This patch fixes bug with stopping and restarting replay
through monitor.
Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Message-Id: <20160926080815.6992.71818.stgit@PASHA-ISP>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch introduces vmstate for replay data structures.
It allows saving and loading vmstate while replaying.
Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Message-Id: <20160926080810.6992.68420.stgit@PASHA-ISP>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch moves replay static variables into the structure
to allow saving and loading them with savevm/loadvm.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Message-Id: <20160926080804.6992.87687.stgit@PASHA-ISP>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Set cpu->running without taking the cpu_list lock, only requiring it if
there is a concurrent exclusive section. This requires adding a new
field to CPUState, which records whether a running CPU is being counted
in pending_cpus.
When an exclusive section is started concurrently with cpu_exec_start,
cpu_exec_start can use the new field to determine if it has to wait for
the end of the exclusive section. Likewise, cpu_exec_end can use it to
see if start_exclusive is waiting for that CPU.
This a separate patch for easier bisection of issues.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use async_safe_run_on_cpu() to make tb_flush() thread safe. This is
possible now that code generation does not happen in the middle of
execution.
It can happen that multiple threads schedule a safe work to flush the
translation buffer. To keep statistics and debugging output sane, always
check if the translation buffer has already been flushed.
Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
[AJB: minor re-base fixes]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <1470158864-17651-13-git-send-email-alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It is not necessary to hold qemu_cpu_list_mutex throughout the
exclusive section, because no other exclusive section can run
while pending_cpus != 0.
exclusive_idle() is called in cpu_exec_start(), and that prevents
any CPUs created after start_exclusive() from entering cpu_exec()
during an exclusive section.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
No need to call exclusive_idle() from cpu_exec_end since it is done
immediately afterwards in cpu_exec_start. Any exclusive section could
run as soon as cpu_exec_end leaves, because cpu->running is false and the
mutex is not taken, so the call does not add any protection either.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
async_run_on_cpu is only called from the I/O thread, not from CPU threads,
so it doesn't make any difference. It will make a difference however
for async_safe_run_on_cpu.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This will serve as the base for async_safe_run_on_cpu. Because
start_exclusive uses CPU_FOREACH, merge exclusive_lock with
qemu_cpu_list_lock: together with a call to exclusive_idle (via
cpu_exec_start/end) in cpu_list_add, this protects exclusive work
against concurrent CPU addition and removal.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Make CPU work core functions common between system and user-mode
emulation. User-mode does not use run_on_cpu, so do not implement it.
Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <1470158864-17651-10-git-send-email-alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add a mutex for the CPU list to system emulation, as it will be used to
manage safe work. Abstract manipulation of the CPU list in new functions
cpu_list_add and cpu_list_remove.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Convert pthread_mutex_t and pthread_cond_t to QemuMutex and QemuCond.
This will allow to make some locks and conditional variables common
between user and system mode emulation.
Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <1470158864-17651-7-git-send-email-alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
To avoid possible confusion, rename flush_queued_work() to
process_queued_cpu_work().
Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <1470158864-17651-6-git-send-email-alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the code common between run_on_cpu() and async_run_on_cpu() into a
new function queue_work_on_cpu().
Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <1470158864-17651-4-git-send-email-alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CPUState is a fairly common pointer to pass to these helpers. This means
if you need other arguments for the async_run_on_cpu case you end up
having to do a g_malloc to stuff additional data into the routine. For
the current users this isn't a massive deal but for MTTCG this gets
cumbersome when the only other parameter is often an address.
This adds the typedef run_on_cpu_func for helper functions which has an
explicit CPUState * passed as the first parameter. All the users of
run_on_cpu and async_run_on_cpu have had their helpers updated to use
CPUState where available.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
[Sergey Fedorov:
- eliminate more CPUState in user data;
- remove unnecessary user data passing;
- fix target-s390x/kvm.c and target-s390x/misc_helper.c]
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au> (ppc parts)
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> (s390 parts)
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <1470158864-17651-3-git-send-email-alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This way, overriding CFLAGS on make command line keeps glib-cflags
and doesn't break the build.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20160925205748.6280-2-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Migrating a VM during reboot sometimes results in differences
between the source and destination in the SMRAM area.
