Paolo Bonzini [Tue, 7 Apr 2015 16:10:03 +0000 (18:10 +0200)]
Merge tag 'kvm-s390-next-20150331' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
Features and fixes for 4.1 (kvm/next)
1. Assorted changes
1.1 allow more feature bits for the guest
1.2 Store breaking event address on program interrupts
2. Interrupt handling rework
2.1 Fix copy_to_user while holding a spinlock (cc stable)
2.2 Rework floating interrupts to follow the priorities
2.3 Allow to inject all local interrupts via new ioctl
2.4 allow to get/set the full local irq state, e.g. for migration
and introspection
Paolo Bonzini [Tue, 7 Apr 2015 16:06:01 +0000 (18:06 +0200)]
Merge tag 'kvm-arm-fixes-4.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into 'kvm-next'
Fixes for KVM/ARM for 4.0-rc5.
Fixes page refcounting issues in our Stage-2 page table management code,
fixes a missing unlock in a gicv3 error path, and fixes a race that can
cause lost interrupts if signals are pending just prior to entering the
guest.
Jens Freimann [Mon, 24 Nov 2014 16:13:46 +0000 (17:13 +0100)]
KVM: s390: migrate vcpu interrupt state
This patch adds support to migrate vcpu interrupts. Two new vcpu ioctls
are added which get/set the complete status of pending interrupts in one
go. The ioctls are marked as available with the new capability
KVM_CAP_S390_IRQ_STATE.
We can not use a ONEREG, as the number of pending local interrupts is not
constant and depends on the number of CPUs.
To retrieve the interrupt state we add an ioctl KVM_S390_GET_IRQ_STATE.
Its input parameter is a pointer to a struct kvm_s390_irq_state which
has a buffer and length. For all currently pending interrupts, we copy
a struct kvm_s390_irq into the buffer and pass it to userspace.
To store interrupt state into a buffer provided by userspace, we add an
ioctl KVM_S390_SET_IRQ_STATE. It passes a struct kvm_s390_irq_state into
the kernel and injects all interrupts contained in the buffer.
Jens Freimann [Thu, 19 Mar 2015 14:12:12 +0000 (15:12 +0100)]
KVM: s390: refactor vcpu injection function
Let's provide a version of kvm_s390_inject_vcpu() that
does not acquire the local-interrupt lock and skips
waking up the vcpu.
To be used in a later patch for vcpu-local interrupt migration,
where we are already holding the lock.
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Jens Freimann [Tue, 11 Nov 2014 19:57:06 +0000 (20:57 +0100)]
KVM: s390: add ioctl to inject local interrupts
We have introduced struct kvm_s390_irq a while ago which allows to
inject all kinds of interrupts as defined in the Principles of
Operation.
Add ioctl to inject interrupts with the extended struct kvm_s390_irq
We now have a mechanism for delivering interrupts according to their priority.
Let's inject them using our new infrastructure (instead of letting only hardware
handle them), so we can be sure that the irq priorities are satisfied.
For s390, the cpu timer and the clock comparator are to be checked for common
code kvm_cpu_has_pending_timer(), although the cpu timer is only stepped when
the guest is being executed.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
KVM: s390: deliver floating interrupts in order of priority
This patch makes interrupt handling compliant to the z/Architecture
Principles of Operation with regard to interrupt priorities.
Add a bitmap for pending floating interrupts. Each bit relates to a
interrupt type and its list. A turned on bit indicates that a list
contains items (interrupts) which need to be delivered. When delivering
interrupts on a cpu we can merge the existing bitmap for cpu-local
interrupts and floating interrupts and have a single mechanism for
delivery.
Currently we have one list for all kinds of floating interrupts and a
corresponding spin lock. This patch adds a separate list per
interrupt type. An exception to this are service signal and machine check
interrupts, as there can be only one pending interrupt at a time.
Jens Freimann [Mon, 16 Mar 2015 11:17:13 +0000 (12:17 +0100)]
KVM: s390: fix get_all_floating_irqs
This fixes a bug introduced with commit c05c4186bbe4 ("KVM: s390:
add floating irq controller").
get_all_floating_irqs() does copy_to_user() while holding
a spin lock. Let's fix this by filling a temporary buffer
first and copy it to userspace after giving up the lock.
Cc: <stable@vger.kernel.org> # 3.18+: 69a8d4562638 KVM: s390: no need to hold... Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
KVM: s390: enable more features that need no hypervisor changes
After some review about what these facilities do, the following
facilities will work under KVM and can, therefore, be reported
to the guest if the cpu model and the host cpu provide this bit.
There are plans underway to make the whole bit thing more readable,
but its not yet finished. So here are some last bit changes and
we enhance the KVM mask with:
9 The sense-running-status facility is installed in the
z/Architecture architectural mode.
---> handled by SIE or KVM
10 The conditional-SSKE facility is installed in the
z/Architecture architectural mode.
---> handled by SIE. KVM will retry SIE
13 The IPTE-range facility is installed in the
z/Architecture architectural mode.
---> handled by SIE. KVM will retry SIE
36 The enhanced-monitor facility is installed in the
z/Architecture architectural mode.
---> handled by SIE
47 The CMPSC-enhancement facility is installed in the
z/Architecture architectural mode.
---> handled by SIE
48 The decimal-floating-point zoned-conversion facility
is installed in the z/Architecture architectural mode.
---> handled by SIE
49 The execution-hint, load-and-trap, miscellaneous-
instruction-extensions and processor-assist
---> handled by SIE
51 The local-TLB-clearing facility is installed in the
z/Architecture architectural mode.
---> handled by SIE
52 The interlocked-access facility 2 is installed.
---> handled by SIE
53 The load/store-on-condition facility 2 and load-and-
zero-rightmost-byte facility are installed in the
z/Architecture architectural mode.
---> handled by SIE
57 The message-security-assist-extension-5 facility is
installed in the z/Architecture architectural mode.
---> handled by SIE
66 The reset-reference-bits-multiple facility is installed
in the z/Architecture architectural mode.
---> handled by SIE. KVM will retry SIE
80 The decimal-floating-point packed-conversion
facility is installed in the z/Architecture architectural
mode.
---> handled by SIE
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Tested-by: Michael Mueller <mimu@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
KVM: s390: store the breaking-event address on pgm interrupts
If the PER-3 facility is installed, the breaking-event address is to be
stored in the low core.
There is no facility bit for PER-3 in stfl(e) and Linux always uses the
value at address 272 no matter if PER-3 is available or not.
