Commit Graph

983227 Commits

Author SHA1 Message Date
Paolo Bonzini
bcd22e145b selftests: kvm: avoid uninitialized variable warning
The variable in practice will never be uninitialized, because the
loop will always go through at least one iteration.

In case it would not, make vcpu_get_cpuid report an assertion
failure.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-15 11:42:45 -05:00
Ignacio Alvarado
1838b06bf0 selftests: kvm: add hardware_disable test
This test launches 512 VMs in serial and kills them after a random
amount of time.

The test was original written to exercise KVM user notifiers in
the context of1650b4ebc99d:
- KVM: Disable irq while unregistering user notifier
- https://lore.kernel.org/kvm/CACXrx53vkO=HKfwWwk+fVpvxcNjPrYmtDZ10qWxFvVX_PTGp3g@mail.gmail.com/

Recently, this test piqued my interest because it proved useful to
for AMD SNP in exercising the "in-use" pages, described in APM section
15.36.12, "Running SNP-Active Virtual Machines".

Signed-off-by: Ignacio Alvarado <ikalvarado@google.com>
Signed-off-by: Marc Orr <marcorr@google.com>
Message-Id: <20210213001452.1719001-1-marcorr@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-15 11:42:36 -05:00
Paolo Bonzini
8c6e67bec3 KVM/arm64 updates for Linux 5.12
- Make the nVHE EL2 object relocatable, resulting in much more
   maintainable code
 - Handle concurrent translation faults hitting the same page
   in a more elegant way
 - Support for the standard TRNG hypervisor call
 - A bunch of small PMU/Debug fixes
 - Allow the disabling of symbol export from assembly code
 - Simplification of the early init hypercall handling
 -----BEGIN PGP SIGNATURE-----
 
 iQJDBAABCgAtFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAmAmjqEPHG1hekBrZXJu
 ZWwub3JnAAoJECPQ0LrRPXpDoUEQAIrJ7YF4v4gz06a0HG9+b6fbmykHyxlG7jfm
 trvctfaiKzOybKoY5odPpNFzhbYOOdXXqYipyTHGwBYtGSy9G/9SjMKSUrfln2Ni
 lr1wBqapr9TE+SVKoR8pWWuZxGGbHVa7brNuMbMsMi1wwAsM2/n70H9PXrdq3QiK
 Ge1DWLso2oEfhtTwqNKa4dwB2MHjBhBFhhq+Nq5pslm6mmxJaYqz7pyBmw/C+2cc
 oU/6kpAa1yPAauptWXtYXJYOMHihxgEa1IdK3Gl0hUyFyu96xVkwH/KFsj+bRs23
 QGGCSdy4313hzaoGaSOTK22R98Aeg0wI9a6tcCBvVVjTAztnlu1FPtUZr8e/F7uc
 +r8xVJUJFiywt3Zktf/D7YDK9LuMMqFnj0BkI4U9nIBY59XZRNhENsBCmjru5lnL
 iXa5cuta03H4emfssIChLpgn0XHFas6t5dFXBPGbXyw0qsQchTw98iQX9LVxefUK
 rOUGPIN4nE9ESRIZe0SPlAVeCtNP8cLH7+0YG9MJ1QeDVYaUsnvy9Ln/ox+514mR
 5y2KJ6y7xnLB136SKCzPDDloYtz7BDiJq6a/RPiXKGheKoxy+N+BSe58yWCqFZYE
 Fx/cGUr7oSg39U7gCboog6BDp5e2CXBfbRllg6P47bZFfdPNwzNEzHvk49VltMxx
 Rl2W05bk
 =6EwV
 -----END PGP SIGNATURE-----

Merge tag 'kvmarm-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 updates for Linux 5.12

