linux-toradex.git/virt/kvm/arm, branch v4.0

arm/arm64: KVM: Keep elrsr/aisr in sync with software model

2015-03-14T12:42:07+00:00

There is an interesting bug in the vgic code, which manifests itself
when the KVM run loop has a signal pending or needs a vmid generation
rollover after having disabled interrupts but before actually switching
to the guest.

In this case, we flush the vgic as usual, but we sync back the vgic
state and exit to userspace before entering the guest.  The consequence
is that we will be syncing the list registers back to the software model
using the GICH_ELRSR and GICH_EISR from the last execution of the guest,
potentially overwriting a list register containing an interrupt.

This showed up during migration testing where we would capture a state
where the VM has masked the arch timer but there were no interrupts,
resulting in a hung test.

Cc: Marc Zyngier 
Reported-by: Alex Bennee 
Signed-off-by: Christoffer Dall 
Signed-off-by: Alex Bennée 
Acked-by: Marc Zyngier 
Signed-off-by: Christoffer Dall

arm/arm64: KVM: fix missing unlock on error in kvm_vgic_create()

2015-03-13T10:40:57+00:00

Add the missing unlock before return from function kvm_vgic_create()
in the error handling case.

Signed-off-by: Wei Yongjun 
Signed-off-by: Christoffer Dall

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

2015-02-13T17:55:09+00:00

Pull KVM update from Paolo Bonzini:
 "Fairly small update, but there are some interesting new features.

  Common:
     Optional support for adding a small amount of polling on each HLT
     instruction executed in the guest (or equivalent for other
     architectures).  This can improve latency up to 50% on some
     scenarios (e.g. O_DSYNC writes or TCP_RR netperf tests).  This
     also has to be enabled manually for now, but the plan is to
     auto-tune this in the future.

  ARM/ARM64:
     The highlights are support for GICv3 emulation and dirty page
     tracking

  s390:
     Several optimizations and bugfixes.  Also a first: a feature
     exposed by KVM (UUID and long guest name in /proc/sysinfo) before
     it is available in IBM's hypervisor! :)

  MIPS:
     Bugfixes.

  x86:
     Support for PML (page modification logging, a new feature in
     Broadwell Xeons that speeds up dirty page tracking), nested
     virtualization improvements (nested APICv---a nice optimization),
     usual round of emulation fixes.

     There is also a new option to reduce latency of the TSC deadline
     timer in the guest; this needs to be tuned manually.

     Some commits are common between this pull and Catalin's; I see you
     have already included his tree.

  Powerpc:
     Nothing yet.

     The KVM/PPC changes will come in through the PPC maintainers,
     because I haven't received them yet and I might end up being
     offline for some part of next week"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (130 commits)
  KVM: ia64: drop kvm.h from installed user headers
  KVM: x86: fix build with !CONFIG_SMP
  KVM: x86: emulate: correct page fault error code for NoWrite instructions
  KVM: Disable compat ioctl for s390
  KVM: s390: add cpu model support
  KVM: s390: use facilities and cpu_id per KVM
  KVM: s390/CPACF: Choose crypto control block format
  s390/kernel: Update /proc/sysinfo file with Extended Name and UUID
  KVM: s390: reenable LPP facility
  KVM: s390: floating irqs: fix user triggerable endless loop
  kvm: add halt_poll_ns module parameter
  kvm: remove KVM_MMIO_SIZE
  KVM: MIPS: Don't leak FPU/DSP to guest
  KVM: MIPS: Disable HTW while in guest
  KVM: nVMX: Enable nested posted interrupt processing
  KVM: nVMX: Enable nested virtual interrupt delivery
  KVM: nVMX: Enable nested apic register virtualization
  KVM: nVMX: Make nested control MSRs per-cpu
  KVM: nVMX: Enable nested virtualize x2apic mode
  KVM: nVMX: Prepare for using hardware MSR bitmap
  ...

arm/arm64: KVM: force alignment of VGIC dist/CPU/redist addresses

2015-01-20T17:25:33+00:00

Although the GIC architecture requires us to map the MMIO regions
only at page aligned addresses, we currently do not enforce this from
the kernel side.
Restrict any vGICv2 regions to be 4K aligned and any GICv3 regions
to be 64K aligned. Document this requirement.

Signed-off-by: Andre Przywara 
Signed-off-by: Christoffer Dall

arm/arm64: KVM: allow userland to request a virtual GICv3

2015-01-20T17:25:33+00:00

With all of the GICv3 code in place now we allow userland to ask the
kernel for using a virtual GICv3 in the guest.
Also we provide the necessary support for guests setting the memory
addresses for the virtual distributor and redistributors.
This requires some userland code to make use of that feature and
explicitly ask for a virtual GICv3.
Document that KVM_CREATE_IRQCHIP only works for GICv2, but is
considered legacy and using KVM_CREATE_DEVICE is preferred.

