Commit Graph

92 Commits

Author SHA1 Message Date
Vladimir Murzin
ab510027dc arm64: KVM: Enable Common Not Private translations
We rely on cpufeature framework to detect and enable CNP so for KVM we
need to patch hyp to set CNP bit just before TTBR0_EL2 gets written.

For the guest we encode CNP bit while building vttbr, so we don't need
to bother with that in a world switch.

Reviewed-by: James Morse <james.morse@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-18 12:03:34 +01:00
Marc Zyngier
0db9dd8a0f KVM: arm/arm64: Stop using the kernel's {pmd,pud,pgd}_populate helpers
The {pmd,pud,pgd}_populate accessors usage have always been a bit weird
in KVM. We don't have a struct mm to pass (and neither does the kernel
most of the time, but still...), and the 32bit code has all kind of
cache maintenance that doesn't make sense on ARMv7+ when MP extensions
are mandatory (which is the case when the VEs are present).

Let's bite the bullet and provide our own implementations. The only bit
of architectural code left has to do with building the table entry
itself (arm64 having up to 52bit PA, arm lacking PUD level).

Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-07-09 11:37:42 +01:00
Marc Zyngier
88dc25e8ea KVM: arm/arm64: Consolidate page-table accessors
The arm and arm64 KVM page tables accessors are pointlessly different
between the two architectures, and likely both wrong one way or another:
arm64 lacks a dsb(), and arm doesn't use WRITE_ONCE.

Let's unify them.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-07-09 11:37:42 +01:00
Marc Zyngier
e48d53a91f arm64: KVM: Add support for Stage-2 control of memory types and cacheability
Up to ARMv8.3, the combinaison of Stage-1 and Stage-2 attributes
results in the strongest attribute of the two stages.  This means
that the hypervisor has to perform quite a lot of cache maintenance
just in case the guest has some non-cacheable mappings around.

ARMv8.4 solves this problem by offering a different mode (FWB) where
Stage-2 has total control over the memory attribute (this is limited
to systems where both I/O and instruction fetches are coherent with
the dcache). This is achieved by having a different set of memory
attributes in the page tables, and a new bit set in HCR_EL2.

On such a system, we can then safely sidestep any form of dcache
management.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-07-09 11:37:41 +01:00
Linus Torvalds
410feb75de arm64 updates for 4.18:
- Spectre v4 mitigation (Speculative Store Bypass Disable) support for
   arm64 using SMC firmware call to set a hardware chicken bit
 
 - ACPI PPTT (Processor Properties Topology Table) parsing support and
   enable the feature for arm64
 
 - Report signal frame size to user via auxv (AT_MINSIGSTKSZ). The
   primary motivation is Scalable Vector Extensions which requires more
   space on the signal frame than the currently defined MINSIGSTKSZ
 
 - ARM perf patches: allow building arm-cci as module, demote dev_warn()
   to dev_dbg() in arm-ccn event_init(), miscellaneous cleanups
 
 - cmpwait() WFE optimisation to avoid some spurious wakeups
 
 - L1_CACHE_BYTES reverted back to 64 (for performance reasons that have
   to do with some network allocations) while keeping ARCH_DMA_MINALIGN
   to 128. cache_line_size() returns the actual hardware Cache Writeback
   Granule
 
 - Turn LSE atomics on by default in Kconfig
 
 - Kernel fault reporting tidying
 
 - Some #include and miscellaneous cleanups
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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:
 "Apart from the core arm64 and perf changes, the Spectre v4 mitigation
  touches the arm KVM code and the ACPI PPTT support touches drivers/
  (acpi and cacheinfo). I should have the maintainers' acks in place.

