This avoids lock recursion when REPLAY_CLOCK is called inside the
timers spinlock.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

When migrate_add_blocker failed, the invtsc_mig_blocker is not
appended so no need to remove. This can save several instructions.
Signed-off-by: NLi Qiang <liq3ea@163.com>
Message-Id: <20181006091816.7659-1-liq3ea@163.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add testmodes for SynIC messages and events.  The message or event
connection setup / teardown is initiated by the guest via new control
codes written to the test device port.  Then the test connections bounce
the respective operations back to the guest, i.e. the incoming messages
are posted or the incoming events are signaled on the configured vCPUs.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add handling of POST_MESSAGE hypercall.  For that, add an interface to
regsiter a handler for the messages arrived from the guest on a
particular connection id (IOW set up a message connection in Hyper-V
speak).
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082217.29481-10-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

When setting up a notifier for Hyper-V event connection, try to use the
KVM-assisted one first, and fall back to userspace handling of the
hypercall if the kernel doesn't provide the requested feature.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082217.29481-9-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add handling of SIGNAL_EVENT hypercall.  For that, provide an interface
to associate an EventNotifier with an event connection number, so that
it's signaled when the SIGNAL_EVENT hypercall with the matching
connection ID is called by the guest.

Support for using KVM functionality for this will be added in a followup
patch.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082217.29481-8-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add infrastructure to signal SynIC event flags by atomically setting the
corresponding bit in the event flags page and firing a SINT if
necessary.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082217.29481-7-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add infrastructure to deliver SynIC messages to the SynIC message page.

Note that KVM may also want to deliver (SynIC timer) messages to the
same message slot.

The problem is that the access to a SynIC message slot is controlled by
the value of its .msg_type field which indicates if the slot is being
owned by the hypervisor (zero) or by the guest (non-zero).

This leaves no room for synchronizing multiple concurrent producers.

The simplest way to deal with this for both KVM and QEMU is to only
deliver messages in the vcpu thread.  KVM already does this; this patch
makes it for QEMU, too.

Specifically,

 - add a function for posting messages, which only copies the message
   into the staging buffer if its free, and schedules a work on the
   corresponding vcpu to actually deliver it to the guest slot;

 - instead of a sint ack callback, set up the sint route with a message
   status callback.  This function is called in a bh whenever there are
   updates to the message slot status: either the vcpu made definitive
   progress delivering the message from the staging buffer (succeeded or
   failed) or the guest issued EOM; the status is passed as an argument
   to the callback.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082217.29481-6-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Per Hyper-V spec, SynIC message and event flag pages are to be
implemented as so called overlay pages.  That is, they are owned by the
hypervisor and, when mapped into the guest physical address space,
overlay the guest physical pages such that

1) the overlaid guest page becomes invisible to the guest CPUs until the
   overlay page is turned off
2) the contents of the overlay page is preserved when it's turned off
   and back on, even at a different address; it's only zeroed at vcpu
   reset

This particular nature of SynIC message and event flag pages is ignored
in the current code, and guest physical pages are used directly instead.
This happens to (mostly) work because the actual guests seem not to
depend on the features listed above.

This patch implements those pages as the spec mandates.

Since the extra RAM regions, which introduce migration incompatibility,
are only added at SynIC object creation which only happens when
hyperv_synic_kvm_only == false, no extra compat logic is necessary.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082217.29481-5-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Certain configurations do not allow SynIC to be used in QEMU.  In
particular,

- when hyperv_vpindex is off, SINT routes can't be used as they refer to
  the destination vCPU by vp_index

- older KVM (which doesn't expose KVM_CAP_HYPERV_SYNIC2) zeroes out
  SynIC message and event pages on every msr load, breaking migration

OTOH in-KVM users of SynIC -- SynIC timers -- do work in those
configurations, and we shouldn't stop the guest from using them.

To cover both scenarios, introduce an X86CPU property that makes CPU
init code to skip creation of the SynIC object (and thus disables any
SynIC use in QEMU) but keeps the KVM part of the SynIC working.
The property is clear by default but is set via compat logic for older
machine types.

