linux.git/arch/mips/kvm, branch v4.19.258

KVM: MIPS: Change the definition of kvm type

2020-09-23T10:10:59+00:00

[ Upstream commit 15e9e35cd1dec2bc138464de6bf8ef828df19235 ]

MIPS defines two kvm types:

 #define KVM_VM_MIPS_TE          0
 #define KVM_VM_MIPS_VZ          1

In Documentation/virt/kvm/api.rst it is said that "You probably want to
use 0 as machine type", which implies that type 0 be the "automatic" or
"default" type. And, in user-space libvirt use the null-machine (with
type 0) to detect the kvm capability, which returns "KVM not supported"
on a VZ platform.

I try to fix it in QEMU but it is ugly:
https://lists.nongnu.org/archive/html/qemu-devel/2020-08/msg05629.html

And Thomas Huth suggests me to change the definition of kvm type:
https://lists.nongnu.org/archive/html/qemu-devel/2020-09/msg03281.html

So I define like this:

 #define KVM_VM_MIPS_AUTO        0
 #define KVM_VM_MIPS_VZ          1
 #define KVM_VM_MIPS_TE          2

Since VZ and TE cannot co-exists, using type 0 on a TE platform will
still return success (so old user-space tools have no problems on new
kernels); the advantage is that using type 0 on a VZ platform will not
return failure. So, the only problem is "new user-space tools use type
2 on old kernels", but if we treat this as a kernel bug, we can backport
this patch to old stable kernels.

Signed-off-by: Huacai Chen 
Message-Id: <1599734031-28746-1-git-send-email-chenhc@lemote.com>
Signed-off-by: Paolo Bonzini 
Signed-off-by: Sasha Levin

KVM: Pass MMU notifier range flags to kvm_unmap_hva_range()

2020-08-26T08:31:07+00:00

commit fdfe7cbd58806522e799e2a50a15aee7f2cbb7b6 upstream.

The 'flags' field of 'struct mmu_notifier_range' is used to indicate
whether invalidate_range_{start,end}() are permitted to block. In the
case of kvm_mmu_notifier_invalidate_range_start(), this field is not
forwarded on to the architecture-specific implementation of
kvm_unmap_hva_range() and therefore the backend cannot sensibly decide
whether or not to block.

Add an extra 'flags' parameter to kvm_unmap_hva_range() so that
architectures are aware as to whether or not they are permitted to block.

Cc: 
Cc: Marc Zyngier 
Cc: Suzuki K Poulose 
Cc: James Morse 
Signed-off-by: Will Deacon 
Message-Id: <20200811102725.7121-2-will@kernel.org>
Signed-off-by: Paolo Bonzini 
[will: Backport to 4.19; use 'blockable' instead of non-existent range flags]
Signed-off-by: Will Deacon 
Signed-off-by: Greg Kroah-Hartman

KVM: s390: Do not report unusabled IDs via KVM_CAP_MAX_VCPU_ID

2019-06-09T07:17:18+00:00

commit a86cb413f4bf273a9d341a3ab2c2ca44e12eb317 upstream.

KVM_CAP_MAX_VCPU_ID is currently always reporting KVM_MAX_VCPU_ID on all
architectures. However, on s390x, the amount of usable CPUs is determined
during runtime - it is depending on the features of the machine the code
is running on. Since we are using the vcpu_id as an index into the SCA
structures that are defined by the hardware (see e.g. the sca_add_vcpu()
function), it is not only the amount of CPUs that is limited by the hard-
ware, but also the range of IDs that we can use.
Thus KVM_CAP_MAX_VCPU_ID must be determined during runtime on s390x, too.
So the handling of KVM_CAP_MAX_VCPU_ID has to be moved from the common
code into the architecture specific code, and on s390x we have to return
the same value here as for KVM_CAP_MAX_VCPUS.
This problem has been discovered with the kvm_create_max_vcpus selftest.
With this change applied, the selftest now passes on s390x, too.

Reviewed-by: Andrew Jones 
Reviewed-by: Cornelia Huck 
Reviewed-by: David Hildenbrand 
Signed-off-by: Thomas Huth 
Message-Id: <20190523164309.13345-9-thuth@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Christian Borntraeger 
Signed-off-by: Greg Kroah-Hartman

KVM: Remove obsolete kvm_unmap_hva notifier backend

2018-09-07T13:06:02+00:00

kvm_unmap_hva is long gone, and we only have kvm_unmap_hva_range to
deal with. Drop the now obsolete code.

Fixes: fb1522e099f0 ("KVM: update to new mmu_notifier semantic v2")
Cc: James Hogan 
Reviewed-by: Paolo Bonzini 
Signed-off-by: Marc Zyngier 
Signed-off-by: Christoffer Dall

sched/swait: Rename to exclusive

2018-06-20T09:35:56+00:00

Since swait basically implemented exclusive waits only, make sure
the API reflects that.

  $ git grep -l -e "\"
		-e "\" | while read file;
    do
	sed -i -e 's/\/&_one/g'
	       -e 's/\/&_exclusive/g' $file;
    done

With a few manual touch-ups.