This is because migration_bitmap_sync() only fetches from KVM
the dirty log of address_space_memory. SMRAM memory slots
are ignored and the modifications to SMRAM are not sent to the
destination.
Reported-by: He Rongguang <herongguang.he@huawei.com>
Reviewed-by: He Rongguang <herongguang.he@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
As discussed on the list [1], having a comment stating that this file
is "public domain" is arguably wrong and not legally binding. This patch
replaces that comment with a clear GPLv2+ license as proposed in [2].
[1] http://lists.nongnu.org/archive/html/qemu-devel/2016-09/msg06151.html
[2] http://lists.nongnu.org/archive/html/qemu-devel/2016-09/msg06217.html
Worth noting, compiler.h was originally created on 5c026320 by splitting
qemu-common.h. At the time, qemu-common.h was already GPLv2+.
Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Message-Id: <1474642971-11866-1-git-send-email-felipe@nutanix.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It's 2.8 now, and maybe it's time to switch IOAPIC default version to
0x20.
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1474608795-23058-1-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
x86 vIOMMUs still lack of a complete IOMMU notifier mechanism.
Before that is achieved, let's open a door for vhost DMAR support,
which only requires cache invalidations (UNMAP operations).
Meanwhile, convert hw_error() to error_report() and exit(1), to make
the error messages cleaner and obvious (no CPU registers will be dumped).
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1474606948-14391-4-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The new interface can be used to replace the old notify_started() and
notify_stopped(). Meanwhile it provides explicit flags so that IOMMUs
can know what kind of notifications it is requested for.
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1474606948-14391-3-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
IOMMU Notifier list is used for notifying IO address mapping changes.
Currently VFIO is the only user.
However it is possible that future consumer like vhost would like to
only listen to part of its notifications (e.g., cache invalidations).
This patch introduced IOMMUNotifier and IOMMUNotfierFlag bits for a
finer grained control of it.
IOMMUNotifier contains a bitfield for the notify consumer describing
what kind of notification it is interested in. Currently two kinds of
notifications are defined:
- IOMMU_NOTIFIER_MAP: for newly mapped entries (additions)
- IOMMU_NOTIFIER_UNMAP: for entries to be removed (cache invalidates)
When registering the IOMMU notifier, we need to specify one or multiple
types of messages to listen to.
When notifications are triggered, its type will be checked against the
notifier's type bits, and only notifiers with registered bits will be
notified.
(For any IOMMU implementation, an in-place mapping change should be
notified with an UNMAP followed by a MAP.)
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1474606948-14391-2-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add IVRS table for AMD IOMMU. Generate IVRS or DMAR
depending on emulated IOMMU.
Signed-off-by: David Kiarie <davidkiarie4@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Add AMD IOMMU emulaton to Qemu in addition to Intel IOMMU.
The IOMMU does basic translation, error checking and has a
minimal IOTLB implementation. This IOMMU bypassed the need
for target aborts by responding with IOMMU_NONE access rights
and exempts the region 0xfee00000-0xfeefffff from translation
as it is the q35 interrupt region.
We advertise features that are not yet implemented to please
the Linux IOMMU driver.
IOTLB aims at implementing commands on real IOMMUs which is
essential for debugging and may not offer any performance
benefits
Signed-off-by: David Kiarie <davidkiarie4@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Kiarie <davidkiarie4@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Introduce PCI macros from for use by AMD IOMMU
Signed-off-by: David Kiarie <davidkiarie4@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Stop processing the vring if virtqueue_get_head() fetches an
out-of-bounds head index.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
If the avail ring index is bogus virtqueue_num_heads() must return
-EINVAL.
