Commit Graph

106 Commits

Author SHA1 Message Date
Marc Zyngier 773299a570 KVM: arm/arm64: vgic: Prevent userspace injection of a mapped interrupt
Virtual interrupts mapped to a HW interrupt should only be triggered
from inside the kernel. Otherwise, you could end up confusing the
kernel (and the GIC's) state machine.

Rearrange the injection path so that kvm_vgic_inject_irq is
used for non-mapped interrupts, and kvm_vgic_inject_mapped_irq is
used for mapped interrupts. The latter should only be called from
inside the kernel (timer, irqfd).

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:26 +01:00
Marc Zyngier 6e84e0e067 KVM: arm/arm64: vgic: Add vgic_{get,set}_phys_irq_active
In order to control the active state of an interrupt, introduce
a pair of accessors allowing the state to be set/queried.

This only affects the logical state, and the HW state will only be
applied at world-switch time.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:26 +01:00
Marc Zyngier 08fd6461e8 KVM: arm/arm64: vgic: Allow HW interrupts to be queued to a guest
To allow a HW interrupt to be injected into a guest, we lookup the
guest virtual interrupt in the irq_phys_map list, and if we have
a match, encode both interrupts in the LR.

We also mark the interrupt as "active" at the host distributor level.

On guest EOI on the virtual interrupt, the host interrupt will be
deactivated.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:25 +01:00
Marc Zyngier 6c3d63c9a2 KVM: arm/arm64: vgic: Allow dynamic mapping of physical/virtual interrupts
In order to be able to feed physical interrupts to a guest, we need
to be able to establish the virtual-physical mapping between the two
worlds.

The mappings are kept in a set of RCU lists, indexed by virtual interrupts.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:25 +01:00
Marc Zyngier 7a67b4b7e0 KVM: arm/arm64: vgic: Relax vgic_can_sample_irq for edge IRQs
We only set the irq_queued flag for level interrupts, meaning
that "!vgic_irq_is_queued(vcpu, irq)" is a good enough predicate
for all interrupts.

This will allow us to inject edge HW interrupts, for which the
state ACTIVE+PENDING is not allowed.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:25 +01:00
Linus Torvalds e3d8238d7f arm64 updates for 4.2, mostly refactoring/clean-up:
- CPU ops and PSCI (Power State Coordination Interface) refactoring
   following the merging of the arm64 ACPI support, together with
   handling of Trusted (secure) OS instances
 
 - Using fixmap for permanent FDT mapping, removing the initial dtb
   placement requirements (within 512MB from the start of the kernel
   image). This required moving the FDT self reservation out of the
   memreserve processing
 
 - Idmap (1:1 mapping used for MMU on/off) handling clean-up
 
 - Removing flush_cache_all() - not safe on ARM unless the MMU is off.
   Last stages of CPU power down/up are handled by firmware already
 
 - "Alternatives" (run-time code patching) refactoring and support for
   immediate branch patching, GICv3 CPU interface access
 
 - User faults handling clean-up
 
 And some fixes:
 
 - Fix for VDSO building with broken ELF toolchains
 
 - Fixing another case of init_mm.pgd usage for user mappings (during
   ASID roll-over broadcasting)
 
 - Fix for FPSIMD reloading after CPU hotplug
 
 - Fix for missing syscall trace exit
 
 - Workaround for .inst asm bug
 
 - Compat fix for switching the user tls tpidr_el0 register
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:
 "Mostly refactoring/clean-up:

   - CPU ops and PSCI (Power State Coordination Interface) refactoring
     following the merging of the arm64 ACPI support, together with
     handling of Trusted (secure) OS instances

   - Using fixmap for permanent FDT mapping, removing the initial dtb
     placement requirements (within 512MB from the start of the kernel
     image).  This required moving the FDT self reservation out of the
     memreserve processing

   - Idmap (1:1 mapping used for MMU on/off) handling clean-up

   - Removing flush_cache_all() - not safe on ARM unless the MMU is off.
     Last stages of CPU power down/up are handled by firmware already

   - "Alternatives" (run-time code patching) refactoring and support for
     immediate branch patching, GICv3 CPU interface access

   - User faults handling clean-up

  And some fixes:

   - Fix for VDSO building with broken ELF toolchains

   - Fix another case of init_mm.pgd usage for user mappings (during
     ASID roll-over broadcasting)