  Summary:

   - Spectre v4 mitigation (Speculative Store Bypass Disable) support
     for arm64 using SMC firmware call to set a hardware chicken bit

   - ACPI PPTT (Processor Properties Topology Table) parsing support and
     enable the feature for arm64

   - Report signal frame size to user via auxv (AT_MINSIGSTKSZ). The
     primary motivation is Scalable Vector Extensions which requires
     more space on the signal frame than the currently defined
     MINSIGSTKSZ

   - ARM perf patches: allow building arm-cci as module, demote
     dev_warn() to dev_dbg() in arm-ccn event_init(), miscellaneous
     cleanups

   - cmpwait() WFE optimisation to avoid some spurious wakeups

   - L1_CACHE_BYTES reverted back to 64 (for performance reasons that
     have to do with some network allocations) while keeping
     ARCH_DMA_MINALIGN to 128. cache_line_size() returns the actual
     hardware Cache Writeback Granule

   - Turn LSE atomics on by default in Kconfig

   - Kernel fault reporting tidying

   - Some #include and miscellaneous cleanups"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (53 commits)
  arm64: Fix syscall restarting around signal suppressed by tracer
  arm64: topology: Avoid checking numa mask for scheduler MC selection
  ACPI / PPTT: fix build when CONFIG_ACPI_PPTT is not enabled
  arm64: cpu_errata: include required headers
  arm64: KVM: Move VCPU_WORKAROUND_2_FLAG macros to the top of the file
  arm64: signal: Report signal frame size to userspace via auxv
  arm64/sve: Thin out initialisation sanity-checks for sve_max_vl
  arm64: KVM: Add ARCH_WORKAROUND_2 discovery through ARCH_FEATURES_FUNC_ID
  arm64: KVM: Handle guest's ARCH_WORKAROUND_2 requests
  arm64: KVM: Add ARCH_WORKAROUND_2 support for guests
  arm64: KVM: Add HYP per-cpu accessors
  arm64: ssbd: Add prctl interface for per-thread mitigation
  arm64: ssbd: Introduce thread flag to control userspace mitigation
  arm64: ssbd: Restore mitigation status on CPU resume
  arm64: ssbd: Skip apply_ssbd if not using dynamic mitigation
  arm64: ssbd: Add global mitigation state accessor
  arm64: Add 'ssbd' command-line option
  arm64: Add ARCH_WORKAROUND_2 probing
  arm64: Add per-cpu infrastructure to call ARCH_WORKAROUND_2
  arm64: Call ARCH_WORKAROUND_2 on transitions between EL0 and EL1
  ...
2018-06-08 11:10:58 -07:00
Marc Zyngier
55e3748e89 arm64: KVM: Add ARCH_WORKAROUND_2 support for guests
In order to offer ARCH_WORKAROUND_2 support to guests, we need
a bit of infrastructure.

Let's add a flag indicating whether or not the guest uses
SSBD mitigation. Depending on the state of this flag, allow
KVM to disable ARCH_WORKAROUND_2 before entering the guest,
and enable it when exiting it.

Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-31 18:00:55 +01:00
Vincenzo Frascino
92faa7bea3 arm64: Remove duplicate include
"make includecheck" detected few duplicated includes in arch/arm64.

This patch removes the double inclusions.

Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-15 18:18:00 +01:00
Andre Przywara
bf308242ab KVM: arm/arm64: VGIC/ITS: protect kvm_read_guest() calls with SRCU lock
kvm_read_guest() will eventually look up in kvm_memslots(), which requires
either to hold the kvm->slots_lock or to be inside a kvm->srcu critical
section.
In contrast to x86 and s390 we don't take the SRCU lock on every guest
exit, so we have to do it individually for each kvm_read_guest() call.

Provide a wrapper which does that and use that everywhere.

Note that ending the SRCU critical section before returning from the
kvm_read_guest() wrapper is safe, because the data has been *copied*, so
we don't need to rely on valid references to the memslot anymore.

Cc: Stable <stable@vger.kernel.org> # 4.8+
Reported-by: Jan Glauber <jan.glauber@caviumnetworks.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-15 13:36:49 +02:00
Marc Zyngier
dee39247dc arm64: KVM: Allow mapping of vectors outside of the RAM region
We're now ready to map our vectors in weird and wonderful locations.
On enabling ARM64_HARDEN_EL2_VECTORS, a vector slot gets allocated
if this hasn't been already done via ARM64_HARDEN_BRANCH_PREDICTOR
and gets mapped outside of the normal RAM region, next to the
idmap.

