75e972dab5
As a rule, CPU internal state should never be updated when !cpu->kvm_vcpu_dirty (or the HAX equivalent). If that is done, then subsequent calls to cpu_synchronize_state() - usually safe and idempotent - will clobber state. However, we routinely do this during a loadvm or incoming migration. Usually this is called shortly after a reset, which will clear all the cpu dirty flags with cpu_synchronize_all_post_reset(). Nothing is expected to set the dirty flags again before the cpu state is loaded from the incoming stream. This means that it isn't safe to call cpu_synchronize_state() from a post_load handler, which is non-obvious and potentially inconvenient. We could cpu_synchronize_all_state() before the loadvm, but that would be overkill since a) we expect the state to already be synchronized from the reset and b) we expect to completely rewrite the state with a call to cpu_synchronize_all_post_init() at the end of qemu_loadvm_state(). To clear this up, this patch introduces cpu_synchronize_pre_loadvm() and associated helpers, which simply marks the cpu state as dirty without actually changing anything. i.e. it says we want to discard any existing KVM (or HAX) state and replace it with what we're going to load. Cc: Juan Quintela <quintela@redhat.com> Cc: Dave Gilbert <dgilbert@redhat.com> Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Juan Quintela <quintela@redhat.com> |
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audio | ||
backends | ||
block | ||
bsd-user | ||
chardev | ||
contrib | ||
crypto | ||
default-configs | ||
disas | ||
docs | ||
dtc@558cd81bdd | ||
fpu | ||
fsdev | ||
gdb-xml | ||
hw | ||
include | ||
io | ||
libdecnumber | ||
linux-headers | ||
linux-user | ||
migration | ||
nbd | ||
net | ||
pc-bios | ||
pixman@87eea99e44 | ||
po | ||
qapi | ||
qga | ||
qobject | ||
qom | ||
replay | ||
roms | ||
scripts | ||
slirp | ||
stubs | ||
target | ||
tcg | ||
tests | ||
trace | ||
ui | ||
util | ||
.dir-locals.el | ||
.exrc | ||
.gitignore | ||
.gitmodules | ||
.mailmap | ||
.shippable.yml | ||
.travis.yml | ||
accel.c | ||
arch_init.c | ||
atomic_template.h | ||
balloon.c | ||
block.c | ||
blockdev-nbd.c | ||
blockdev.c | ||
blockjob.c | ||
bootdevice.c | ||
bt-host.c | ||
bt-vhci.c | ||
Changelog | ||
CODING_STYLE | ||
configure | ||
COPYING | ||
COPYING.LIB | ||
cpu-exec-common.c | ||
cpu-exec.c | ||
cpus-common.c | ||
cpus.c | ||
cputlb.c | ||
device_tree.c | ||
device-hotplug.c | ||
disas.c | ||
dma-helpers.c | ||
dump.c | ||
exec.c | ||
gdbstub.c | ||
HACKING | ||
hax-stub.c | ||
hmp-commands-info.hx | ||
hmp-commands.hx | ||
hmp.c | ||
hmp.h | ||
ioport.c | ||
iothread.c | ||
kvm-all.c | ||
kvm-stub.c | ||
LICENSE | ||
MAINTAINERS | ||
Makefile | ||
Makefile.objs | ||
Makefile.target | ||
memory_ldst.inc.c | ||
memory_mapping.c | ||
memory.c | ||
module-common.c | ||
monitor.c | ||
numa.c | ||
os-posix.c | ||
os-win32.c | ||
qapi-schema.json | ||
qdev-monitor.c | ||
qdict-test-data.txt | ||
qemu-bridge-helper.c | ||
qemu-doc.texi | ||
qemu-ga.texi | ||
qemu-img-cmds.hx | ||
qemu-img.c | ||
qemu-img.texi | ||
qemu-io-cmds.c | ||
qemu-io.c | ||
qemu-nbd.c | ||
qemu-nbd.texi | ||
qemu-option-trace.texi | ||
qemu-options-wrapper.h | ||
qemu-options.h | ||
qemu-options.hx | ||
qemu-seccomp.c | ||
qemu-tech.texi | ||
qemu.nsi | ||
qemu.sasl | ||
qmp.c | ||
qtest.c | ||
README | ||
replication.c | ||
replication.h | ||
rules.mak | ||
softmmu_template.h | ||
tcg-runtime.c | ||
tci.c | ||
thunk.c | ||
tpm.c | ||
trace-events | ||
translate-all.c | ||
translate-all.h | ||
translate-common.c | ||
user-exec-stub.c | ||
user-exec.c | ||
VERSION | ||
version.rc | ||
vl.c |
QEMU README =========== QEMU is a generic and open source machine & userspace emulator and virtualizer. QEMU is capable of emulating a complete machine in software without any need for hardware virtualization support. By using dynamic translation, it achieves very good performance. QEMU can also integrate with the Xen and KVM hypervisors to provide emulated hardware while allowing the hypervisor to manage the CPU. With hypervisor support, QEMU can achieve near native performance for CPUs. When QEMU emulates CPUs directly it is capable of running operating systems made for one machine (e.g. an ARMv7 board) on a different machine (e.g. an x86_64 PC board). QEMU is also capable of providing userspace API virtualization for Linux and BSD kernel interfaces. This allows binaries compiled against one architecture ABI (e.g. the Linux PPC64 ABI) to be run on a host using a different architecture ABI (e.g. the Linux x86_64 ABI). This does not involve any hardware emulation, simply CPU and syscall emulation. QEMU aims to fit into a variety of use cases. It can be invoked directly by users wishing to have full control over its behaviour and settings. It also aims to facilitate integration into higher level management layers, by providing a stable command line interface and monitor API. It is commonly invoked indirectly via the libvirt library when using open source applications such as oVirt, OpenStack and virt-manager. QEMU as a whole is released under the GNU General Public License, version 2. For full licensing details, consult the LICENSE file. Building ======== QEMU is multi-platform software intended to be buildable on all modern Linux platforms, OS-X, Win32 (via the Mingw64 toolchain) and a variety of other UNIX targets. The simple steps to build QEMU are: mkdir build cd build ../configure make Additional information can also be found online via the QEMU website: http://qemu-project.org/Hosts/Linux http://qemu-project.org/Hosts/Mac http://qemu-project.org/Hosts/W32 Submitting patches ================== The QEMU source code is maintained under the GIT version control system. git clone git://git.qemu-project.org/qemu.git When submitting patches, the preferred approach is to use 'git format-patch' and/or 'git send-email' to format & send the mail to the qemu-devel@nongnu.org mailing list. All patches submitted must contain a 'Signed-off-by' line from the author. Patches should follow the guidelines set out in the HACKING and CODING_STYLE files. Additional information on submitting patches can be found online via the QEMU website http://qemu-project.org/Contribute/SubmitAPatch http://qemu-project.org/Contribute/TrivialPatches Bug reporting ============= The QEMU project uses Launchpad as its primary upstream bug tracker. Bugs found when running code built from QEMU git or upstream released sources should be reported via: https://bugs.launchpad.net/qemu/ If using QEMU via an operating system vendor pre-built binary package, it is preferable to report bugs to the vendor's own bug tracker first. If the bug is also known to affect latest upstream code, it can also be reported via launchpad. For additional information on bug reporting consult: http://qemu-project.org/Contribute/ReportABug Contact ======= The QEMU community can be contacted in a number of ways, with the two main methods being email and IRC - qemu-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/qemu-devel - #qemu on irc.oftc.net Information on additional methods of contacting the community can be found online via the QEMU website: http://qemu-project.org/Contribute/StartHere -- End