We can't hide its existence from the guest. All program interrupts
injected via the SIE automatically store this information if the PER-3
facility is available in the hypervisor. Also the itdb contains the
address automatically.
As there is no switch to turn this mechanism off, let's simply make it
consistent and also store the breaking event address in case of manual
program interrupt injection.
Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Nikolay Nikolaev [Sat, 24 Jan 2015 12:00:02 +0000 (12:00 +0000)]
KVM: arm/arm64: enable KVM_CAP_IOEVENTFD
As the infrastructure for eventfd has now been merged, report the
ioeventfd capability as being supported.
Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
[maz: grouped the case entry with the others, fixed commit log] Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Andre Przywara [Sat, 28 Mar 2015 01:13:13 +0000 (01:13 +0000)]
KVM: arm/arm64: rework MMIO abort handling to use KVM MMIO bus
Currently we have struct kvm_exit_mmio for encapsulating MMIO abort
data to be passed on from syndrome decoding all the way down to the
VGIC register handlers. Now as we switch the MMIO handling to be
routed through the KVM MMIO bus, it does not make sense anymore to
use that structure already from the beginning. So we keep the data in
local variables until we put them into the kvm_io_bus framework.
Then we fill kvm_exit_mmio in the VGIC only, making it a VGIC private
structure. On that way we replace the data buffer in that structure
with a pointer pointing to a single location in a local variable, so
we get rid of some copying on the way.
With all of the virtual GIC emulation code now being registered with
the kvm_io_bus, we can remove all of the old MMIO handling code and
its dispatching functionality.
I didn't bother to rename kvm_exit_mmio (to vgic_mmio or something),
because that touches a lot of code lines without any good reason.
This is based on an original patch by Nikolay.
Signed-off-by: Andre Przywara <andre.przywara@arm.com> Cc: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Andre Przywara [Thu, 26 Mar 2015 14:39:37 +0000 (14:39 +0000)]
KVM: arm/arm64: prepare GICv3 emulation to use kvm_io_bus MMIO handling
Using the framework provided by the recent vgic.c changes, we
register a kvm_io_bus device on mapping the virtual GICv3 resources.
The distributor mapping is pretty straight forward, but the
redistributors need some more love, since they need to be tagged with
the respective redistributor (read: VCPU) they are connected with.
We use the kvm_io_bus framework to register one devices per VCPU.
Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Andre Przywara [Thu, 26 Mar 2015 14:39:36 +0000 (14:39 +0000)]
KVM: arm/arm64: merge GICv3 RD_base and SGI_base register frames
Currently we handle the redistributor registers in two separate MMIO
regions, one for the overall behaviour and SPIs and one for the
SGIs/PPIs. That latter forces the creation of _two_ KVM I/O bus
devices for each redistributor.
Since the spec mandates those two pages to be contigious, we could as
well merge them and save the churn with the second KVM I/O bus device.
Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427635984-8113-3-git-send-email-namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The eflags are redefined (using other defines) in emulate.c.
Use the definition from processor-flags.h as some mess already started.
No functional change.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427635984-8113-2-git-send-email-namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Nadav Amit [Mon, 30 Mar 2015 12:39:21 +0000 (15:39 +0300)]
KVM: x86: BSF and BSR emulation change register unnecassarily
If the source of BSF and BSR is zero, the destination register should not
change. That is how real hardware behaves. If we set the destination even with
the same value that we had before, we may clear bits [63:32] unnecassarily.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427719163-5429-4-git-send-email-namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Nadav Amit [Mon, 30 Mar 2015 12:39:20 +0000 (15:39 +0300)]
KVM: x86: POPA emulation may not clear bits [63:32]
POPA should assign the values to the registers as usual registers are assigned.
In other words, 32-bits register assignments should clear bits [63:32] of the
register.
Split the code of register assignments that will be used by future changes as
well.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427719163-5429-3-git-send-email-namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Nadav Amit [Mon, 30 Mar 2015 12:39:19 +0000 (15:39 +0300)]
KVM: x86: CMOV emulation on legacy mode is wrong
On legacy mode CMOV emulation should still clear bits [63:32] even if the
assignment is not done. The previous fix 140bad89fd ("KVM: x86: emulation of
dword cmov on long-mode should clear [63:32]") was incomplete.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427719163-5429-2-git-send-email-namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Petr Matousek [Wed, 11 Mar 2015 11:16:09 +0000 (12:16 +0100)]
kvm: x86: i8259: return initialized data on invalid-size read
If data is read from PIC with invalid access size, the return data stays
uninitialized even though success is returned.
Fix this by always initializing the data.
Signed-off-by: Petr Matousek <pmatouse@redhat.com> Reported-by: Nadav Amit <nadav.amit@gmail.com>
Message-Id: <20150311111609.GG8544@dhcp-25-225.brq.redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Mon, 30 Mar 2015 14:37:06 +0000 (16:37 +0200)]
Merge tag 'kvm_mips_20150327' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/kvm-mips into kvm-next
MIPS KVM Guest FPU & SIMD (MSA) Support
Add guest FPU and MIPS SIMD Architecture (MSA) support to MIPS KVM, by
enabling the host FPU/MSA while in guest mode. This adds two new KVM
capabilities, KVM_CAP_MIPS_FPU & KVM_CAP_MIPS_MSA, and supports the 3 FP
register modes (FR=0, FR=1, FRE=1), and 128-bit MSA vector registers,
with lazy FPU/MSA context save and restore.
Some required MIPS FP/MSA fixes are merged in from a branch in the MIPS
tree first.
James Hogan [Mon, 8 Dec 2014 23:07:56 +0000 (23:07 +0000)]
MIPS: KVM: Wire up MSA capability
Now that the code is in place for KVM to support MIPS SIMD Architecutre
(MSA) in MIPS guests, wire up the new KVM_CAP_MIPS_MSA capability.
For backwards compatibility, the capability must be explicitly enabled
in order to detect or make use of MSA from the guest.
The capability is not supported if the hardware supports MSA vector
partitioning, since the extra support cannot be tested yet and it
extends the state that the userland program would have to save.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Cc: linux-api@vger.kernel.org Cc: linux-doc@vger.kernel.org
James Hogan [Tue, 2 Dec 2014 15:48:24 +0000 (15:48 +0000)]
MIPS: KVM: Expose MSA registers
Add KVM register numbers for the MIPS SIMD Architecture (MSA) registers,
and implement access to them with the KVM_GET_ONE_REG / KVM_SET_ONE_REG
ioctls when the MSA capability is enabled (exposed in a later patch) and
present in the guest according to its Config3.MSAP bit.