That way, being able to obtain VBAR_EL2 doesn't reveal the mapping
of the rest of the hypervisor code.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 13:06:46 +00:00
Marc Zyngier
dc2e4633ff arm/arm64: KVM: Introduce EL2-specific executable mappings
Until now, all EL2 executable mappings were derived from their
EL1 VA. Since we want to decouple the vectors mapping from
the rest of the hypervisor, we need to be able to map some
text somewhere else.

The "idmap" region (for lack of a better name) is ideally suited
for this, as we have a huge range that hardly has anything in it.

Let's extend the IO allocator to also deal with executable mappings,
thus providing the required feature.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 13:06:05 +00:00
Marc Zyngier
4340ba80bd arm64: KVM: Move BP hardening vectors into .hyp.text section
There is no reason why the BP hardening vectors shouldn't be part
of the HYP text at compile time, rather than being mapped at runtime.

Also introduce a new config symbol that controls the compilation
of bpi.S.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 13:05:49 +00:00
Marc Zyngier
3c5e81232e arm64: KVM: Move vector offsetting from hyp-init.S to kvm_get_hyp_vector
We currently provide the hyp-init code with a kernel VA, and expect
it to turn it into a HYP va by itself. As we're about to provide
the hypervisor with mappings that are not necessarily in the memory
range, let's move the kern_hyp_va macro to kvm_get_hyp_vector.

No functionnal change.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 13:05:37 +00:00
Marc Zyngier
ed57cac83e arm64: KVM: Introduce EL2 VA randomisation
The main idea behind randomising the EL2 VA is that we usually have
a few spare bits between the most significant bit of the VA mask
and the most significant bit of the linear mapping.

Those bits could be a bunch of zeroes, and could be useful
to move things around a bit. Of course, the more memory you have,
the less randomisation you get...

Alternatively, these bits could be the result of KASLR, in which
case they are already random. But it would be nice to have a
*different* randomization, just to make the job of a potential
attacker a bit more difficult.

Inserting these random bits is a bit involved. We don't have a spare
register (short of rewriting all the kern_hyp_va call sites), and
the immediate we want to insert is too random to be used with the
ORR instruction. The best option I could come up with is the following
sequence:

	and x0, x0, #va_mask
	ror x0, x0, #first_random_bit
	add x0, x0, #(random & 0xfff)
	add x0, x0, #(random >> 12), lsl #12
	ror x0, x0, #(63 - first_random_bit)

making it a fairly long sequence, but one that a decent CPU should
be able to execute without breaking a sweat. It is of course NOPed
out on VHE. The last 4 instructions can also be turned into NOPs
if it appears that there is no free bits to use.

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>
2018-03-19 13:05:22 +00:00
Marc Zyngier
1bb32a44ae KVM: arm/arm64: Keep GICv2 HYP VAs in kvm_vgic_global_state
As we're about to change the way we map devices at HYP, we need
to move away from kern_hyp_va on an IO address.

One way of achieving this is to store the VAs in kvm_vgic_global_state,
and use that directly from the HYP code. This requires a small change
to create_hyp_io_mappings so that it can also return a HYP VA.

We take this opportunity to nuke the vctrl_base field in the emulated
distributor, as it is not used anymore.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 13:04:06 +00:00
Marc Zyngier
807a378425 KVM: arm/arm64: Move ioremap calls to create_hyp_io_mappings
Both HYP io mappings call ioremap, followed by create_hyp_io_mappings.
Let's move the ioremap call into create_hyp_io_mappings itself, which
simplifies the code a bit and allows for further refactoring.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 13:03:47 +00:00
Marc Zyngier
44a497abd6 KVM: arm/arm64: Do not use kern_hyp_va() with kvm_vgic_global_state
kvm_vgic_global_state is part of the read-only section, and is
usually accessed using a PC-relative address generation (adrp + add).

