A guest could attempt to use an uninitialised VirtQueue object
or unset Vring.align leading to a arithmetic exception. Add check
to avoid it.
Reported-by: Zhangboxian <zhangboxian@huawei.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: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Since commit f1f9e6c5 "vhost: adapt vhost_verify_ring_mappings() to
virtio 1 ring layout", we check the mapping of each part (descriptor
table, available ring and used ring) of each virtqueue separately.
The checking of a part is done by the vhost_verify_ring_part_mapping()
function: it returns either 0 on success or a negative errno if the
part cannot be mapped at the same place.
Unfortunately, the vhost_verify_ring_mappings() function checks its
return value the other way round. It means that we either:
- only verify the descriptor table of the first virtqueue, and if it
is valid we ignore all the other mappings
- or ignore all broken mappings until we reach a valid one
ie, we only raise an error if all mappings are broken, and we consider
all mappings are valid otherwise (false success), which is obviously
wrong.
This patch ensures that vhost_verify_ring_mappings() only returns
success if ALL mappings are okay.
Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
When qemu is compiled without debug, the dump gdb python script can fail with:
Error occurred in Python command: No symbol "vmcoreinfo_find" in current context.
Because vmcoreinfo_find() is inlined and not exported.
Use the underlying object_resolve_path_type() to get the instance instead.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
vhost_virtqueue_stop() gets avail index value from the backend,
except if the backend is not responding.
It happens when the backend crashes, and in this case, internal
state of the virtio queue is inconsistent, making packets
to corrupt the vring state.
With a Linux guest, it results in following error message on
backend reconnection:
[ 22.444905] virtio_net virtio0: output.0:id 0 is not a head!
[ 22.446746] net enp0s3: Unexpected TXQ (0) queue failure: -5
[ 22.476360] net enp0s3: Unexpected TXQ (0) queue failure: -5
Fixes: 283e2c2adc ("net: virtio-net discards TX data after link down")
Cc: qemu-stable@nongnu.org
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
In case of backend crash, it is not possible to restore internal
avail index from the backend value as vhost_get_vring_base
callback fails.
This patch provides a new interface to restore internal avail index
from the vring used index, as done by some vhost-user backend on
reconnection.
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
According to SDM 10.11.1, only [19:12] bits of MSI address are
Destination ID, change the mask to avoid ambiguity for VT-d spec
has used the bit 4 to indicate a remappable interrupt request.
Signed-off-by: Chao Gao <chao.gao@intel.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The msr invalidation code (commits 993eb and 2360b) inverts all
bits except MSR_TGPR and MSR_HVB. On non PowerPC 601 processors
this leads to incorrect change of excp_prefix in hreg_store_msr()
function. The problem is that new msr value get multiplied by msr_mask
and inverted msr does not, thus values of MSR_EP bit in new msr value
and inverted msr are distinct, so that excp_prefix changes but should
not.
Signed-off-by: Kurban Mallachiev <mallachiev@ispras.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Migration of pseries is broken with TCG because
QEMU tries to restore KVM MMU state unconditionally.
The result is a SIGSEGV in kvm_vm_ioctl():
#0 kvm_vm_ioctl (s=0x0, type=-2146390353)
at qemu/accel/kvm/kvm-all.c:2032
#1 0x00000001003e3e2c in kvmppc_configure_v3_mmu (cpu=<optimized out>,
radix=<optimized out>, gtse=<optimized out>, proc_tbl=<optimized out>)
at qemu/target/ppc/kvm.c:396
#2 0x00000001002f8b88 in spapr_post_load (opaque=0x1019103c0,
version_id=<optimized out>) at qemu/hw/ppc/spapr.c:1578
#3 0x000000010059e4cc in vmstate_load_state (f=0x106230000,
vmsd=0x1009479e0 <vmstate_spapr>, opaque=0x1019103c0,
version_id=<optimized out>) at qemu/migration/vmstate.c:165
#4 0x00000001005987e0 in vmstate_load (f=<optimized out>, se=<optimized out>)
at qemu/migration/savevm.c:748
This patch fixes the problem by not calling the KVM function with the
TCG mode.