The only caller is virtqueue_get_avail_bytes(). Return saying no bytes
are available when virtqueue_num_heads() fails.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Stop processing the vring if an avail ring index is invalid.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
The virtio code uses int, unsigned int, and uint16_t for virtqueue
indices. The uint16_t is used for the low-level descriptor layout in
virtio_ring.h while code that isn't concerned with descriptor layout can
use unsigned int.
Use of int is problematic because it can result in signed/unsigned
comparison and incompatible int*/unsigned int* pointer types.
Make the virtqueue_get_avail_bytes() 'i' variable unsigned int. This
eliminates the need to introduce casts and modify code further in the
patches that follow.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
If the vring is invalid, tell the caller no bytes are available and mark
the device broken.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Errors can occur during virtqueue_pop(), especially in
virtqueue_map_desc(). In order to handle this we must unmap iov[]
before returning NULL. The caller will consider the virtqueue empty and
the virtio_error() call will have marked the device broken.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Send a subsection if the vdev->broken flag is set. This allows live
migration of broken virtio devices.
The subsection is only sent if vdev->broken has been set. In most cases
the flag will be clear and no subsection will be sent.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
QEMU prints an error message and exits when the device enters an invalid
state. Terminating the process is heavy-handed. The guest may still be
able to function even if there is a bug in a virtio guest driver.
Moreover, exiting is a bug in nested virtualization where a nested guest
could DoS other nested guests by killing a pass-through virtio device.
I don't think this configuration is possible today but it is likely in
the future.
If the broken flag is set, do not process virtqueues or write back used
descriptors. The broken flag can be cleared again by resetting the
device.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Fix a single occurrence of a tab character in a file that otherwise uses
spaces for indentation.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
commit (14c985cff target-i386: present virtual L3 cache info for vcpus)
misplaced compat property putting it in new 2.8 machine type
which would effectively to disable feature until 2.9 is released.
Intent of commit probably should be to disable feature for 2.7
and older while allowing not yet released 2.8 to have feature
enabled by default.
Cc: qemu-stable@nongnu.org
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Since commit
bacc344c ("machine: add properties to compat_props incrementaly")
there is no need to chain per machine type compat macro.
Clean up places where it was done anyway so it will be
consistent and won't confuse contributors during addtion
of new machine types.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
virtio back end uses set of buffers to facilitate I/O operations.
If its size is too large, 'cpu_physical_memory_map' could return
a null address. This would result in a null dereference while
un-mapping descriptors. Add check to avoid it.
Reported-by: Qinghao Tang <luodalongde@gmail.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Check that qemu disconnects the backend that doesn't have the previously
acked features.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This test just checks that 2 virtio-net queues can be setup over
vhost-user and waits for them to be started.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Check early connection failure and resume.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
Block layer patches
# gpg: Signature made Fri 23 Sep 2016 12:59:46 BST
# gpg: using RSA key 0x7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6
* remotes/kevin/tags/for-upstream: (33 commits)
block: Remove BB interface from blockdev-add/del
qemu-iotests/141: Avoid blockdev-add with id
block: Avoid printing NULL string in error messages
qemu-iotests/139: Avoid blockdev-add with id
qemu-iotests/124: Avoid blockdev-add with id
qemu-iotests/118: Avoid blockdev-add with id
qemu-iotests/117: Avoid blockdev-add with id
qemu-iotests/087: Avoid blockdev-add with id
qemu-iotests/081: Avoid blockdev-add with id
qemu-iotests/071: Avoid blockdev-add with id
qemu-iotests/067: Avoid blockdev-add with id
qemu-iotests/041: Avoid blockdev-add with id
qemu-iotests/118: Test media change with qdev name
block: Accept device model name for block_set_io_throttle
block: Accept device model name for blockdev-change-medium
block: Accept device model name for eject
block: Accept device model name for x-blockdev-remove-medium
block: Accept device model name for x-blockdev-insert-medium
block: Accept device model name for blockdev-open/close-tray
qdev-monitor: Add blk_by_qdev_id()
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
