Commit Graph
32 Commits
Author SHA1 Message Date
Liran Alon 23accdf162 hw/i386/vmport: Assert vmport initialized before registering commands
vmport_register() is also called from other modules such as vmmouse.
Therefore, these modules rely that vmport is realized before those call
sites. If this is violated, vmport_register() will NULL-deref.

To make such issues easier to debug, assert in vmport_register() that
vmport is already realized.

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200312165431.82118-17-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:54 -04:00
Liran Alon d6048bfd12 hw/i386/vmport: Add support for CMD_GETHZ
This command returns to guest information on LAPIC bus frequency and TSC
frequency.

One can see how this interface is used by Linux vmware_platform_setup()
introduced in Linux commit 88b094fb8d4f ("x86: Hypervisor detection and
get tsc_freq from hypervisor").

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200312165431.82118-16-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:53 -04:00
Liran Alon 73b994f6d7 i386/cpu: Store LAPIC bus frequency in CPU structure
No functional change.
This information will be used by following patches.

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200312165431.82118-15-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:52 -04:00
Liran Alon 7f9114b77c hw/i386/vmport: Allow x2apic without IR
Signal to guest that hypervisor supports x2apic without VT-d/IOMMU
Interrupt-Remapping support. This allows guest to use x2apic in
case all APIC IDs fits in 8-bit (i.e. Max APIC ID < 255).

See Linux kernel commit 4cca6ea04d31 ("x86/apic: Allow x2apic
without IR on VMware platform") and Linux try_to_enable_x2apic()
function.

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200312165431.82118-14-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:50 -04:00
Liran Alon acacd3550b hw/i386/vmport: Add support for CMD_GET_VCPU_INFO
Command currently returns that it is unimplemented by setting
the reserved-bit in it's return value.

Following patches will return various useful vCPU information
to guest.

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200312165431.82118-13-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:47 -04:00
Liran Alon aaacf1c15a hw/i386/vmport: Add support for CMD_GETBIOSUUID
This is VMware documented functionallity that some guests rely on.
Returns the BIOS UUID of the current virtual machine.

Note that we also introduce a new compatability flag "x-cmds-v2" to
make sure to expose new VMPort commands only to new machine-types.
This flag will also be used by the following patches that will introduce
additional VMPort commands.

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200312165431.82118-10-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:47 -04:00
Liran Alon dcd938f032 hw/i386/vmport: Define enum for all commands
No functional change.

Defining an enum for all VMPort commands have the following advantages:
* It gets rid of the error-prone requirement to update VMPORT_ENTRIES
when new VMPort commands are added to QEMU.
* It makes it clear to know by looking at one place at the source, what
are all the VMPort commands supported by QEMU.

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200312165431.82118-9-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:46 -04:00
Liran Alon d8f23d619c hw/i386/vmport: Introduce vmport.h
No functional change. This is mere refactoring.

Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200312165431.82118-8-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:45 -04:00
Liran Alon f8bdc55037 hw/i386/vmport: Report vmware-vmx-type in CMD_GETVERSION
As can be seen from VmCheck_GetVersion() in open-vm-tools code,
CMD_GETVERSION should return vmware-vmx-type in ECX register.

Default is to fake host as VMware ESX server. But user can control
this value by "-global vmport.vmware-vmx-type=X".

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200312165431.82118-7-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:45 -04:00
Liran Alon 2fd2f799f8 hw/i386/vmport: Introduce vmware-vmx-version property
vmware-vmx-version is a number returned from CMD_GETVERSION which specifies
to guest VMware Tools the the host VMX version. If the host reports a number
that is different than what the guest VMware Tools expects, it may force
guest to upgrade VMware Tools. (See comment above VERSION_MAGIC and
VmCheck_IsVirtualWorld() function in open-vm-tools open-source code).

For better readability and allow maintaining compatability for guests
which may expect different vmware-vmx-version, make vmware-vmx-version a
VMPort object property. This would allow user to control it's value via
"-global vmport.vmware-vmx-version=X".

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200312165431.82118-6-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:44 -04:00
Liran Alon 0342ee761e hw/i386/vmport: Set EAX to -1 on failed and unsupported commands
This is used as a signal for VMware Tools to know if a command it
attempted to invoke, failed or is unsupported. As a result, VMware Tools
will either report failure to user or fallback to another backdoor command
in attempt to perform some operation.

