Postcopy detects accesses to pages that haven't been transferred yet
using userfaultfd, and it causes exceptions on pages that are 'not
present'.
Ballooning also causes pages to be marked as 'not present' when the
guest inflates the balloon.
Potentially a balloon could be inflated to discard pages that are
currently inflight during postcopy and that may be arriving at about
the same time.
To avoid this confusion, disable ballooning during postcopy.
When disabled we drop balloon requests from the guest. Since ballooning
is generally initiated by the host, the management system should avoid
initiating any balloon instructions to the guest during migration,
although it's not possible to know how long it would take a guest to
process a request made prior to the start of migration.
Guest initiated ballooning will not know if it's really freed a page
of host memory or not.
Queueing the requests until after migration would be nice, but is
non-trivial, since the set of inflate/deflate requests have to
be compared with the state of the page to know what the final
outcome is allowed to be.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Commit ef546f1275 ("virtio: add
feature checking helpers") introduced a helper __virtio_has_feature.
We don't want to use reserved identifiers, though, so let's
rename __virtio_has_feature to virtio_has_feature and virtio_has_feature
to virtio_vdev_has_feature.
Signed-off-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>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Excessive virtio_balloon inflation can cause invocation of OOM-killer,
when Linux is under severe memory pressure. Various mechanisms are
responsible for correct virtio_balloon memory management. Nevertheless it
is often the case that these control tools does not have enough time to
react on fast changing memory load. As a result OS runs out of memory and
invokes OOM-killer. The balancing of memory by use of the virtio balloon
should not cause the termination of processes while there are pages in the
balloon. Now there is no way for virtio balloon driver to free memory at
the last moment before some process get killed by OOM-killer.
This does not provide a security breach as balloon itself is running
inside Guest OS and is working in the cooperation with the host. Thus
some improvements from Guest side should be considered as normal.
To solve the problem, introduce a virtio_balloon callback which is
expected to be called from the oom notifier call chain in out_of_memory()
function. If virtio balloon could release some memory, it will make the
system return and retry the allocation that forced the out of memory
killer to run.
This behavior should be enabled if and only if appropriate feature bit
is set on the device. It is off by default.
This functionality was recently merged into vanilla Linux.
commit 5a10b7dbf904bfe01bb9fcc6298f7df09eed77d5
Author: Raushaniya Maksudova <rmaksudova@parallels.com>
Date: Mon Nov 10 09:36:29 2014 +1030
This patch adds respective control bits into QEMU. It introduces
deflate-on-oom option for balloon device which does the trick.
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Raushaniya Maksudova <rmaksudova@parallels.com>
CC: Anthony Liguori <aliguori@amazon.com>
CC: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: James Bottomley <JBottomley@Odin.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
This was missed during the conversion of feature bit manipulation.
Signed-off-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: Michael S. Tsirkin <mst@redhat.com>
Make features 64bit wide everywhere.
On migration a full 64bit guest_features field is sent if one of the
high bits is set, in addition to the lower 32bit guest_features field
which must stay for compatibility reasons. That way we send the lower
32 feature bits twice, but the code is simpler because we don't have
to split and compose the 64bit features into two 32bit fields.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This is in preparation for using alias property in virtio-balloon-pci
and virtio-balloon-ccw.
Signed-off-by: Shannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
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>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
A VM supports only one balloon device, but due to several changes
in infrastructure the error message got messed up when trying
to add a second device. Fix it.
Before this fix
Command-line:
qemu-qmp: -device virtio-balloon-pci,id=balloon0: Another balloon device already registered
qemu-qmp: -device virtio-balloon-pci,id=balloon0: Adding balloon handler failed
qemu-qmp: -device virtio-balloon-pci,id=balloon0: Device 'virtio-balloon-pci' could not be initialized
HMP:
Another balloon device already registered
Adding balloon handler failed
Device 'virtio-balloon-pci' could not be initialized
QMP:
{ "execute": "device_add", "arguments": { "driver": "virtio-balloon-pci", "id": "balloon0" } }
{
"error": {
"class": "GenericError",
"desc": "Adding balloon handler failed"
}
}
After this fix
Command-line:
qemu-qmp: -device virtio-balloon-pci,id=balloon0: Only one balloon device is supported
qemu-qmp: -device virtio-balloon-pci,id=balloon0: Device 'virtio-balloon-pci' could not be initialized
HMP:
(qemu) device_add virtio-balloon-pci,id=balloon0
Only one balloon device is supported
Device 'virtio-balloon-pci' could not be initialized
(qemu)
QMP:
{ "execute": "device_add",
"arguments": { "driver": "virtio-balloon-pci", "id": "balloon0" } }
{
"error": {
"class": "GenericError",
"desc": "Only one balloon device is supported"
}
}
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
A bunch of fixes all over the place.
