Commit Graph

474 Commits

Author SHA1 Message Date
Paolo Bonzini fffbd9cf1b qemu-char: do not forward events through the mux until QEMU has started
Otherwise, the CHR_EVENT_OPENED event is sent twice: first when the
backend (for example "stdio") is opened, and second after processing
the command line.

The incorrect sending of the event prints the monitor banner when
QEMU is started with "-serial mon:stdio".  This includes the "(qemu)"
prompt; thus the monitor seems to be dead, whereas actually the
active front-end is the serial port.

Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Tested-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-11-02 09:28:56 +01:00
Peter Maydell 01b601f061 Merge qio 2016/10/27 v1
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Merge remote-tracking branch 'remotes/berrange/tags/pull-qio-2016-10-27-1' into staging

Merge qio 2016/10/27 v1

# gpg: Signature made Thu 27 Oct 2016 13:54:03 BST
# gpg:                using RSA key 0xBE86EBB415104FDF
# gpg: Good signature from "Daniel P. Berrange <dan@berrange.com>"
# gpg:                 aka "Daniel P. Berrange <berrange@redhat.com>"
# Primary key fingerprint: DAF3 A6FD B26B 6291 2D0E  8E3F BE86 EBB4 1510 4FDF

* remotes/berrange/tags/pull-qio-2016-10-27-1:
  main: set names for main loop sources created
  vnc: set name for all I/O channels created
  migration: set name for all I/O channels created
  char: set name for all I/O channels created
  nbd: set name for all I/O channels created
  io: add ability to set a name for IO channels
  io: Add a QIOChannelSocket cleanup test
  io: set LISTEN flag explicitly for listen sockets
  io: Introduce a qio_channel_set_feature() helper
  io: Use qio_channel_has_feature() where applicable
  io: Fix double shift usages on QIOChannel features

Conflicts:
	qemu-char.c

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-10-28 15:30:55 +01:00
Daniel P. Berrange e93a68e102 char: set name for all I/O channels created
Ensure that all I/O channels created for character devices
are given names to distinguish their respective roles.

Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-10-27 09:13:10 +02:00
Marc-André Lureau 82878dac6f char: remove explicit_be_open from CharDriverState
It's only used in qmp_chardev_add(), so use a create() argument instead.

Also switched to typedef functions for CharDriverParse/CharDriverCreate.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022100951.19562-7-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:46:11 +02:00
Marc-André Lureau ebf4c54d4b char: use common error path in qmp_chardev_add
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022100951.19562-6-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:46:10 +02:00
Marc-André Lureau 3aef23d7d8 char: replace avail_connections
No need to count the users of a CharDriverState, it can rely on the fact
of whether there is a CharBackend associated or if there is enough space
in the muxer.

Simplify and fold chr_mux_new_fe() in qemu_chr_fe_init() since there is
a single user now. Also switch from fprintf to raising error instead.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022100951.19562-5-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:46:10 +02:00
Marc-André Lureau 58fa54947e char: remove unused qemu_chr_fe_event
I introduced this function in d61b0c9a2f, but it isn't
used. Furthermore, it was incomplete, as it would need to translate QEMU
chr events to Spice port events.

(presumably it was used in the follow-up NBD-spice series that was not
completed: http://lists.gnu.org/archive/html/qemu-devel/2013-11/msg02024.html)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022100951.19562-4-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:46:10 +02:00
Marc-André Lureau 830896afe3 char: move fe_open in CharBackend
The fe_open state belongs to front end.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022100951.19562-1-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:46:10 +02:00
Marc-André Lureau 39ab61c6d0 char: remove explicit_fe_open, use a set_handlers argument
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>
2016-10-24 15:46:10 +02:00
Marc-André Lureau 72ac876248 char: rename chr_close/chr_free
The function is used to free the backend opaque pointer, let's name it
accordingly.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-23-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:46:10 +02:00
Marc-André Lureau a4afa548fc char: move front end handlers in CharBackend
Since the hanlders are associated with a CharBackend, rather than the
CharDriverState, it is more appropriate to store in CharBackend. This
avoids the handler copy dance in qemu_chr_fe_set_handlers() then
mux_chr_update_read_handler(), by storing the CharBackend pointer
directly.