- Make the nVHE EL2 object relocatable, resulting in much more
  maintainable code
- Handle concurrent translation faults hitting the same page
  in a more elegant way
- Support for the standard TRNG hypervisor call
- A bunch of small PMU/Debug fixes
- Allow the disabling of symbol export from assembly code
- Simplification of the early init hypercall handling
2021-02-12 11:23:44 -05:00
Marc Zyngier
c93199e93e Merge branch 'kvm-arm64/pmu-debug-fixes-5.11' into kvmarm-master/next
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-02-12 14:08:41 +00:00
Marc Zyngier
8cb68a9d14 Merge branch 'kvm-arm64/rng-5.12' into kvmarm-master/next
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-02-12 14:08:25 +00:00
Marc Zyngier
e7ae2ecdc8 Merge branch 'kvm-arm64/hyp-reloc' into kvmarm-master/next
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-02-12 14:08:18 +00:00
Marc Zyngier
c5db649f3d Merge branch 'kvm-arm64/concurrent-translation-fault' into kvmarm-master/next
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-02-12 14:08:13 +00:00
Marc Zyngier
6b76d624e6 Merge branch 'kvm-arm64/misc-5.12' into kvmarm-master/next
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-02-12 14:08:07 +00:00
Marc Zyngier
5e6b211136 KVM/arm64 fixes for 5.11, take #2
- Don't allow tagged pointers to point to memslots
 - Filter out ARMv8.1+ PMU events on v8.0 hardware
 - Hide PMU registers from userspace when no PMU is configured
 - More PMU cleanups
 - Don't try to handle broken PSCI firmware
 - More sys_reg() to reg_to_encoding() conversions
 -----BEGIN PGP SIGNATURE-----
 
 iQJDBAABCgAtFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAmAJn00PHG1hekBrZXJu
 ZWwub3JnAAoJECPQ0LrRPXpD47AQAJtT2NbvumRBhnNAMD6+bDB0AeFdcd4s12FN
 fffsR+7UgCU4YrbMCcBEd/3gGc0/bSPQqo6ZVNaxL4M+bDR7loCKIF/kDLjv6gtu
 28Q5c+DqFirKyIWMmNSJmHPu5rXEJQOjrLtxsXigRi9QvFIALyXKYq5Bu/67Xcat
 2aoIfQyPuJYYpd/HAEa25kmJgH9Z1Wj3gQ82mGAlRWyIuSkVI0/HRGNE+dKe3fjx
 1D9lQaBwT8lsCelv6GpNZbsXo2Zh5Y/Zi7KLY6uNAD9iTHbaOwiLZMBWi9ag97Hc
 WNM4bTzWa7NGGBXvlxnoXH+o5X473JQbj/pVR8EBZvntCzdi7P8PIXo6eOIT4Z9L
 nVKXjt4NH5VER4p48tPR+ZlGYocLb7BDRFW05myUIFu0nT93O8cKmFxyuXdkJv5p
 J6DRTOohRkXh8wl7F+bBlgC+qbRbungpFWFhfpf09aKUbpR1Py+W+yrX6HDL92bT
 gGT0wKq6yTPYdHTBFQJEfSibCXPM9d2Q2cYZcLeJaMz3eZ2cxEcRU/De63qQ7EIy
 A2DXAVJnvmmzbeuCW4j7kaYAV81nKypdfBUNvZx4of/UBJSapifxAOWU9UAHPp3A
 0/qWLp2up1GOjIepF6tNpfwiPV3RvqCXi7XVy+bBIV+pgfHvl3DkBGcVhLKXI2JE
 JO9jh9rn
 =GHVB
 -----END PGP SIGNATURE-----

Merge tag 'kvmarm-fixes-5.11-2' into kvmarm-master/next

KVM/arm64 fixes for 5.11, take #2

- Don't allow tagged pointers to point to memslots
- Filter out ARMv8.1+ PMU events on v8.0 hardware
- Hide PMU registers from userspace when no PMU is configured
- More PMU cleanups
- Don't try to handle broken PSCI firmware
- More sys_reg() to reg_to_encoding() conversions

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-02-12 14:07:39 +00:00
Sean Christopherson
7137b7ae6f KVM: x86/xen: Explicitly pad struct compat_vcpu_info to 64 bytes
Add a 2 byte pad to struct compat_vcpu_info so that the sum size of its
fields is actually 64 bytes.  The effective size without the padding is
also 64 bytes due to the compiler aligning evtchn_pending_sel to a 4-byte
boundary, but depending on compiler alignment is subtle and unnecessary.