As a result, when hv_synic and a modern machine type are specified, QEMU
will refuse to run unless vp_index is on and the kernel is recent
enough.  OTOH with an older machine type QEMU will run fine with
hv_synic=on against an older kernel and/or without vp_index enabled but
will disallow the in-QEMU uses of SynIC (in e.g. VMBus).
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082217.29481-4-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Make Hyper-V SynIC a device which is attached as a child to a CPU.  For
now it only makes SynIC visibile in the qom hierarchy, and maintains its
internal fields in sync with the respecitve msrs of the parent cpu (the
fields will be used in followup patches).
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082217.29481-3-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Put a bit more consistency into handling KVM_CAP_HYPERV_SYNIC capability,
by checking its availability and determining the feasibility of hv-synic
property first, and enabling it later.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082217.29481-2-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This will allow to build slightly leaner QEMU that supports some HyperV
features of KVM (e.g. SynIC timers, PV spinlocks, APIC assists, etc.)
but nothing else on the QEMU side.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082041.29380-6-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Accumulate HYPERV config options in a dedicated file.  There are only
two so far; more will be added later.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082041.29380-5-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

A significant part of hyperv.c is not actually tied to x86, and can
be moved to hw/.

This will allow to maintain most of Hyper-V and VMBus
target-independent, and to avoid conflicts with inclusion of
arch-specific headers down the road in VMBus implementation.

Also this stuff can now be opt-out with CONFIG_HYPERV.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082041.29380-4-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Also make the inverse function, hyperv_find_vcpu, static as it's not
used outside hyperv.c

This paves the way to making hyperv.c built optionally.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082041.29380-3-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Some parts of the Hyper-V hypervisor-guest interface appear to be
target-independent, so move them into a proper header.

Not that Hyper-V ARM64 emulation is around the corner but it seems more
conveninent to have most of Hyper-V and VMBus target-independent, and
allows to avoid conflicts with inclusion of arch-specific headers down
the road in VMBus implementation.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921082041.29380-2-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

There's nothing kvm-specific in it so follow the suite and replace
"kvm_hv" prefix with "hyperv".
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921081836.29230-9-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Multiple entities (e.g. VMBus devices) can use the same SINT route.  To
make their lives easier in maintaining SINT route ownership, make it
reference-counted.  Adjust the respective API names accordingly.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921081836.29230-8-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Use X86CPU pointer to refer to the respective HvSintRoute instead of
vp_index.  This is more convenient and also paves the way for future
enhancements.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921081836.29230-7-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Make sint ack callback accept an opaque pointer, that is stored on
sint_route at creation time.

This allows for more convenient interaction with the callback.

Besides, nothing outside hyperv.c should need to know the layout of
HvSintRoute fields any more so its declaration can be removed from the
header.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921081836.29230-6-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

There's no point setting up an sint ack notifier if no callback is
specified.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921081836.29230-5-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921081836.29230-4-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921081836.29230-3-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Make hyperv_testdev slightly easier to follow and enhance in future.
For that, put the hyperv sint routes (wrapped in a helper structure) on
a linked list rather than a fixed-size array.  Besides, this way
HvSintRoute can be treated as an opaque structure, allowing for easier
refactoring of the core Hyper-V SynIC code in followup pathches.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921081836.29230-2-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

rerror=ignore was returning true from scsi_handle_rw_error but the callers were not
calling scsi_req_complete when rerror=ignore returns true (this is the correct thing
to do when true is returned after executing a passthrough command).  Fix this by
calling it in scsi_handle_rw_error.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

If a command fails with a sense that scsi_sense_buf_to_errno converts to
ECANCELED/EAGAIN/ENOTCONN or with a unit attention, scsi_req_complete is
called twice.  This caused a crash.
Reported-by: NWangguang <wang.guangA@h3c.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NLi Qiang <liq3ea@163.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

When [2] was fixed it was agreed that adding and calling post_plug()
callback after device_reset() was low risk approach to hotfix issue
right before release. So it was merged instead of moving already
existing plug() callback after device_reset() is called which would
be more risky and require all plug() callbacks audit.

Looking at the current plug() callbacks, it doesn't seem that moving
plug() callback after device_reset() is breaking anything, so here
goes agreed upon [3] proper fix which essentially reverts [1][2]
and moves plug() callback after device_reset().
This way devices always comes to plug() stage, after it's been fully
initialized (including being reset), which fixes race condition [2]
without need for an extra post_plug() callback.

