Mark 3270 as non-migratable for the experimental stage. Enable
the 3270 device so that we can use x3270 client to operate the guest.
Run qemu with the arguments:
-chardev socket,id=char3270_0,host=0.0.0.0,port=23,nowait,server,tn3270 \
-device x-terminal3270,chardev=char3270_0,devno=fe.0.000a,id=terminal3270_0 \
There are some restrictions for the first stage: We don't support SSL
connections, multiple client connections and client resizing. Only
tested with the x3270 client.
Signed-off-by: Jing Liu <liujbjl@linux.vnet.ibm.com>
Signed-off-by: Yang Chen <bjcyang@linux.vnet.ibm.com>
Reviewed-by: QingFeng Hao <haoqf@linux.vnet.ibm.com>
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
To ensure that we do not keep any 3270 sockets where the client is not
connected anymore, we send a packet with the timing mark option after
ten minutes of client inactivity. If the client does not answer it,
then the socket will be closed automatically.
This helps to ensure that there is no half-open situation on the 3270
socket.
Signed-off-by: Jing Liu <liujbjl@linux.vnet.ibm.com>
Reviewed-by: QingFeng Hao <haoqf@linux.vnet.ibm.com>
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
This introduces a chr_event handler to handle the 3270 connection
and disconnection events.
Signed-off-by: Jing Liu <liujbjl@linux.vnet.ibm.com>
Reviewed-by: QingFeng Hao <haoqf@linux.vnet.ibm.com>
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
This introduces the input and output handlers for 3270 device, setting
up the data tunnel among guest kernel, qemu and the 3270 client.
After the client connected and TN3270 handshake done, signal the not-ready
to ready status by an unsolicited device-end interrupt, and then the 3270
data stream could be handled correctly between the channel and socket.
Multiple commands generated by "Reset" key on x3270 are not supported now,
just simply terminate the connection.
Signed-off-by: Jing Liu <liujbjl@linux.vnet.ibm.com>
Signed-off-by: Yang Chen <bjcyang@linux.vnet.ibm.com>
Reviewed-by: QingFeng Hao <haoqf@linux.vnet.ibm.com>
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
This is a basic implementation of the emulated ccw-attached 3270
called x-terminal3270, which provides visibility of the device in
the qemu monitor and guest. The x prefix indicates that this is
just an experimental implementation for the current stage. This
device will not be compiled until the basic functions are available.
Signed-off-by: Yang Chen <bjcyang@linux.vnet.ibm.com>
Signed-off-by: Jing Liu <liujbjl@linux.vnet.ibm.com>
Reviewed-by: QingFeng Hao <haoqf@linux.vnet.ibm.com>
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
The static array exynos4210_uart_regs with register values is not
modified so it can be made const.
Few other functions accept driver or uart state as an argument but they
do not change it and do not cast it so this can be made const for code
safeness.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Message-id: 20170313184750.429-3-krzk@kernel.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Change Makefile.objs to use CONFIG_XEN instead of CONFIG_XEN_BACKEND, so
that the Xen backends are only built for targets that support Xen.
Set CONFIG_XEN in the toplevel Makefile to ensure that files that are
built only once pick up Xen support properly.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
Tested-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
CC: pbonzini@redhat.com
CC: peter.maydell@linaro.org
CC: rth@twiddle.net
CC: stefanha@redhat.com
Message-Id: <1489694518-16978-1-git-send-email-sstabellini@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Amit Shah <amit@kernel.org>
Use type_init() etc. to adapt the ColdFire UART
to the latest QEMU device conventions.
Signed-off-by: Thomas Huth <huth@tuxfamily.org>
Message-Id: <1485586582-6490-1-git-send-email-huth@tuxfamily.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The member VMStateField.start is used for two things, partial data
migration for VBUFFER data (basically provide migration for a
sub-buffer) and for locating next in QTAILQ.
The implementation of the VBUFFER feature is broken when VMSTATE_ALLOC
is used. This however goes unnoticed because actually partial migration
for VBUFFER is not used at all.
Let's consolidate the usage of VMStateField.start by removing support
for partial migration for VBUFFER.
Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Message-Id: <20170203175217.45562-1-pasic@linux.vnet.ibm.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
At present, the core device model code for 8250-like serial ports
(serial.c) and the code for serial ports attached to ISA-style legacy IO
(serial-isa.c) are both controlled by the CONFIG_SERIAL variable.
There are lots and lots of embedded platforms that have 8250-like serial
ports but have never had anything resembling ISA legacy IO. Therefore,
split serial-isa into its own CONFIG_SERIAL_ISA option so it can be
disabled for platforms where it's not appropriate.
For now, I enabled CONFIG_SERIAL_ISA in every default-config where
CONFIG_SERIAL is enabled, excepting microblaze, or32, and xtensa. As best
as I can tell, those platforms never used legacy ISA, and also don't
include PCI support (which would allow connection of a PCI->ISA bridge
and/or a southbridge including legacy ISA serial ports).
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Pick a uniform chardev type name.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The frame_size local variable in exynos4210_uart_update_parameters()
is calculated but never used (and has been this way since the
device was introduced in commit e5a4914efc). The qemu_chr_fe_ioctl()
doesn't need this information (if it really wanted it it could
calculate it from the parity/data_bits/stop_bits), so just drop
the variable entirely.
Fixes: https://bugs.launchpad.net/bugs/1655702
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1484589515-26353-1-git-send-email-peter.maydell@linaro.org
The serial_exit_core function doesn't free some resources.
This can lead memory leak when hotplug and unplug. This
patch avoid this.
Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Message-Id: <586cb5ab.f31d9d0a.38ac3.acf2@mx.google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, all virtio devices bypass IOMMU completely. This is because
address_space_memory is assumed and used during DMA emulation. This
patch converts the virtio core API to use DMA API. This idea is
- introducing a new transport specific helper to query the dma address
space. (only pci version is implemented).
- query and use this address space during virtio device guest memory
accessing when iommu platform (VIRTIO_F_IOMMU_PLATFORM) was enabled
for this device.
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Amit Shah <amit.shah@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-block@nongnu.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Drop the old Sysbus init and use instance_init and
DeviceClass::realize instead
Signed-off-by: xiaoqiang zhao <zxq_yx_007@163.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
When register Rcvr_timeout_reg0 (R_RTOR in cadence_uart.c) is set to
0, the receiver timeout counter should be disabled. See page 1801 of
"Zynq-7000 AP SoC Technical Reference Manual". This commit adds a
such a check before setting the receive timeout interrupt.
Signed-off-by: Andrew Gacek <andrew.gacek@gmail.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The Cadence UART device emulator calculates speed by dividing the
baud rate by a 'baud rate generator' & 'baud rate divider' value.
The device specification defines these register values to be
non-zero and within certain limits. Checks were recently added when
writing to these registers but not when restoring from migration.
This patch adds checks when restoring from migration to avoid divide by
zero errors.
Reported-by: Huawei PSIRT <psirt@huawei.com>
Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Message-id: 04ae30ed8ee1758cd2d2af880da4d28f74c67738.1481132150.git.alistair.francis@xilinx.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The can_receive() callbacks of the character devices should return
the amount of characters that can be accepted at once, not just a
boolean value (which rather means only one character at a time).
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
When using the serial console in the GTK interface of QEMU (and
QEMU has been compiled with CONFIG_VTE), it is possible to trigger
the assert() statement in vty_receive() in spapr_vty.c by pasting
a chunk of text with length > 16 into the QEMU window.
Most of the other serial backends seem to simply drop characters
that they can not handle, so I think we should also do the same in
spapr-vty to fix this issue.
Buglink: https://bugs.launchpad.net/qemu/+bug/1639322
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The Cadence UART device emulator calculates speed by dividing the
baud rate by a 'baud rate generator' & 'baud rate divider' value.
The device specification defines these register values to be
non-zero and within certain limits. Add checks for these limits
to avoid errors like divide by zero.