The MSA vector registers use the same register numbers as the FPU
registers except with a different size (128bits). Since MSA depends on
Status.FR=1, these registers are inaccessible when Status.FR=0. These
registers are returned as a single native endian 128bit value, rather
than least significant half first with each 64-bit half native endian as
the kernel uses internally.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Cc: linux-api@vger.kernel.org Cc: linux-doc@vger.kernel.org
James Hogan [Fri, 6 Feb 2015 10:56:27 +0000 (10:56 +0000)]
MIPS: KVM: Add MSA exception handling
Add guest exception handling for MIPS SIMD Architecture (MSA) floating
point exceptions and MSA disabled exceptions.
MSA floating point exceptions from the guest need passing to the guest
kernel, so for these a guest MSAFPE is emulated.
MSA disabled exceptions are normally handled by passing a reserved
instruction exception to the guest (because no guest MSA was supported),
but the hypervisor can now handle them if the guest has MSA by passing
an MSA disabled exception to the guest, or if the guest has MSA enabled
by transparently restoring the guest MSA context and enabling MSA and
the FPU.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
James Hogan [Fri, 6 Feb 2015 23:01:00 +0000 (23:01 +0000)]
MIPS: KVM: Emulate MSA bits in COP0 interface
Emulate MSA related parts of COP0 interface so that the guest will be
able to enable/disable MSA (Config5.MSAEn) once the MSA capability has
been wired up.
As with the FPU (Status.CU1) setting Config5.MSAEn has no immediate
effect if the MSA state isn't live, as MSA state is restored lazily on
first use. Changes after the MSA state has been restored take immediate
effect, so that the guest can start getting MSA disabled exceptions
right away for guest MSA operations. The MSA state is saved lazily too,
as MSA may get re-enabled in the near future anyway.
A special case is also added for when Status.CU1 is set while FR=0 and
the MSA state is live. In this case we are at risk of getting reserved
instruction exceptions if we try and save the MSA state, so we lose the
MSA state sooner while MSA is still usable.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
James Hogan [Thu, 5 Mar 2015 11:43:36 +0000 (11:43 +0000)]
MIPS: KVM: Add base guest MSA support
Add base code for supporting the MIPS SIMD Architecture (MSA) in MIPS
KVM guests. MSA cannot yet be enabled in the guest, we're just laying
the groundwork.
As with the FPU, whether the guest's MSA context is loaded is stored in
another bit in the fpu_inuse vcpu member. This allows MSA to be disabled
when the guest disables it, but keeping the MSA context loaded so it
doesn't have to be reloaded if the guest re-enables it.
New assembly code is added for saving and restoring the MSA context,
restoring only the upper half of the MSA context (for if the FPU context
is already loaded) and for saving/clearing and restoring MSACSR (which
can itself cause an MSA FP exception depending on the value). The MSACSR
is restored before returning to the guest if MSA is already enabled, and
the existing FP exception die notifier is extended to catch the possible
MSA FP exception and step over the ctcmsa instruction.
The helper function kvm_own_msa() is added to enable MSA and restore
the MSA context if it isn't already loaded, which will be used in a
later patch when the guest attempts to use MSA for the first time and
triggers an MSA disabled exception.
The existing FPU helpers are extended to handle MSA. kvm_lose_fpu()
saves the full MSA context if it is loaded (which includes the FPU
context) and both kvm_lose_fpu() and kvm_drop_fpu() disable MSA.
kvm_own_fpu() also needs to lose any MSA context if FR=0, since there
would be a risk of getting reserved instruction exceptions if CU1 is
enabled and we later try and save the MSA context. We shouldn't usually
hit this case since it will be handled when emulating CU1 changes,
however there's nothing to stop the guest modifying the Status register
directly via the comm page, which will cause this case to get hit.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
James Hogan [Tue, 2 Dec 2014 15:48:24 +0000 (15:48 +0000)]
MIPS: KVM: Expose FPU registers
Add KVM register numbers for the MIPS FPU registers, and implement
access to them with the KVM_GET_ONE_REG / KVM_SET_ONE_REG ioctls when
the FPU capability is enabled (exposed in a later patch) and present in
the guest according to its Config1.FP bit.
The registers are accessible in the current mode of the guest, with each
sized access showing what the guest would see with an equivalent access,
and like the architecture they may become UNPREDICTABLE if the FR mode
is changed. When FR=0, odd doubles are inaccessible as they do not exist
in that mode.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Cc: linux-api@vger.kernel.org Cc: linux-doc@vger.kernel.org
James Hogan [Fri, 6 Feb 2015 10:56:27 +0000 (10:56 +0000)]
MIPS: KVM: Add FP exception handling
Add guest exception handling for floating point exceptions and
coprocessor 1 unusable exceptions.
Floating point exceptions from the guest need passing to the guest
kernel, so for these a guest FPE is emulated.
Also, coprocessor 1 unusable exceptions are normally passed straight
through to the guest (because no guest FPU was supported), but the
hypervisor can now handle them if the guest has its FPU enabled by
restoring the guest FPU context and enabling the FPU.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
James Hogan [Tue, 3 Feb 2015 13:59:38 +0000 (13:59 +0000)]
MIPS: KVM: Emulate FPU bits in COP0 interface
Emulate FPU related parts of COP0 interface so that the guest will be
able to enable/disable the following once the FPU capability has been
wired up:
- The FPU (Status.CU1)
- 64-bit FP register mode (Status.FR)
- Hybrid FP register mode (Config5.FRE)
Changing Status.CU1 has no immediate effect if the FPU state isn't live,
as the FPU state is restored lazily on first use. After that, changes
take place immediately in the host Status.CU1, so that the guest can
start getting coprocessor unusable exceptions right away for guest FPU
operations if it is disabled. The FPU state is saved lazily too, as the
FPU may get re-enabled in the near future anyway.
Any change to Status.FR causes the FPU state to be discarded and FPU
disabled, as the register state is architecturally UNPREDICTABLE after
such a change. This should also ensure that the FPU state is fully
initialised (with stale state, but that's fine) when it is next used in
the new FP mode.