A few examples:
* open-vm-tools TimeSyncReadHost() function fallbacks to
CMD_GETTIMEFULL command when CMD_GETTIMEFULL_WITH_LAG
fails/unsupported.
* open-vm-tools Hostinfo_NestingSupported() function verifies
EAX != -1 to check for success.
* open-vm-tools Hostinfo_VCPUInfoBackdoor() functions checks
if reserved-bit is set to indicate command is unimplemented.

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200312165431.82118-5-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:44 -04:00
Liran Alon b889212973 hw/i386/vmport: Propagate IOPort read to vCPU EAX register
vmport_ioport_read() returns the value that should propagate to vCPU EAX
register when guest reads VMPort IOPort (i.e. By x86 IN instruction).

However, because vmport_ioport_read() calls cpu_synchronize_state(), the
returned value gets overridden by the value in QEMU vCPU EAX register.
i.e. cpu->env.regs[R_EAX].

To fix this issue, change vmport_ioport_read() to explicitly override
cpu->env.regs[R_EAX] with the value it wish to propagate to vCPU EAX
register.

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200312165431.82118-4-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:43 -04:00
Liran Alon c9ab24cef8 hw/i386/vmport: Add device properties
No functional change.

This is done as a preparation for the following patches that will
introduce several device properties.

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200312165431.82118-3-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:43 -04:00
Liran Alon 29282253b7 hw/i386/vmport: Add reference to VMware open-vm-tools
This official VMware open-source project can be used as reference to
understand how guest code interacts with VMPort virtual device. Thus,
providing understanding on how device is expected to behave.

Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200312165431.82118-2-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:43 -04:00
Liran Alon 1aaef7d809 acpi: unit-test: Update WAET ACPI Table expected binaries
This is done according to step (6) in the process described at
tests/qtest/bios-tables-test.c.

Expected WAET.dsl:

[000h 0000   4]                    Signature : "WAET"    [Windows ACPI Emulated Devices Table]
[004h 0004   4]                 Table Length : 00000028
[008h 0008   1]                     Revision : 01
[009h 0009   1]                     Checksum : 88
[00Ah 0010   6]                       Oem ID : "BOCHS "
[010h 0016   8]                 Oem Table ID : "BXPCWAET"
[018h 0024   4]                 Oem Revision : 00000001
[01Ch 0028   4]              Asl Compiler ID : "BXPC"
[020h 0032   4]        Asl Compiler Revision : 00000001

[024h 0036   4]        Flags (decoded below) : 00000002
                        RTC needs no INT ack : 0
                     PM timer, one read only : 1

Raw Table Data: Length 40 (0x28)

  0000: 57 41 45 54 28 00 00 00 01 88 42 4F 43 48 53 20  // WAET(.....BOCHS
  0010: 42 58 50 43 57 41 45 54 01 00 00 00 42 58 50 43  // BXPCWAET....BXPC
  0020: 01 00 00 00 02 00 00 00                          // ........

Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200313145009.144820-4-liran.alon@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-05-04 10:25:03 -04:00
Liran Alon 14cda3503d acpi: Add Windows ACPI Emulated Device Table (WAET)
Microsoft introduced this ACPI table to avoid Windows guests performing
various workarounds for device erratas. As the virtual device emulated
by VMM may not have the errata.

Currently, WAET allows hypervisor to inform guest about two
specific behaviors: One for RTC and the other for ACPI PM timer.

Support for WAET have been introduced since Windows Vista. This ACPI
table is also exposed by other common hypervisors by default, including:
VMware, GCP and AWS.

This patch adds WAET ACPI Table to QEMU.

We set "ACPI PM timer good" bit in "Emualted Device Flags" field to
indicate that the ACPI PM timer has been enhanced to not require
multiple reads to obtain a reliable value.
This results in improving the performance of Windows guests that use
ACPI PM timer by avoiding unnecessary VMExits caused by these multiple
reads.

Co-developed-by: Elad Gabay <elad.gabay@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200313145009.144820-3-liran.alon@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
2020-05-04 10:25:03 -04:00
Liran Alon 4b773fc2f7 acpi: unit-test: Ignore diff in WAET ACPI table
This is done as a preparation for the following patch to expose WAET
ACPI table to guest.

This patch performs steps 1-3 as describes in
tests/qtest/bios-tables-test.c.

Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200313145009.144820-2-liran.alon@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-05-04 10:25:03 -04:00
Liran Alon 79a197ab18 target/i386: kvm: Demand nested migration kernel capabilities only when vCPU may have enabled VMX
Previous to this change, a vCPU exposed with VMX running on a kernel
without KVM_CAP_NESTED_STATE or KVM_CAP_EXCEPTION_PAYLOAD resulted in
adding a migration blocker. This was because when the code was written
it was thought there is no way to reliably know if a vCPU is utilising
VMX or not at runtime. However, it turns out that this can be known to
some extent:

In order for a vCPU to enter VMX operation it must have CR4.VMXE set.
Since it was set, CR4.VMXE must remain set as long as the vCPU is in
VMX operation. This is because CR4.VMXE is one of the bits set
in MSR_IA32_VMX_CR4_FIXED1.
There is one exception to the above statement when vCPU enters SMM mode.
When a vCPU enters SMM mode, it temporarily exits VMX operation and
may also reset CR4.VMXE during execution in SMM mode.
When the vCPU exits SMM mode, vCPU state is restored to be in VMX operation
and CR4.VMXE is restored to its original state of being set.
Therefore, when the vCPU is not in SMM mode, we can infer whether
VMX is being used by examining CR4.VMXE. Otherwise, we cannot
know for certain but assume the worse that vCPU may utilise VMX.

Summaring all the above, a vCPU may have enabled VMX in case
CR4.VMXE is set or vCPU is in SMM mode.

Therefore, remove migration blocker and check before migration
(cpu_pre_save()) if the vCPU may have enabled VMX. If true, only then
require relevant kernel capabilities.

While at it, demand KVM_CAP_EXCEPTION_PAYLOAD only when the vCPU is in
guest-mode and there is a pending/injected exception. Otherwise, this
kernel capability is not required for proper migration.

Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Maran Wilson <maran.wilson@oracle.com>
Tested-by: Maran Wilson <maran.wilson@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-07-19 18:01:47 +02:00
Liran Alon ec7b1bbd2c target/i386: kvm: Fix when nested state is needed for migration
When vCPU is in VMX operation and enters SMM mode,
it temporarily exits VMX operation but KVM maintained nested-state
still stores the VMXON region physical address, i.e. even when the
vCPU is in SMM mode then (nested_state->hdr.vmx.vmxon_pa != -1ull).

Therefore, there is no need to explicitly check for
KVM_STATE_NESTED_SMM_VMXON to determine if it is necessary
to save nested-state as part of migration stream.

Reviewed-by: Karl Heubaum <karl.heubaum@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20190624230514.53326-1-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-07-05 22:16:46 +02:00
Liran Alon 12604092e2 target/i386: kvm: Add nested migration blocker only when kernel lacks required capabilities
Previous commits have added support for migration of nested virtualization
workloads. This was done by utilising two new KVM capabilities:
KVM_CAP_NESTED_STATE and KVM_CAP_EXCEPTION_PAYLOAD. Both which are
required in order to correctly migrate such workloads.

Therefore, change code to add a migration blocker for vCPUs exposed with
Intel VMX or AMD SVM in case one of these kernel capabilities is
missing.

Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Maran Wilson <maran.wilson@oracle.com>
Message-Id: <20190619162140.133674-11-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-21 13:25:28 +02:00
Liran Alon fd13f23b8c target/i386: kvm: Add support for KVM_CAP_EXCEPTION_PAYLOAD
Kernel commit c4f55198c7c2 ("kvm: x86: Introduce KVM_CAP_EXCEPTION_PAYLOAD")
introduced a new KVM capability which allows userspace to correctly
distinguish between pending and injected exceptions.

This distinguish is important in case of nested virtualization scenarios
because a L2 pending exception can still be intercepted by the L1 hypervisor
while a L2 injected exception cannot.

Furthermore, when an exception is attempted to be injected by QEMU,
QEMU should specify the exception payload (CR2 in case of #PF or
DR6 in case of #DB) instead of having the payload already delivered in
the respective vCPU register. Because in case exception is injected to
L2 guest and is intercepted by L1 hypervisor, then payload needs to be
reported to L1 intercept (VMExit handler) while still preserving
respective vCPU register unchanged.

This commit adds support for QEMU to properly utilise this new KVM
capability (KVM_CAP_EXCEPTION_PAYLOAD).