Fixes: d39c90f5f3 ("spapr: Fix migration of Radix guests")
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
DIV_ROUND_UP(st.st_size, BDRV_SECTOR_SIZE) was overflowing ret (int) if
st.st_size is greater than 1TB.
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Lieven <pl@kamp.de>
Message-id: 1511798407-31129-1-git-send-email-pl@kamp.de
Signed-off-by: Max Reitz <mreitz@redhat.com>
This reverts the effects of commit 4afeffc857 ("blockjob: do not allow
coroutine double entry or entry-after-completion", 2017-11-21)
This fixed the symptom of a bug rather than the root cause. Canceling the
wait on a sleeping blockjob coroutine is generally fine, we just need to
make it work correctly across AioContexts. To do so, use a QEMUTimer
that calls block_job_enter. Use a mutex to ensure that block_job_enter
synchronizes correctly with block_job_sleep_ns.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-By: Jeff Cody <jcody@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Hide the clearing of job->busy in a single function, and set it
in block_job_enter. This lets block_job_do_yield verify that
qemu_coroutine_enter is not used while job->busy = false.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-By: Jeff Cody <jcody@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
All callers are using QEMU_CLOCK_REALTIME, and it will not be possible to
support more than one clock when block_job_sleep_ns switches to a single
timer stored in the BlockJob struct.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Tested-By: Jeff Cody <jcody@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The .drained_begin/end callbacks can (directly or indirectly via
aio_poll()) cause block nodes to be removed or the current BdrvChild to
point to a different child node.
Use QLIST_FOREACH_SAFE() to make sure we don't access invalid
BlockDriverStates or accidentally continue iterating the parents of the
new child node instead of the node we actually came from.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Tested-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When destroying a block job in block_job_unref() we should remove it
from the job list before calling block_job_remove_all_bdrv().
This is because removing the BDSs can trigger an aio_poll() and wake
up other jobs that might attempt to use the block job list. If that
happens the job we're currently destroying should not be in that list
anymore.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Introduced in commit f37708f6b8 (2.10). The NBD spec says a client
can request export names up to 4096 bytes in length, even though
they should not expect success on names longer than 256. However,
qemu hard-codes the limit of 256, and fails to filter out a client
that probes for a longer name; the result is a stack smash that can
potentially give an attacker arbitrary control over the qemu
process.
The smash can be easily demonstrated with this client:
$ qemu-io f raw nbd://localhost:10809/$(printf %3000d 1 | tr ' ' a)
If the qemu NBD server binary (whether the standalone qemu-nbd, or
the builtin server of QMP nbd-server-start) was compiled with
-fstack-protector-strong, the ability to exploit the stack smash
into arbitrary execution is a lot more difficult (but still
theoretically possible to a determined attacker, perhaps in
combination with other CVEs). Still, crashing a running qemu (and
losing the VM) is bad enough, even if the attacker did not obtain
full execution control.
CC: qemu-stable@nongnu.org
Signed-off-by: Eric Blake <eblake@redhat.com>
The NBD spec gives us permission to abruptly disconnect on clients
that send outrageously large option requests, rather than having
to spend the time reading to the end of the option. No real
option request requires that much data anyways; and meanwhile, we
already have the practice of abruptly dropping the connection on
any client that sends NBD_CMD_WRITE with a payload larger than 32M.
For comparison, nbdkit drops the connection on any request with
more than 4096 bytes; however, that limit is probably too low
(as the NBD spec states an export name can theoretically be up
to 4096 bytes, which means a valid NBD_OPT_INFO could be even
longer) - even if qemu doesn't permit exports longer than 256
bytes.
It could be argued that a malicious client trying to get us to
read nearly 4G of data on a bad request is a form of denial of
service. In particular, if the server requires TLS, but a client
that does not know the TLS credentials sends any option (other
than NBD_OPT_STARTTLS or NBD_OPT_EXPORT_NAME) with a stated
payload of nearly 4G, then the server was keeping the connection
alive trying to read all the payload, tying up resources that it
would rather be spending on a client that can get past the TLS
handshake. Hence, this warranted a CVE.