Any change to the Config5.FRE bit is immediately updated in the host
state so that the guest can get the relevant exceptions right away for
single-precision FPU operations.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
James Hogan [Tue, 18 Nov 2014 14:09:12 +0000 (14:09 +0000)]
MIPS: KVM: Add base guest FPU support
Add base code for supporting FPU in MIPS KVM guests. The FPU cannot yet
be enabled in the guest, we're just laying the groundwork.
Whether the guest's FPU context is loaded is stored in a bit in the
fpu_inuse vcpu member. This allows the FPU to be disabled when the guest
disables it, but keeping the FPU context loaded so it doesn't have to be
reloaded if the guest re-enables it.
An fpu_enabled vcpu member stores whether userland has enabled the FPU
capability (which will be wired up in a later patch).
New assembly code is added for saving and restoring the FPU context, and
for saving/clearing and restoring FCSR (which can itself cause an FP
exception depending on the value). The FCSR is restored before returning
to the guest if the FPU is already enabled, and a die notifier is
registered to catch the possible FP exception and step over the ctc1
instruction.
The helper function kvm_lose_fpu() is added to save FPU context and
disable the FPU, which is used when saving hardware state before a
context switch or KVM exit (the vcpu_get_regs() callback).
The helper function kvm_own_fpu() is added to enable the FPU and restore
the FPU context if it isn't already loaded, which will be used in a
later patch when the guest attempts to use the FPU for the first time
and triggers a co-processor unusable exception.
The helper function kvm_drop_fpu() is added to discard the FPU context
and disable the FPU, which will be used in a later patch when the FPU
state will become architecturally UNPREDICTABLE (change of FR mode) to
force a reload of [stale] context in the new FR mode.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
Add a vcpu_get_regs() and vcpu_set_regs() callbacks for loading and
restoring context which may be in hardware registers. This may include
floating point and MIPS SIMD Architecture (MSA) state which may be
accessed directly by the guest (but restored lazily by the hypervisor),
and also dedicated guest registers as provided by the VZ ASE.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
James Hogan [Thu, 26 Jun 2014 14:11:29 +0000 (15:11 +0100)]
MIPS: KVM: Add Config4/5 and writing of Config registers
Add Config4 and Config5 co-processor 0 registers, and add capability to
write the Config1, Config3, Config4, and Config5 registers using the KVM
API.
Only supported bits can be written, to minimise the chances of the guest
being given a configuration from e.g. QEMU that is inconsistent with
that being emulated, and as such the handling is in trap_emul.c as it
may need to be different for VZ. Currently the only modification
permitted is to make Config4 and Config5 exist via the M bits, but other
bits will be added for FPU and MSA support in future patches.
Care should be taken by userland not to change bits without fully
handling the possible extra state that may then exist and which the
guest may begin to use and depend on.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
Various semi-used definitions exist in kvm_host.h for the default guest
config registers. Remove them and use the appropriate values directly
when initialising the Config registers.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
James Hogan [Thu, 26 Jun 2014 12:56:52 +0000 (13:56 +0100)]
MIPS: KVM: Implement PRid CP0 register access
Implement access to the guest Processor Identification CP0 register
using the KVM_GET_ONE_REG and KVM_SET_ONE_REG ioctls. This allows the
owning process to modify and read back the value that is exposed to the
guest in this register.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
James Hogan [Fri, 6 Feb 2015 16:03:57 +0000 (16:03 +0000)]
MIPS: KVM: Handle TRAP exceptions from guest kernel
Trap instructions are used by Linux to implement BUG_ON(), however KVM
doesn't pass trap exceptions on to the guest if they occur in guest
kernel mode, instead triggering an internal error "Exception Code: 13,
not yet handled". The guest kernel then doesn't get a chance to print
the usual BUG message and stack trace.
Implement handling of the trap exception so that it gets passed to the
guest and the user is left with a more useful log message.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org
James Hogan [Tue, 2 Dec 2014 13:44:13 +0000 (13:44 +0000)]
MIPS: Clear [MSA]FPE CSR.Cause after notify_die()
When handling floating point exceptions (FPEs) and MSA FPEs the Cause
bits of the appropriate control and status register (FCSR for FPEs and
MSACSR for MSA FPEs) are read and cleared before enabling interrupts,
presumably so that it doesn't have to go through the pain of restoring
those bits if the process is pre-empted, since writing those bits would
cause another immediate exception while still in the kernel.
The bits aren't normally ever restored again, since userland never
expects to see them set.
However for virtualisation it is necessary for the kernel to be able to
restore these Cause bits, as the guest may have been interrupted in an
FP exception handler but before it could read the Cause bits. This can
be done by registering a die notifier, to get notified of the exception
when such a value is restored, and if the PC was at the instruction
which is used to restore the guest state, the handler can step over it
and continue execution. The Cause bits can then remain set without
causing further exceptions.
For this to work safely a few changes are made:
- __build_clear_fpe and __build_clear_msa_fpe no longer clear the Cause
bits, and now return from exception level with interrupts disabled
instead of enabled.
- do_fpe() now clears the Cause bits and enables interrupts after
notify_die() is called, so that the notifier can chose to return from
exception without this happening.
- do_msa_fpe() acts similarly, but now actually makes use of the second
argument (msacsr) and calls notify_die() with the new DIE_MSAFP,
allowing die notifiers to be informed of MSA FPEs too.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org
James Hogan [Fri, 6 Feb 2015 11:11:56 +0000 (11:11 +0000)]
MIPS: KVM: Handle MSA Disabled exceptions from guest
Guest user mode can generate a guest MSA Disabled exception on an MSA
capable core by simply trying to execute an MSA instruction. Since this
exception is unknown to KVM it will be passed on to the guest kernel.
However guest Linux kernels prior to v3.15 do not set up an exception
handler for the MSA Disabled exception as they don't support any MSA
capable cores. This results in a guest OS panic.
Since an older processor ID may be being emulated, and MSA support is
not advertised to the guest, the correct behaviour is to generate a
Reserved Instruction exception in the guest kernel so it can send the
guest process an illegal instruction signal (SIGILL), as would happen
with a non-MSA-capable core.
Fix this as minimally as reasonably possible by preventing
kvm_mips_check_privilege() from relaying MSA Disabled exceptions from
guest user mode to the guest kernel, and handling the MSA Disabled
exception by emulating a Reserved Instruction exception in the guest,
via a new handle_msa_disabled() KVM callback.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Cc: <stable@vger.kernel.org> # v3.15+
James Hogan [Fri, 27 Mar 2015 19:03:40 +0000 (19:03 +0000)]
Merge branch '4.1-fp' of git://git.linux-mips.org/pub/scm/ralf/upstream-sfr into kvm_mips_queue
MIPS FP/MSA fixes from the MIPS tree. Includes a fix to ensure that the
FPU is properly disabled by lose_fpu() when MSA is in use, and Paul
Burton's "FP/MSA fixes" patchset which is required for FP/MSA support in
KVM:
> This series fixes a bunch of bugs, both build & runtime, with FP & MSA
> support. Most of them only affect systems with the new FP modes & MSA
> support enabled but patch 6 in particular is more general, fixing
> problems for mips64 systems.