Also a mux CharDriver should go through mux->backends[focused], since
chr->be will stay NULL. Before that, it was possible to call
chr->handler by mistake with surprising results, for ex through
qemu_chr_be_can_write(), which would result in calling the last set
handler front end, not the one with focus.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-22-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:46:10 +02:00
Marc-André Lureau fa394ed625 char: make some qemu_chr_fe skip if no driver
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>
2016-10-24 15:27:21 +02:00
Marc-André Lureau c39860e6dc char: replace qemu_chr_claim/release with qemu_chr_fe_init/deinit
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>
2016-10-24 15:27:21 +02:00
Marc-André Lureau 386f07d1fc char: fold qemu_chr_set_handlers in qemu_chr_fe_set_handlers
qemu_chr_add_handlers*() have been removed in previous change, so the
common qemu_chr_set_handlers() is no longer needed.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-17-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:27:21 +02:00
Marc-André Lureau 5345fdb446 char: use qemu_chr_fe* functions with CharBackend argument
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>
2016-10-24 15:27:21 +02:00
Marc-André Lureau 7fa47e2a80 char: rename some frontend functions
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>
2016-10-24 15:27:20 +02:00
Marc-André Lureau ecb672d14f char: start converting mux driver to use CharBackend
Start using qemu_chr_fe* CharBackend functions:
initialize a CharBackend and use qemu_chr_fe_set_handlers().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-11-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:27:20 +02:00
Marc-André Lureau 94a40fc560 char: introduce CharBackend
This new structure is meant to keep the details associated with a char
driver usage. On initialization, it gets a tag from the mux backend.
It can change its handlers thanks to qemu_chr_fe_set_handlers().

This structure is introduced so that all frontend will be moved to hold
and use a CharBackend. This will allow to better track char usage and
allocation, and help prevent some memory leaks or corruption.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-10-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:27:20 +02:00
Marc-André Lureau 6dfa8298fa mux: split mux_chr_update_read_handler()
Make qemu_chr_add_handlers_full() aware of mux handling. This allows
introduction of a tag associated with the fe handlers and a
qemu_chr_set_handlers() function to set the handler for a particular
tag. That will allow to get rid of qemu_chr_add_handlers*() in later
changes, in favor of qemu_chr_fe_set_handler().

To this end, chr_update_read_handler callback is enhanced with a tag
argument, and mux_chr_update_read_handler() is splitted in new
functions: mux_chr_new_handler_tag(), mux_chr_set_handlers(),
mux_set_focus().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-9-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:27:20 +02:00
Marc-André Lureau b4948be93e char: remove init callback
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>
2016-10-24 15:27:20 +02:00
Marc-André Lureau 5c936a83c3 ringbuf: fix chr_write return value
It should return the number of written bytes.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-4-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:27:20 +02:00
Marc-André Lureau ba60e727b0 char: remove use-after-free on win-stdio
Found by reviewing the code, win_stdio_close() is called by
qemu_chr_free() which then call qemu_chr_free_common() taking care of
freeing CharDriverState*.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-3-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:27:19 +02:00
Marc-André Lureau 692d88b408 Revert "char: use a fixed idx for child muxed chr"
That commit mis-used mux char: the frontend are multiplexed, not the
backend. Fix the regression preventing "c-a c" to switch the focus. The
following patches will fix the crash (when leaving or removing frontend)
by tracking frontends with handler tags.

This reverts commit 949055a254.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-10-13 13:56:31 +01:00
Peter Maydell 627eae7d72 virtio, pc: fixes and features
more guest error handling for virtio devices
 virtio migration rework
 pc fixes
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio, pc: fixes and features

