Having the RAM creation code in a separate function is not
very helpful. Move this code directly inside the board_init()
function, this will later allow the board to have the QOM
ownership of the RAM.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20191021190653.9511-7-philmd@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The SDRAM is incorrectly created in the OMAP310 SoC.
Move its creation in the board code, this will later allow the
board to have the QOM ownership of the RAM.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20191021190653.9511-6-philmd@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The SDRAM is incorrectly created in the OMAP2420 SoC.
Move its creation in the board code, this will later allow the
board to have the QOM ownership of the RAM.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20191021190653.9511-5-philmd@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The SDRAM is incorrectly created in the SA1110 SoC.
Move its creation in the board code, this will later allow the
board to have the QOM ownership of the RAM.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20191021190653.9511-4-philmd@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
IEC binary prefixes ease code review: the unit is explicit.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20191021190653.9511-3-philmd@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
IEC binary prefixes ease code review: the unit is explicit.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20191021190653.9511-2-philmd@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The Exynos SoC has specific SDHCI registers. Use the s3c SDHCI
model which handle these specific registers.
This silents the following "SDHC ... not implemented" warnings so
we can focus on the important registers missing:
$ qemu-system-arm ... -d unimp \
-append "... root=/dev/mmcblk0 rootfstype=ext4 rw rootwait" \
-drive file=linux-build-test/rootfs/arm/rootfs-armv5.ext2,if=sd,format=raw
[...]
[ 25.744858] sdhci: Secure Digital Host Controller Interface driver
[ 25.745862] sdhci: Copyright(c) Pierre Ossman
[ 25.783188] s3c-sdhci 12530000.sdhci: clock source 2: mmc_busclk.2 (12000000 Hz)
SDHC rd_4b @0x80 not implemented
SDHC wr_4b @0x80 <- 0x00000020 not implemented
SDHC wr_4b @0x8c <- 0x00030000 not implemented
SDHC rd_4b @0x80 not implemented
SDHC wr_4b @0x80 <- 0xc0004100 not implemented
SDHC wr_4b @0x84 <- 0x80808080 not implemented
[ 26.013318] mmc0: SDHCI controller on samsung-hsmmc [12530000.sdhci] using ADMA
[ 26.032318] Synopsys Designware Multimedia Card Interface Driver
[ 42.024885] Waiting for root device /dev/mmcblk0...
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Message-id: 20191005154748.21718-5-f4bug@amsat.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This file keeps the various QDev blocks separated by comments.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20191005154748.21718-3-f4bug@amsat.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Switch the mcf5208 code away from bottom-half based ptimers to
the new transaction-based ptimer API. This just requires adding
begin/commit calls around the various places that modify the ptimer
state, and using the new ptimer_init() function to create the timer.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Thomas Huth <huth@tuxfamily.org>
Message-id: 20191017132905.5604-9-peter.maydell@linaro.org
Switch the etraxfs_timer code away from bottom-half based ptimers to
the new transaction-based ptimer API. This just requires adding
begin/commit calls around the various places that modify the ptimer
state, and using the new ptimer_init() function to create the timer.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20191017132905.5604-7-peter.maydell@linaro.org
Switch the altera_timer code away from bottom-half based ptimers to
the new transaction-based ptimer API. This just requires adding
begin/commit calls around the various places that modify the ptimer
state, and using the new ptimer_init() function to create the timer.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20191017132905.5604-6-peter.maydell@linaro.org
Switch the lm32_timer code away from bottom-half based ptimers to the
new transaction-based ptimer API. This just requires adding
begin/commit calls around the various places that modify the ptimer
state, and using the new ptimer_init() function to create the ytimer.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20191017132905.5604-4-peter.maydell@linaro.org
Switch the sh_timer code away from bottom-half based ptimers to the
new transaction-based ptimer API. This just requires adding
begin/commit calls around the various places that modify the ptimer
state, and using the new ptimer_init() function to create the timer.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20191017132905.5604-3-peter.maydell@linaro.org
Switch the puv3_ost code away from bottom-half based ptimers to the
new transaction-based ptimer API. This just requires adding
begin/commit calls around the various places that modify the ptimer
state, and using the new ptimer_init() function to create the timer.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20191017132905.5604-2-peter.maydell@linaro.org
In commit b01422622b we did an automated rename of the ptimer_init()
function to ptimer_init_with_bh(). Unfortunately this caught the
unrelated arm_mptimer_init() function. Undo that accidental
renaming.
Fixes: b01422622b
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20191017133331.5901-1-peter.maydell@linaro.org
When booting a recent Linux kernel, the qemu message "Timer with delta
zero, disabling" is seen, apparently because a ptimer is started before
being initialized. Fix the problem by initializing the offending ptimer
before starting it.