It is thus useless to use kern_hyp_va() on it, and actively problematic
if kern_hyp_va() becomes non-idempotent. On the other hand, there is
no way that the compiler is going to guarantee that such access is
always PC relative.

So let's bite the bullet and provide our own accessor.

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>
2018-03-19 13:03:33 +00:00
Marc Zyngier
2b4d1606aa arm64: KVM: Dynamically patch the kernel/hyp VA mask
So far, we're using a complicated sequence of alternatives to
patch the kernel/hyp VA mask on non-VHE, and NOP out the
masking altogether when on VHE.

The newly introduced dynamic patching gives us the opportunity
to simplify that code by patching a single instruction with
the correct mask (instead of the mind bending cumulative masking
we have at the moment) or even a single NOP on VHE. This also
adds some initial code that will allow the patching callback
to switch to a more complex patching.

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>
2018-03-19 13:03:29 +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
Will Deacon
20a004e7b0 arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables
In many cases, page tables can be accessed concurrently by either another
CPU (due to things like fast gup) or by the hardware page table walker
itself, which may set access/dirty bits. In such cases, it is important
to use READ_ONCE/WRITE_ONCE when accessing page table entries so that
entries cannot be torn, merged or subject to apparent loss of coherence
due to compiler transformations.

Whilst there are some scenarios where this cannot happen (e.g. pinned
kernel mappings for the linear region), the overhead of using READ_ONCE
/WRITE_ONCE everywhere is minimal and makes the code an awful lot easier
to reason about. This patch consistently uses these macros in the arch
code, as well as explicitly namespacing pointers to page table entries
from the entries themselves by using adopting a 'p' suffix for the former
(as is sometimes used elsewhere in the kernel source).

Tested-by: Yury Norov <ynorov@caviumnetworks.com>
Tested-by: Richard Ruigrok <rruigrok@codeaurora.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-16 18:13:57 +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
6840bdd73d arm64: KVM: Use per-CPU vector when BP hardening is enabled
Now that we have per-CPU vectors, let's plug then in the KVM/arm64 code.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-08 18:46:56 +00:00
Marc Zyngier
17ab9d57de KVM: arm/arm64: Drop vcpu parameter from guest cache maintenance operartions
The vcpu parameter isn't used for anything, and gets in the way of
further cleanups. Let's get rid of it.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-08 15:20:46 +01:00
Marc Zyngier
7a3796d2ef KVM: arm/arm64: Preserve Exec permission across R/W permission faults
So far, we loose the Exec property whenever we take permission
faults, as we always reconstruct the PTE/PMD from scratch. This
can be counter productive as we can end-up with the following
fault sequence:

	X -> RO -> ROX -> RW -> RWX

Instead, we can lookup the existing PTE/PMD and clear the XN bit in the
new entry if it was already cleared in the old one, leadig to a much
nicer fault sequence:

	X -> ROX -> RWX

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-08 15:20:46 +01:00
Marc Zyngier
d0e22b4ac3 KVM: arm/arm64: Limit icache invalidation to prefetch aborts
We've so far eagerly invalidated the icache, no matter how
the page was faulted in (data or prefetch abort).

But we can easily track execution by setting the XN bits
in the S2 page tables, get the prefetch abort at HYP and
perform the icache invalidation at that time only.

As for most VMs, the instruction working set is pretty
small compared to the data set, this is likely to save
some traffic (specially as the invalidation is broadcast).

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-08 15:20:45 +01:00
Marc Zyngier
4fee947366 arm64: KVM: Add invalidate_icache_range helper
We currently tightly couple dcache clean with icache invalidation,
but KVM could do without the initial flush to PoU, as we've
already flushed things to PoC.

Let's introduce invalidate_icache_range which is limited to
invalidating the icache from the linear mapping (and thus
has none of the userspace fault handling complexity), and
wire it in KVM instead of flush_icache_range.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-08 15:20:43 +01:00
Marc Zyngier
a15f693935 KVM: arm/arm64: Split dcache/icache flushing
As we're about to introduce opportunistic invalidation of the icache,
let's split dcache and icache flushing.

Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-08 15:20:43 +01:00
Kristina Martsenko
fa2a8445b1 arm64: allow ID map to be extended to 52 bits
Currently, when using VA_BITS < 48, if the ID map text happens to be
placed in physical memory above VA_BITS, we increase the VA size (up to
48) and create a new table level, in order to map in the ID map text.
This is okay because the system always supports 48 bits of VA.

This patch extends the code such that if the system supports 52 bits of
VA, and the ID map text is placed that high up, then we increase the VA
size accordingly, up to 52.

One difference from the current implementation is that so far the
condition of VA_BITS < 48 has meant that the top level table is always
"full", with the maximum number of entries, and an extra table level is
always needed. Now, when VA_BITS = 48 (and using 64k pages), the top
level table is not full, and we simply need to increase the number of
entries in it, instead of creating a new table level.

Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: reduce arguments to __create_hyp_mappings()]
[catalin.marinas@arm.com: reworked/renamed __cpu_uses_extended_idmap_level()]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22 17:37:33 +00:00
Kristina Martsenko
75387b9263 arm64: handle 52-bit physical addresses in page table entries
The top 4 bits of a 52-bit physical address are positioned at bits
12..15 of a page table entry. Introduce macros to convert between a
physical address and its placement in a table entry, and change all
macros/functions that access PTEs to use them.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: some long lines wrapped]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22 17:37:18 +00:00
Kristina Martsenko
193383043f arm64: don't open code page table entry creation
Instead of open coding the generation of page table entries, use the
macros/functions that exist for this - pfn_p*d and p*d_populate. Most
code in the kernel already uses these macros, this patch tries to fix
up the few places that don't. This is useful for the next patch in this
series, which needs to change the page table entry logic, and it's
better to have that logic in one place.

The KVM extended ID map is special, since we're creating a level above
CONFIG_PGTABLE_LEVELS and the required function isn't available. Leave
it as is and add a comment to explain it. (The normal kernel ID map code
doesn't need this change because its page tables are created in assembly
(__create_page_tables)).

Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22 17:36:34 +00:00
Kristina Martsenko
529c4b05a3 arm64: handle 52-bit addresses in TTBR
The top 4 bits of a 52-bit physical address are positioned at bits 2..5
in the TTBR registers. Introduce a couple of macros to move the bits
there, and change all TTBR writers to use them.

Leave TTBR0 PAN code unchanged, to avoid complicating it. A system with
52-bit PA will have PAN anyway (because it's ARMv8.1 or later), and a
system without 52-bit PA can only use up to 48-bit PAs. A later patch in
this series will add a kconfig dependency to ensure PAN is configured.

In addition, when using 52-bit PA there is a special alignment
requirement on the top-level table. We don't currently have any VA_BITS
configuration that would violate the requirement, but one could be added
in the future, so add a compile-time BUG_ON to check for it.

Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: added TTBR_BADD_MASK_52 comment]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22 17:35:21 +00:00
Catalin Marinas
0966253d7c kvm: arm64: Convert kvm_set_s2pte_readonly() from inline asm to cmpxchg()
To take advantage of the LSE atomic instructions and also make the code
cleaner, convert the kvm_set_s2pte_readonly() function to use the more
generic cmpxchg().

