured and a guest could
     access host's APIC MSRs, CVE-2016-4440)

   - minor fixes

  ARM changes from Christoffer Dall:

   - new vgic reimplementation of our horribly broken legacy vgic
     implementation.  The two implementations will live side-by-side
     (with the new being the configured default) for one kernel release
     and then we'll remove the legacy one.

   - fix for a non-critical issue with virtual abort injection to guests"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (70 commits)
  tools: kvm_stat: Add comments
  tools: kvm_stat: Introduce pid monitoring
  KVM: Create debugfs dir and stat files for each VM
  MAINTAINERS: Add kvm tools
  tools: kvm_stat: Powerpc related fixes
  tools: Add kvm_stat man page
  tools: Add kvm_stat vm monitor script
  kvm:vmx: more complete state update on APICv on/off
  KVM: SVM: Add more SVM_EXIT_REASONS
  KVM: Unify traced vector format
  svm: bitwise vs logical op typo
  KVM: arm/arm64: vgic-new: Synchronize changes to active state
  KVM: arm/arm64: vgic-new: enable build
  KVM: arm/arm64: vgic-new: implement mapped IRQ handling
  KVM: arm/arm64: vgic-new: Wire up irqfd injection
  KVM: arm/arm64: vgic-new: Add vgic_v2/v3_enable
  KVM: arm/arm64: vgic-new: vgic_init: implement map_resources
  KVM: arm/arm64: vgic-new: vgic_init: implement vgic_init
  KVM: arm/arm64: vgic-new: vgic_init: implement vgic_create
  KVM: arm/arm64: vgic-new: vgic_init: implement kvm_vgic_hyp_init
  ...
2016-05-27 13:41:54 -07:00
Paolo Bonzini
44bcc92238 KVM/ARM Changes for v4.7 take 2
"The GIC is dead; Long live the GIC"
 
 This set of changes include the new vgic, which is a reimplementation of
 our horribly broken legacy vgic implementation.  The two implementations
 will live side-by-side (with the new being the configured default) for
 one kernel release and then we'll remove it.
 
 Also fixes a non-critical issue with virtual abort injection to guests.
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Merge tag 'kvm-arm-for-4-7-take2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-next

KVM/ARM Changes for v4.7 take 2

"The GIC is dead; Long live the GIC"

This set of changes include the new vgic, which is a reimplementation of
our horribly broken legacy vgic implementation.  The two implementations
will live side-by-side (with the new being the configured default) for
one kernel release and then we'll remove it.

Also fixes a non-critical issue with virtual abort injection to guests.
2016-05-24 12:10:51 +02:00
Christoffer Dall
35a2d58588 KVM: arm/arm64: vgic-new: Synchronize changes to active state
When modifying the active state of an interrupt via the MMIO interface,
we should ensure that the write has the intended effect.

If a guest sets an interrupt to active, but that interrupt is already
flushed into a list register on a running VCPU, then that VCPU will
write the active state back into the struct vgic_irq upon returning from
the guest and syncing its state.  This is a non-benign race, because the
guest can observe that an interrupt is not active, and it can have a
reasonable expectations that other VCPUs will not ack any IRQs, and then
set the state to active, and expect it to stay that way.  Currently we
are not honoring this case.

Thefore, change both the SACTIVE and CACTIVE mmio handlers to stop the
world, change the irq state, potentially queue the irq if we're setting
it to active, and then continue.

We take this chance to slightly optimize these functions by not stopping
the world when touching private interrupts where there is inherently no
possible race.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 16:26:38 +02:00
Christoffer Dall
b13216cf60 KVM: arm/arm64: Provide functionality to pause and resume a guest
For some rare corner cases in our VGIC emulation later we have to stop
the guest to make sure the VGIC state is consistent.
Provide the necessary framework to pause and resume a guest.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
2016-05-20 15:39:43 +02:00
Linus Torvalds
7beaa24ba4 Small release overall.
- x86: miscellaneous fixes, AVIC support (local APIC virtualization,
 AMD version)
 
 - s390: polling for interrupts after a VCPU goes to halted state is
 now enabled for s390; use hardware provided information about facility
 bits that do not need any hypervisor activity, and other fixes for
 cpu models and facilities; improve perf output; floating interrupt
 controller improvements.
 