All of ACPI refactoring has been merged.
Legacy pci commands have been dropped.
virtio header cleanup
initial patches from virtio-1.0 branch
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJU/CoXAAoJECgfDbjSjVRpX7EH/RMmgtsDO4wvqJu++lHvkB/q
kSaXZYTpJTo0i5JE7n2brwuXA4902tTg9g5TMUpGPh9Pt2QRg7RTgGC1vqZyOBos
MPw+4BO2v66S6qgX7bOf222z7r64cHTY7pLkQlrfD4usPlu2eusZ64UTW6Ru51fW
WF9E9aunbl+HnuCGq6Iez3sCLscTBJpU/lEr6oSyHhuq3aa0CjjraEeV0E/QcwJG
HTUeFymL8NFvlXZblsLI++VOv7Mxpi6yiCQ5XoKpFgGMvidwo41Aso6gB3ySGxOd
w8O3Nbu77Iw/StDRNCg/5/GapabMKh2bE4UCsYY5OS63ZtD0fl0CCblhzm/ZFPw=
=LY/j
-----END PGP SIGNATURE-----
Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging
pci, pc, virtio fixes and cleanups
A bunch of fixes all over the place.
All of ACPI refactoring has been merged.
Legacy pci commands have been dropped.
virtio header cleanup
initial patches from virtio-1.0 branch
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* remotes/mst/tags/for_upstream: (130 commits)
acpi: drop unused code
aml-build: comment fix
acpi-build: fix typo in comment
acpi: update generated files
vhost user:support vhost user nic for non msi guests
aml-build: fix build for glib < 2.22
acpi: update generated files
Makefile.target: binary depends on config-devices
acpi-test-data: update after pci rewrite
acpi, mem-hotplug: use PC_DIMM_SLOT_PROP in acpi_memory_plug_cb().
pci-hotplug-old: Has been dead for five major releases, bury
pci: Give a few helpers internal linkage
acpi: make build_*() routines static to aml-build.c
pc: acpi: remove not used anymore ssdt-[misc|pcihp].hex.generated blobs
pc: acpi-build: drop template patching and create PCI bus tree dynamically
tests: ACPI: update pc/SSDT.bridge due to new alg of PCI tree creation
pc: acpi-build: simplify PCI bus tree generation
tests: add ACPI blobs for qemu with bridge cases
tests: bios-tables-test: add support for testing bridges
tests: ACPI test blobs update due to PCI0._CRS changes
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Conflicts:
hw/pci/pci-hotplug-old.c
When do memory balloon, it takes the 'ram_size' as the VM's current ram size,
But 'ram_size' is the startup configured ram size, it does not take into
account the hotplugged memory.
As a result, the balloon result will be confused.
Steps to reproduce:
(1)Start VM: qemu -m size=1024,slots=4,maxmem=8G
(2)In VM: #free -m : 1024M
(3)qmp balloon 512M
(4)In VM: #free -m : 512M
(5)hotplug pc-dimm 1G
(6)In VM: #free -m : 1512M
(7)qmp balloon 256M
(8)In VM: #free -m :1256M
We expect the VM's available ram size to be 256M after 'qmp balloon 256M'
command, but VM's real available ram size is 1256M.
For "qmp balloon" is not performance critical code, we use function
'get_current_ram_size' to get VM's current ram size.
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Add a helper function for checking whether a bit is set in the guest
features for a vdev as well as one that works on a feature bit set.
Convert code that open-coded this: It cleans up the code and makes it
easier to extend the guest feature bits.
Signed-off-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>
Commit 1f9296b avoids "other kinds of overflow" by limiting the
polling interval to UINT_MAX. The computations to protect are done in
64 bits. This is indeed safe when unsigned is 32 bits, as it commonly
is. It isn't when unsigned is 64 bits. Purely theoretical; I'm not
aware of such a system. Limit it to UINT32_MAX instead.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
When a QMP client changes the polling interval time by setting
the guest-stats-polling-interval property, the interval value
is stored and manipulated as an int64_t variable.
However, the balloon_stats_change_timer() function, which is
used to set the actual timer with the interval value, takes
an int instead, causing an overflow for big interval values.
This commit fix this bug by changing balloon_stats_change_timer()
to take an int64_t and also it limits the polling interval value
to UINT_MAX to avoid other kinds of overflow.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
[ pass VirtIODevice * to memory accessors,
Greg Kurz <gkurz@linux.vnet.ibm.com> ]
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
In order to migrate virtio subsections, they should be streamed after
the device itself. We need the device specific code to be called from
the common migration code to achieve this. This patch introduces load
and save methods for this purpose.
Suggested-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
If the guest hasn't updated the stats yet, instead of returning
an error, return '-1' for the stats and '0' as 'last-update'.
This lets applications ignore this without parsing the error message.