   - Fix for FPSIMD reloading after CPU hotplug

   - Fix for missing syscall trace exit

   - Workaround for .inst asm bug

   - Compat fix for switching the user tls tpidr_el0 register"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (42 commits)
  arm64: use private ratelimit state along with show_unhandled_signals
  arm64: show unhandled SP/PC alignment faults
  arm64: vdso: work-around broken ELF toolchains in Makefile
  arm64: kernel: rename __cpu_suspend to keep it aligned with arm
  arm64: compat: print compat_sp instead of sp
  arm64: mm: Fix freeing of the wrong memmap entries with !SPARSEMEM_VMEMMAP
  arm64: entry: fix context tracking for el0_sp_pc
  arm64: defconfig: enable memtest
  arm64: mm: remove reference to tlb.S from comment block
  arm64: Do not attempt to use init_mm in reset_context()
  arm64: KVM: Switch vgic save/restore to alternative_insn
  arm64: alternative: Introduce feature for GICv3 CPU interface
  arm64: psci: fix !CONFIG_HOTPLUG_CPU build warning
  arm64: fix bug for reloading FPSIMD state after CPU hotplug.
  arm64: kernel thread don't need to save fpsimd context.
  arm64: fix missing syscall trace exit
  arm64: alternative: Work around .inst assembler bugs
  arm64: alternative: Merge alternative-asm.h into alternative.h
  arm64: alternative: Allow immediate branch as alternative instruction
  arm64: Rework alternate sequence for ARM erratum 845719
  ...
2015-06-24 10:02:15 -07:00
Marc Zyngier c62e631d4a KVM: arm/arm64: vgic: Remove useless arm-gic.h #include
Back in the days, vgic.c used to have an intimate knowledge of
the actual GICv2. These days, this has been abstracted away into
hardware-specific backends.

Remove the now useless arm-gic.h #include directive, making it
clear that GICv2 specific code doesn't belong here.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-06-18 15:50:31 +01:00
Marc Zyngier 4839ddc27b KVM: arm/arm64: vgic: Avoid injecting reserved IRQ numbers
Commit fd1d0ddf2a (KVM: arm/arm64: check IRQ number on userland
injection) rightly limited the range of interrupts userspace can
inject in a guest, but failed to consider the (unlikely) case where
a guest is configured with 1024 interrupts.

In this case, interrupts ranging from 1020 to 1023 are unuseable,
as they have a special meaning for the GIC CPU interface.

Make sure that these number cannot be used as an IRQ. Also delete
a redundant (and similarily buggy) check in kvm_set_irq.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: <stable@vger.kernel.org> # 4.1, 4.0, 3.19, 3.18
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-06-17 15:18:59 +01:00
Marc Zyngier 8a14849b4a arm64: KVM: Switch vgic save/restore to alternative_insn
So far, we configured the world-switch by having a small array
of pointers to the save and restore functions, depending on the
GIC used on the platform.

Loading these values each time is a bit silly (they never change),
and it makes sense to rely on the instruction patching instead.

This leads to a nice cleanup of the code.

Acked-by: Will Deacon <will.deacon@arm.com>
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>
2015-06-12 15:12:08 +01:00
Andre Przywara fd1d0ddf2a KVM: arm/arm64: check IRQ number on userland injection
When userland injects a SPI via the KVM_IRQ_LINE ioctl we currently
only check it against a fixed limit, which historically is set
to 127. With the new dynamic IRQ allocation the effective limit may
actually be smaller (64).
So when now a malicious or buggy userland injects a SPI in that
range, we spill over on our VGIC bitmaps and bytemaps memory.
I could trigger a host kernel NULL pointer dereference with current
mainline by injecting some bogus IRQ number from a hacked kvmtool:
-----------------
....
DEBUG: kvm_vgic_inject_irq(kvm, cpu=0, irq=114, level=1)
DEBUG: vgic_update_irq_pending(kvm, cpu=0, irq=114, level=1)
DEBUG: IRQ #114 still in the game, writing to bytemap now...
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = ffffffc07652e000
[00000000] *pgd=00000000f658b003, *pud=00000000f658b003, *pmd=0000000000000000
Internal error: Oops: 96000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 1053 Comm: lkvm-msi-irqinj Not tainted 4.0.0-rc7+ #3027
Hardware name: FVP Base (DT)
task: ffffffc0774e9680 ti: ffffffc0765a8000 task.ti: ffffffc0765a8000
PC is at kvm_vgic_inject_irq+0x234/0x310
LR is at kvm_vgic_inject_irq+0x30c/0x310
pc : [<ffffffc0000ae0a8>] lr : [<ffffffc0000ae180>] pstate: 80000145
.....