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20190619162140.133674-10-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-21 13:25:27 +02:00
Liran Alon ebbfef2f34 target/i386: kvm: Add support for save and restore nested state
Kernel commit 8fcc4b5923af ("kvm: nVMX: Introduce KVM_CAP_NESTED_STATE")
introduced new IOCTLs to extract and restore vCPU state related to
Intel VMX & AMD SVM.

Utilize these IOCTLs to add support for migration of VMs which are
running nested hypervisors.

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: Maran Wilson <maran.wilson@oracle.com>
Tested-by: Maran Wilson <maran.wilson@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20190619162140.133674-9-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-21 13:23:47 +02:00
Liran Alon 6cfd763932 vmstate: Add support for kernel integer types
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: Maran Wilson <maran.wilson@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190619162140.133674-8-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-21 13:23:47 +02:00
Liran Alon 1d33bea4d0 linux-headers: sync with latest KVM headers from Linux 5.2
Improve the KVM_{GET,SET}_NESTED_STATE structs by detailing the format
of VMX nested state data in a struct.

In order to avoid changing the ioctl values of
KVM_{GET,SET}_NESTED_STATE, there is a need to preserve
sizeof(struct kvm_nested_state). This is done by defining the data
struct as "data.vmx[0]". It was the most elegant way I found to
preserve struct size while still keeping struct readable and easy to
maintain. It does have a misfortunate side-effect that now it has to be
accessed as "data.vmx[0]" rather than just "data.vmx".

Because we are already modifying these structs, I also modified the
following:
* Define the "format" field values as macros.
* Rename vmcs_pa to vmcs12_pa for better readability.

Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Maran Wilson <maran.wilson@oracle.com>
Message-Id: <20190619162140.133674-7-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-21 13:23:47 +02:00
Liran Alon 18ab37ba1c target/i386: kvm: Block migration for vCPUs exposed with nested virtualization
Commit d98f26073b ("target/i386: kvm: add VMX migration blocker")
added a migration blocker for vCPU exposed with Intel VMX.
However, migration should also be blocked for vCPU exposed with
AMD SVM.

Both cases should be blocked because QEMU should extract additional
vCPU state from KVM that should be migrated as part of vCPU VMState.
E.g. Whether vCPU is running in guest-mode or host-mode.

Fixes: d98f26073b ("target/i386: kvm: add VMX migration blocker")
Reviewed-by: Maran Wilson <maran.wilson@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20190619162140.133674-6-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-21 13:23:44 +02:00
Liran Alon bceeeef9e7 target/i386: kvm: Re-inject #DB to guest with updated DR6
If userspace (QEMU) debug guest, when #DB is raised in guest and
intercepted by KVM, KVM forwards information on #DB to userspace
instead of injecting #DB to guest.
While doing so, KVM don't update vCPU DR6 but instead report the #DB DR6
value to userspace for further handling.
See KVM's handle_exception() DB_VECTOR handler.

QEMU handler for this case is kvm_handle_debug(). This handler basically
checks if #DB is related to one of user set hardware breakpoints and if
not, it re-inject #DB into guest.
The re-injection is done by setting env->exception_injected to #DB which
will later be passed as events.exception.nr to KVM_SET_VCPU_EVENTS ioctl
by kvm_put_vcpu_events().

However, in case userspace re-injects #DB, KVM expects userspace to set
vCPU DR6 as reported to userspace when #DB was intercepted! Otherwise,
KVM_REQ_EVENT handler will inject #DB with wrong DR6 to guest.

Fix this issue by updating vCPU DR6 appropriately when re-inject #DB to
guest.

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20190619162140.133674-5-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-21 02:29:39 +02:00
Liran Alon 37936ac70f target/i386: kvm: Use symbolic constant for #DB/#BP exception constants
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20190619162140.133674-4-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-21 02:29:39 +02:00
Liran Alon b1115c9991 KVM: Introduce kvm_arch_destroy_vcpu()
Simiar to how kvm_init_vcpu() calls kvm_arch_init_vcpu() to perform
arch-dependent initialisation, introduce kvm_arch_destroy_vcpu()
to be called from kvm_destroy_vcpu() to perform arch-dependent
destruction.

This was added because some architectures (Such as i386)
currently do not free memory that it have allocated in
kvm_arch_init_vcpu().

