linux.git/arch/mips/kvm, branch v5.17.6

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

2022-02-05T17:55:59+00:00

Pull kvm fixes from Paolo Bonzini:
 "ARM:

   - A couple of fixes when handling an exception while a SError has
     been delivered

   - Workaround for Cortex-A510's single-step erratum

  RISC-V:

   - Make CY, TM, and IR counters accessible in VU mode

   - Fix SBI implementation version

  x86:

   - Report deprecation of x87 features in supported CPUID

   - Preparation for fixing an interrupt delivery race on AMD hardware

   - Sparse fix

  All except POWER and s390:

   - Rework guest entry code to correctly mark noinstr areas and fix
     vtime' accounting (for x86, this was already mostly correct but not
     entirely; for ARM, MIPS and RISC-V it wasn't)"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: Use ERR_PTR_USR() to return -EFAULT as a __user pointer
  KVM: x86: Report deprecated x87 features in supported CPUID
  KVM: arm64: Workaround Cortex-A510's single-step and PAC trap errata
  KVM: arm64: Stop handle_exit() from handling HVC twice when an SError occurs
  KVM: arm64: Avoid consuming a stale esr value when SError occur
  RISC-V: KVM: Fix SBI implementation version
  RISC-V: KVM: make CY, TM, and IR counters accessible in VU mode
  kvm/riscv: rework guest entry logic
  kvm/arm64: rework guest entry logic
  kvm/x86: rework guest entry logic
  kvm/mips: rework guest entry logic
  kvm: add guest_state_{enter,exit}_irqoff()
  KVM: x86: Move delivery of non-APICv interrupt into vendor code
  kvm: Move KVM_GET_XSAVE2 IOCTL definition at the end of kvm.h

kvm/mips: rework guest entry logic

2022-02-01T13:51:53+00:00

In kvm_arch_vcpu_ioctl_run() we use guest_enter_irqoff() and
guest_exit_irqoff() directly, with interrupts masked between these. As
we don't handle any timer ticks during this window, we will not account
time spent within the guest as guest time, which is unfortunate.

Additionally, we do not inform lockdep or tracing that interrupts will
be enabled during guest execution, which caan lead to misleading traces
and warnings that interrupts have been enabled for overly-long periods.

This patch fixes these issues by using the new timing and context
entry/exit helpers to ensure that interrupts are handled during guest
vtime but with RCU watching, with a sequence:

	guest_timing_enter_irqoff();

	guest_state_enter_irqoff();
	< run the vcpu >
	guest_state_exit_irqoff();

	< take any pending IRQs >

	guest_timing_exit_irqoff();

In addition, as guest exits during the "run the vcpu" step are handled
by kvm_mips_handle_exit(), a wrapper function is added which ensures
that such exists are handled with a sequence:

	guest_state_exit_irqoff();
	< handle the exit >
	guest_state_enter_irqoff();

This means that exits which stop the vCPU running will have a redundant
guest_state_enter_irqoff() .. guest_state_exit_irqoff() sequence, which
can be addressed with future rework.

Since instrumentation may make use of RCU, we must also ensure that no
instrumented code is run during the EQS. I've split out the critical
section into a new kvm_mips_enter_exit_vcpu() helper which is marked
noinstr.

Signed-off-by: Mark Rutland 
Cc: Aleksandar Markovic 
Cc: Frederic Weisbecker 
Cc: Huacai Chen 
Cc: Paolo Bonzini 
Cc: Paul E. McKenney 
Cc: Thomas Bogendoerfer 
Message-Id: <20220201132926.3301912-6-mark.rutland@arm.com>
Signed-off-by: Paolo Bonzini

MIPS: KVM: fix vz.c kernel-doc notation

2022-02-01T07:36:27+00:00

Fix all kernel-doc warnings in mips/kvm/vz.c as reported by the
kernel test robot:

  arch/mips/kvm/vz.c:471: warning: Function parameter or member 'out_compare' not described in '_kvm_vz_save_htimer'
  arch/mips/kvm/vz.c:471: warning: Function parameter or member 'out_cause' not described in '_kvm_vz_save_htimer'
  arch/mips/kvm/vz.c:471: warning: Excess function parameter 'compare' description in '_kvm_vz_save_htimer'
  arch/mips/kvm/vz.c:471: warning: Excess function parameter 'cause' description in '_kvm_vz_save_htimer'
  arch/mips/kvm/vz.c:1551: warning: No description found for return value of 'kvm_trap_vz_handle_cop_unusable'
  arch/mips/kvm/vz.c:1552: warning: expecting prototype for kvm_trap_vz_handle_cop_unusuable(). Prototype was for kvm_trap_vz_handle_cop_unusable() instead
  arch/mips/kvm/vz.c:1597: warning: No description found for return value of 'kvm_trap_vz_handle_msa_disabled'