So this patch fixes this by checking the SPI number against the
actual limit. Also we remove the former legacy hard limit of
127 in the ioctl code.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
CC: <stable@vger.kernel.org> # 4.0, 3.19, 3.18
[maz: wrap KVM_ARM_IRQ_GIC_MAX with #ifndef __KERNEL__,
as suggested by Christopher Covington]
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-04-22 15:42:24 +01:00
Eric Auger 0b3289ebc2 KVM: arm: irqfd: fix value returned by kvm_irq_map_gsi
irqfd/arm curently does not support routing. kvm_irq_map_gsi is
supposed to return all the routing entries associated with the
provided gsi and return the number of those entries. We should
return 0 at this point.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-04-22 15:37:54 +01:00
Paolo Bonzini bf0fb67cf9 KVM/ARM changes for v4.1:
- fixes for live migration
 - irqfd support
 - kvm-io-bus & vgic rework to enable ioeventfd
 - page ageing for stage-2 translation
 - various cleanups
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Merge tag 'kvm-arm-for-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into 'kvm-next'

KVM/ARM changes for v4.1:

- fixes for live migration
- irqfd support
- kvm-io-bus & vgic rework to enable ioeventfd
- page ageing for stage-2 translation
- various cleanups
2015-04-07 18:09:20 +02:00
Andre Przywara 950324ab81 KVM: arm/arm64: rework MMIO abort handling to use KVM MMIO bus
Currently we have struct kvm_exit_mmio for encapsulating MMIO abort
data to be passed on from syndrome decoding all the way down to the
VGIC register handlers. Now as we switch the MMIO handling to be
routed through the KVM MMIO bus, it does not make sense anymore to
use that structure already from the beginning. So we keep the data in
local variables until we put them into the kvm_io_bus framework.
Then we fill kvm_exit_mmio in the VGIC only, making it a VGIC private
structure. On that way we replace the data buffer in that structure
with a pointer pointing to a single location in a local variable, so
we get rid of some copying on the way.
With all of the virtual GIC emulation code now being registered with
the kvm_io_bus, we can remove all of the old MMIO handling code and
its dispatching functionality.

I didn't bother to rename kvm_exit_mmio (to vgic_mmio or something),
because that touches a lot of code lines without any good reason.

This is based on an original patch by Nikolay.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Cc: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-03-30 17:07:19 +01:00
Andre Przywara 6777f77f0f KVM: arm/arm64: implement kvm_io_bus MMIO handling for the VGIC
Currently we use a lot of VGIC specific code to do the MMIO
dispatching.
Use the previous reworks to add kvm_io_bus style MMIO handlers.

Those are not yet called by the MMIO abort handler, also the actual
VGIC emulator function do not make use of it yet, but will be enabled
with the following patches.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-03-26 21:43:14 +00:00
Andre Przywara 9f199d0a0e KVM: arm/arm64: simplify vgic_find_range() and callers
The vgic_find_range() function in vgic.c takes a struct kvm_exit_mmio
argument, but actually only used the length field in there. Since we
need to get rid of that structure in that part of the code anyway,
let's rework the function (and it's callers) to pass the length
argument to the function directly.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-03-26 21:43:14 +00:00
Andre Przywara cf50a1eb43 KVM: arm/arm64: rename struct kvm_mmio_range to vgic_io_range
The name "kvm_mmio_range" is a bit bold, given that it only covers
the VGIC's MMIO ranges. To avoid confusion with kvm_io_range, rename
it to vgic_io_range.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-03-26 21:43:14 +00:00
Christoffer Dall 47a98b15ba arm/arm64: KVM: support for un-queuing active IRQs
Migrating active interrupts causes the active state to be lost
completely. This implements some additional bitmaps to track the active
state on the distributor and export this to user space.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-03-14 13:46:44 +01:00
Alex Bennée 71760950bf arm/arm64: KVM: add a common vgic_queue_irq_to_lr fn
This helps re-factor away some of the repetitive code and makes the code
flow more nicely.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-03-14 13:44:52 +01:00
Christoffer Dall ae705930fc arm/arm64: KVM: Keep elrsr/aisr in sync with software model
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 <marc.zyngier@arm.com>
Reported-by: Alex Bennee <alex.bennee@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-03-14 13:42:07 +01:00
Wei Yongjun b52104e509 arm/arm64: KVM: fix missing unlock on error in kvm_vgic_create()
Add the missing unlock before return from function kvm_vgic_create()
in the error handling case.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-03-13 11:40:57 +01:00
Eric Auger 174178fed3 KVM: arm/arm64: add irqfd support
This patch enables irqfd on arm/arm64.