James Hogan [Fri, 30 Jan 2015 12:09:39 +0000 (12:09 +0000)]
MIPS: MSA: Fix big-endian FPR_IDX implementation
The maximum word size is 64-bits since MSA state is saved using st.d
which stores two 64-bit words, therefore reimplement FPR_IDX using xor,
and only within each 64-bit word.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9169/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The basic premise of the patch was incorrect since MSA context
(including FP state) is saved using st.d which stores two consecutive
64-bit words in memory rather than a single 128-bit word. This means
that even with big endian MSA, the FP state is still in the first 64-bit
word.
Signed-off-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9168/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Fri, 30 Jan 2015 12:09:37 +0000 (12:09 +0000)]
MIPS: disable FPU if the mode is unsupported
The expected semantics of __enable_fpu are for the FPU to be enabled
in the given mode if possible, otherwise for the FPU to be left
disabled and SIGFPE returned. The FPU was incorrectly being left
enabled in cases where the desired value for FR was unavailable.
Without ensuring the FPU is disabled in this case, it would be
possible for userland to go on to execute further FP instructions
natively in the incorrect mode, rather than those instructions being
trapped & emulated as they need to be.
Paul Burton [Fri, 30 Jan 2015 12:09:36 +0000 (12:09 +0000)]
MIPS: prevent FP context set via ptrace being discarded
If a ptracee has not used the FPU and the ptracer sets its FP context
using PTRACE_POKEUSR, PTRACE_SETFPREGS or PTRACE_SETREGSET then that
context will be discarded upon either the ptracee using the FPU or a
further write to the context via ptrace. Prevent this loss by recording
that the task has "used" math once its FP context has been written to.
The context initialisation code that was present for the PTRACE_POKEUSR
case is reused for the other 2 cases to provide consistent behaviour
for the different ptrace requests.
Paul Burton [Fri, 30 Jan 2015 12:09:35 +0000 (12:09 +0000)]
MIPS: Ensure FCSR cause bits are clear after invoking FPU emulator
When running the emulator to handle an instruction that raised an FP
unimplemented operation exception, the FCSR cause bits were being
cleared. This is done to ensure that the kernel does not take an FP
exception when later restoring FP context to registers. However, this
was not being done when the emulator is invoked in response to a
coprocessor unusable exception. This happens in 2 cases:
- There is no FPU present in the system. In this case things were
OK, since the FP context is never restored to hardware registers
and thus no FP exception may be raised when restoring FCSR.
- The FPU could not be configured to the mode required by the task.
In this case it would be possible for the emulator to set cause
bits which are later restored to hardware if the task migrates
to a CPU whose associated FPU does support its mode requirements,
or if the tasks FP mode requirements change.
Consistently clear the cause bits after invoking the emulator, by moving
the clearing to process_fpemu_return and ensuring this is always called
before the tasks FP context is restored. This will make it easier to
catch further paths invoking the emulator in future, as will be
introduced in further patches.
Paul Burton [Fri, 30 Jan 2015 12:09:34 +0000 (12:09 +0000)]
MIPS: clear MSACSR cause bits when handling MSA FP exception
Much like for traditional scalar FP exceptions, the cause bits in the
MSACSR register need to be cleared following an MSA FP exception.
Without doing so the exception will simply be raised again whenever
the kernel restores MSACSR from a tasks saved context, leading to
undesirable spurious exceptions. Clear the cause bits from the
handle_msa_fpe function, mirroring the way handle_fpe clears the
cause bits in FCSR.
Paul Burton [Fri, 30 Jan 2015 12:09:33 +0000 (12:09 +0000)]
MIPS: wrap cfcmsa & ctcmsa accesses for toolchains with MSA support
Uses of the cfcmsa & ctcmsa instructions were not being wrapped by a
macro in the case where the toolchain supports MSA, since the arguments
exactly match a typical use of the instructions. However using current
toolchains this leads to errors such as:
arch/mips/kernel/genex.S:437: Error: opcode not supported on this processor: mips32r2 (mips32r2) `cfcmsa $5,1'
Thus uses of the instructions must be in the context of a ".set msa"
directive, however doing that from the users of the instructions would
be messy due to the possibility that the toolchain does not support
MSA. Fix this by renaming the macros (prepending an underscore) in order
to avoid recursion when attempting to emit the instructions, and provide
implementations for the TOOLCHAIN_SUPPORTS_MSA case which ".set msa" as
appropriate.
Paul Burton [Fri, 30 Jan 2015 12:09:32 +0000 (12:09 +0000)]
MIPS: remove MSA macro recursion
Recursive macros made the code more concise & worked great for the
case where the toolchain doesn't support MSA. However, with toolchains
which do support MSA they lead to build failures such as:
Paul Burton [Fri, 30 Jan 2015 12:09:31 +0000 (12:09 +0000)]
MIPS: assume at as source/dest of MSA copy/insert instructions
Assuming at ($1) as the source or destination register of copy or
insert instructions:
- Simplifies the macros providing those instructions for toolchains
without MSA support.
- Avoids an unnecessary move instruction when at is used as the source
or destination register anyway.
- Is sufficient for the uses to be introduced in the kernel by a
subsequent patch.
Note that due to a patch ordering snafu on my part this also fixes the
currently broken build with MSA support enabled. The build has been
broken since commit c9017757c532 "MIPS: init upper 64b of vector
registers when MSA is first used", which this patch should have
preceeded.
Paul Burton [Fri, 27 Mar 2015 17:00:03 +0000 (17:00 +0000)]
MIPS: Push .set mips64r* into the functions needing it
The {save,restore}_fp_context{,32} functions require that the assembler
allows the use of sdc instructions on any FP register, and this is
acomplished by setting the arch to mips64r2 or mips64r6
(using MIPS_ISA_ARCH_LEVEL_RAW).
