Reading twice the same field could give the guest an attack of
opportunity. In the case of event->type, gcc could compile the switch
statement into a jump table, effectively ending up reading the type
field multiple times.
This is part of XSA-155.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
src is stored in shared memory and src->nr_segments is dereferenced
twice at the end of the function. If a compiler decides to compile this
into two separate memory accesses then the size limitation could be
bypassed.
Fix it by removing the double access to src->nr_segments.
This is part of XSA-155.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Unfortunately the OpenBSD pdksh does not like brackets inside
the right part of a ${variable+word} parameter expansion:
$ echo "${a+($b)}"
ksh: ${a+($b)}": bad substitution
though both bash and dash accept them. In any case this line
was causing odd output in the case where nettle is not present:
nettle no ()
(because if nettle is not present then $nettle will be "no",
not a null string or unset).
Rewrite it to just use an if.
This bug was originally introduced in becaeb726 and was present
in the 2.4.0 release.
Fixes: https://bugs.launchpad.net/qemu/+bug/1525682
Reported-by: Dmitrij D. Czarkoff
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1450105357-8516-1-git-send-email-peter.maydell@linaro.org
Add a QIOChannel subclass that is capable of performing I/O
to/from a memory buffer. This implementation does not attempt
to support concurrent readers & writers. It is designed for
serialized access where by a single thread at a time may write
data, seek and then read data back out.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add a QIOChannel subclass that is capable of performing I/O
to/from a separate process, via a pair of pipes. The command
can be used for unidirectional or bi-directional I/O.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add a QIOChannel subclass that can run the websocket protocol over
the top of another QIOChannel instance. This initial implementation
is only capable of acting as a websockets server. There is no support
for acting as a websockets client yet.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add a QIOChannel subclass that can run the TLS protocol over
the top of another QIOChannel instance. The object provides a
simplified API to perform the handshake when starting the TLS
session. The layering of TLS over the underlying channel does
not have to be setup immediately. It is possible to take an
existing QIOChannel that has done some handshake and then swap
in the QIOChannelTLS layer. This allows for use with protocols
which start TLS right away, and those which start plain text
and then negotiate TLS.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add a QIOChannel subclass that is capable of operating on things
that are files, such as plain files, pipes, character/block
devices, but notably not sockets.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Implement a QIOChannel subclass that supports sockets I/O.
The implementation is able to manage a single socket file
descriptor, whether a TCP/UNIX listener, TCP/UNIX connection,
or a UDP datagram. It provides APIs which can listen and
connect either asynchronously or synchronously. Since there
is no asynchronous DNS lookup API available, it uses the
QIOTask helper for spawning a background thread to ensure
non-blocking operation.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
A number of I/O operations need to be performed asynchronously
to avoid blocking the main loop. The caller of such APIs need
to provide a callback to be invoked on completion/error and
need access to the error, if any. The small QIOTask provides
a simple framework for dealing with such probes. The API
docs inline provide an outline of how this is to be used.
Some functions don't have the ability to run asynchronously
(eg getaddrinfo always blocks), so to facilitate their use,
the task class provides a mechanism to run a blocking
function in a thread, while triggering the completion
callback in the main event loop thread. This easily allows
any synchronous function to be made asynchronous, albeit
at the cost of spawning a thread.
In this series, the QIOTask class will be used for things like
the TLS handshake, the websockets handshake and TCP connect()
progress.
The concept of QIOTask is inspired by the GAsyncResult
interface / GTask class in the GIO libraries. The min
version requirements on glib don't allow those to be
used from QEMU, so QIOTask provides a facsimilie which
can be easily switched to GTask in the future if the
min version is increased.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
A number of the channel implementations will require the
ability to create watches on file descriptors / sockets.
To avoid duplicating this code in each channel, provide a
helper API for dealing with file descriptor watches.
There are two watch implementations provided. The first
is useful for bi-directional file descriptors such as
sockets, regular files, character devices, etc. The
second works with a pair of unidirectional file descriptors
such as pipes.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Start the new generic I/O channel framework by defining a
QIOChannel abstract base class. This is designed to feel
similar to GLib's GIOChannel, but with the addition of
support for using iovecs, qemu error reporting, file
descriptor passing, coroutine integration and use of
the QOM framework for easier sub-classing.