more guest error handling for virtio devices
virtio migration rework
pc fixes

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Mon 10 Oct 2016 00:39:11 BST
# gpg:                using RSA key 0x281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>"
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream: (33 commits)
  intel-iommu: Check IOAPIC's Trigger Mode against the one in IRTE
  virtio: cleanup VMSTATE_VIRTIO_DEVICE
  vhost-vsock: convert VMSTATE_VIRTIO_DEVICE
  virtio-rng: convert VMSTATE_VIRTIO_DEVICE
  virtio-balloon: convert VMSTATE_VIRTIO_DEVICE
  virtio-scsi: convert VMSTATE_VIRTIO_DEVICE
  virtio-input: convert VMSTATE_VIRTIO_DEVICE
  virtio-gpu: convert VMSTATE_VIRTIO_DEVICE
  virtio-serial: convert VMSTATE_VIRTIO_DEVICE
  virtio-9p: convert VMSTATE_VIRTIO_DEVICE
  virtio-net: convert VMSTATE_VIRTIO_DEVICE
  virtio-blk: convert VMSTATE_VIRTIO_DEVICE
  virtio: prepare change VMSTATE_VIRTIO_DEVICE macro
  net: don't poke at chardev internal QemuOpts
  virtio-scsi: handle virtio_scsi_set_config() error
  virtio-scsi: convert virtio_scsi_bad_req() to use virtio_error()
  virtio-net: handle virtio_net_flush_tx() errors
  virtio-net: handle virtio_net_receive() errors
  virtio-net: handle virtio_net_handle_ctrl() error
  virtio-blk: handle virtio_blk_handle_request() errors
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-10-10 16:23:40 +01:00
Peter Maydell a20fd901af trivial patches for 2016-10-08
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Merge remote-tracking branch 'remotes/mjt/tags/trivial-patches-fetch' into staging

trivial patches for 2016-10-08

# gpg: Signature made Sat 08 Oct 2016 09:56:38 BST
# gpg:                using RSA key 0x701B4F6B1A693E59
# gpg: Good signature from "Michael Tokarev <mjt@tls.msk.ru>"
# gpg:                 aka "Michael Tokarev <mjt@corpit.ru>"
# gpg:                 aka "Michael Tokarev <mjt@debian.org>"
# Primary key fingerprint: 6EE1 95D1 886E 8FFB 810D  4324 457C E0A0 8044 65C5
#      Subkey fingerprint: 7B73 BAD6 8BE7 A2C2 8931  4B22 701B 4F6B 1A69 3E59

* remotes/mjt/tags/trivial-patches-fetch: (26 commits)
  net/filter-mirror: Fix mirror initial check typo
  virtio: rename the bar index field name in VirtIOPCIProxy
  linux-user: include <poll.h> instead of <sys/poll.h>
  char: fix missing return in error path for chardev TLS init
  CODING_STYLE: Fix a typo ("have" vs. "has")
  bitmap: refine and move BITMAP_{FIRST/LAST}_WORD_MASK
  build-sys: fix find-in-path
  m68k: change default system clock for m5208evb
  exec: remove unused compacted argument
  usb: ehci: fix memory leak in ehci_process_itd
  qapi: make the json schema files more regular.
  maint: Add module_block.h to .gitignore
  MAINTAINERS: Some updates related to the SH4 machines
  MAINTAINERS: Add some more MIPS related files
  MAINTAINERS: Add usermode related config files
  MAINTAINERS: Add some more pattern to recognize all win32 related files
  MAINTAINERS: Add some more rocker related files
  MAINTAINERS: Add header files to CRIS section
  MAINTAINERS: Add some more files to the virtio section
  MAINTAINERS: Add some SPARC machine related files
  ...

# Conflicts:
#	MAINTAINERS
2016-10-10 13:01:43 +01:00
Daniel P. Berrange 0a73336d96 net: don't poke at chardev internal QemuOpts
The vhost-user & colo code is poking at the QemuOpts instance
in the CharDriverState struct, not realizing that it is valid
for this to be NULL. e.g. the following crash shows a codepath
where it will be NULL:

 Program terminated with signal SIGSEGV, Segmentation fault.
 #0  0x000055baf6ab4adc in qemu_opt_foreach (opts=0x0, func=0x55baf696b650 <net_vhost_chardev_opts>, opaque=0x7ffc51368c00, errp=0x7ffc51368e48) at util/qemu-option.c:617
 617         QTAILQ_FOREACH(opt, &opts->head, next) {
 [Current thread is 1 (Thread 0x7f1d4970bb40 (LWP 6603))]
 (gdb) bt
 #0  0x000055baf6ab4adc in qemu_opt_foreach (opts=0x0, func=0x55baf696b650 <net_vhost_chardev_opts>, opaque=0x7ffc51368c00, errp=0x7ffc51368e48) at util/qemu-option.c:617
 #1  0x000055baf696b7da in net_vhost_parse_chardev (opts=0x55baf8ff9260, errp=0x7ffc51368e48) at net/vhost-user.c:314
 #2  0x000055baf696b985 in net_init_vhost_user (netdev=0x55baf8ff9250, name=0x55baf879d270 "hostnet2", peer=0x0, errp=0x7ffc51368e48) at net/vhost-user.c:360
 #3  0x000055baf6960216 in net_client_init1 (object=0x55baf8ff9250, is_netdev=true, errp=0x7ffc51368e48) at net/net.c:1051
 #4  0x000055baf6960518 in net_client_init (opts=0x55baf776e7e0, is_netdev=true, errp=0x7ffc51368f00) at net/net.c:1108
 #5  0x000055baf696083f in netdev_add (opts=0x55baf776e7e0, errp=0x7ffc51368f00) at net/net.c:1186
 #6  0x000055baf69608c7 in qmp_netdev_add (qdict=0x55baf7afaf60, ret=0x7ffc51368f50, errp=0x7ffc51368f48) at net/net.c:1205
 #7  0x000055baf6622135 in handle_qmp_command (parser=0x55baf77fb590, tokens=0x7f1d24011960) at /path/to/qemu.git/monitor.c:3978
 #8  0x000055baf6a9d099 in json_message_process_token (lexer=0x55baf77fb598, input=0x55baf75acd20, type=JSON_RCURLY, x=113, y=19) at qobject/json-streamer.c:105
 #9  0x000055baf6abf7aa in json_lexer_feed_char (lexer=0x55baf77fb598, ch=125 '}', flush=false) at qobject/json-lexer.c:319
 #10 0x000055baf6abf8f2 in json_lexer_feed (lexer=0x55baf77fb598, buffer=0x7ffc51369170 "}R\204\367\272U", size=1) at qobject/json-lexer.c:369
 #11 0x000055baf6a9d13c in json_message_parser_feed (parser=0x55baf77fb590, buffer=0x7ffc51369170 "}R\204\367\272U", size=1) at qobject/json-streamer.c:124
 #12 0x000055baf66221f7 in monitor_qmp_read (opaque=0x55baf77fb530, buf=0x7ffc51369170 "}R\204\367\272U", size=1) at /path/to/qemu.git/monitor.c:3994
 #13 0x000055baf6757014 in qemu_chr_be_write_impl (s=0x55baf7610a40, buf=0x7ffc51369170 "}R\204\367\272U", len=1) at qemu-char.c:387
 #14 0x000055baf6757076 in qemu_chr_be_write (s=0x55baf7610a40, buf=0x7ffc51369170 "}R\204\367\272U", len=1) at qemu-char.c:399
 #15 0x000055baf675b3b0 in tcp_chr_read (chan=0x55baf90244b0, cond=G_IO_IN, opaque=0x55baf7610a40) at qemu-char.c:2927
 #16 0x000055baf6a5d655 in qio_channel_fd_source_dispatch (source=0x55baf7610df0, callback=0x55baf675b25a <tcp_chr_read>, user_data=0x55baf7610a40) at io/channel-watch.c:84
 #17 0x00007f1d3e80cbbd in g_main_context_dispatch () from /usr/lib64/libglib-2.0.so.0
 #18 0x000055baf69d3720 in glib_pollfds_poll () at main-loop.c:213
 #19 0x000055baf69d37fd in os_host_main_loop_wait (timeout=126000000) at main-loop.c:258
 #20 0x000055baf69d38ad in main_loop_wait (nonblocking=0) at main-loop.c:506
 #21 0x000055baf676587b in main_loop () at vl.c:1908
 #22 0x000055baf676d3bf in main (argc=101, argv=0x7ffc5136a6c8, envp=0x7ffc5136a9f8) at vl.c:4604
 (gdb) p opts
 $1 = (QemuOpts *) 0x0

The crash occurred when attaching vhost-user net via QMP:

{
    "execute": "chardev-add",
    "arguments": {
        "id": "charnet2",
        "backend": {
            "type": "socket",
            "data": {
                "addr": {
                    "type": "unix",
                    "data": {
                        "path": "/var/run/openvswitch/vhost-user1"
                    }
                },
                "wait": false,
                "server": false
            }
        }
    },
    "id": "libvirt-19"
}
{
    "return": {

    },
    "id": "libvirt-19"
}
{
    "execute": "netdev_add",
    "arguments": {
        "type": "vhost-user",
        "chardev": "charnet2",
        "id": "hostnet2"
    },
    "id": "libvirt-20"
}

Code using chardevs should not be poking at the internals of the
CharDriverState struct. What vhost-user wants is a chardev that is
operating as reconnectable network service, along with the ability
to do FD passing over the connection. The colo code simply wants
a network service. Add a feature concept to the char drivers so
that chardev users can query the actual features they wish to have
supported. The QemuOpts member is removed to prevent future mistakes
in this area.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10 01:46:29 +03:00
Daniel P. Berrange 660a2d83e0 char: fix missing return in error path for chardev TLS init
If the qio_channel_tls_new_(server|client) methods fail,
we disconnect the client. Unfortunately a missing return
means we then go on to try and run the TLS handshake on
a NULL I/O channel. This gives predictably segfaulty
results.

The main way to trigger this is to request a bogus TLS
priority string for the TLS credentials. e.g.

  -object tls-creds-x509,id=tls0,priority=wibble,...

Most other ways appear impossible to trigger except
perhaps if OOM conditions cause gnutls initialization
to fail.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-10-08 11:25:29 +03:00
Marc-André Lureau 6a7b2b2100 char: update read handler in all cases
In commit ac1b84dd1 (rhbz#1027181), a check was added to only update the
"read handler" when the front-end is opened, because the read callbacks
were not restored when a device is plugged. However, this seems not
correct, the handler is correctly set back on hotplug (in
virtconsole_realize) and the bug can no longer be reproduced.

Calling chr_update_read_handler() allows to fix the mux driver to stop
calling the child handlers (which may be going to be destroyed).

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161003094704.18087-2-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-04 10:00:26 +02:00
Marc-André Lureau 949055a254 char: use a fixed idx for child muxed chr
mux_chr_update_read_handler() is adding a new mux_cnt each time
mux_chr_update_read_handler() is called, it's not possible to actually
update the "child" chr callbacks that were set previously. This may lead
to crashes if the "child" chr is destroyed:

valgrind x86_64-softmmu/qemu-system-x86_64 -chardev
stdio,mux=on,id=char0 -mon chardev=char0,mode=control,default

when quitting:

==4306== Invalid read of size 8
==4306==    at 0x8061D3: json_lexer_destroy (json-lexer.c:385)
==4306==    by 0x7E39F8: json_message_parser_destroy (json-streamer.c:134)
==4306==    by 0x3447F6: monitor_qmp_event (monitor.c:3908)
==4306==    by 0x480153: mux_chr_send_event (qemu-char.c:630)
==4306==    by 0x480694: mux_chr_event (qemu-char.c:734)
==4306==    by 0x47F1E9: qemu_chr_be_event (qemu-char.c:205)
==4306==    by 0x481207: fd_chr_close (qemu-char.c:1114)
==4306==    by 0x481659: qemu_chr_close_stdio (qemu-char.c:1221)
==4306==    by 0x486F07: qemu_chr_free (qemu-char.c:4146)
==4306==    by 0x486F97: qemu_chr_delete (qemu-char.c:4154)
==4306==    by 0x487E66: qemu_chr_cleanup (qemu-char.c:4678)
==4306==    by 0x495A98: main (vl.c:4675)
==4306==  Address 0x28439e90 is 112 bytes inside a block of size 240 free'd
==4306==    at 0x4C2CD5A: free (vg_replace_malloc.c:530)
==4306==    by 0x1E4CBF2D: g_free (in /usr/lib64/libglib-2.0.so.0.4800.2)
==4306==    by 0x344DE9: monitor_cleanup (monitor.c:4058)
==4306==    by 0x495A93: main (vl.c:4674)
==4306==  Block was alloc'd at
==4306==    at 0x4C2BBAD: malloc (vg_replace_malloc.c:299)
==4306==    by 0x1E4CBE18: g_malloc (in /usr/lib64/libglib-2.0.so.0.4800.2)
==4306==    by 0x344BF8: monitor_init (monitor.c:4021)
==4306==    by 0x49063C: mon_init_func (vl.c:2417)
==4306==    by 0x7FC6DE: qemu_opts_foreach (qemu-option.c:1116)
==4306==    by 0x4954E0: main (vl.c:4473)