Both irqfd and resamplefd are supported. Injection is implemented
in vgic.c without routing.

This patch enables CONFIG_HAVE_KVM_EVENTFD and CONFIG_HAVE_KVM_IRQFD.

KVM_CAP_IRQFD is now advertised. KVM_CAP_IRQFD_RESAMPLE capability
automatically is advertised as soon as CONFIG_HAVE_KVM_IRQFD is set.

Irqfd injection is restricted to SPI. The rationale behind not
supporting PPI irqfd injection is that any device using a PPI would
be a private-to-the-CPU device (timer for instance), so its state
would have to be context-switched along with the VCPU and would
require in-kernel wiring anyhow. It is not a relevant use case for
irqfds.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-03-12 15:15:34 +01:00
Eric Auger 649cf73994 KVM: arm/arm64: remove coarse grain dist locking at kvm_vgic_sync_hwstate
To prepare for irqfd addition, coarse grain locking is removed at
kvm_vgic_sync_hwstate level and finer grain locking is introduced in
vgic_process_maintenance only.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-03-12 15:15:33 +01:00
Mark Rutland 0f37247574 KVM: vgic: add virt-capable compatible strings
Several dts only list "arm,cortex-a7-gic" or "arm,gic-400" in their GIC
compatible list, and while this is correct (and supported by the GIC
driver), KVM will fail to detect that it can support these cases.

This patch adds the missing strings to the VGIC code. The of_device_id
entries are padded to keep the probe function data aligned.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Michal Simek <monstr@monstr.eu>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-03-11 15:27:48 +01:00
Andre Przywara 4fa96afd94 arm/arm64: KVM: force alignment of VGIC dist/CPU/redist addresses
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 <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:33 +01:00
Andre Przywara ac3d373564 arm/arm64: KVM: allow userland to request a virtual GICv3
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 <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:33 +01:00
Andre Przywara b5d84ff600 arm/arm64: KVM: enable kernel side of GICv3 emulation
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 <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:32 +01:00
Andre Przywara a0675c25d6 arm/arm64: KVM: add virtual GICv3 distributor emulation
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 <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:31 +01:00
Andre Przywara 9fedf14677 arm/arm64: KVM: add opaque private pointer to MMIO data
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 <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:30 +01:00
Andre Przywara 1d916229e3 arm/arm64: KVM: split GICv2 specific emulation code from vgic.c
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 <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>

-------
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 <christoffer.dall@linaro.org>
2015-01-20 18:25:30 +01:00
Andre Przywara 832158125d arm/arm64: KVM: add vgic.h header file
vgic.c is currently a mixture of generic vGIC emulation code and
functions specific to emulating a GICv2. To ease the addition of
GICv3 later, we create new header file vgic.h, which holds constants
and prototypes of commonly used functions.
Rename some identifiers to avoid name space clutter.
I removed the long-standing comment about using the kvm_io_bus API
to tackle the GIC register ranges, as it wouldn't be a win for us
anymore.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>