Suggested-by: Maran Wilson <maran.wilson@oracle.com>
Reviewed-by: Maran Wilson <maran.wilson@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20190619162140.133674-3-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-21 02:29:39 +02:00
Liran Alon 6b2341eeea target/i386: kvm: Delete VMX migration blocker on vCPU init failure
Commit d98f26073b ("target/i386: kvm: add VMX migration blocker")
added migration blocker for vCPU exposed with Intel VMX because QEMU
doesn't yet contain code to support migration of nested virtualization
workloads.

However, that commit missed adding deletion of the migration blocker in
case init of vCPU failed. Similar to invtsc_mig_blocker. This commit fix
that issue.

Fixes: d98f26073b ("target/i386: kvm: add VMX migration blocker")
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Maran Wilson <maran.wilson@oracle.com>
Message-Id: <20190619162140.133674-2-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-21 02:29:39 +02:00
Liran Alon b3e89c941a vhost-scsi: Allow user to enable migration
In order to perform a valid migration of a vhost-scsi device,
the following requirements must be met:
(1) The virtio-scsi device state needs to be saved & loaded.
(2) The vhost backend must be stopped before virtio-scsi device state
is saved:
  (2.1) Sync vhost backend state to virtio-scsi device state.
  (2.2) No further I/O requests are made by vhost backend to target
        SCSI device.
  (2.3) No further guest memory access takes place after VM is stopped.
(3) Requests in-flight to target SCSI device are completed before
    migration handover.
(4) Target SCSI device state needs to be saved & loaded into the
    destination host target SCSI device.

Previous commit ("vhost-scsi: Add VMState descriptor")
add support to save & load the device state using VMState.
This meets requirement (1).

When VM is stopped by migration thread (On Pre-Copy complete), the
following code path is executed:
migration_completion() -> vm_stop_force_state() -> vm_stop() ->
do_vm_stop().

do_vm_stop() calls first pause_all_vcpus() which pause all guest
vCPUs and then call vm_state_notify().
In case of vhost-scsi device, this will lead to the following code path
to be executed:
vm_state_notify() -> virtio_vmstate_change() ->
virtio_set_status() -> vhost_scsi_set_status() -> vhost_scsi_stop().
vhost_scsi_stop() then calls vhost_scsi_clear_endpoint() and
vhost_scsi_common_stop().

vhost_scsi_clear_endpoint() sends VHOST_SCSI_CLEAR_ENDPOINT ioctl to
vhost backend which will reach kernel's vhost_scsi_clear_endpoint()
which process all pending I/O requests and wait for them to complete
(vhost_scsi_flush()). This meets requirement (3).

vhost_scsi_common_stop() will stop the vhost backend.
As part of this stop, dirty-bitmap is synced and vhost backend state is
synced with virtio-scsi device state. As at this point guest vCPUs are
already paused, this meets requirement (2).

At this point we are left with requirement (4) which is target SCSI
device specific and therefore cannot be done by QEMU. Which is the main
reason why vhost-scsi adds a migration blocker.
However, as this can be handled either by an external orchestrator or
by using shared-storage (i.e. iSCSI), there is no reason to limit the
orchestrator from being able to explictly specify it wish to enable
migration even when VM have a vhost-scsi device.

Considering all the above, this commit allows orchestrator to explictly
specify that it is responsbile for taking care of requirement (4) and
therefore vhost-scsi should not add a migration blocker.

Reviewed-by: Nir Weiner <nir.weiner@oracle.com>
Reviewed-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20190416125912.44001-4-liran.alon@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-06-02 21:32:06 -04:00
Liran Alon 5b8063c406 i386: Compile CPUX86State xsave_buf only when support KVM or HVF
While at it, also rename var to indicate it is not used only in KVM.

Reviewed-by: Nikita Leshchenko <nikita.leshchenko@oracle.com>
Reviewed-by: Patrick Colp <patrick.colp@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20180914003827.124570-2-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02 19:09:12 +02:00
Liran Alon e13713db5b KVM: x86: Add support for save/load MSR_SMI_COUNT
This MSR returns the number of #SMIs that occurred on
CPU since boot.

KVM commit 52797bf9a875 ("KVM: x86: Add emulation of MSR_SMI_COUNT")
introduced support for emulating this MSR.

This commit adds support for QEMU to save/load this
MSR for migration purposes.

Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-13 12:04:03 +01:00