Reported-by: Huawei PSIRT <psirt@huawei.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Message-id: 1477596278-1470-1-git-send-email-ppandit@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Prepare xen_be_send_notify to be shared with frontends:
* xen_be_send_notify -> xen_pv_send_notify
Signed-off-by: Emil Condrea <emilcondrea@gmail.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Quan Xu <xuquan8@huawei.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Prepare xen_be_unbind_evtchn to be shared with frontends:
* xen_be_unbind_evtchn -> xen_pv_unbind_evtchn
Signed-off-by: Emil Condrea <emilcondrea@gmail.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Quan Xu <xuquan8@huawei.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Prepare xen_be_printf to be used by both backend and frontends:
* xen_be_printf -> xen_pv_printf
Signed-off-by: Emil Condrea <emilcondrea@gmail.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Quan Xu <xuquan8@huawei.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Fixes:
* WARNING: line over 80 characters
Signed-off-by: Emil Condrea <emilcondrea@gmail.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Quan Xu <xuquan8@huawei.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Fixes the following errors:
* ERROR: line over 90 characters
* ERROR: code indent should never use tabs
* ERROR: space prohibited after that open square bracket '['
* ERROR: do not initialise statics to 0 or NULL
* ERROR: "(foo*)" should be "(foo *)"
Signed-off-by: Emil Condrea <emilcondrea@gmail.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Quan Xu <xuquan8@huawei.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
The Cadence UART device emulator stores 'baud rate generator'
and 'baud rate divider' values, used in computing speed, in two
registers. The device specification defines their range and
their reset value. Use their correct value when resetting the
device in cadence_uart_reset.
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Message-id: 1477378140-2670-1-git-send-email-ppandit@redhat.com
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
No need to keep explicit_fe_open around if it affects only a
qemu_chr_fe_set_handlers(). Use an additional argument instead.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-24-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In most cases, front ends do not care about the side effect of
CharBackend, so we can simply skip the checks and call the qemu_chr_fe
functions even without associated CharDriver.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-20-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Now that all front end use qemu_chr_fe_init(), we can move chardev
claiming in init(), and add a function deinit() to release the chardev
and cleanup handlers.
The qemu_chr_fe_claim_no_fail() for property are gone, since the
property will raise an error instead. In other cases, where there is
already an error path, an error is raised instead. Finally, other cases
are handled by &error_abort in qemu_chr_fe_init().
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-19-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This also switches from qemu_chr_add_handlers() to
qemu_chr_fe_set_handlers(). Note that qemu_chr_fe_set_handlers() now
takes the focus when fe_open (qemu_chr_add_handlers() did take the
focus)
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-16-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
qemu_chr_accept_input() and qemu_chr_disconnect() are only used by
frontend, so use qemu_chr_fe prefix.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-14-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Similar to previous change, for the remaining CharDriverState front ends
users.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-13-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Store the property in a CharBackend instead of CharDriverState*. This
also replace systematically chr by chr.chr to access the
CharDriverState*. The following patches will replace it with calls to
qemu_chr_fe CharBackend functions.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-12-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The CharDriverState.init() callback is no longer set since commit
a61ae7f88c and thus unused. The only user, the malta FGPA display has
been converted to use an event "opened" callback instead.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-7-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Since commit b6607a1a20, serial_hds_isa_init() was introduced to
factor out serial_isa_init() loops. However, sun4uv shouldn't start from
0 when there is a mm serial on 0 already. Add a "from" argument to
serial_hds_isa_init().
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-5-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
16550A UART device uses an oscillator to generate frequencies
(baud base), which decide communication speed. This speed could
be changed by dividing it by a divider. If the divider is
greater than the baud base, speed is set to zero, leading to a
divide by zero error. Add check to avoid it.
Reported-by: Huawei PSIRT <psirt@huawei.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Message-Id: <1476251888-20238-1-git-send-email-ppandit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Now all the usages of the old version of VMSTATE_VIRTIO_DEVICE are gone,
so we can get rid of the conditionals, and the old macro.
Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Use the new VMSTATE_VIRTIO_DEVICE macro.
Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Ports enter a "throttled" state when writing to the chardev would block.
The current output VirtQueueElement is kept around until the chardev
becomes writable again.
There are several places in the virtio-serial lifecycle where the
VirtQueueElement should be thrown away. For example, if the virtio
device is reset then virtqueue elements are no longer valid.
This patch adds the discard_throttle_data() function to unmap the
scatter-gather list and decrement vq->inuse. This ensures that the
VirtQueueElement is freed properly.