-------
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:
* moved definitions and prototypes from vgic.c to vgic.h:
  - VGIC_ADDR_UNDEF
  - ACCESS_{READ,WRITE}_*
  - vgic_init()
  - vgic_update_state()
  - vgic_kick_vcpus()
  - vgic_get_vmcr()
  - vgic_set_vmcr()
  - struct mmio_range {} (renamed to struct kvm_mmio_range)
* removed static keyword and exported prototype in vgic.h:
  - vgic_bitmap_get_reg()
  - vgic_bitmap_set_irq_val()
  - vgic_bitmap_get_shared_map()
  - vgic_bytemap_get_reg()
  - vgic_dist_irq_set_pending()
  - vgic_dist_irq_clear_pending()
  - vgic_cpu_irq_clear()
  - vgic_reg_access()
  - handle_mmio_raz_wi()
  - vgic_handle_enable_reg()
  - vgic_handle_set_pending_reg()
  - vgic_handle_clear_pending_reg()
  - vgic_handle_cfg_reg()
  - vgic_unqueue_irqs()
  - find_matching_range() (renamed to vgic_find_range)
  - vgic_handle_mmio_range()
  - vgic_update_state()
  - vgic_get_vmcr()
  - vgic_set_vmcr()
  - vgic_queue_irq()
  - vgic_kick_vcpus()
  - vgic_init()
  - vgic_v2_init_emulation()
  - vgic_has_attr_regs()
  - vgic_set_common_attr()
  - vgic_get_common_attr()
  - vgic_destroy()
  - vgic_create()
* moved functions to vgic.h (static inline):
  - mmio_data_read()
  - mmio_data_write()
  - is_in_range()

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:30 +01:00
Andre Przywara b60da146c1 arm/arm64: KVM: refactor/wrap vgic_set/get_attr()
vgic_set_attr() and vgic_get_attr() contain both code specific for
the emulated GIC as well as code for the userland facing, generic
part of the GIC.
Split the guest GIC facing code of from the generic part to allow
easier splitting later.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:29 +01:00
Andre Przywara d97f683d0f arm/arm64: KVM: refactor MMIO accessors
The MMIO accessors for GICD_I[CS]ENABLER, GICD_I[CS]PENDR and
GICD_ICFGR behave very similar for GICv2 and GICv3, although the way
the affected VCPU is determined differs.
Since we need them to access the registers from three different
places in the future, we factor out a generic, backend-facing
implementation and use small wrappers in the current GICv2 emulation.
This will ease adding GICv3 accessors later.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:29 +01:00
Andre Przywara 3caa2d8c3b arm/arm64: KVM: make the maximum number of vCPUs a per-VM value
Currently the maximum number of vCPUs supported is a global value
limited by the used GIC model. GICv3 will lift this limit, but we
still need to observe it for guests using GICv2.
So the maximum number of vCPUs is per-VM value, depending on the
GIC model the guest uses.
Store and check the value in struct kvm_arch, but keep it down to
8 for now.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:28 +01:00
Andre Przywara 4ce7ebdfc6 arm/arm64: KVM: dont rely on a valid GICH base address
To check whether the vGIC was already initialized, we currently check
the GICH base address for not being NULL. Since with GICv3 we may
get along without this address, lets use the irqchip_in_kernel()
function to detect an already initialized vGIC.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:27 +01:00
Andre Przywara ea2f83a7de arm/arm64: KVM: move kvm_register_device_ops() into vGIC probing
Currently we unconditionally register the GICv2 emulation device
during the host's KVM initialization. Since with GICv3 support we
may end up with only v2 or only v3 or both supported, we move the
registration into the GIC probing function, where we will later know
which combination is valid.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:27 +01:00
Andre Przywara b26e5fdac4 arm/arm64: KVM: introduce per-VM ops
Currently we only have one virtual GIC model supported, so all guests
use the same emulation code. With the addition of another model we
end up with different guests using potentially different vGIC models,
so we have to split up some functions to be per VM.
Introduce a vgic_vm_ops struct to hold function pointers for those
functions that are different and provide the necessary code to
initialize them.
Also split up the vgic_init() function to separate out VGIC model
specific functionality into a separate function, which will later be
different for a GICv3 model.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:26 +01:00
Andre Przywara 05bc8aafe6 arm/arm64: KVM: wrap 64 bit MMIO accesses with two 32 bit ones
Some GICv3 registers can and will be accessed as 64 bit registers.
Currently the register handling code can only deal with 32 bit
accesses, so we do two consecutive calls to cover this.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:26 +01:00
Andre Przywara 96415257a1 arm/arm64: KVM: refactor vgic_handle_mmio() function
Currently we only need to deal with one MMIO region for the GIC
emulation (the GICv2 distributor), but we soon need to extend this.
Refactor the existing code to allow easier addition of different
ranges without code duplication.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:25 +01:00
Andre Przywara 59892136c4 arm/arm64: KVM: pass down user space provided GIC type into vGIC code
With the introduction of a second emulated GIC model we need to let
userspace specify the GIC model to use for each VM. Pass the
userspace provided value down into the vGIC code and store it there
to differentiate later.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:25 +01:00
Eric Auger 065c003482 KVM: arm/arm64: vgic: add init entry to VGIC KVM device
Since the advent of VGIC dynamic initialization, this latter is
initialized quite late on the first vcpu run or "on-demand", when
injecting an IRQ or when the guest sets its registers.