The intention is that anywhere in QEMU that almost
anywhere that deals with sockets will use this new I/O
infrastructure, so that it becomes trivial to then layer
in support for TLS encryption. This will at least include
the VNC server, char device backend and migration code.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
We model all the non-deprecated memory allocation functions from
https://developer.gnome.org/glib/stable/glib-Memory-Allocation.html
except for g_memdup(), g_clear_pointer(), g_steal_pointer(). We don't
use the latter two. Model the former.
Coverity now reports an OVERRUN
vl.c:2317: alloc_strlen: Allocating insufficient memory for the terminating null of the string.
Correct, but we omit the terminating null intentionally there.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1448901152-11716-1-git-send-email-armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In my testing, Coverity reported two more CHECKED_RETURN:
* qemu-char.c:1248: fixed in commit c1f2448: "qemu-char: retry g_poll
on EINTR".
* migration/qemu-file-unix.c:75: harmless, cleaned up in commit
4e39f57 "migration: Clean up use of g_poll() in
socket_writev_buffer()
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1450336833-27710-1-git-send-email-armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This was found by code inspection. If the request is cancelled twice,
the notifier is never called on the second cancellation request,
and hence for example a TMF might never finish.
All the calls in scsi_req_cancel_async are idempotent, so the change
is safe.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1450290827-30508-2-git-send-email-pbonzini@redhat.com>
This avoids calls to aio_poll without having acquired the context first.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1450290827-30508-1-git-send-email-pbonzini@redhat.com>
This commit fixes migration of a QEMU/KVM guest from kernel >= v3.9 to
kernel <= v3.7 (e.g. from RHEL 7 to RHEL 6). Without this commit a guest
migrated across these kernel versions fails to resume on the target host
as its segment descriptors are invalid.
Two separate kernel commits combined together to result in this bug:
commit f0495f9b9992f80f82b14306946444b287193390
Author: Avi Kivity <avi@redhat.com>
Date: Thu Jun 7 17:06:10 2012 +0300
KVM: VMX: Relax check on unusable segment
Some userspace (e.g. QEMU 1.1) munge the d and g bits of segment
descriptors, causing us not to recognize them as unusable segments
with emulate_invalid_guest_state=1. Relax the check by testing for
segment not present (a non-present segment cannot be usable).
Signed-off-by: Avi Kivity <avi@redhat.com>
commit 25391454e73e3156202264eb3c473825afe4bc94
Author: Gleb Natapov <gleb@redhat.com>
Date: Mon Jan 21 15:36:46 2013 +0200
KVM: VMX: don't clobber segment AR of unusable segments.
Usability is returned in unusable field, so not need to clobber entire
AR. Callers have to know how to deal with unusable segments already
since if emulate_invalid_guest_state=true AR is not zeroed.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
The first commit changed the KVM_SET_SREGS ioctl so that it did no treat
segment flags == 0 as an unusable segment, instead only looking at the
"present" flag.
The second commit changed KVM_GET_SREGS so that it did not clear the
flags of an unusable segment.
Since QEMU does not itself maintain the "unusable" flag across a
migration, the end result is that unusable segments read from a kernel
with these commits and loaded into a kernel without these commits are
not properly recognised as being unusable.
This commit updates both get_seg and set_seg so that the problem is
avoided even when migrating to or migrating from a QEMU without this
commit. In get_seg, we clear the segment flags if the segment is marked
unusable. In set_seg, we mark the segment unusable if the segment's
"present" flag is not set.
Signed-off-by: Michael Chapman <mike@very.puzzling.org>
Message-Id: <1449464047-17467-1-git-send-email-mike@very.puzzling.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
rcu_read_lock cannot change rcu_gp_ongoing from true to false
(the previous value of p_rcu_reader->ctr is zero), hence
there is no need to check p_rcu_reader->waiting and wake up
a concurrent synchronize_rcu.
While at it mark the wakeup as unlikely in rcu_read_unlock.
Reviewed-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1450265542-4323-1-git-send-email-pbonzini@redhat.com>
memcpy can take a large amount of time for small reads and writes.
Handle the common case of reading s/g descriptors from memory (there
is no corresponding "write" case that is as common, because writes
often use address_space_st* functions) by inlining the relevant
parts of address_space_read into the caller.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We want to inline the case where there is only one iteration, because
then the compiler can also inline the memcpy. As a start, extract
everything after the first address_space_translate call.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Rather than dispatching on is_write for every iteration, make
address_space_rw call one of the two functions. The amount of
duplicate logic is pretty small, and memory_access_is_direct can
be tweaked so that it inlines better in the callers.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
For the common case of DMA into non-hotplugged RAM, it is unnecessary
but expensive to do object_ref/unref. Add back an owner field to
MemoryRegion, so that these memory regions can skip the reference
counting.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Simplify the code and document the assumption. The only caller
that is not within rcu_read_lock is memory_region_get_ram_ptr.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
"Unimplemented" messages go to stderr, everything else goes to tracepoints
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Ensure that all log writes are protected by qemu_loglevel_mask or,
in serious cases, go to both the log and stderr.