Opportunistically replace spaces with tables in the other fields.

Cc: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210210182609.435200-6-seanjc@google.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-11 08:03:02 -05:00
Sean Christopherson
f1b83973a1 KVM: selftests: Don't bother mapping GVA for Xen shinfo test
Don't bother mapping the Xen shinfo pages into the guest, they don't need
to be accessed using the GVAs and passing a define with "GPA" in the name
to addr_gva2hpa() is confusing.

Cc: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210210182609.435200-5-seanjc@google.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-11 08:02:49 -05:00
Sean Christopherson
fc79ef3e7b KVM: selftests: Fix hex vs. decimal snafu in Xen test
The Xen shinfo selftest uses '40' when setting the GPA of the vCPU info
struct, but checks for the result at '0x40'.  Arbitrarily use the hex
version to resolve the bug.

Fixes: 8d4e7e8083 ("KVM: x86: declare Xen HVM shared info capability and add test case")
Cc: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210210182609.435200-4-seanjc@google.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-11 08:02:09 -05:00
Sean Christopherson
a685d99208 KVM: selftests: Fix size of memslots created by Xen tests
For better or worse, the memslot APIs take the number of pages, not the
size in bytes.  The Xen tests need 2 pages, not 8192 pages.

Fixes: 8d4e7e8083 ("KVM: x86: declare Xen HVM shared info capability and add test case")
Cc: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210210182609.435200-3-seanjc@google.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-11 08:02:09 -05:00
Sean Christopherson
2f3b90fd90 KVM: selftests: Ignore recently added Xen tests' build output
Add the new Xen test binaries to KVM selftest's .gitnore.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210210182609.435200-2-seanjc@google.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-11 08:02:09 -05:00
Peter Shier
346b59f220 KVM: selftests: Add missing header file needed by xAPIC IPI tests
Fixes: 678e90a349 ("KVM: selftests: Test IPI to halted vCPU in xAPIC while backing page moves")
Cc: Andrew Jones <drjones@redhat.com>
Cc: Jim Mattson <jmattson@google.com>
Signed-off-by: Peter Shier <pshier@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210210011747.240913-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-11 08:02:08 -05:00
Ricardo Koller
47bc726fe8 KVM: selftests: Add operand to vmsave/vmload/vmrun in svm.c
Building the KVM selftests with LLVM's integrated assembler fails with:

  $ CFLAGS=-fintegrated-as make -C tools/testing/selftests/kvm CC=clang
  lib/x86_64/svm.c:77:16: error: too few operands for instruction
          asm volatile ("vmsave\n\t" : : "a" (vmcb_gpa) : "memory");
                        ^
  <inline asm>:1:2: note: instantiated into assembly here
          vmsave
          ^
  lib/x86_64/svm.c:134:3: error: too few operands for instruction
                  "vmload\n\t"
                  ^
  <inline asm>:1:2: note: instantiated into assembly here
          vmload
          ^
This is because LLVM IAS does not currently support calling vmsave,
vmload, or vmload without an explicit %rax operand.

Add an explicit operand to vmsave, vmload, and vmrum in svm.c. Fixing
this was suggested by Sean Christopherson.

Tested: building without this error in clang 11. The following patch
(not queued yet) needs to be applied to solve the other remaining error:
"selftests: kvm: remove reassignment of non-absolute variables".

Suggested-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/kvm/X+Df2oQczVBmwEzi@google.com/
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Ricardo Koller <ricarkol@google.com>
Message-Id: <20210210031719.769837-1-ricarkol@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-11 08:02:08 -05:00
Wei Yongjun
2e215216d6 KVM: SVM: Make symbol 'svm_gp_erratum_intercept' static
The sparse tool complains as follows:

arch/x86/kvm/svm/svm.c:204:6: warning:
 symbol 'svm_gp_erratum_intercept' was not declared. Should it be static?

This symbol is not used outside of svm.c, so this
commit marks it static.