This initialization could be initiated explicitly much earlier
by the users-space, as soon as it has provided the requested
dimensioning parameters.

This patch adds a new entry to the VGIC KVM device that allows
the user to manually request the VGIC init:
- a new KVM_DEV_ARM_VGIC_GRP_CTRL group is introduced.
- Its first attribute is KVM_DEV_ARM_VGIC_CTRL_INIT

The rationale behind introducing a group is to be able to add other
controls later on, if needed.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-11 14:12:15 +01:00
Eric Auger 66b030e48a KVM: arm/arm64: vgic: vgic_init returns -ENODEV when no online vcpu
To be more explicit on vgic initialization failure, -ENODEV is
returned by vgic_init when no online vcpus can be found at init.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-11 14:12:15 +01:00
Linus Torvalds 66dcff86ba 3.19 changes for KVM:
- spring cleaning: removed support for IA64, and for hardware-assisted
 virtualization on the PPC970
 - ARM, PPC, s390 all had only small fixes
 
 For x86:
 - small performance improvements (though only on weird guests)
 - usual round of hardware-compliancy fixes from Nadav
 - APICv fixes
 - XSAVES support for hosts and guests.  XSAVES hosts were broken because
 the (non-KVM) XSAVES patches inadvertently changed the KVM userspace
 ABI whenever XSAVES was enabled; hence, this part is going to stable.
 Guest support is just a matter of exposing the feature and CPUID leaves
 support.
 
 Right now KVM is broken for PPC BookE in your tree (doesn't compile).
 I'll reply to the pull request with a patch, please apply it either
 before the pull request or in the merge commit, in order to preserve
 bisectability somewhat.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM update from Paolo Bonzini:
 "3.19 changes for KVM:

   - spring cleaning: removed support for IA64, and for hardware-
     assisted virtualization on the PPC970

   - ARM, PPC, s390 all had only small fixes

  For x86:
   - small performance improvements (though only on weird guests)
   - usual round of hardware-compliancy fixes from Nadav
   - APICv fixes
   - XSAVES support for hosts and guests.  XSAVES hosts were broken
     because the (non-KVM) XSAVES patches inadvertently changed the KVM
     userspace ABI whenever XSAVES was enabled; hence, this part is
     going to stable.  Guest support is just a matter of exposing the
     feature and CPUID leaves support"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (179 commits)
  KVM: move APIC types to arch/x86/
  KVM: PPC: Book3S: Enable in-kernel XICS emulation by default
  KVM: PPC: Book3S HV: Improve H_CONFER implementation
  KVM: PPC: Book3S HV: Fix endianness of instruction obtained from HEIR register
  KVM: PPC: Book3S HV: Remove code for PPC970 processors
  KVM: PPC: Book3S HV: Tracepoints for KVM HV guest interactions
  KVM: PPC: Book3S HV: Simplify locking around stolen time calculations
  arch: powerpc: kvm: book3s_paired_singles.c: Remove unused function
  arch: powerpc: kvm: book3s_pr.c: Remove unused function
  arch: powerpc: kvm: book3s.c: Remove some unused functions
  arch: powerpc: kvm: book3s_32_mmu.c: Remove unused function
  KVM: PPC: Book3S HV: Check wait conditions before sleeping in kvmppc_vcore_blocked
  KVM: PPC: Book3S HV: ptes are big endian
  KVM: PPC: Book3S HV: Fix inaccuracies in ICP emulation for H_IPI
  KVM: PPC: Book3S HV: Fix KSM memory corruption
  KVM: PPC: Book3S HV: Fix an issue where guest is paused on receiving HMI
  KVM: PPC: Book3S HV: Fix computation of tlbie operand
  KVM: PPC: Book3S HV: Add missing HPTE unlock
  KVM: PPC: BookE: Improve irq inject tracepoint
  arm/arm64: KVM: Require in-kernel vgic for the arch timers
  ...
2014-12-18 16:05:28 -08:00
Christoffer Dall ca7d9c829d arm/arm64: KVM: Initialize the vgic on-demand when injecting IRQs
Userspace assumes that it can wire up IRQ injections after having
created all VCPUs and after having created the VGIC, but potentially
before starting the first VCPU.  This can currently lead to lost IRQs
because the state of that IRQ injection is not stored anywhere and we
don't return an error to userspace.

