Background: s390x implements Low-Address Protection (LAP). If LAP is
enabled, writing to effective addresses (before any translation)
0-511 and 4096-4607 triggers a protection exception.
So we have subpage protection on the first two pages of every address
space (where the lowcore - the CPU private data resides).
By immediately invalidating the write entry but allowing the caller to
continue, we force every write access onto these first two pages into
the slow path. we will get a tlb fault with the specific accessed
addresses and can then evaluate if protection applies or not.
We have to make sure to ignore the invalid bit if tlb_fill() succeeds.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20171016202358.3633-2-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
These only depend on the host and therefore belong in the common
osdep, not in a target-dependent object.
While at it, query the host during an init constructor, which guarantees
the page size will be well-defined throughout the execution of the program.
Suggested-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In preparation for adding tc.size to be able to keep track of
TB's using the binary search tree implementation from glib.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
And fix the following warning when DEBUG_TB_INVALIDATE is enabled
in translate-all.c:
CC mipsn32-linux-user/accel/tcg/translate-all.o
/data/src/qemu/accel/tcg/translate-all.c: In function ‘tb_alloc_page’:
/data/src/qemu/accel/tcg/translate-all.c:1201:16: error: format ‘%lx’ expects argument of type ‘long unsigned int’, but argument 2 has type ‘tb_page_addr_t {aka unsigned int}’ [-Werror=format=]
printf("protecting code page: 0x" TARGET_FMT_lx "\n",
^
cc1: all warnings being treated as errors
/data/src/qemu/rules.mak:66: recipe for target 'accel/tcg/translate-all.o' failed
make[1]: *** [accel/tcg/translate-all.o] Error 1
Makefile:328: recipe for target 'subdir-mipsn32-linux-user' failed
make: *** [subdir-mipsn32-linux-user] Error 2
cota@flamenco:/data/src/qemu/build ((18f3fe1...) *$)$
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This gets rid of a hole in struct TranslationBlock.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Commit f0aff0f124 ("cputlb: add assert_cpu_is_self checks") buried
the increment of tlb_flush_count under TLB_DEBUG. This results in
"info jit" always (mis)reporting 0 TLB flushes when !TLB_DEBUG.
Besides, under MTTCG tlb_flush_count is updated by several threads,
so in order not to lose counts we'd either have to use atomic ops
or distribute the counter, which is more scalable.
This patch does the latter by embedding tlb_flush_count in CPUArchState.
The global count is then easily obtained by iterating over the CPU list.
Note that this change also requires updating the accessors to
tlb_flush_count to use atomic_read/set whenever there may be conflicting
accesses (as defined in C11) to it.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Since FlatViews are shared now and ASes not, this gets rid of
address_space_init_shareable().
This should cause no behavioural change.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20170921085110.25598-17-aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This adds a new "-d" switch to "info mtree" to print dispatch tree
internals.
This changes the way "-f" is handled - it prints now flat views and
associated address spaces.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20170921085110.25598-15-aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This renames some helpers to reflect better what they do.
This should cause no behavioural change.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20170921085110.25598-9-aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
As we are going to share FlatView's between AddressSpace's,
and AddressSpaceDispatch is a structure to perform quick lookup
in FlatView, this moves ASD to FlatView.
After previosly open coded ASD rendering, we can also remove
as->next_dispatch as the new FlatView pointer is stored
on a stack and set to an AS atomically.
flatview_destroy() is executed under RCU instead of
address_space_dispatch_free() now.
This makes mem_begin/mem_commit to work with ASD and mem_add with FV
as later on mem_add will be taking FV as an argument anyway.
This should cause no behavioural change.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20170921085110.25598-5-aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We are going to share FlatView's between AddressSpace's and per-AS
memory listeners won't suit the purpose anymore so open code
the dispatch tree rendering.
Since there is a good chance that dispatch_listener was the only
listener, this avoids address_space_update_topology_pass() if there is
no registered listeners; this should improve starting time.