Fixes: 82a11e9c6f ("KVM: SVM: Add emulation support for #GP triggered by SVM instructions")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Message-Id: <20210210075958.1096317-1-weiyongjun1@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-11 08:02:08 -05:00
Paolo Bonzini
67ccd52766 PPC KVM update for 5.12
- Support for second data watchpoint on POWER10, from Ravi Bangoria
 - Remove some complex workarounds for buggy early versions of POWER9
 - Guest entry/exit fixes from Nick Piggin and Fabiano Rosas
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQEcBAABCAAGBQJgJNeuAAoJEJ2a6ncsY3GfDXMH/1eJRM5K8FGKe9Xy13Z9sUT+
 b2XUSeiYE0zPPWwEuIY+GrT2DvijPqEfM3MYJEh5ktjg3Sf5fYcfuvgUpBieVKlq
 WkeB/10f5KfA7uFhT/E4kryiF7hJxA9AtxBiZkON4tlMfbskTc9Eg1ojxuYnaYm+
 u2NPGb8v0Oe2DMAzKePVsciV2ayIo0Gxij1nB4Yqc/dYqT+Yli0iQVeGb9w8XlgC
 LFKRk+9VluJglhMO/F7izTG2D2PJGmmKuU0V+QyQ0MNte4HgJwIjfivslKu+vCJd
 esHGqq0scaVqJnI3YYJ9vAszhlPZTNccGCY1F8EQgGGE8MR8qCxzpIZF1IlHxRw=
 =qIO+
 -----END PGP SIGNATURE-----

Merge tag 'kvm-ppc-next-5.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD

PPC KVM update for 5.12

- Support for second data watchpoint on POWER10, from Ravi Bangoria
- Remove some complex workarounds for buggy early versions of POWER9
- Guest entry/exit fixes from Nick Piggin and Fabiano Rosas
2021-02-11 08:00:04 -05:00
Waiman Long
d8d0da4eee locking/arch: Move qrwlock.h include after qspinlock.h
include/asm-generic/qrwlock.h was trying to get arch_spin_is_locked via
asm-generic/qspinlock.h.  However, this does not work because architectures
might be using queued rwlocks but not queued spinlocks (csky), or because they
might be defining their own queued_* macros before including asm/qspinlock.h.

To fix this, ensure that asm/spinlock.h always includes qrwlock.h after
defining arch_spin_is_locked (either directly for csky, or via
asm/qspinlock.h for other architectures).  The only inclusion elsewhere
is in kernel/locking/qrwlock.c.  That one is really unnecessary because
the file is only compiled in SMP configurations (config QUEUED_RWLOCKS
depends on SMP) and in that case linux/spinlock.h already includes
asm/qrwlock.h if needed, via asm/spinlock.h.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Waiman Long <longman@redhat.com>
Fixes: 26128cb6c7 ("locking/rwlocks: Add contention detection for rwlocks")
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Ben Gardon <bgardon@google.com>
[Add arch/sparc and kernel/locking parts per discussion with Waiman. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-11 07:59:54 -05:00
Nicholas Piggin
72476aaa46 KVM: PPC: Book3S HV: Fix host radix SLB optimisation with hash guests
Commit 68ad28a4cd ("KVM: PPC: Book3S HV: Fix radix guest SLB side
channel") incorrectly removed the radix host instruction patch to skip
re-loading the host SLB entries when exiting from a hash
guest. Restore it.

Fixes: 68ad28a4cd ("KVM: PPC: Book3S HV: Fix radix guest SLB side channel")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-11 17:28:15 +11:00
Paul Mackerras
ab950e1acd KVM: PPC: Book3S HV: Ensure radix guest has no SLB entries
Commit 68ad28a4cd ("KVM: PPC: Book3S HV: Fix radix guest SLB side
channel") changed the older guest entry path, with the side effect
that vcpu->arch.slb_max no longer gets cleared for a radix guest.
This means that a HPT guest which loads some SLB entries, switches to
radix mode, runs the guest using the old guest entry path (e.g.,
because the indep_threads_mode module parameter has been set to
false), and then switches back to HPT mode would now see the old SLB
entries being present, whereas previously it would have seen no SLB
entries.