Present since at least 2.5 when handling known options, and made
worse in 2.6 when fixing support for NBD_FLAG_C_FIXED_NEWSTYLE
to handle unknown options.
CC: qemu-stable@nongnu.org
Signed-off-by: Eric Blake <eblake@redhat.com>
If socket_listen_cleanup is passed an invalid FD, then querying the socket
local address will fail. We must thus be prepared for the returned addr to
be NULL
Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Version: GnuPG v1
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Merge remote-tracking branch 'remotes/jasowang/tags/net-pull-request' into staging
# gpg: Signature made Tue 28 Nov 2017 03:58:11 GMT
# gpg: using RSA key 0xEF04965B398D6211
# gpg: Good signature from "Jason Wang (Jason Wang on RedHat) <jasowang@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg: It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 215D 46F4 8246 689E C77F 3562 EF04 965B 398D 6211
* remotes/jasowang/tags/net-pull-request:
virtio-net: don't touch virtqueue if vm is stopped
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Guest state should not be touched if VM is stopped, unfortunately we
didn't check running state and tried to drain tx queue unconditionally
in virtio_net_set_status(). A crash was then noticed as a migration
destination when user type quit after virtqueue state is loaded but
before region cache is initialized. In this case,
virtio_net_drop_tx_queue_data() tries to access the uninitialized
region cache.
Fix this by only dropping tx queue data when vm is running.
Fixes: 283e2c2adc ("net: virtio-net discards TX data after link down")
Cc: Yuri Benditovich <yuri.benditovich@daynix.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: qemu-stable@nongnu.org
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
When you cancel an in-progress 'mirror' job (or "active `block-commit`")
with QMP `block-job-cancel`, it emits the event: BLOCK_JOB_CANCELLED.
However, when `block-job-cancel` is issued *after* `drive-mirror` has
indicated (via the event BLOCK_JOB_READY) that the source and
destination have reached synchronization:
[...] # Snip `drive-mirror` invocation & outputs
{
"execute":"block-job-cancel",
"arguments":{
"device":"virtio0"
}
}
{"return": {}}
It (`block-job-cancel`) will counterintuitively emit the event
'BLOCK_JOB_COMPLETED':
{
"timestamp":{
"seconds":1510678024,
"microseconds":526240
},
"event":"BLOCK_JOB_COMPLETED",
"data":{
"device":"virtio0",
"len":41126400,
"offset":41126400,
"speed":0,
"type":"mirror"
}
}
But this is expected behaviour, where the _COMPLETED event indicates
that synchronization has successfully ended (and the destination now has
a point-in-time copy, which is at the time of cancel).
So add a small note to this effect in 'block-core.json'. While at it,
also update the "Live disk synchronization -- drive-mirror and
blockdev-mirror" section in 'live-block-operations.rst'.
(Thanks: Max Reitz for reminding me of this caveat on IRC.)
Signed-off-by: Kashyap Chamarthy <kchamart@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This documents the image locking feature and explains when and how
related options can be used.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Both of these tests are for formats which now stipulate that they are
read-only. Adjust the tests to match.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Lukáš Doktor <ldoktor@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
cpu->compat_pvr is used to store the current compat mode of the cpu.
On the receiving side during incoming migration we check compatibility
with the compat mode by calling ppc_set_compat(). However we fail to set
the compat mode with the hypervisor since the "new" compat mode doesn't
differ from the current (due to a "cpu->compat_pvr != compat_pvr" check).
This means that kvm runs the vcpus without a compat mode, which is the
incorrect behaviour. The implication being that a compatibility mode
will never be in effect after migration.
To fix this so that the compat mode is correctly set with the
hypervisor, store the desired compat mode and reset cpu->compat_pvr to
zero before calling ppc_set_compat().