Cc: amit.shah@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Add support for enabling the virtio 1.0 "emergency write"
(VIRTIO_CONSOLE_F_EMERG_WRITE) feature. The previous patch introduced
the plumbing required for this; now we expose the virtio feature to
the guest. The feature is disabled for compatibility machines to avoid
exposing a new feature to existing guests.
As required by the virtio 1.0 spec, the emergency write functionality
is available to the guest even if the guest doesn't negotatiate the
feature, as well as before feature negotation.
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Add the infrastructure required for the virtio 1.0 "emergency write"
(VIRTIO_CONSOLE_F_EMERG_WRITE) feature. Because we don't touch the
size of the configuration area, guests will not be able to actually
make use of this without further patches.
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The qemu_chr_fe_write method will return -1 on EAGAIN if the
chardev backend write would block. Almost no callers of the
qemu_chr_fe_write() method check the return value, instead
blindly assuming data was successfully sent. In most cases
this will lead to silent data loss on interactive consoles,
but in some cases (eg RNG EGD) it'll just cause corruption
of the protocol being spoken.
We unfortunately can't fix the virtio-console code, due to
a bug in the Linux guest drivers, which would cause the
entire Linux kernel to hang if we delay processing of the
incoming data in any way. Fixing this requires first fixing
the guest driver to not hold spinlocks while writing to the
hvc device backend.
Fixes bug: https://bugs.launchpad.net/qemu/+bug/1586756
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1473170165-540-4-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The write_console_data() method in sclpconsole-lm.c checks
whether the return value of qemu_chr_fe_write() has the
value of -EAGAIN and if so then increments the buffer offset
by the value of EAGAIN. Fortunately qemu_chr_fe_write() will
never return EAGAIN directly, rather it returns -1 with
errno set to EAGAIN, so this broken code path was not
reachable. The behaviour on EAGAIN was stil bad though,
causing the write_console_data() to busy_wait repeatedly
calling qemu_chr_fe_write() with no sleep between iters.
Just remove all this loop logic and replace with a call
to qemu_chr_fe_write_all().
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1473170165-540-3-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The isa_register_portio_list() function allocates ioports
data/state. Let's keep the reference to this data on some owner. This
isn't enough to fix leaks, but at least, ASAN stops complaining of
direct leaks. Further cleanup would require calling
portio_list_del/destroy().
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
The virtio-console.c file handles both serial consoles
and interactive consoles, since they're backed by the
same device model.
Since serial devices are expected to be reliable and
need to notify the guest when the backend is opened
or closed, the virtio-console.c file wires up support
for chardev events. This affects both serial consoles
and interactive consoles, using a network connection
based chardev backend such as 'socket', but not when
using a PTY based backend or plain 'file' backends.
When the host side is not connected the handle_output()
method in virtio-serial-bus.c will drop any data sent
by the guest, before it even reaches the virtio-console.c
code. This means that if the chardev has a logfile
configured, the data will never get logged.
Consider for example, configuring a x86_64 guest with a
plain UART serial port
-chardev socket,id=charserial1,host=127.0.0.1,port=9001,server,nowait,logfile=console1.log,logappend=on
-device isa-serial,chardev=charserial1,id=serial1
vs a s390 guest which has to use the virtio-console port
-chardev socket,id=charconsole1,host=127.0.0.1,port=9000,server,nowait,logfile=console2.log,logappend=on
-device virtconsole,chardev=charconsole1,id=console1
The isa-serial one gets data written to the log regardless
of whether a client is connected, while the virtioconsole
one only gets data written to the log when a client is
connected.
There is no need for virtio-serial-bus.c to aggressively
drop the data for console devices, as the chardev code is
prefectly capable of discarding the data itself.
So this patch changes virtconsole devices so that they
are always marked as having the host side open. This
ensures that the guest OS will always send any data it
has (Linux virtio-console hvc driver actually ignores
the host open state and sends data regardless, but we
should not rely on that), and also prevents the
virtio-serial-bus code prematurely discarding data.
The behaviour of virtserialport devices is *not* changed,
only virtconsole, because for the former, it is important
that the guest OSknow exactly when the host side is opened
/ closed so it can do any protocol re-negotiation that may
be required.
Fixes bug: https://bugs.launchpad.net/qemu/+bug/1599214
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1470241360-3574-2-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