We haven't seen this problem manifest itself yet, presumably because
guests reset the devices on boot, but this could cause issues with
migration and other non-standard startup configurations.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-15 11:36:21 +01:00
Christoffer Dall 1f57be2895 arm/arm64: KVM: Add (new) vgic_initialized macro
Some code paths will need to check to see if the internal state of the
vgic has been initialized (such as when creating new VCPUs), so
introduce such a macro that checks the nr_cpus field which is set when
the vgic has been initialized.

Also set nr_cpus = 0 in kvm_vgic_destroy, because the error path in
vgic_init() will call this function, and code should never errornously
assume the vgic to be properly initialized after an error.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-13 14:17:10 +01:00
Christoffer Dall c52edf5f8c arm/arm64: KVM: Rename vgic_initialized to vgic_ready
The vgic_initialized() macro currently returns the state of the
vgic->ready flag, which indicates if the vgic is ready to be used when
running a VM, not specifically if its internal state has been
initialized.

Rename the macro accordingly in preparation for a more nuanced
initialization flow.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-13 14:17:05 +01:00
Peter Maydell 6d3cfbe21b arm/arm64: KVM: vgic: move reset initialization into vgic_init_maps()
VGIC initialization currently happens in three phases:
 (1) kvm_vgic_create() (triggered by userspace GIC creation)
 (2) vgic_init_maps() (triggered by userspace GIC register read/write
     requests, or from kvm_vgic_init() if not already run)
 (3) kvm_vgic_init() (triggered by first VM run)

We were doing initialization of some state to correspond with the
state of a freshly-reset GIC in kvm_vgic_init(); this is too late,
since it will overwrite changes made by userspace using the
register access APIs before the VM is run. Move this initialization
earlier, into the vgic_init_maps() phase.

This fixes a bug where QEMU could successfully restore a saved
VM state snapshot into a VM that had already been run, but could
not restore it "from cold" using the -loadvm command line option
(the symptoms being that the restored VM would run but interrupts
were ignored).

Finally rename vgic_init_maps to vgic_init and renamed kvm_vgic_init to
kvm_vgic_map_resources.

  [ This patch is originally written by Peter Maydell, but I have
    modified it somewhat heavily, renaming various bits and moving code
    around.  If something is broken, I am to be blamed. - Christoffer ]

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-13 14:15:52 +01:00
Christoffer Dall 6b50f54064 arm/arm64: KVM: vgic: Fix error code in kvm_vgic_create()
If we detect another vCPU is running we just exit and return 0 as if we
succesfully created the VGIC, but the VGIC wouldn't actual be created.

This shouldn't break in-kernel behavior because the kernel will not
observe the failed the attempt to create the VGIC, but userspace could
be rightfully confused.

Cc: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-11-26 14:40:44 +01:00
Shannon Zhao 016ed39c54 arm/arm64: KVM: vgic: kick the specific vcpu instead of iterating through all
When call kvm_vgic_inject_irq to inject interrupt, we can known which
vcpu the interrupt for by the irq_num and the cpuid. So we should just
kick this vcpu to avoid iterating through all.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Shannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-11-26 10:19:37 +00:00
Christoffer Dall b1e952b4e4 arm/arm64: vgic: Remove unreachable irq_clear_pending
When 'injecting' an edge-triggered interrupt with a falling edge we
shouldn't clear the pending state on the distributor.  In fact, we
don't, because the check in vgic_validate_injection would prevent us
from ever reaching this bit of code.

Remove the unreachable snippet.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-11-25 13:57:28 +00:00
wanghaibin 7d39f9e32c KVM: ARM: VGIC: Optimize the vGIC vgic_update_irq_pending function.
When vgic_update_irq_pending with level-sensitive false, it is need to
deactivates an interrupt, and, it can go to out directly.
Here return a false value, because it will be not need to kick.

Signed-off-by: wanghaibin <wanghaibin.wang@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-11-25 13:57:26 +00:00