However this has the effect of enabling the assembler to use mips64
instructions in the expansion of pseudo-instructions. This was done in
the (now-reverted) commit eec43a224cf1 "MIPS: Save/restore MSA context
around signals" which led to my mistakenly believing that there was an
assembler bug, when in reality the assembler was just emitting mips64
instructions. Avoid the issue for future commits which will add code to
r4k_fpu.S by pushing the .set MIPS_ISA_ARCH_LEVEL_RAW directives into
the functions that require it, and remove the spurious assertion
declaring the assembler bug.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
[james.hogan@imgtec.com: Rebase on v4.0-rc1 and reword commit message to
reflect use of MIPS_ISA_ARCH_LEVEL_RAW] Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9612/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
James Hogan [Wed, 25 Feb 2015 13:08:05 +0000 (13:08 +0000)]
MIPS: lose_fpu(): Disable FPU when MSA enabled
The lose_fpu() function only disables the FPU in CP0_Status.CU1 if the
FPU is in use and MSA isn't enabled.
This isn't necessarily a problem because KSTK_STATUS(current), the
version of CP0_Status stored on the kernel stack on entry from user
mode, does always get updated and gets restored when returning to user
mode, but I don't think it was intended, and it is inconsistent with the
case of only the FPU being in use. Sometimes leaving the FPU enabled may
also mask kernel bugs where FPU operations are executed when the FPU
might not be enabled.
So lets disable the FPU in the MSA case too.
Fixes: 33c771ba5c5d ("MIPS: save/disable MSA in lose_fpu") Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9323/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Jan Kiszka [Mon, 23 Mar 2015 18:27:19 +0000 (19:27 +0100)]
KVM: nVMX: Add support for rdtscp
If the guest CPU is supposed to support rdtscp and the host has rdtscp
enabled in the secondary execution controls, we can also expose this
feature to L1. Just extend nested_vmx_exit_handled to properly route
EXIT_REASON_RDTSCP.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Andre Przywara [Thu, 26 Mar 2015 14:39:34 +0000 (14:39 +0000)]
KVM: arm/arm64: implement kvm_io_bus MMIO handling for the VGIC
Currently we use a lot of VGIC specific code to do the MMIO
dispatching.
Use the previous reworks to add kvm_io_bus style MMIO handlers.
Those are not yet called by the MMIO abort handler, also the actual
VGIC emulator function do not make use of it yet, but will be enabled
with the following patches.
Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Andre Przywara [Thu, 26 Mar 2015 14:39:33 +0000 (14:39 +0000)]
KVM: arm/arm64: simplify vgic_find_range() and callers
The vgic_find_range() function in vgic.c takes a struct kvm_exit_mmio
argument, but actually only used the length field in there. Since we
need to get rid of that structure in that part of the code anyway,
let's rework the function (and it's callers) to pass the length
argument to the function directly.
Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Andre Przywara [Thu, 26 Mar 2015 14:39:32 +0000 (14:39 +0000)]
KVM: arm/arm64: rename struct kvm_mmio_range to vgic_io_range
The name "kvm_mmio_range" is a bit bold, given that it only covers
the VGIC's MMIO ranges. To avoid confusion with kvm_io_range, rename
it to vgic_io_range.
Signed-off-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Andre Przywara [Thu, 26 Mar 2015 14:39:31 +0000 (14:39 +0000)]
KVM: x86: remove now unneeded include directory from Makefile
virt/kvm was never really a good include directory for anything else
than locally included headers.
With the move of iodev.h there is no need anymore to add this
directory the compiler's include path, so remove it from the x86 kvm
Makefile.
Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Andre Przywara [Thu, 26 Mar 2015 14:39:30 +0000 (14:39 +0000)]
KVM: arm/arm64: remove now unneeded include directory from Makefile
virt/kvm was never really a good include directory for anything else
than locally included headers.
With the move of iodev.h there is no need anymore to add this
directory the compiler's include path, so remove it from the arm and
arm64 kvm Makefile.
Signed-off-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Andre Przywara [Thu, 26 Mar 2015 14:39:29 +0000 (14:39 +0000)]
KVM: move iodev.h from virt/kvm/ to include/kvm
iodev.h contains definitions for the kvm_io_bus framework. This is
needed both by the generic KVM code in virt/kvm as well as by
architecture specific code under arch/. Putting the header file in
virt/kvm and using local includes in the architecture part seems at
least dodgy to me, so let's move the file into include/kvm, so that a
more natural "#include <kvm/iodev.h>" can be used by all of the code.
This also solves a problem later when using struct kvm_io_device
in arm_vgic.h.
Fixing up the FSF address in the GPL header and a wrong include path
on the way.
Signed-off-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Nikolay Nikolaev [Thu, 26 Mar 2015 14:39:28 +0000 (14:39 +0000)]
KVM: Redesign kvm_io_bus_ API to pass VCPU structure to the callbacks.
This is needed in e.g. ARM vGIC emulation, where the MMIO handling
depends on the VCPU that does the access.
Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Marcelo Tosatti [Mon, 23 Mar 2015 23:32:02 +0000 (20:32 -0300)]
Merge tag 'kvm-s390-next-20150318' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into queue
KVM: s390: Features and fixes for 4.1 (kvm/next)
1. Fixes
2. Implement access register mode in KVM
3. Provide a userspace post handler for the STSI instruction
4. Provide an interface for compliant memory accesses
5. Provide an interface for getting/setting the guest storage key
6. Fixup for the vector facility patches: do not announce the
vector facility in the guest for old QEMUs.
1-5 were initially shown as RFC in
http://www.spinics.net/lists/kvm/msg114720.html
some small review changes
- added some ACKs
- have the AR mode patches first
- get rid of unnecessary AR_INVAL define
- typos and language
6. two new patches
The two new patches fixup the vector support patches that were
introduced in the last pull request for QEMU versions that dont
know about vector support and guests that do. (We announce the
facility bit, but dont enable the facility so vector aware guests
will crash on vector instructions).
Takuya Yoshikawa [Tue, 17 Mar 2015 07:19:58 +0000 (16:19 +0900)]
KVM: Eliminate extra function calls in kvm_get_dirty_log_protect()
When all bits in mask are not set,
kvm_arch_mmu_enable_log_dirty_pt_masked() has nothing to do. But since
it needs to be called from the generic code, it cannot be inlined, and
a few function calls, two when PML is enabled, are wasted.
Since it is common to see many pages remain clean, e.g. framebuffers can
stay calm for a long time, it is worth eliminating this overhead.