Suggested-by: Linus Torvalds 
Signed-off-by: Peter Zijlstra (Intel) 
Signed-off-by: Thomas Gleixner 
Acked-by: Linus Torvalds 
Cc: bigeasy@linutronix.de
Cc: oleg@redhat.com
Cc: paulmck@linux.vnet.ibm.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180612083909.261946548@infradead.org

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

2018-06-12T18:34:04+00:00

Pull KVM updates from Paolo Bonzini:
 "Small update for KVM:

  ARM:
   - lazy context-switching of FPSIMD registers on arm64
   - "split" regions for vGIC redistributor

  s390:
   - cleanups for nested
   - clock handling
   - crypto
   - storage keys
   - control register bits

  x86:
   - many bugfixes
   - implement more Hyper-V super powers
   - implement lapic_timer_advance_ns even when the LAPIC timer is
     emulated using the processor's VMX preemption timer.
   - two security-related bugfixes at the top of the branch"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (79 commits)
  kvm: fix typo in flag name
  kvm: x86: use correct privilege level for sgdt/sidt/fxsave/fxrstor access
  KVM: x86: pass kvm_vcpu to kvm_read_guest_virt and kvm_write_guest_virt_system
  KVM: x86: introduce linear_{read,write}_system
  kvm: nVMX: Enforce cpl=0 for VMX instructions
  kvm: nVMX: Add support for "VMWRITE to any supported field"
  kvm: nVMX: Restrict VMX capability MSR changes
  KVM: VMX: Optimize tscdeadline timer latency
  KVM: docs: nVMX: Remove known limitations as they do not exist now
  KVM: docs: mmu: KVM support exposing SLAT to guests
  kvm: no need to check return value of debugfs_create functions
  kvm: Make VM ioctl do valloc for some archs
  kvm: Change return type to vm_fault_t
  KVM: docs: mmu: Fix link to NPT presentation from KVM Forum 2008
  kvm: x86: Amend the KVM_GET_SUPPORTED_CPUID API documentation
  KVM: x86: hyperv: declare KVM_CAP_HYPERV_TLBFLUSH capability
  KVM: x86: hyperv: simplistic HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}_EX implementation
  KVM: x86: hyperv: simplistic HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE} implementation
  KVM: introduce kvm_make_vcpus_request_mask() API
  KVM: x86: hyperv: do rep check for each hypercall separately
  ...

kvm: Change return type to vm_fault_t

2018-06-01T17:18:25+00:00

Use new return type vm_fault_t for fault handler. For
now, this is just documenting that the function returns
a VM_FAULT value rather than an errno. Once all instances
are converted, vm_fault_t will become a distinct type.

commit 1c8f422059ae ("mm: change return type to vm_fault_t")

Signed-off-by: Souptick Joarder 
Reviewed-by: Matthew Wilcox 
Signed-off-by: Paolo Bonzini

KVM: Fix spelling mistake: "cop_unsuable" -> "cop_unusable"

2018-05-14T22:54:25+00:00

Trivial fix to spelling mistake in debugfs_entries text.

Fixes: 669e846e6c4e ("KVM/MIPS32: MIPS arch specific APIs for KVM")
Signed-off-by: Colin Ian King 
Cc: Ralf Baechle 
Cc: linux-mips@linux-mips.org
Cc: kernel-janitors@vger.kernel.org
Cc:  # 3.10+
Signed-off-by: James Hogan

KVM: introduce kvm_arch_vcpu_async_ioctl

2017-12-14T08:26:59+00:00

After the vcpu_load/vcpu_put pushdown, the handling of asynchronous VCPU
ioctl is already much clearer in that it is obvious that they bypass
vcpu_load and vcpu_put.

However, it is still not perfect in that the different state of the VCPU
mutex is still hidden in the caller.  Separate those ioctls into a new
function kvm_arch_vcpu_async_ioctl that returns -ENOIOCTLCMD for more
"traditional" synchronous ioctls.

Cc: James Hogan 
Cc: Paul Mackerras 
Cc: Christian Borntraeger 
Reviewed-by: Christoffer Dall 
Reviewed-by: Cornelia Huck 
Suggested-by: Cornelia Huck 
Signed-off-by: Paolo Bonzini

KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl

2017-12-14T08:26:58+00:00

Move the calls to vcpu_load() and vcpu_put() in to the architecture
specific implementations of kvm_arch_vcpu_ioctl() which dispatches
further architecture-specific ioctls on to other functions.

Some architectures support asynchronous vcpu ioctls which cannot call
vcpu_load() or take the vcpu->mutex, because that would prevent
concurrent execution with a running VCPU, which is the intended purpose
of these ioctls, for example because they inject interrupts.

We repeat the separate checks for these specifics in the architecture
code for MIPS, S390 and PPC, and avoid taking the vcpu->mutex and
calling vcpu_load for these ioctls.

Signed-off-by: Christoffer Dall 
Signed-off-by: Paolo Bonzini