Signed-off-by: Andre Przywara 
Signed-off-by: Christoffer Dall

arm/arm64: KVM: enable kernel side of GICv3 emulation

2015-01-20T17:25:32+00:00

With all the necessary GICv3 emulation code in place, we can now
connect the code to the GICv3 backend in the kernel.
The LR register handling is different depending on the emulated GIC
model, so provide different implementations for each.
Also allow non-v2-compatible GICv3 implementations (which don't
provide MMIO regions for the virtual CPU interface in the DT), but
restrict those hosts to support GICv3 guests only.
If the device tree provides a GICv2 compatible GICV resource entry,
but that one is faulty, just disable the GICv2 emulation and let the
user use at least the GICv3 emulation for guests.
To provide proper support for the legacy KVM_CREATE_IRQCHIP ioctl,
note virtual GICv2 compatibility in struct vgic_params and use it
on creating a VGICv2.

Signed-off-by: Andre Przywara 
Signed-off-by: Christoffer Dall

arm64: KVM: add SGI generation register emulation

2015-01-20T17:25:32+00:00

While the generation of a (virtual) inter-processor interrupt (SGI)
on a GICv2 works by writing to a MMIO register, GICv3 uses the system
register ICC_SGI1R_EL1 to trigger them.
Add a trap handler function that calls the new SGI register handler
in the GICv3 code. As ICC_SRE_EL1.SRE at this point is still always 0,
this will not trap yet, but will only be used later when all the data
structures have been initialized properly.

Signed-off-by: Andre Przywara 
Reviewed-by: Christoffer Dall 
Signed-off-by: Christoffer Dall

arm/arm64: KVM: add virtual GICv3 distributor emulation

2015-01-20T17:25:31+00:00

With everything separated and prepared, we implement a model of a
GICv3 distributor and redistributors by using the existing framework
to provide handler functions for each register group.

Currently we limit the emulation to a model enforcing a single
security state, with SRE==1 (forcing system register access) and
ARE==1 (allowing more than 8 VCPUs).

We share some of the functions provided for GICv2 emulation, but take
the different ways of addressing (v)CPUs into account.
Save and restore is currently not implemented.

Similar to the split-off of the GICv2 specific code, the new emulation
code goes into a new file (vgic-v3-emul.c).

Signed-off-by: Andre Przywara 
Signed-off-by: Christoffer Dall

arm/arm64: KVM: add opaque private pointer to MMIO data

2015-01-20T17:25:30+00:00

For a GICv2 there is always only one (v)CPU involved: the one that
does the access. On a GICv3 the access to a CPU redistributor is
memory-mapped, but not banked, so the (v)CPU affected is determined by
looking at the MMIO address region being accessed.
To allow passing the affected CPU into the accessors later, extend
struct kvm_exit_mmio to add an opaque private pointer parameter.
The current GICv2 emulation just does not use it.

Signed-off-by: Andre Przywara 
Acked-by: Christoffer Dall 
Signed-off-by: Christoffer Dall

arm/arm64: KVM: split GICv2 specific emulation code from vgic.c

2015-01-20T17:25:30+00:00

vgic.c is currently a mixture of generic vGIC emulation code and
functions specific to emulating a GICv2. To ease the addition of
GICv3, split off strictly v2 specific parts into a new file
vgic-v2-emul.c.

Signed-off-by: Andre Przywara 
Acked-by: Christoffer Dall 

-------
As the diff isn't always obvious here (and to aid eventual rebases),
here is a list of high-level changes done to the code:
* added new file to respective arm/arm64 Makefiles
* moved GICv2 specific functions to vgic-v2-emul.c:
  - handle_mmio_misc()
  - handle_mmio_set_enable_reg()
  - handle_mmio_clear_enable_reg()
  - handle_mmio_set_pending_reg()
  - handle_mmio_clear_pending_reg()
  - handle_mmio_priority_reg()
  - vgic_get_target_reg()
  - vgic_set_target_reg()
  - handle_mmio_target_reg()
  - handle_mmio_cfg_reg()
  - handle_mmio_sgi_reg()
  - vgic_v2_unqueue_sgi()
  - read_set_clear_sgi_pend_reg()
  - write_set_clear_sgi_pend_reg()
  - handle_mmio_sgi_set()
  - handle_mmio_sgi_clear()
  - vgic_v2_handle_mmio()
  - vgic_get_sgi_sources()
  - vgic_dispatch_sgi()
  - vgic_v2_queue_sgi()
  - vgic_v2_map_resources()
  - vgic_v2_init()
  - vgic_v2_add_sgi_source()
  - vgic_v2_init_model()
  - vgic_v2_init_emulation()
  - handle_cpu_mmio_misc()
  - handle_mmio_abpr()
  - handle_cpu_mmio_ident()
  - vgic_attr_regs_access()
  - vgic_create() (renamed to vgic_v2_create())
  - vgic_destroy() (renamed to vgic_v2_destroy())
  - vgic_has_attr() (renamed to vgic_v2_has_attr())
  - vgic_set_attr() (renamed to vgic_v2_set_attr())
  - vgic_get_attr() (renamed to vgic_v2_get_attr())
  - struct kvm_mmio_range vgic_dist_ranges[]
  - struct kvm_mmio_range vgic_cpu_ranges[]
  - struct kvm_device_ops kvm_arm_vgic_v2_ops {}

Signed-off-by: Christoffer Dall