Xiubo Li [Fri, 13 Mar 2015 09:39:45 +0000 (17:39 +0800)]
KVM: x86: For the symbols used locally only should be static type
This patch fix the following sparse warnings:
for arch/x86/kvm/x86.c:
warning: symbol 'emulator_read_write' was not declared. Should it be static?
warning: symbol 'emulator_write_emulated' was not declared. Should it be static?
warning: symbol 'emulator_get_dr' was not declared. Should it be static?
warning: symbol 'emulator_set_dr' was not declared. Should it be static?
for arch/x86/kvm/pmu.c:
warning: symbol 'fixed_pmc_events' was not declared. Should it be static?
Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Michael Mueller [Mon, 16 Mar 2015 15:05:41 +0000 (16:05 +0100)]
KVM: s390: represent SIMD cap in kvm facility
The patch represents capability KVM_CAP_S390_VECTOR_REGISTERS by means
of the SIMD facility bit. This allows to a) disable the use of SIMD when
used in conjunction with a not-SIMD-aware QEMU, b) to enable SIMD when
used with a SIMD-aware version of QEMU and c) finally by means of a QEMU
version using the future cpu model ioctls.
Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com> Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com> Tested-by: Eric Farman <farman@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Michael Mueller [Tue, 17 Mar 2015 10:03:07 +0000 (11:03 +0100)]
KVM: s390: drop SIMD bit from kvm_s390_fac_list_mask
Setting the SIMD bit in the KVM mask is an issue because it makes the
facility visible but not usable to the guest, thus it needs to be
removed again.
Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com> Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Jason J. Herne [Tue, 23 Sep 2014 13:23:01 +0000 (09:23 -0400)]
KVM: s390: Create ioctl for Getting/Setting guest storage keys
Provide the KVM_S390_GET_SKEYS and KVM_S390_SET_SKEYS ioctl which can be used
to get/set guest storage keys. This functionality is needed for live migration
of s390 guests that use storage keys.
Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The Store System Information (STSI) instruction currently collects all
information it relays to the caller in the kernel. Some information,
however, is only available in user space. An example of this is the
guest name: The kernel always sets "KVMGuest", but user space knows the
actual guest name.
This patch introduces a new exit, KVM_EXIT_S390_STSI, guarded by a
capability that can be enabled by user space if it wants to be able to
insert such data. User space will be provided with the target buffer
and the requested STSI function code.
Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Thomas Huth [Fri, 6 Feb 2015 14:01:21 +0000 (15:01 +0100)]
KVM: s390: Add MEMOP ioctls for reading/writing guest memory
On s390, we've got to make sure to hold the IPTE lock while accessing
logical memory. So let's add an ioctl for reading and writing logical
memory to provide this feature for userspace, too.
The maximum transfer size of this call is limited to 64kB to prevent
that the guest can trigger huge copy_from/to_user transfers. QEMU
currently only requests up to one or two pages so far, so 16*4kB seems
to be a reasonable limit here.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Access register mode is one of the modes that control dynamic address
translation. In this mode the address space is specified by values of
the access registers. The effective address-space-control element is
obtained from the result of the access register translation. See
the "Access-Register Introduction" section of the chapter 5 "Program
Execution" in "Principles of Operations" for more details.
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390: Optimize paths where get_vcpu_asce() is invoked
During dynamic address translation the get_vcpu_asce()
function can be invoked several times. It's ok for usual modes, but will
be slow if CPUs are in AR mode. Let's call the get_vcpu_asce() once and
pass the result to the called functions.
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390: Guest's memory access functions get access registers
In access register mode, the write_guest() read_guest() and other
functions will invoke the access register translation, which
requires an ar, designated by one of the instruction fields.
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390: Fix low-address protection for real addresses
The kvm_s390_check_low_addr_protection() function is used only with real
addresses. According to the POP (the "Low-Address Protection"
paragraph in chapter 3), if the effective address is real or absolute,
the low-address protection procedure should raise a PROTECTION exception
only when the low-address protection is enabled in the control register
0 and the address is low.
This patch removes ASCE checks from the function and renames it to
better reflect its behavior.
Cc: Thomas Huth <thuth@linux.vnet.ibm.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Christoffer Dall [Fri, 13 Mar 2015 17:02:55 +0000 (17:02 +0000)]
arm/arm64: KVM: Fix migration race in the arch timer
When a VCPU is no longer running, we currently check to see if it has a
timer scheduled in the future, and if it does, we schedule a host
hrtimer to notify is in case the timer expires while the VCPU is still
not running. When the hrtimer fires, we mask the guest's timer and
inject the timer IRQ (still relying on the guest unmasking the time when
it receives the IRQ).
This is all good and fine, but when migration a VM (checkpoint/restore)
this introduces a race. It is unlikely, but possible, for the following
sequence of events to happen:
1. Userspace stops the VM
2. Hrtimer for VCPU is scheduled
3. Userspace checkpoints the VGIC state (no pending timer interrupts)
4. The hrtimer fires, schedules work in a workqueue
5. Workqueue function runs, masks the timer and injects timer interrupt
6. Userspace checkpoints the timer state (timer masked)
At restore time, you end up with a masked timer without any timer
interrupts and your guest halts never receiving timer interrupts.
Fix this by only kicking the VCPU in the workqueue function, and sample
the expired state of the timer when entering the guest again and inject
the interrupt and mask the timer only then.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Christoffer Dall [Fri, 13 Mar 2015 17:02:54 +0000 (17:02 +0000)]
arm/arm64: KVM: support for un-queuing active IRQs
Migrating active interrupts causes the active state to be lost
completely. This implements some additional bitmaps to track the active
state on the distributor and export this to user space.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Alex Bennée [Fri, 13 Mar 2015 17:02:52 +0000 (17:02 +0000)]
arm/arm64: KVM: export VCPU power state via MP_STATE ioctl
To cleanly restore an SMP VM we need to ensure that the current pause
state of each vcpu is correctly recorded. Things could get confused if
the CPU starts running after migration restore completes when it was
paused before it state was captured.
We use the existing KVM_GET/SET_MP_STATE ioctl to do this. The arm/arm64
interface is a lot simpler as the only valid states are
KVM_MP_STATE_RUNNABLE and KVM_MP_STATE_STOPPED.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Christoffer Dall [Fri, 13 Mar 2015 17:02:56 +0000 (17:02 +0000)]
arm/arm64: KVM: Keep elrsr/aisr in sync with software model
There is an interesting bug in the vgic code, which manifests itself
when the KVM run loop has a signal pending or needs a vmid generation
rollover after having disabled interrupts but before actually switching
to the guest.