Fixes: c992a4f6a9b0 ("KVM: MIPS: Implement VZ support")
Fixes: f4474d50c7d4 ("KVM: MIPS/VZ: Support hardware guest timer")
Signed-off-by: Randy Dunlap 
Reported-by: kernel test robot 
Cc: Thomas Bogendoerfer 
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen 
Cc: Aleksandar Markovic 
Cc: James Hogan 
Cc: kvm@vger.kernel.org
Signed-off-by: Thomas Bogendoerfer

KVM: mips: Use Makefile.kvm for common files

2021-12-09T17:58:37+00:00

Signed-off-by: David Woodhouse 
Message-Id: <20211121125451.9489-5-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini

KVM: Rename kvm_vcpu_block() => kvm_vcpu_halt()

2021-12-08T09:24:51+00:00

Rename kvm_vcpu_block() to kvm_vcpu_halt() in preparation for splitting
the actual "block" sequences into a separate helper (to be named
kvm_vcpu_block()).  x86 will use the standalone block-only path to handle
non-halt cases where the vCPU is not runnable.

Rename block_ns to halt_ns to match the new function name.

No functional change intended.

Reviewed-by: David Matlack 
Reviewed-by: Christian Borntraeger 
Signed-off-by: Sean Christopherson 
Message-Id: <20211009021236.4122790-14-seanjc@google.com>
Signed-off-by: Paolo Bonzini

KVM: Use interval tree to do fast hva lookup in memslots

2021-12-08T09:24:32+00:00

The current memslots implementation only allows quick binary search by gfn,
quick lookup by hva is not possible - the implementation has to do a linear
scan of the whole memslots array, even though the operation being performed
might apply just to a single memslot.

This significantly hurts performance of per-hva operations with higher
memslot counts.

Since hva ranges can overlap between memslots an interval tree is needed
for tracking them.

[sean: handle interval tree updates in kvm_replace_memslot()]
Signed-off-by: Maciej S. Szmigiero 
Message-Id:

KVM: Stop passing kvm_userspace_memory_region to arch memslot hooks

2021-12-08T09:24:25+00:00

Drop the @mem param from kvm_arch_{prepare,commit}_memory_region() now
that its use has been removed in all architectures.

No functional change intended.

Signed-off-by: Sean Christopherson 
Reviewed-by: Maciej S. Szmigiero 
Signed-off-by: Maciej S. Szmigiero 
Message-Id:

KVM: MIPS: Drop pr_debug from memslot commit to avoid using "mem"

2021-12-08T09:24:21+00:00

Remove an old (circa 2012) kvm_debug from kvm_arch_commit_memory_region()
to print basic information when committing a memslot change.  The primary
motivation for removing the kvm_debug is to avoid using @mem, the user
memory region, so that said param can be removed.

Alternatively, the debug message could be converted to use @new, but that
would require synthesizing select state to play nice with the DELETED
case, which will pass NULL for @new in the future.  And there's no
argument to be had for dumping generic information in an arch callback,
i.e. if there's a good reason for the debug message, then it belongs in
common KVM code where all architectures can benefit.

Signed-off-by: Sean Christopherson 
Signed-off-by: Maciej S. Szmigiero 
Message-Id: <446929a668f6e1346751571b71db41e94e976cdf.1638817639.git.maciej.szmigiero@oracle.com>

KVM: Let/force architectures to deal with arch specific memslot data

2021-12-08T09:24:20+00:00

Pass the "old" slot to kvm_arch_prepare_memory_region() and force arch
code to handle propagating arch specific data from "new" to "old" when
necessary.  This is a baby step towards dynamically allocating "new" from
the get go, and is a (very) minor performance boost on x86 due to not
unnecessarily copying arch data.

For PPC HV, copy the rmap in the !CREATE and !DELETE paths, i.e. for MOVE
and FLAGS_ONLY.  This is functionally a nop as the previous behavior
would overwrite the pointer for CREATE, and eventually discard/ignore it
for DELETE.

For x86, copy the arch data only for FLAGS_ONLY changes.  Unlike PPC HV,
x86 needs to reallocate arch data in the MOVE case as the size of x86's
allocations depend on the alignment of the memslot's gfn.

Opportunistically tweak kvm_arch_prepare_memory_region()'s param order to
match the "commit" prototype.

Signed-off-by: Sean Christopherson 
Reviewed-by: Maciej S. Szmigiero 
[mss: add missing RISCV kvm_arch_prepare_memory_region() change]
Signed-off-by: Maciej S. Szmigiero 
Message-Id: <67dea5f11bbcfd71e3da5986f11e87f5dd4013f9.1638817639.git.maciej.szmigiero@oracle.com>

KVM: mips: Use kvm_get_vcpu() instead of open-coded access

2021-12-08T09:24:13+00:00

As we are about to change the way vcpus are allocated, mandate
the use of kvm_get_vcpu() instead of open-coding the access.

Reviewed-by: Philippe Mathieu-Daudé 
Signed-off-by: Marc Zyngier 
Message-Id: <20211116160403.4074052-3-maz@kernel.org>
Signed-off-by: Paolo Bonzini