 1. (25e89788 "qdev: add HotplugHandler->post_plug() callback")
 2. (8449bcf9 "virtio-scsi: fix hotplug ->reset() vs event race")
 3. https://www.mail-archive.com/qemu-devel@nongnu.org/msg549915.htmlSigned-off-by: NIgor Mammedov <imammedo@redhat.com>
Message-Id: <1539696820-273275-1-git-send-email-imammedo@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Tested-by: Pierre Morel<pmorel@linux.ibm.com>
Acked-by: Pierre Morel<pmorel@linux.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Return value of qemu_timedate_diff(), used for calculation offset in
QAPI 'RTC_CHANGE' event, restored to keep compatibility. Since it
wasn't documented that difference is relative to host clock
advancement, this change also adds important note to 'RTC_CHANGE'
event description to highlight established implementation specifics.
Signed-off-by: NArtem Pisarenko <artem.k.pisarenko@gmail.com>
Message-Id: <1fc12c77e8b7115d3842919a8b586d9cbe4efca6.1539846575.git.artem.k.pisarenko@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This makes all current "-rtc" option parameters combinations produce
fixed/unambiguous RTC timedate reference for hardware emulation
frontends.
It restores determinism of guest execution when used with clock=vm and
specified base <datetime> value.

Buglink: https://bugs.launchpad.net/qemu/+bug/1797033Signed-off-by: NArtem Pisarenko <artem.k.pisarenko@gmail.com>
Message-Id: <1d963c3e013dfedafa1f6edb9fb219b7e49e39da.1539846575.git.artem.k.pisarenko@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Improve code readability and prepare for fixing bug #1797033
Signed-off-by: NArtem Pisarenko <artem.k.pisarenko@gmail.com>
Message-Id: <9330a48899f997431a34460014886d118a7c0960.1539846575.git.artem.k.pisarenko@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Documentation describing -rtc option updated to better match current
implementation and highlight some important specifics.
Signed-off-by: NArtem Pisarenko <artem.k.pisarenko@gmail.com>
Message-Id: <1b245c6c0803d4bf11dcbf9eb32f34af8c2bd0b4.1539846575.git.artem.k.pisarenko@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

accel_init_machine sets *(acc->allowed) to true if acc->init_machine(ms)
succeeds. There's no need to have both hvf_allowed and hvf_disabled.
Signed-off-by: NRoman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20181018143051.48508-1-r.bolshakov@yadro.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

According to Intel(R)64 and IA-32 Architectures Software Developer's
Manual, the following one-byte registers should be fetched when REX
prefix is present (sorted by reg encoding index):
AL, CL, DL, BL, SPL, BPL, SIL, DIL, R8L - R15L

The first 8 are fetched if REX.R is zero, the last 8 if non-zero.

The following registers should be fetched for instructions without REX
prefix (also sorted by reg encoding index):
AL, CL, DL, BL, AH, CH, DH, BH

Current emulation code doesn't handle accesses to SPL, BPL, SIL, DIL
when REX is present, thefore an instruction 40883e "mov %dil,(%rsi)" is
decoded as "mov %bh,(%rsi)".

That caused an infinite loop in vp_reset:
https://lists.gnu.org/archive/html/qemu-devel/2018-10/msg03293.htmlSigned-off-by: NRoman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20181018134401.44471-1-r.bolshakov@yadro.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Hyper-V PV IPI support is merged to KVM, enable the feature in Qemu. When
enabled, this allows Windows guests to send IPIs to other vCPUs with a
single hypercall even when there are >64 vCPUs in the request.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20181009130853.6412-3-vkuznets@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

As QEMU becomes more multi-threaded and non-synchronized, checkpoints
move from thread to thread. And the event queue that processed at checkpoints
should belong to the same thread in both record and replay executions.
This patch disables asynchronous event processing at virtual clock
checkpoint, because it may be invoked in different threads at record and
replay. This patch is temporary fix until the checkpoints are completely
refactored.
Signed-off-by: NPavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Message-Id: <20181018063345.7433.11678.stgit@pasha-VirtualBox>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPeng Hao <peng.hao2@zte.com.cn>
Message-Id: <1539795177-21038-6-git-send-email-peng.hao2@zte.com.cn>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPeng Hao <peng.hao2@zte.com.cn>
Message-Id: <1539795177-21038-5-git-send-email-peng.hao2@zte.com.cn>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPeng Hao <peng.hao2@zte.com.cn>
Message-Id: <1539890353-30273-1-git-send-email-peng.hao2@zte.com.cn>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>