In this case, we flush the vgic as usual, but we sync back the vgic
state and exit to userspace before entering the guest. The consequence
is that we will be syncing the list registers back to the software model
using the GICH_ELRSR and GICH_EISR from the last execution of the guest,
potentially overwriting a list register containing an interrupt.
This showed up during migration testing where we would capture a state
where the VM has masked the arch timer but there were no interrupts,
resulting in a hung test.
Cc: Marc Zyngier <marc.zyngier@arm.com> Reported-by: Alex Bennee <alex.bennee@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Jan Kiszka [Mon, 9 Mar 2015 19:56:43 +0000 (20:56 +0100)]
KVM: nVMX: Do not emulate #UD while in guest mode
While in L2, leave all #UD to L2 and do not try to emulate it. If L1 is
interested in doing this, it reports its interest via the exception
bitmap, and we never get into handle_exception of L0 anyway.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Jan Kiszka [Mon, 9 Mar 2015 19:27:43 +0000 (20:27 +0100)]
KVM: x86: Fix re-execution of patched vmmcall
For a very long time (since 2b3d2a20), the path handling a vmmcall
instruction of the guest on an Intel host only applied the patch but no
longer handled the hypercall. The reverse case, vmcall on AMD hosts, is
fine. As both em_vmcall and em_vmmcall actually have to do the same, we
can fix the issue by consolidating both into the same handler.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
David Kaplan [Fri, 6 Mar 2015 20:44:35 +0000 (14:44 -0600)]
x86: svm: use cr_interception for SVM_EXIT_CR0_SEL_WRITE
Another patch in my war on emulate_on_interception() use as a svm exit handler.
These were pulled out of a larger patch at the suggestion of Radim Krcmar, see
https://lkml.org/lkml/2015/2/25/559
Changes since v1:
* fixed typo introduced after test, retested
Signed-off-by: David Kaplan <david.kaplan@amd.com>
[separated out just cr_interception part from larger removal of
INTERCEPT_CR0_WRITE, forward ported, tested] Signed-off-by: Joel Schopp <joel.schopp@amd.com> Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Marcelo Tosatti [Fri, 13 Mar 2015 01:09:35 +0000 (22:09 -0300)]
Merge tag 'kvm-s390-next-20150306' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into queue
KVM: s390: Features and Fixes for 4.1 (kvm/next)
1. Several Fixes and enhancements
---------------------------------
- These 3 patches have cc stable: b75f4c9 KVM: s390: Zero out current VMDB of STSI before including level3 data. 261520d KVM: s390: fix handling of write errors in the tpi handler 15462e3 KVM: s390: reinjection of irqs can fail in the tpi handler
2. SIMD support the kernel part (introduced with z13)
-----------------------------------------------------
- two KVM-generic changes in kvm.h:
1. New capability that can be enabled: KVM_CAP_S390_VECTOR_REGISTERS
2. increased padding size for sync regs in struct kvm_run to clarify that
sync regs can be larger than 1k. This is fine as this is the last
element in the structure.
Marc Zyngier [Thu, 12 Mar 2015 18:16:52 +0000 (18:16 +0000)]
arm/arm64: KVM: Optimize handling of Access Flag faults
Now that we have page aging in Stage-2, it becomes obvious that
we're doing way too much work handling the fault.
The page is not going anywhere (it is still mapped), the page
tables are already allocated, and all we want is to flip a bit
in the PMD or PTE. Also, we can avoid any form of TLB invalidation,
since a page with the AF bit off is not allowed to be cached.
An obvious solution is to have a separate handler for FSC_ACCESS,
where we pride ourselves to only do the very minimum amount of
work.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Marc Zyngier [Thu, 12 Mar 2015 18:16:51 +0000 (18:16 +0000)]
arm/arm64: KVM: Implement Stage-2 page aging
Until now, KVM/arm didn't care much for page aging (who was swapping
anyway?), and simply provided empty hooks to the core KVM code. With
server-type systems now being available, things are quite different.
This patch implements very simple support for page aging, by clearing
the Access flag in the Stage-2 page tables. On access fault, the current
fault handling will write the PTE or PMD again, putting the Access flag
back on.
It should be possible to implement a much faster handling for Access
faults, but that's left for a later patch.
With this in place, performance in VMs is degraded much more gracefully.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Marc Zyngier [Thu, 12 Mar 2015 18:16:50 +0000 (18:16 +0000)]
arm/arm64: KVM: Allow handle_hva_to_gpa to return a value
So far, handle_hva_to_gpa was never required to return a value.
As we prepare to age pages at Stage-2, we need to be able to
return a value from the iterator (kvm_test_age_hva).
Adapt the code to handle this situation. No semantic change.
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>
Eric Auger [Wed, 4 Mar 2015 10:14:36 +0000 (11:14 +0100)]
KVM: arm/arm64: add irqfd support
This patch enables irqfd on arm/arm64.
Both irqfd and resamplefd are supported. Injection is implemented
in vgic.c without routing.
This patch enables CONFIG_HAVE_KVM_EVENTFD and CONFIG_HAVE_KVM_IRQFD.
KVM_CAP_IRQFD is now advertised. KVM_CAP_IRQFD_RESAMPLE capability
automatically is advertised as soon as CONFIG_HAVE_KVM_IRQFD is set.
Irqfd injection is restricted to SPI. The rationale behind not
supporting PPI irqfd injection is that any device using a PPI would
be a private-to-the-CPU device (timer for instance), so its state
would have to be context-switched along with the VCPU and would
require in-kernel wiring anyhow. It is not a relevant use case for
irqfds.
Signed-off-by: Eric Auger <eric.auger@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Eric Auger [Wed, 4 Mar 2015 10:14:35 +0000 (11:14 +0100)]
KVM: arm/arm64: remove coarse grain dist locking at kvm_vgic_sync_hwstate
To prepare for irqfd addition, coarse grain locking is removed at
kvm_vgic_sync_hwstate level and finer grain locking is introduced in
vgic_process_maintenance only.
Signed-off-by: Eric Auger <eric.auger@linaro.org> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
On arm/arm64 the VGIC is dynamically instantiated and it is useful
to expose its state, especially for irqfd setup.
This patch defines __KVM_HAVE_ARCH_INTC_INITIALIZED and
implements kvm_arch_intc_initialized.
Signed-off-by: Eric Auger <eric.auger@linaro.org> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
projects / karo-tx-linux.git / log