To avoid changing guest-visible behaviour, this adds a store
instruction to clear vcpu->arch.slb_max for a radix guest using the
old guest entry path.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-11 17:19:42 +11:00
Fabiano Rosas
a722076e94 KVM: PPC: Don't always report hash MMU capability for P9 < DD2.2
These machines don't support running both MMU types at the same time,
so remove the KVM_CAP_PPC_MMU_HASH_V3 capability when the host is
using Radix MMU.

[paulus@ozlabs.org - added defensive check on
 kvmppc_hv_ops->hash_v3_possible]

Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-10 16:19:36 +11:00
Fabiano Rosas
25edcc50d7 KVM: PPC: Book3S HV: Save and restore FSCR in the P9 path
The Facility Status and Control Register is a privileged SPR that
defines the availability of some features in problem state. Since it
can be written by the guest, we must restore it to the previous host
value after guest exit.

This restoration is currently done by taking the value from
current->thread.fscr, which in the P9 path is not enough anymore
because the guest could context switch the QEMU thread, causing the
guest-current value to be saved into the thread struct.

The above situation manifested when running a QEMU linked against a
libc with System Call Vectored support, which causes scv
instructions to be run by QEMU early during the guest boot (during
SLOF), at which point the FSCR is 0 due to guest entry. After a few
scv calls (1 to a couple hundred), the context switching happens and
the QEMU thread runs with the guest value, resulting in a Facility
Unavailable interrupt.

This patch saves and restores the host value of FSCR in the inner
guest entry loop in a way independent of current->thread.fscr. The old
way of doing it is still kept in place because it works for the old
entry path.

Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-10 14:31:08 +11:00
Yang Li
63e9f23573 KVM: PPC: remove unneeded semicolon
Eliminate the following coccicheck warning:
./arch/powerpc/kvm/booke.c:701:2-3: Unneeded semicolon

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-10 14:31:08 +11:00
Nicholas Piggin
7a7f94a3a9 KVM: PPC: Book3S HV: Use POWER9 SLBIA IH=6 variant to clear SLB
IH=6 may preserve hypervisor real-mode ERAT entries and is the
recommended SLBIA hint for switching partitions.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-10 14:31:08 +11:00
Nicholas Piggin
078ebe35fc KVM: PPC: Book3S HV: No need to clear radix host SLB before loading HPT guest
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-10 14:31:08 +11:00
Nicholas Piggin
68ad28a4cd KVM: PPC: Book3S HV: Fix radix guest SLB side channel
The slbmte instruction is legal in radix mode, including radix guest
mode. This means radix guests can load the SLB with arbitrary data.

KVM host does not clear the SLB when exiting a guest if it was a
radix guest, which would allow a rogue radix guest to use the SLB as
a side channel to communicate with other guests.

Fix this by ensuring the SLB is cleared when coming out of a radix
guest. Only the first 4 entries are a concern, because radix guests
always run with LPCR[UPRT]=1, which limits the reach of slbmte. slbia
is not used (except in a non-performance-critical path) because it
can clear cached translations.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-10 14:31:08 +11:00
Nicholas Piggin
b1b1697ae0 KVM: PPC: Book3S HV: Remove support for running HPT guest on RPT host without mixed mode support
This reverts much of commit c01015091a ("KVM: PPC: Book3S HV: Run HPT
guests on POWER9 radix hosts"), which was required to run HPT guests on
RPT hosts on early POWER9 CPUs without support for "mixed mode", which
meant the host could not run with MMU on while guests were running.