This should cause no behavioural change.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20170921085110.25598-3-aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Replace the USE_DIRECT_JUMP ifdef with a TCG_TARGET_HAS_direct_jump
boolean test. Replace the tb_set_jmp_target1 ifdef with an unconditional
function tb_target_set_jmp_target.
While we're touching all backends, add a parameter for tb->tc_ptr;
we're going to need it shortly for some backends.
Move tb_set_jmp_target and tb_add_jump from exec-all.h to cpu-exec.c.
This opens the possibility for TCG_TARGET_HAS_direct_jump to be
a runtime decision -- based on host cpu capabilities, the size of
code_gen_buffer, or a future debugging switch.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-Id: <150002073981.22386.9870422422367410100.stgit@frigg.lan>
[rth: Moved max_insns adjustment from tb_start to init_disas_context.
Removed pc_next return from translate_insn.
Removed tcg_check_temp_count from generic loop.
Moved gen_io_end to exactly match gen_io_start.
Use qemu_log instead of error_report for temporary leaks.
Moved TB size/icount assignments before disas_log.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
Used later. An enum makes expected values explicit and
bounds the value space of switches.
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-Id: <150002049746.22386.2316077281615710615.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
This will allow some amount of cleanup to happen before
switching the backends over to enum DisasJumpType.
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Move the MemTxResult type to memattrs.h. We're going to want to
use it in cpu/qom.h, which doesn't want to include all of
memory.h. In practice MemTxResult and MemTxAttrs are pretty
closely linked since both are used for the new-style
read_with_attrs and write_with_attrs callbacks, so memattrs.h
is a reasonable home for this rather than creating a whole
new header file for it.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Needed to implement a target-agnostic gen_intermediate_code()
in the future.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-Id: <150002025498.22386.18051908483085660588.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
* new model of the ARM MPS2/MPS2+ FPGA based development board
* clean up DISAS_* exit conditions and fix various regressions
since commits e75449a3468a6b28c7b5 (in particular including
ones which broke OP-TEE guests)
* make Cortex-M3 and M4 correctly default to 8 PMSA regions
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Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20170717' into staging
target-arm queue:
* new model of the ARM MPS2/MPS2+ FPGA based development board
* clean up DISAS_* exit conditions and fix various regressions
since commits e75449a3468a6b28c7b5 (in particular including
ones which broke OP-TEE guests)
* make Cortex-M3 and M4 correctly default to 8 PMSA regions
# gpg: Signature made Mon 17 Jul 2017 13:43:45 BST
# gpg: using RSA key 0x3C2525ED14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg: aka "Peter Maydell <pmaydell@gmail.com>"
# gpg: aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83 15CF 3C25 25ED 1436 0CDE
* remotes/pmaydell/tags/pull-target-arm-20170717:
MAINTAINERS: Add entries for MPS2 board
hw/arm/mps2: Add ethernet
hw/arm/mps2: Add SCC
hw/misc/mps2_scc: Implement MPS2 Serial Communication Controller
hw/arm/mps2: Add timers
hw/char/cmsdk-apb-timer: Implement CMSDK APB timer device
hw/arm/mps2: Add UARTs
hw/char/cmsdk-apb-uart.c: Implement CMSDK APB UART
hw/arm/mps2: Implement skeleton mps2-an385 and mps2-an511 board models
target/arm: use DISAS_EXIT for eret handling
target/arm: use gen_goto_tb for ISB handling
target/arm/translate: ensure gen_goto_tb sets exit flags
target/arm/translate.h: expand comment on DISAS_EXIT
target/arm/translate: make DISAS_UPDATE match declared semantics
include/exec/exec-all: document common exit conditions
target/arm: Make Cortex-M3 and M4 default to 8 PMSA regions
qdev: support properties which don't set a default value
qdev-properties.h: Explicitly set the default value for arraylen properties
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
As a precursor to later patches attempt to come up with a more
concrete wording for what each of the common exit cases would be.