Related libvirt patch and discussion:
https://www.redhat.com/archives/libvir-list/2014-May/msg00460.html
Tested against current upstream libvirt - stat reporting works and
it no longer logs errors when the stats are queried on domain startup.
(Note: libvirt doesn't use the last-update field for anything yet)
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
We commonly use the error API like this:
err = NULL;
foo(..., &err);
if (err) {
goto out;
}
bar(..., &err);
Every error source is checked separately. The second function is only
called when the first one succeeds. Both functions are free to pass
their argument to error_set(). Because error_set() asserts no error
has been set, this effectively means they must not be called with an
error set.
The qapi-generated code uses the error API differently:
// *errp was initialized to NULL somewhere up the call chain
frob(..., errp);
gnat(..., errp);
Errors accumulate in *errp: first error wins, subsequent errors get
dropped. To make this work, the second function does nothing when
called with an error set. Requires non-null errp, or else the second
function can't see the first one fail.
This usage has also bled into visitor tests, and two device model
object property getters rtc_get_date() and balloon_stats_get_all().
With the "accumulate" technique, you need fewer error checks in
callers, and buy that with an error check in every callee. Can be
nice.
However, mixing the two techniques is confusing. You can't use the
"accumulate" technique with functions designed for the "check
separately" technique. You can use the "check separately" technique
with functions designed for the "accumulate" technique, but then
error_set() can't catch you setting an error more than once.
Standardize on the "check separately" technique for now, because it's
overwhelmingly prevalent.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
When visit_start_struct() fails, visit_end_struct() must not be
called. rtc_get_date() and balloon_stats_all() call it anyway. As
far as I can tell, they're only used with the string output visitor,
which doesn't care. Fix them anyway.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Using error_is_set(ERRP) to find out whether a function failed is
either wrong, fragile, or unnecessarily opaque. It's wrong when ERRP
may be null, because errors go undetected when it is. It's fragile
when proving ERRP non-null involves a non-local argument. Else, it's
unnecessarily opaque (see commit 84d18f0).
I guess the error_is_set(errp) in the ObjectProperty set() methods are
merely fragile right now, because I can't find a call chain that
passes a null errp argument.
Make the code more robust and more obviously correct: receive the
error in a local variable, then propagate it through the parameter.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Rename qdev -> dev since that's what realize's argument is called by
convention. No need to keep more "qdev" around than necessary.
Avoid duplicate VIRTIO_DEVICE() cast.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This ensures hot-unplug is handled properly by the proxy, and avoids
leaking bus_name which is freed by virtio_device_exit.
Cc: qemu-stable@nongnu.org
Acked-by: Andreas Faerber <afaerber@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This is an autogenerated patch using scripts/switch-timer-api.
Switch the entire code base to using the new timer API.
Note this patch may introduce some line length issues.
Signed-off-by: Alex Bligh <alex@alex.org.uk>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The category will be used to sort the devices displayed in
the command line help.
Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com>
Message-id: 1375107465-25767-4-git-send-email-marcel.a@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
All these typos were found by codespell.
sould -> should
emperical -> empirical
intialization -> initialization
successfuly -> successfully
gaurantee -> guarantee
Fix also another error (before before) in the same context.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Add ref/unref calls at the following places:
- places where memory regions are stashed by a listener and
used outside the BQL (including in Xen or KVM).
- memory_region_find callsites
- creation of aliases and containers (only the aliased/contained
region gets a reference to avoid loops)
- around calls to del_subregion/add_subregion, where the region
could disappear after the first call
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
So far, the size of all regions passed to listeners could fit in 64 bits,
because artificial regions (containers and aliases) are eliminated by
the memory core, leaving only device regions which have reasonable sizes
An IOMMU however cannot be eliminated by the memory core, and may have
an artificial size, hence we may need 65 bits to represent its size.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This clean the init and the exit functions and rename virtio_common_cleanup
to virtio_cleanup.
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1366791683-5350-7-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This remove the function pointer in VirtIODevice, and use only
VirtioDeviceClass function pointer.
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1366791683-5350-5-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Because dev->actual is uint32_t, the expression 'dev->actual <<
VIRTIO_BALLOON_PFN_SHIFT' is truncated to 32 bits. This overflows when
dev->actual >= 1048576.
To reproduce:
1. Start a VM with a QMP socket and 5G of RAM
2. Connect to the QMP socket, negotiate capabilities and issue:
{ "execute":"balloon", "arguments": { "value": 1073741824 } }
3. Watch for BALLOON_CHANGE QMP events, the last one will incorretly be:
{ "timestamp": { "seconds": 1366228965, "microseconds": 245466 },
"event": "BALLOON_CHANGE", "data": { "actual": 5368709120 } }
To fix it this commit casts it to ram_addr_t, which is ram_size's type.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