This code has some corner case bugs, e.g., when the guest hits a machine
check or HMI the primary locks up waiting for secondaries to switch LPCR
to host, which they never do. This could all be fixed in software, but
most CPUs in production have mixed mode support, and those that don't
are believed to be all in installations that don't use this capability.
So simplify things and remove support.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Tested-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-10 14:31:08 +11:00
Ravi Bangoria
d9a47edabc KVM: PPC: Book3S HV: Introduce new capability for 2nd DAWR
Introduce KVM_CAP_PPC_DAWR1 which can be used by QEMU to query whether
KVM supports 2nd DAWR or not. The capability is by default disabled
even when the underlying CPU supports 2nd DAWR. QEMU needs to check
and enable it manually to use the feature.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-10 14:31:08 +11:00
Ravi Bangoria
bd1de1a0e6 KVM: PPC: Book3S HV: Add infrastructure to support 2nd DAWR
KVM code assumes single DAWR everywhere. Add code to support 2nd DAWR.
DAWR is a hypervisor resource and thus H_SET_MODE hcall is used to set/
unset it. Introduce new case H_SET_MODE_RESOURCE_SET_DAWR1 for 2nd DAWR.
Also, KVM will support 2nd DAWR only if CPU_FTR_DAWR1 is set.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-10 14:31:08 +11:00
Ravi Bangoria
122954ed7d KVM: PPC: Book3S HV: Rename current DAWR macros and variables
Power10 is introducing a second DAWR (Data Address Watchpoint
Register). Use real register names (with suffix 0) from ISA for
current macros and variables used by kvm.  One exception is
KVM_REG_PPC_DAWR.  Keep it as it is because it's uapi so changing it
will break userspace.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-10 14:31:08 +11:00
Ravi Bangoria
afe7504930 KVM: PPC: Book3S HV: Allow nested guest creation when L0 hv_guest_state > L1
On powerpc, L1 hypervisor takes help of L0 using H_ENTER_NESTED
hcall to load L2 guest state in cpu. L1 hypervisor prepares the
L2 state in struct hv_guest_state and passes a pointer to it via
hcall. Using that pointer, L0 reads/writes that state directly
from/to L1 memory. Thus L0 must be aware of hv_guest_state layout
of L1. Currently it uses version field to achieve this. i.e. If
L0 hv_guest_state.version != L1 hv_guest_state.version, L0 won't
allow nested kvm guest.

This restriction can be loosened up a bit. L0 can be taught to
understand older layout of hv_guest_state, if we restrict the
new members to be added only at the end, i.e. we can allow
nested guest even when L0 hv_guest_state.version > L1
hv_guest_state.version. Though, the other way around is not
possible.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2021-02-10 14:31:08 +11:00
Paolo Bonzini
9294b8a125 Documentation: kvm: fix warning
Documentation/virt/kvm/api.rst:4927: WARNING: Title underline too short.

4.130 KVM_XEN_VCPU_GET_ATTR
--------------------------

Fixes: e1f68169a4 ("KVM: Add documentation for Xen hypercall and shared_info updates")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:42:10 -05:00
David Woodhouse
0c165b3c01 KVM: x86/xen: Allow reset of Xen attributes
In order to support Xen SHUTDOWN_soft_reset (for guest kexec, etc.) the
VMM needs to be able to tear everything down and return the Xen features
to a clean slate.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20210208232326.1830370-1-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:42:10 -05:00
Maciej S. Szmigiero
8f5c44f953 KVM: x86/mmu: Make HVA handler retpoline-friendly
When retpolines are enabled they have high overhead in the inner loop
inside kvm_handle_hva_range() that iterates over the provided memory area.

Let's mark this function and its TDP MMU equivalent __always_inline so
compiler will be able to change the call to the actual handler function
inside each of them into a direct one.

This significantly improves performance on the unmap test on the existing
kernel memslot code (tested on a Xeon 8167M machine):
30 slots in use:
Test       Before   After     Improvement
Unmap      0.0353s  0.0334s   5%
Unmap 2M   0.00104s 0.000407s 61%

509 slots in use:
Test       Before   After     Improvement
Unmap      0.0742s  0.0740s   None
Unmap 2M   0.00221s 0.00159s  28%

Looks like having an indirect call in these functions (and, so, a
retpoline) might have interfered with unrolling of the whole loop in the
CPU.

Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Message-Id: <732d3fe9eb68aa08402a638ab0309199fa89ae56.1612810129.git.maciej.szmigiero@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:42:09 -05:00
Vitaly Kuznetsov
b9ce0f86d9 KVM: x86: hyper-v: Drop hv_vcpu_to_vcpu() helper
hv_vcpu_to_vcpu() helper is only used by other helpers and
is not very complex, we can drop it without much regret.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-16-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:42:09 -05:00
Vitaly Kuznetsov
fc08b628d7 KVM: x86: hyper-v: Allocate Hyper-V context lazily
Hyper-V context is only needed for guests which use Hyper-V emulation in
KVM (e.g. Windows/Hyper-V guests) so we don't actually need to allocate
it in kvm_arch_vcpu_create(), we can postpone the action until Hyper-V
specific MSRs are accessed or SynIC is enabled.

Once allocated, let's keep the context alive for the lifetime of the vCPU
as an attempt to free it would require additional synchronization with
other vCPUs and normally it is not supposed to happen.

Note, Hyper-V style hypercall enablement is done by writing to
HV_X64_MSR_GUEST_OS_ID so we don't need to worry about allocating Hyper-V
context from kvm_hv_hypercall().

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-15-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:40:50 -05:00
Vitaly Kuznetsov
8f014550df KVM: x86: hyper-v: Make Hyper-V emulation enablement conditional
Hyper-V emulation is enabled in KVM unconditionally. This is bad at least
from security standpoint as it is an extra attack surface. Ideally, there
should be a per-VM capability explicitly enabled by VMM but currently it
is not the case and we can't mandate one without breaking backwards
compatibility. We can, however, check guest visible CPUIDs and only enable
Hyper-V emulation when "Hv#1" interface was exposed in
HYPERV_CPUID_INTERFACE.

Note, VMMs are free to act in any sequence they like, e.g. they can try
to set MSRs first and CPUIDs later so we still need to allow the host
to read/write Hyper-V specific MSRs unconditionally.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-14-vkuznets@redhat.com>
[Add selftest vcpu_set_hv_cpuid API to avoid breaking xen_vmcall_test. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:39:56 -05:00
Vitaly Kuznetsov
4592b7eaa8 KVM: x86: hyper-v: Allocate 'struct kvm_vcpu_hv' dynamically
Hyper-V context is only needed for guests which use Hyper-V emulation in
KVM (e.g. Windows/Hyper-V guests). 'struct kvm_vcpu_hv' is, however, quite
big, it accounts for more than 1/4 of the total 'struct kvm_vcpu_arch'
which is also quite big already. This all looks like a waste.

Allocate 'struct kvm_vcpu_hv' dynamically. This patch does not bring any
(intentional) functional change as we still allocate the context
unconditionally but it paves the way to doing that only when needed.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-13-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:17:15 -05:00
Vitaly Kuznetsov
f2bc14b69c KVM: x86: hyper-v: Prepare to meet unallocated Hyper-V context
Currently, Hyper-V context is part of 'struct kvm_vcpu_arch' and is always
available. As a preparation to allocating it dynamically, check that it is
not NULL at call sites which can normally proceed without it i.e. the
behavior is identical to the situation when Hyper-V emulation is not being
used by the guest.

When Hyper-V context for a particular vCPU is not allocated, we may still
need to get 'vp_index' from there. E.g. in a hypothetical situation when
Hyper-V emulation was enabled on one CPU and wasn't on another, Hyper-V
style send-IPI hypercall may still be used. Luckily, vp_index is always
initialized to kvm_vcpu_get_idx() and can only be changed when Hyper-V
context is present. Introduce kvm_hv_get_vpindex() helper for
simplification.

No functional change intended.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-12-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:17:14 -05:00
Vitaly Kuznetsov
9ff5e0304e KVM: x86: hyper-v: Always use to_hv_vcpu() accessor to get to 'struct kvm_vcpu_hv'
As a preparation to allocating Hyper-V context dynamically, make it clear
who's the user of the said context.