Fixes: 5dfaa532 ("ppc: fix ppc_set_compat() with KVM PR")
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The patb_entry is used to store the location of the process table in
guest memory. The msb is also used to indicate the mmu mode of the
guest, that is patb_entry & 1 << 63 ? radix_mode : hash_mode.
Currently we set this to zero in spapr_setup_hpt_and_vrma() since if
this function gets called then we know we're hash. However some code
paths, such as setting up the hpt on incoming migration of a hash guest,
call spapr_reallocate_hpt() directly bypassing this higher level
function. Since we assume radix if the host is capable this results in
the msb in patb_entry being left set so in spapr_post_load() we call
kvmppc_configure_v3_mmu() and tell the host we're radix which as
expected means addresses cannot be translated once we actually run the cpu.
To fix this move the zeroing of patb_entry into spapr_reallocate_hpt().
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
In our various supported host OSes, the time_t type may be either 32
or 64 bit, and could in theory also be either signed or unsigned.
Notably, in OpenBSD time_t is a 64 bit type even if 'long' is 32
bits, so using LONG_MAX for TIME_MAX is incorrect.
Use an approach suggested by Paolo Bonzini which calculates
the maximum value of the type rather than hardcoding it;
to do this we use the TYPE_MAXIMUM macro from Gnulib.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1511452598-6077-1-git-send-email-peter.maydell@linaro.org
We no longer support the old s390 transport, neither does the newest
Linux kernel. Remove it from the linux header script as well as the
s390x virtio code. We still should handle the VIRTIO_NOTIFY hypercall,
to tolerate early printk on older guest kernels without an sclp console.
We continue to ignore these events.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-Id: <20171115154223.109991-1-borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
OpenBSD/i386 uses elf_i386_obsd for the emulation linker.
Signed-off-by: Brad Smith <brad@comstyle.com>
Message-id: 20171107234608.GA395@humpty.home.comstyle.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
It was broken by commit 8ecc89f6e7 which
moved the SDL linker flags from macro libs_softmmu to macro SDL_LIBS.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Message-id: 20171116163732.31584-1-sw@weilnetz.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Commit 2726627197 started to use tb_unlock() and tlb_set_dirty() on
non TCG code. Add the functions as stubs, so that builds with TCG
disabled continue to compile.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
[PMM: tweaked commit message]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
When migrating a VM with 'migrate_set_capability postcopy-ram on'
a postcopy_state is set during the process, ending up with the
state POSTCOPY_INCOMING_END when the migration is over. This
postcopy_state is taken into account inside ram_load to check
how it will load the memory pages. This same ram_load is called when
in a loadvm command.
Inside ram_load, the logic to see if we're at postcopy_running state
is:
postcopy_running = postcopy_state_get() >= POSTCOPY_INCOMING_LISTENING
postcopy_state_get() returns this enum type:
typedef enum {
POSTCOPY_INCOMING_NONE = 0,
POSTCOPY_INCOMING_ADVISE,
POSTCOPY_INCOMING_DISCARD,
POSTCOPY_INCOMING_LISTENING,
POSTCOPY_INCOMING_RUNNING,
POSTCOPY_INCOMING_END
} PostcopyState;
In the case where ram_load is executed and postcopy_state is
POSTCOPY_INCOMING_END, postcopy_running will be set to 'true' and
ram_load will behave like a postcopy is in progress. This scenario isn't
achievable in a migration but it is reproducible when executing
savevm/loadvm after migrating with 'postcopy-ram on', causing loadvm
to fail with Error -22:
Source:
(qemu) migrate_set_capability postcopy-ram on
(qemu) migrate tcp:127.0.0.1:4444
Dest:
(qemu) migrate_set_capability postcopy-ram on
(qemu)
ubuntu1704-intel login:
Ubuntu 17.04 ubuntu1704-intel ttyS0
ubuntu1704-intel login: (qemu)
(qemu) savevm test1
(qemu) loadvm test1
Unknown combination of migration flags: 0x4 (postcopy mode)
error while loading state for instance 0x0 of device 'ram'
Error -22 while loading VM state
(qemu)
This patch fixes this problem by changing the existing logic for
postcopy_advised and postcopy_running in ram_load, making them
'false' if we're at POSTCOPY_INCOMING_END state.
Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reported-by: Balamuruhan S <bala24@linux.vnet.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Migration of a system under stress (for example, with
"stress-ng --numa 2") triggers on the destination
some kernel watchdog messages like:
NMI watchdog: BUG: soft lockup - CPU#0 stuck for 3489660870s!
NMI watchdog: BUG: soft lockup - CPU#1 stuck for 3489660884s!
This problem appears with the changes introduced by
42043e4 spapr: clock should count only if vm is running
I think this commit only triggers the problem.
Kernel computes the soft lockup duration using the
Virtual Timebase register (VTB), not using the Timebase
Register (TBR, the one 42043e4 stops).
It appears VTB is not migrated, so this patch adds it in
the list of the SPRs to migrate, and fixes the problem.
For the migration, I've tested a migration from qemu-2.8.0 and
pseries-2.8.0 to a patched master (qemu-2.11.0-rc1). The received
VTB is 0 (as is it not initialized by qemu-2.8.0), but the value
seems to be ignored by KVM and a non zero VTB is used by the kernel.
I have no explanation for that, but as the original problem appears
only with SMP system under stress I suspect some problems in KVM
(I think because VTB is shared by all threads of a core).
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The spapr-vty device implements the PAPR defined virtual console,
which is also implemented by IBM's proprietary PowerVM hypervisor.
PowerVM's implementation has a bug where it inserts an extra \0 after
every \r going to the guest. Because of that Linux's guest side
driver has a workaround which strips \0 characters that appear
immediately after a \r.
That means that when running under qemu, sending a binary stream from
host to guest via spapr-vty which happens to include a \r\0 sequence
will get corrupted by that workaround.
To deal with that, this patch duplicates PowerVM's bug, inserting an
extra \0 after each \r. Ugly, but the best option available.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
LUNs >= 256 have to be encoded with the so-called "flat space
addressing method" for virtio-scsi, where an additional bit has to
be set. SLOF already took care of this with the following commit:
https://git.qemu.org/?p=SLOF.git;a=commitdiff;h=f72a37713fea47da
(see https://bugzilla.redhat.com/show_bug.cgi?id=1431584 for details)
But QEMU does not use this encoding yet for device tree paths
that have to be handed over to SLOF to deal with the "bootindex"
property, so SLOF currently fails to boot from virtio-scsi devices
with LUNs >= 256 in the right boot order. Fix it by using the bit
to indicate the "flat space addressing method" for LUNs >= 256.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
When doing a live migration of a Xen guest with libxl, the images for
block devices are locked by the original QEMU process, and this prevent
the QEMU at the destination to take the lock and the migration fail.
>From QEMU point of view, once the RAM of a domain is migrated, there is
two QMP commands, "stop" then "xen-save-devices-state", at which point a
new QEMU is spawned at the destination.
Release locks in "xen-save-devices-state" so the destination can takes
them, if it's a live migration.
This patch add the "live" parameter to "xen-save-devices-state" which
default to true so older version of libxenlight can work with newer
version of QEMU.
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Add option to echo response to QMP / HMP command only on mismatch.
Useful for ignore all normal responses, but catching things like
segfaults.
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
The previous patch fixed a race condition, in which there were
coroutines being executing doubly, or after coroutine deletion.
We can detect common scenarios when this happens, and print an error
message and abort before we corrupt memory / data, or segfault.
This patch will abort if an attempt to enter a coroutine is made while
it is currently pending execution, either in a specific AioContext bh,
or pending execution via a timer. It will also abort if a coroutine
is scheduled, before a prior scheduled run has occurred.
We cannot rely on the existing co->caller check for recursive re-entry
to catch this, as the coroutine may run and exit with
COROUTINE_TERMINATE before the scheduled coroutine executes.
(This is the scenario that was occurring and fixed in the previous
patch).
This patch also re-orders the Coroutine struct elements in an attempt to
optimize caching.
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>