 - MIPS: miscellaneous fixes
 
 - PPC: bugfixes only
 
 - ARM: 16K page size support, generic firmware probing layer for
 timer and GIC
 
 Christoffer Dall (KVM-ARM maintainer) says:
 "There are a few changes in this pull request touching things outside
  KVM, but they should all carry the necessary acks and it made the
  merge process much easier to do it this way."
 
 though actually the irqchip maintainers' acks didn't make it into the
 patches.  Marc Zyngier, who is both irqchip and KVM-ARM maintainer,
 later acked at http://mid.gmane.org/573351D1.4060303@arm.com
 "more formally and for documentation purposes".
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "Small release overall.

  x86:
   - miscellaneous fixes
   - AVIC support (local APIC virtualization, AMD version)

  s390:
   - polling for interrupts after a VCPU goes to halted state is now
     enabled for s390
   - use hardware provided information about facility bits that do not
     need any hypervisor activity, and other fixes for cpu models and
     facilities
   - improve perf output
   - floating interrupt controller improvements.

  MIPS:
   - miscellaneous fixes

  PPC:
   - bugfixes only

  ARM:
   - 16K page size support
   - generic firmware probing layer for timer and GIC

  Christoffer Dall (KVM-ARM maintainer) says:
    "There are a few changes in this pull request touching things
     outside KVM, but they should all carry the necessary acks and it
     made the merge process much easier to do it this way."

  though actually the irqchip maintainers' acks didn't make it into the
  patches.  Marc Zyngier, who is both irqchip and KVM-ARM maintainer,
  later acked at http://mid.gmane.org/573351D1.4060303@arm.com ('more
  formally and for documentation purposes')"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (82 commits)
  KVM: MTRR: remove MSR 0x2f8
  KVM: x86: make hwapic_isr_update and hwapic_irr_update look the same
  svm: Manage vcpu load/unload when enable AVIC
  svm: Do not intercept CR8 when enable AVIC
  svm: Do not expose x2APIC when enable AVIC
  KVM: x86: Introducing kvm_x86_ops.apicv_post_state_restore
  svm: Add VMEXIT handlers for AVIC
  svm: Add interrupt injection via AVIC
  KVM: x86: Detect and Initialize AVIC support
  svm: Introduce new AVIC VMCB registers
  KVM: split kvm_vcpu_wake_up from kvm_vcpu_kick
  KVM: x86: Introducing kvm_x86_ops VCPU blocking/unblocking hooks
  KVM: x86: Introducing kvm_x86_ops VM init/destroy hooks
  KVM: x86: Rename kvm_apic_get_reg to kvm_lapic_get_reg
  KVM: x86: Misc LAPIC changes to expose helper functions
  KVM: shrink halt polling even more for invalid wakeups
  KVM: s390: set halt polling to 80 microseconds
  KVM: halt_polling: provide a way to qualify wakeups during poll
  KVM: PPC: Book3S HV: Re-enable XICS fast path for irqfd-generated interrupts
  kvm: Conditionally register IRQ bypass consumer
  ...
2016-05-19 11:27:09 -07:00
Linus Torvalds
be092017b6 arm64 updates for 4.7:
- virt_to_page/page_address optimisations
 
 - Support for NUMA systems described using device-tree
 
 - Support for hibernate/suspend-to-disk
 
 - Proper support for maxcpus= command line parameter
 
 - Detection and graceful handling of AArch64-only CPUs
 
 - Miscellaneous cleanups and non-critical fixes
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:

 - virt_to_page/page_address optimisations

 - support for NUMA systems described using device-tree

 - support for hibernate/suspend-to-disk

 - proper support for maxcpus= command line parameter

 - detection and graceful handling of AArch64-only CPUs

 - miscellaneous cleanups and non-critical fixes

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits)
  arm64: do not enforce strict 16 byte alignment to stack pointer
  arm64: kernel: Fix incorrect brk randomization
  arm64: cpuinfo: Missing NULL terminator in compat_hwcap_str
  arm64: secondary_start_kernel: Remove unnecessary barrier
  arm64: Ensure pmd_present() returns false after pmd_mknotpresent()
  arm64: Replace hard-coded values in the pmd/pud_bad() macros
  arm64: Implement pmdp_set_access_flags() for hardware AF/DBM
  arm64: Fix typo in the pmdp_huge_get_and_clear() definition
  arm64: mm: remove unnecessary EXPORT_SYMBOL_GPL
  arm64: always use STRICT_MM_TYPECHECKS
  arm64: kvm: Fix kvm teardown for systems using the extended idmap
  arm64: kaslr: increase randomization granularity
  arm64: kconfig: drop CONFIG_RTC_LIB dependency
  arm64: make ARCH_SUPPORTS_DEBUG_PAGEALLOC depend on !HIBERNATION
  arm64: hibernate: Refuse to hibernate if the boot cpu is offline
  arm64: kernel: Add support for hibernate/suspend-to-disk
  PM / Hibernate: Call flush_icache_range() on pages restored in-place
  arm64: Add new asm macro copy_page
  arm64: Promote KERNEL_START/KERNEL_END definitions to a header file
  arm64: kernel: Include _AC definition in page.h
  ...
2016-05-16 17:17:24 -07:00
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