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Avoid "naked" qemu_log, bring documentation for DEBUG #defines
up to date.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In some cases, the same message is printed both on stderr and in the log.
Avoid duplicate output in the default case where stderr _is_ the log,
and standardize this to stderr+log where it used to use stdio+log.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Our QA team wants to preserve serial output of the guest in between QEMU
runs to perform post-analysis.
By default this behavior is off (file is truncated each time QEMU is
started or device is plugged).
Signed-off-by: Olga Krishtal <okrishtal@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Eric Blake <eblake@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1449211324-17856-1-git-send-email-den@openvz.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch adds support for split IRQ chip mode. When
KVM_CAP_SPLIT_IRQCHIP is enabled:
1.) The PIC, PIT, and IOAPIC are implemented in userspace while
the LAPIC is implemented by KVM.
2.) The software IOAPIC delivers interrupts to the KVM LAPIC via
kvm_set_irq. Interrupt delivery is configured via the MSI routing
table, for which routes are reserved in target-i386/kvm.c then
configured in hw/intc/ioapic.c
3.) KVM delivers IOAPIC EOIs via a new exit KVM_EXIT_IOAPIC_EOI,
which is handled in target-i386/kvm.c and relayed to the software
IOAPIC via ioapic_eoi_broadcast.
Signed-off-by: Matt Gingell <gingell@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch adds the initial plumbing for split IRQ chip mode via
KVM_CAP_SPLIT_IRQCHIP. In addition to option processing, a number of
kvm_*_in_kernel macros are defined to help clarify which component is
where.
Signed-off-by: Matt Gingell <gingell@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Hyper-V SynIC timers are host timers that are configurable
by guest through corresponding MSR's (HV_X64_MSR_STIMER*).
Guest setup and use fired by host events(SynIC interrupt
and appropriate timer expiration message) as guest clock
events.
The state of Hyper-V SynIC timers are stored in corresponding
MSR's. This patch seria implements such MSR's support and migration.
Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Eduardo Habkost <ehabkost@redhat.com>
CC: "Andreas Färber" <afaerber@suse.de>
CC: Marcelo Tosatti <mtosatti@redhat.com>
CC: Denis V. Lunev <den@openvz.org>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: kvm@vger.kernel.org
Message-Id: <1448464885-8300-3-git-send-email-asmetanin@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
'hyperv-testdev' will be used by kvm-unit-tests
to setup Hyper-V SynIC SINT's routing and to inject
Hyper-V SynIC SINT's.
Hyper-V test device is ISA type device that creates 0x3000
IO memory region and catches write access into it. Every
write operation data decoded into ctl code and parameters
for Hyper-V test device.
Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Eduardo Habkost <ehabkost@redhat.com>
CC: "Andreas Färber" <afaerber@suse.de>
CC: Marcelo Tosatti <mtosatti@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch does Hyper-V Synthetic interrupt
controller(Hyper-V SynIC) MSR's support and
migration. Hyper-V SynIC is enabled by cpu's
'hv-synic' option.
This patch does not allow cpu creation if
'hv-synic' option specified but kernel
doesn't support Hyper-V SynIC.
Changes v3:
* removed 'msr_hv_synic_version' migration because
it's value always the same
* moved SynIC msr's initialization into kvm_arch_init_vcpu
Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Eduardo Habkost <ehabkost@redhat.com>
CC: "Andreas Färber" <afaerber@suse.de>
CC: Marcelo Tosatti <mtosatti@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Following the previous patch which changed pvscsi to be a pci express
device, this patch introduces a boolean property 'x-disable-pcie'.
Its default value is false, exposing pvscsi as a pcie device.
Setting 'x-disable-pcie' to 'on' preserves the old 'pci device' (non
express) behavior. This allows migration to older versions.
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@ravellosystems.com>
Message-Id: <1449994112-7054-7-git-send-email-shmulik.ladkani@ravellosystems.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Report the 'express endpoint' capability if on a PCIE bus.
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@ravellosystems.com>
Message-Id: <1449994112-7054-6-git-send-email-shmulik.ladkani@ravellosystems.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>