CC: Emilio G. Cota <cota@braap.org>
CC: Richard Henderson <rth@twiddle.net>
CC: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 20170713141928.25419-2-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Every vCPU now uses a separate set of TBs for each set of dynamic
tracing event state values. Each set of TBs can be used by any number of
vCPUs to maximize TB reuse when vCPUs have the same tracing state.
This feature is later used by tracetool to optimize tracing of guest
code events.
The maximum number of TB sets is defined as 2^E, where E is the number
of events that have the 'vcpu' property (their state is stored in
CPUState->trace_dstate).
For this to work, a change on the dynamic tracing state of a vCPU will
force it to flush its virtual TB cache (which is only indexed by
address), and fall back to the physical TB cache (which now contains the
vCPU's dynamic tracing state as part of the hashing function).
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-id: 149915775266.6295.10060144081246467690.stgit@frigg.lan
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Add new utility functions which both initialize a RAM
MemoryRegion and arrange for its contents to be migrated;
we give thes the memory_region_init_ram(), memory_region_init_rom()
and memory_region_init_rom_device() names that we just freed up
by renaming the old implementations to _nomigrate().
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1499438577-7674-6-git-send-email-peter.maydell@linaro.org
Rename memory_region_init_rom() to memory_region_init_rom_nomigrate()
and memory_region_init_rom_device() to
memory_region_init_rom_device_nomigrate().
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1499438577-7674-5-git-send-email-peter.maydell@linaro.org
Rename memory_region_init_ram() to memory_region_init_ram_nomigrate().
This leaves the way clear for us to provide a memory_region_init_ram()
which does handle migration.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1499438577-7674-4-git-send-email-peter.maydell@linaro.org
The various functions for initializing RAM MemoryRegions do not do
anything to cause the data in the MemoryRegion to be migrated.
Note in their documentation comments that this is the responsibility
of the caller.
(We will shortly add a new function that *does* do this for you.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1499438577-7674-3-git-send-email-peter.maydell@linaro.org
This finishes QOM'fication of IOMMUMemoryRegion by introducing
a IOMMUMemoryRegionClass. This also provides a fastpath analog for
IOMMU_MEMORY_REGION_GET_CLASS().
This makes IOMMUMemoryRegion an abstract class.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20170711035620.4232-3-aik@ozlabs.ru>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This defines new QOM object - IOMMUMemoryRegion - with MemoryRegion
as a parent.
This moves IOMMU-related fields from MR to IOMMU MR. However to avoid
dymanic QOM casting in fast path (address_space_translate, etc),
this adds an @is_iommu boolean flag to MR and provides new helper to
do simple cast to IOMMU MR - memory_region_get_iommu. The flag
is set in the instance init callback. This defines
memory_region_is_iommu as memory_region_get_iommu()!=NULL.
This switches MemoryRegion to IOMMUMemoryRegion in most places except
the ones where MemoryRegion may be an alias.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20170711035620.4232-2-aik@ozlabs.ru>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This is to make it clear the index is purely a gdbstub function and
should not be confused with the value of cpu->cpu_index. At the same
time we move the function from the header to gdbstub itself which will
help with later changes.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20170712105216.747-3-alex.bennee@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add CONFIG_TCG around TLB-related functions and structure declarations.
Some of these functions are defined in ./accel/tcg/cputlb.c, which will
not be linked in if TCG is disabled, and have no stubs; therefore, their
callers will also be compiled out for --disable-tcg.
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CONFIG_SOFTMMU should never be used in common code, so mark
it as poisoned, too.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1498454578-18709-6-git-send-email-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 1f5c00cfdb ("qom/cpu: move tlb_flush to cpu_common_reset")
moved the call to tlb_flush() from the target-specific reset handlers
into the common code qom/cpu.c file, and protected the call with
"#ifdef CONFIG_SOFTMMU" to avoid that it is called for linux-user
only targets. But since qom/cpu.c is common code, CONFIG_SOFTMMU is
*never* defined here, so the tlb_flush() was simply never executed
anymore. Fix it by introducing a wrapper for tlb_flush() in a file
that is re-compiled for each target, i.e. in translate-all.c.