Cc: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-08-21 11:12:39 +01:00
Linus Torvalds
2d3e4866de * ARM: HYP mode stub supports kexec/kdump on 32-bit; improved PMU
support; virtual interrupt controller performance improvements; support
 for userspace virtual interrupt controller (slower, but necessary for
 KVM on the weird Broadcom SoCs used by the Raspberry Pi 3)
 
 * MIPS: basic support for hardware virtualization (ImgTec
 P5600/P6600/I6400 and Cavium Octeon III)
 
 * PPC: in-kernel acceleration for VFIO
 
 * s390: support for guests without storage keys; adapter interruption
 suppression
 
 * x86: usual range of nVMX improvements, notably nested EPT support for
 accessed and dirty bits; emulation of CPL3 CPUID faulting
 
 * generic: first part of VCPU thread request API; kvm_stat improvements
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "ARM:
   - HYP mode stub supports kexec/kdump on 32-bit
   - improved PMU support
   - virtual interrupt controller performance improvements
   - support for userspace virtual interrupt controller (slower, but
     necessary for KVM on the weird Broadcom SoCs used by the Raspberry
     Pi 3)

  MIPS:
   - basic support for hardware virtualization (ImgTec P5600/P6600/I6400
     and Cavium Octeon III)

  PPC:
   - in-kernel acceleration for VFIO

  s390:
   - support for guests without storage keys
   - adapter interruption suppression

  x86:
   - usual range of nVMX improvements, notably nested EPT support for
     accessed and dirty bits
   - emulation of CPL3 CPUID faulting

  generic:
   - first part of VCPU thread request API
   - kvm_stat improvements"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (227 commits)
  kvm: nVMX: Don't validate disabled secondary controls
  KVM: put back #ifndef CONFIG_S390 around kvm_vcpu_kick
  Revert "KVM: Support vCPU-based gfn->hva cache"
  tools/kvm: fix top level makefile
  KVM: x86: don't hold kvm->lock in KVM_SET_GSI_ROUTING
  KVM: Documentation: remove VM mmap documentation
  kvm: nVMX: Remove superfluous VMX instruction fault checks
  KVM: x86: fix emulation of RSM and IRET instructions
  KVM: mark requests that need synchronization
  KVM: return if kvm_vcpu_wake_up() did wake up the VCPU
  KVM: add explicit barrier to kvm_vcpu_kick
  KVM: perform a wake_up in kvm_make_all_cpus_request
  KVM: mark requests that do not need a wakeup
  KVM: remove #ifndef CONFIG_S390 around kvm_vcpu_wake_up
  KVM: x86: always use kvm_make_request instead of set_bit
  KVM: add kvm_{test,clear}_request to replace {test,clear}_bit
  s390: kvm: Cpu model support for msa6, msa7 and msa8
  KVM: x86: remove irq disablement around KVM_SET_CLOCK/KVM_GET_CLOCK
  kvm: better MWAIT emulation for guests
  KVM: x86: virtualize cpuid faulting
  ...
2017-05-08 12:37:56 -07:00
Marc Zyngier
9e9ebd01a3 arm/arm64: KVM: Remove kvm_get_idmap_start
With __cpu_reset_hyp_mode having become fairly dumb, there is no
need for kvm_get_idmap_start anymore.

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
Dave Martin
46823dd17c arm64: cpufeature: Make ID reg accessor naming less counterintuitive
read_system_reg() can readily be confused with read_sysreg(),
whereas these are really quite different in their meaning.

This patches attempts to reduce the ambiguity be reserving "sysreg"
for the actual system register accessors.

read_system_reg() is instead renamed to read_sanitised_ftr_reg(),
to make it more obvious that the Linux-defined sanitised feature
register cache is being accessed here, not the underlying
architectural system registers.

cpufeature.c's internal __raw_read_system_reg() function is renamed
in line with its actual purpose: a form of read_sysreg() that
indexes on (non-compiletime-constant) encoding rather than symbolic
register name.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-04-04 16:55:41 +01:00
Will Deacon
87da236ebc arm64: KVM: Add support for VPIPT I-caches
A VPIPT I-cache has two main properties:

1. Lines allocated into the cache are tagged by VMID and a lookup can
   only hit lines that were allocated with the current VMID.

2. I-cache invalidation from EL1/0 only invalidates lines that match the
   current VMID of the CPU doing the invalidation.

This can cause issues with non-VHE configurations, where the host runs
at EL1 and wants to invalidate I-cache entries for a guest running with
a different VMID. VHE is not affected, because the host runs at EL2 and
I-cache invalidation applies as expected.