No functional change intended.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-11-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:17:13 -05:00
Vitaly Kuznetsov
72167a9d7d KVM: x86: hyper-v: Stop shadowing global 'current_vcpu' variable
'current_vcpu' variable in KVM is a per-cpu pointer to the currently
scheduled vcpu. kvm_hv_flush_tlb()/kvm_hv_send_ipi() functions used
to have local 'vcpu' variable to iterate over vCPUs but it's gone
now and there's no need to use anything but the standard 'vcpu' as
an argument.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-10-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:17:13 -05:00
Vitaly Kuznetsov
05f04ae4ff KVM: x86: hyper-v: Introduce to_kvm_hv() helper
Spelling '&kvm->arch.hyperv' correctly is hard. Also, this makes the code
more consistent with vmx/svm where to_kvm_vmx()/to_kvm_svm() are already
being used.

Opportunistically change kvm_hv_msr_{get,set}_crash_{data,ctl}() and
kvm_hv_msr_set_crash_data() to take 'kvm' instead of 'vcpu' as these
MSRs are partition wide.

No functional change intended.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-9-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:17:12 -05:00
Vitaly Kuznetsov
f69b55efef KVM: x86: hyper-v: Rename vcpu_to_hv_syndbg() to to_hv_syndbg()
vcpu_to_hv_syndbg()'s argument is  always 'vcpu' so there's no need to have
an additional prefix. Also, this makes the code more consistent with
vmx/svm where to_vmx()/to_svm() are being used.

No functional change intended.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-8-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:17:12 -05:00
Vitaly Kuznetsov
aafa97fd1c KVM: x86: hyper-v: Rename vcpu_to_stimer()/stimer_to_vcpu()
vcpu_to_stimers()'s argument is almost always 'vcpu' so there's no need to
have an additional prefix. Also, this makes the naming more consistent with
to_hv_vcpu()/to_hv_synic().

Rename stimer_to_vcpu() to hv_stimer_to_vcpu() for consitency.

No functional change intended.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-7-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:17:11 -05:00
Vitaly Kuznetsov
e0121fa29a KVM: x86: hyper-v: Rename vcpu_to_synic()/synic_to_vcpu()
vcpu_to_synic()'s argument is almost always 'vcpu' so there's no need to
have an additional prefix. Also, as this is used outside of hyper-v
emulation code, add '_hv_' part to make it clear what this s. This makes
the naming more consistent with to_hv_vcpu().

Rename synic_to_vcpu() to hv_synic_to_vcpu() for consistency.

No functional change intended.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-6-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:17:11 -05:00
Vitaly Kuznetsov
ef3f3980de KVM: x86: hyper-v: Rename vcpu_to_hv_vcpu() to to_hv_vcpu()
vcpu_to_hv_vcpu()'s argument is almost always 'vcpu' so there's
no need to have an additional prefix. Also, this makes the code
more consistent with vmx/svm where to_vmx()/to_svm() are being
used.

No functional change intended.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-5-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:17:10 -05:00
Vitaly Kuznetsov
cb5b916172 KVM: x86: hyper-v: Drop unused kvm_hv_vapic_assist_page_enabled()
kvm_hv_vapic_assist_page_enabled() seems to be unused since its
introduction in commit 10388a0716 ("KVM: Add HYPER-V apic access MSRs"),
drop it.

Reported-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-4-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:17:10 -05:00
Vitaly Kuznetsov
a75b40a4dd selftests: kvm: Properly set Hyper-V CPUIDs in evmcs_test
Generally, when Hyper-V emulation is enabled, VMM is supposed to set
Hyper-V CPUID identifications so the guest knows that Hyper-V features
are available. evmcs_test doesn't currently do that but so far Hyper-V
emulation in KVM was enabled unconditionally. As we are about to change
that, proper Hyper-V CPUID identification should be set in selftests as
well.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-3-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:17:10 -05:00
Vitaly Kuznetsov
32f00fd9ef selftests: kvm: Move kvm_get_supported_hv_cpuid() to common code
kvm_get_supported_hv_cpuid() may come handy in all Hyper-V related tests.
Split it off hyperv_cpuid test, create system-wide and vcpu versions.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09 08:17:09 -05:00