Fixes: 1f5c00cfdb
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1498454578-18709-5-git-send-email-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CONFIG_KVM is only defined for target-specific code, so nobody should
use it by accident in common code. To avoid such subtle bugs,
CONFIG_KVM is now marked as poisoned in common code. The header
include/sysemu/kvm.h is somewhat special since it is included
all over the place from common code, too, so we need some extra
logic via "#ifdef NEED_CPU_H" here to make sure that we can
compile all files without problems.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1498454578-18709-4-git-send-email-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The defines of some *-linux-user targets were still missing.
Suggested-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1498454578-18709-2-git-send-email-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We are relying on cpu_env being defined as a global, yet most
targets (i.e. all but arm/a64) have it defined as a local variable.
Luckily all of them use the same "cpu_env" name, but really
compilation shouldn't break if the name of that local variable
changed.
Fix it by using tcg_ctx.tcg_env, which all targets set in their
translate_init function. This change also helps paving the way
for the upcoming "translation loop common to all targets" work.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1497639397-19453-3-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1497639397-19453-2-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
In cpu_physical_memory_sync_dirty_bitmap(rb, start, ...), the 2nd
argument 'start' is relative to the start of the ramblock 'rb'. When
it's used to access the dirty memory bitmap of ram_list (i.e.
ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION]->blocks[]), an offset to
the start of all RAM (i.e. rb->offset) should be added to it, which has
however been missed since c/s 6b6712efcc. For a ramblock of host memory
backend whose offset is not zero, cpu_physical_memory_sync_dirty_bitmap()
synchronizes the incorrect part of the dirty memory bitmap of ram_list
to the per ramblock dirty bitmap. As a result, a guest with host
memory backend may crash after migration.
Fix it by adding the offset of ramblock when accessing the dirty memory
bitmap of ram_list in cpu_physical_memory_sync_dirty_bitmap().
Reported-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Message-Id: <20170628083704.24997-1-haozhong.zhang@intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Tested-by: Juan Quintela <quintela@redhat.com>
Tested-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
This introduces a special callback which allows to run code from some MMIO
devices.
SysBusDevice with a MemoryRegion which implements the request_ptr callback will
be notified when the guest try to execute code from their offset. Then it will
be able to eg: pre-load some code from an SPI device or ask a pointer from an
external simulator, etc..
When the pointer or the data in it are no longer valid the device has to
invalidate it.
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Allocating an arbitrarily-sized array of tbs results in either
(a) a lot of memory wasted or (b) unnecessary flushes of the code
cache when we run out of TB structs in the array.
An obvious solution would be to just malloc a TB struct when needed,
and keep the TB array as an array of pointers (recall that tb_find_pc()
needs the TB array to run in O(log n)).
Perhaps a better solution, which is implemented in this patch, is to
allocate TB's right before the translated code they describe. This
results in some memory waste due to padding to have code and TBs in
separate cache lines--for instance, I measured 4.7% of padding in the
used portion of code_gen_buffer when booting aarch64 Linux on a
host with 64-byte cache lines. However, it can allow for optimizations
in some host architectures, since TCG backends could safely assume that
the TB and the corresponding translated code are very close to each
other in memory. See this message by rth for a detailed explanation:
https://lists.gnu.org/archive/html/qemu-devel/2017-03/msg05172.html
Subject: Re: GSoC 2017 Proposal: TCG performance enhancements
Message-ID: <1e67644b-4b30-887e-d329-1848e94c9484@twiddle.net>
Suggested-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1496790745-314-3-git-send-email-cota@braap.org>
[rth: Simplify the arithmetic in tcg_tb_alloc]
Signed-off-by: Richard Henderson <rth@twiddle.net>
These are defined in config-target.h and thus should never be
used in common code.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1497468113-2874-3-git-send-email-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Since we've got some new CPU targets in QEMU during the last months
and years, we've got some new TARGET_xxx defines now which should
be marked as poisoned for common code.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1497468113-2874-2-git-send-email-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>