This patch solves the problem by invalidating the I-cache when unmapping
a page at stage 2 on a system with a VPIPT I-cache but not running with
VHE enabled. Hopefully this is an obscure enough configuration that the
overhead isn't anything to worry about, although it does mean that the
by-range I-cache invalidation currently performed when mapping at stage
2 can be elided on such systems, because the I-cache will be clean for
the guest VMID following a rollover event.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-20 16:25:45 +00:00
Will Deacon
02f7760e6e arm64: cache: Merge cachetype.h into cache.h
cachetype.h and cache.h are small and both obviously related to caches.
Merge them together to reduce clutter.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-20 16:16:59 +00:00
Will Deacon
155433cb36 arm64: cache: Remove support for ASID-tagged VIVT I-caches
As a recent change to ARMv8, ASID-tagged VIVT I-caches are removed
retrospectively from the architecture. Consequently, we don't need to
support them in Linux either.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-20 16:16:57 +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
Marc Zyngier
13b7756cec arm/arm64: KVM: Stop propagating cacheability status of a faulted page
Now that we unconditionally flush newly mapped pages to the PoC,
there is no need to care about the "uncached" status of individual
pages - they must all be visible all the way down.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-30 13:47:38 +00:00
Marc Zyngier
8f36ebaf21 arm/arm64: KVM: Enforce unconditional flush to PoC when mapping to stage-2
When we fault in a page, we flush it to the PoC (Point of Coherency)
if the faulting vcpu has its own caches off, so that it can observe
the page we just brought it.

But if the vcpu has its caches on, we skip that step. Bad things
happen when *another* vcpu tries to access that page with its own
caches disabled. At that point, there is no garantee that the
data has made it to the PoC, and we access stale data.

The obvious fix is to always flush to PoC when a page is faulted
in, no matter what the state of the vcpu is.

Cc: stable@vger.kernel.org
Fixes: 2d58b733c8 ("arm64: KVM: force cache clean on page fault when caches are off")
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-30 13:47:37 +00:00
Laura Abbott
2077be6783 arm64: Use __pa_symbol for kernel symbols
__pa_symbol is technically the marcro that should be used for kernel
symbols. Switch to this as a pre-requisite for DEBUG_VIRTUAL which
will do bounds checking.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-01-12 15:05:39 +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
Linus Torvalds
6218590bcb KVM updates for v4.9-rc1
All architectures:
   Move `make kvmconfig` stubs from x86;  use 64 bits for debugfs stats.
 
 ARM:
   Important fixes for not using an in-kernel irqchip; handle SError
   exceptions and present them to guests if appropriate; proxying of GICV
   access at EL2 if guest mappings are unsafe; GICv3 on AArch32 on ARMv8;
   preparations for GICv3 save/restore, including ABI docs; cleanups and
   a bit of optimizations.
 
 MIPS:
   A couple of fixes in preparation for supporting MIPS EVA host kernels;
   MIPS SMP host & TLB invalidation fixes.
 
 PPC:
   Fix the bug which caused guests to falsely report lockups; other minor
   fixes; a small optimization.
 
 s390:
   Lazy enablement of runtime instrumentation; up to 255 CPUs for nested
   guests; rework of machine check deliver; cleanups and fixes.
 
 x86:
   IOMMU part of AMD's AVIC for vmexit-less interrupt delivery; Hyper-V
   TSC page; per-vcpu tsc_offset in debugfs; accelerated INS/OUTS in
   nVMX; cleanups and fixes.
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Merge tag 'kvm-4.9-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Radim Krčmář:
 "All architectures:
   - move `make kvmconfig` stubs from x86
   - use 64 bits for debugfs stats

  ARM:
   - Important fixes for not using an in-kernel irqchip
   - handle SError exceptions and present them to guests if appropriate
   - proxying of GICV access at EL2 if guest mappings are unsafe
   - GICv3 on AArch32 on ARMv8
   - preparations for GICv3 save/restore, including ABI docs
   - cleanups and a bit of optimizations