The bug is effectively harmless in the old QEMUBH setup
because the sequence of events is:
* the delta zero means the timer expires immediately
* ptimer_reload() arranges for exynos4210_gfrc_event() to be called
* ptimer_reload() notices the zero delta and disables the timer
* later, the QEMUBH runs, and exynos4210_gfrc_event() correctly
configures the timer and restarts it
In the new transaction based API the bug is still harmless,
but differences of when the callback function runs mean the
message is not printed any more:
* ptimer_run() does nothing as it's inside a transaction block
* ptimer_transaction_commit() sees it has work to do and
calls ptimer_reload()
* the zero delta means the timer expires immediately
* ptimer_reload() calls exynos4210_gfrc_event() directly
* exynos4210_gfrc_event() configures the timer
* the delta is no longer zero so ptimer_reload() doesn't complain
(the zero-delta test is after the trigger-callback in
the ptimer_reload() function)
Regardless, the behaviour here was not intentional, and we should
just program the ptimer correctly to start with.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20191018143149.9216-1-peter.maydell@linaro.org
[PMM: Expansion/clarification of the commit message:
the message is about a zero delta, not a zero period;
added detail to the commit message of the analysis of what
is happening and why the kernel boots even with the message;
added note that the message goes away with the new ptimer API]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The 32-bit product should be sign-extended, not zero-extended.
Fixes: ea96b37464
Reported-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Message-id: 20190912183058.17947-1-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Implement reconnect. To achieve this:
1. add new modes:
connecting-wait: means, that reconnecting is in progress, and there
were small number of reconnect attempts, so all requests are
waiting for the connection.
connecting-nowait: reconnecting is in progress, there were a lot of
attempts of reconnect, all requests will return errors.
two old modes are used too:
connected: normal state
quit: exiting after fatal error or on close
Possible transitions are:
* -> quit
connecting-* -> connected
connecting-wait -> connecting-nowait (transition is done after
reconnect-delay seconds in connecting-wait mode)
connected -> connecting-wait
2. Implement reconnect in connection_co. So, in connecting-* mode,
connection_co, tries to reconnect unlimited times.
3. Retry nbd queries on channel error, if we are in connecting-wait
state.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20191009084158.15614-3-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Introduce a function to gracefully wake a coroutine sleeping in
qemu_co_sleep_ns().
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20191009084158.15614-2-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
'savevm' was buggy as it considered all monitor-owned block device
nodes for snapshot. With the introduction of -blockdev, the common
usage made all nodes including protocol and backing file nodes be
monitor-owned and thus considered for snapshot.
This is a problem since the 'file' protocol nodes can't have internal
snapshots and it does not make sense to take snapshot of nodes
representing backing files.
This was fixed by commit 05f4aced65. Clients need to be able to
detect whether this fix is present.
Since savevm does not have an QMP alternative, add the feature for the
'human-monitor-command' backdoor which is used to call this command in
modern use.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191018081454.21369-6-armbru@redhat.com>
Commit 8aa3a33e44 "tests/qapi-schema: Test for good feature lists in
structs" neglected to cover documentation comments, and the previous
commit followed its example. Make up for them.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191018081454.21369-5-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191018081454.21369-4-armbru@redhat.com>
Similarly to features for struct types introduce the feature flags also
for commands. This will allow notifying management layers of fixes and
compatible changes in the behaviour of a command which may not be
detectable any other way.
The changes were heavily inspired by commit 6a8c0b5102.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191018081454.21369-3-armbru@redhat.com>
Command and event details are indented three spaces, everything else
four. Messed up in commit 156402e504. Use four spaces consistently.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Message-Id: <20191018081454.21369-2-armbru@redhat.com>
Commit fbf09a2fa4 "qapi: add 'ifcond' to visitor methods" brought back
the executable bits. Fix that. Drop the #! line for good measure.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20191018074345.24034-8-armbru@redhat.com>
The QAPI code generator clocks in at some 3100 SLOC in 8 source files.
Almost 60% of the code is in qapi/common.py. Split it into more
focused modules:
* Move QAPISchemaPragma and QAPISourceInfo to qapi/source.py.
* Move QAPIError and its sub-classes to qapi/error.py.
* Move QAPISchemaParser and QAPIDoc to parser.py. Use the opportunity
to put QAPISchemaParser first.
* Move check_expr() & friends to qapi/expr.py. Use the opportunity to
put the code into a more sensible order.
* Move QAPISchema & friends to qapi/schema.py
* Move QAPIGen and its sub-classes, ifcontext,
QAPISchemaModularCVisitor, and QAPISchemaModularCVisitor to qapi/gen.py
* Delete camel_case(), it's unused since commit e98859a9b9 "qapi:
Clean up after recent conversions to QAPISchemaVisitor"
A number of helper functions remain in qapi/common.py. I considered
moving the code generator helpers to qapi/gen.py, but decided not to.
Perhaps we should rewrite them as methods of QAPIGen some day.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20191018074345.24034-7-armbru@redhat.com>
[Add "# -*- coding: utf-8 -*-" lines]
Add a new "microvm" section under "X86 Machines" with the new files
related to this machine type.