  MIPS:
   - A couple of fixes in preparation for supporting MIPS EVA host
     kernels
   - MIPS SMP host & TLB invalidation fixes

  PPC:
   - Fix the bug which caused guests to falsely report lockups
   - other minor fixes
   - a small optimization

  s390:
   - Lazy enablement of runtime instrumentation
   - up to 255 CPUs for nested guests
   - rework of machine check deliver
   - cleanups and fixes

  x86:
   - IOMMU part of AMD's AVIC for vmexit-less interrupt delivery
   - Hyper-V TSC page
   - per-vcpu tsc_offset in debugfs
   - accelerated INS/OUTS in nVMX
   - cleanups and fixes"

* tag 'kvm-4.9-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (140 commits)
  KVM: MIPS: Drop dubious EntryHi optimisation
  KVM: MIPS: Invalidate TLB by regenerating ASIDs
  KVM: MIPS: Split kernel/user ASID regeneration
  KVM: MIPS: Drop other CPU ASIDs on guest MMU changes
  KVM: arm/arm64: vgic: Don't flush/sync without a working vgic
  KVM: arm64: Require in-kernel irqchip for PMU support
  KVM: PPC: Book3s PR: Allow access to unprivileged MMCR2 register
  KVM: PPC: Book3S PR: Support 64kB page size on POWER8E and POWER8NVL
  KVM: PPC: Book3S: Remove duplicate setting of the B field in tlbie
  KVM: PPC: BookE: Fix a sanity check
  KVM: PPC: Book3S HV: Take out virtual core piggybacking code
  KVM: PPC: Book3S: Treat VTB as a per-subcore register, not per-thread
  ARM: gic-v3: Work around definition of gic_write_bpr1
  KVM: nVMX: Fix the NMI IDT-vectoring handling
  KVM: VMX: Enable MSR-BASED TPR shadow even if APICv is inactive
  KVM: nVMX: Fix reload apic access page warning
  kvmconfig: add virtio-gpu to config fragment
  config: move x86 kvm_guest.config to a common location
  arm64: KVM: Remove duplicating init code for setting VMID
  ARM: KVM: Support vgic-v3
  ...
2016-10-06 10:49:01 -07:00
Mark Rutland
e506236a7b arm64/kvm: use alternative auto-nop
Make use of the new alternative_if and alternative_else_nop_endif and
get rid of our open-coded NOP sleds, making the code simpler to read.

Note that for __kvm_call_hyp the branch to __vhe_hyp_call has been moved
out of the alternative sequence, and in the default case there will be
four additional NOPs executed.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: kvmarm@lists.cs.columbia.edu
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-12 10:46:07 +01:00
Mark Rutland
777c155772 arm64/kvm: remove unused stub functions
Now that 32-bit KVM no longer performs cache maintenance for page table
updates, we no longer need empty stubs for arm64. Remove them.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: kvmarm@lists.cs.columbia.edu
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08 12:53:00 +02:00
Marc Zyngier
6c41a413fd arm/arm64: Get rid of KERN_TO_HYP
We have both KERN_TO_HYP and kern_hyp_va, which do the exact same
thing. Let's standardize on the latter.

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
f7bec68d2f arm/arm64: KVM: Prune unused #defines
We can now remove a number of dead #defines, thanks to the trampoline
code being gone.

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
26781f9ce1 arm/arm64: KVM: Kill free_boot_hyp_pgd
There is no way to free the boot PGD, because it doesn't exist
anymore as a standalone entity.

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
fd81e6bf39 arm64: KVM: Refactor kern_hyp_va to deal with multiple offsets
As we move towards a selectable HYP VA range, it is obvious that
we don't want to test a variable to find out if we need to use
the bottom VA range, the top VA range, or use the address as is
(for VHE).

Instead, we can expand our current helper to generate the right
mask or nop with code patching. We default to using the top VA
space, with alternatives to switch to the bottom one or to nop
out the instructions.

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