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
microvm is a machine type inspired by Firecracker and constructed
after its machine model.
It's a minimalist machine type without PCI nor ACPI support, designed
for short-lived guests. microvm also establishes a baseline for
benchmarking and optimizing both QEMU and guest operating systems,
since it is optimized for both boot time and footprint.
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Document the new microvm machine type.
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
qboot is a minimalist x86 firmware for booting Linux kernels. It does
the mininum amount of work required for the task, and it's able to
boot both PVH images and bzImages without relying on option roms.
This characteristics make it an ideal companion for the microvm
machine type.
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
In apic_accept_pic_intr(), reject PIC interruptions if a i8259 PIC has
not been instantiated (isa_pic == NULL).
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
This allows to alter the contents of an already added item.
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
As a last step into splitting PCMachineState and deriving
X86MachineState from it, make the functions previously extracted from
pc.c to x86.c independent from PCMachineState, using X86MachineState
instead.
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Split up PCMachineState and PCMachineClass and derive X86MachineState
and X86MachineClass from them. This allows sharing code with non-PC
x86 machine types.
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Move x86 functions that will be shared between PC and non-PC machine
types to x86.c, along with their helpers.
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Follow checkpatch.pl recommendation and remove commented out code from
x86_load_linux().
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Follow checkpatch.pl recommendation and avoid an assignment in if
condition in x86_load_linux().
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Follow checkpatch.pl recommendation and replace the use of strtol with
qemu_strtoui in x86_load_linux().
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Fix code style issues detected by checkpatch.pl on functions that will
be moved out to x86.c.
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
The following functions are named *pc* but are not PC-machine specific
but generic to the X86 architecture, rename them:
load_linux -> x86_load_linux
pc_new_cpu -> x86_new_cpu
pc_cpus_init -> x86_cpus_init
pc_cpu_index_to_props -> x86_cpu_index_to_props
pc_get_default_cpu_node_id -> x86_get_default_cpu_node_id
pc_possible_cpu_arch_ids -> x86_possible_cpu_arch_ids
old_pc_system_rom_init -> x86_system_rom_init
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Put QOM and main struct definition in a separate header file, so it
can be accessed from other components.
Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
hw/mem/ is only included if CONFIG_MEM_DEVICE is true, so we need not
specify the condition again in hw/mem/Makefile.objs.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The %m format specifier is an extension from glibc - and when compiling
QEMU for NetBSD, the compiler correctly complains, e.g.:
/home/qemu/qemu-test.ELjfrQ/src/util/main-loop.c: In function 'sigfd_handler':
/home/qemu/qemu-test.ELjfrQ/src/util/main-loop.c:64:13: warning: %m is only
allowed in syslog(3) like functions [-Wformat=]
printf("read from sigfd returned %zd: %m\n", len);
^
Let's use g_strerror() here instead, which is an easy-to-use wrapper
around the thread-safe strerror_r() function.
While we're at it, also convert the "printf()" in main-loop.c into
the preferred "error_report()".
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20191018130716.25438-1-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Hyper-V TLFS specifies this enlightenment as:
"NoNonArchitecturalCoreSharing - Indicates that a virtual processor will never
share a physical core with another virtual processor, except for virtual
processors that are reported as sibling SMT threads. This can be used as an
optimization to avoid the performance overhead of STIBP".
However, STIBP is not the only implication. It was found that Hyper-V on
KVM doesn't pass MD_CLEAR bit to its guests if it doesn't see
NoNonArchitecturalCoreSharing bit.
KVM reports NoNonArchitecturalCoreSharing in KVM_GET_SUPPORTED_HV_CPUID to
indicate that SMT on the host is impossible (not supported of forcefully
disabled).
Implement NoNonArchitecturalCoreSharing support in QEMU as tristate:
'off' - the feature is disabled (default)
'on' - the feature is enabled. This is only safe if vCPUS are properly
pinned and correct topology is exposed. As CPU pinning is done outside
of QEMU the enablement decision will be made on a higher level.
'auto' - copy KVM setting. As during live migration SMT settings on the
source and destination host may differ this requires us to add a migration
blocker.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20191018163908.10246-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alexander Shopov <ash@kambanaria.org>
Message-Id: <20191019120534.27479-2-ash@kambanaria.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
commit 369b41359a broke timer interrupt
reinjection when there is no period change by the guest.
In that case, old_period is 0, which ends up zeroing irq_coalesced
(counter of reinjected interrupts).
The consequence is Windows 7 is unable to synchronize time via NTP.
Easily reproducible by playing a fullscreen video with cirrus and VNC.
Fix by not updating s->irq_coalesced when old_period is 0.
V2: reorganize code (Paolo Bonzini)
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Message-Id: <20191010123008.GA19158@amt.cnet>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>