Instead, keep the "child" chr associated with a particular idx so its
handlers can be updated and removed to avoid the crash.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161003094704.18087-3-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-04 10:00:26 +02:00
Zhang Chen e92aa36ac8 qemu-char: Add qemu_chr_add_handlers_full() for GMaincontext
Add qemu_chr_add_handlers_full() API, we can use
this API pass in a GMainContext,make handler run
in the context rather than main_loop.
This comments from Daniel P . Berrange.

Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-09-27 17:54:21 +08:00
Lin Ma 71200fb966 qemu-char: avoid segfault if user lacks of permisson of a given logfile
Function qemu_chr_alloc returns NULL if it failed to open logfile by any reason,
says no write permission. For backends tty, stdio and msmouse, They need to
check this return value to avoid segfault in this case.

Signed-off-by: Lin Ma <lma@suse.com>
Cc: qemu-stable <qemu-stable@nongnu.org>
Message-Id: <20160914062250.22226-1-lma@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-14 22:52:43 +02:00
Daniel P. Berrange 90f998f5f4 char: convert qemu_chr_fe_write to qemu_chr_fe_write_all
The mux chardev was not checking the return value of any
qemu_chr_fe_write() call so would silently loose data
on EAGAIN.

Similarly the qemu_chr_fe_printf method would not check
errors and was not in a position to retry even if it
could check.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1473170165-540-5-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13 19:09:43 +02:00
Lin Ma 517b3d4016 chardev: Add 'help' option to print all available chardev backend types
Signed-off-by: Lin Ma <lma@suse.com>
Message-Id: <20160816171352.17021-1-lma@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13 19:08:47 +02:00
Marc-André Lureau 1dc8a6695c char: fix waiting for TLS and telnet connection
Since commit d7a04fd7d5, tcp_chr_wait_connected() was introduced,
so vhost-user could wait until a backend started successfully. In
vhost-user case, the chr socket must be plain unix, and the chr+vhost
setup happens synchronously during qemu startup.

However, with TLS and telnet socket, initial socket setup happens
asynchronously, and s->connected is not set after the socket is
accepted. In order for tcp_chr_wait_connected() to not keep accepting
new connections and proceed with the last accepted socket, it can
check for s->ioc instead.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20160816083332.15088-1-marcandre.lureau@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-08-16 11:50:55 +01:00
Marc-André Lureau 1371a36936 char: free MuxDriver when closing
Similarly to other chr_close callbacks, free char type specific data.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-08-08 00:00:15 +04:00
Marc-André Lureau 5b498459b4 char: free the tcp connection data when closing
Make sure the connection data got freed when closing the chardev, to
avoid leaks. Introduce tcp_chr_free_connection() to clean all connection
related data, and move some tcp_chr_close() clean-ups there.

(while at it, set write_msgfds_num to 0 when clearing array in
tcp_set_msgfds())

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2016-08-08 00:00:11 +04:00
Stefan Weil c025f689a1 wxx: Fix handling of files used for character devices
On Windows, such files were not truncated like on all other hosts.
Now we also test whether truncation is needed when running on Windows.

The append case was also incorrect because it needs a different value
for the desired access mode.

Reported-by: Benjamin David Lunt <fys@fysnet.net>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1470114877-1466-1-git-send-email-sw@weilnetz.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-08-05 14:15:14 +01:00
Marc-André Lureau d7a04fd7d5 char: add and use tcp_chr_wait_connected
Add a chr_wait_connected for the tcp backend, and use it in the
open_socket() function.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-29 00:33:48 +03:00
Marc-André Lureau 6b6723c3b5 char: add chr_wait_connected callback
A function to wait on the backend to be connected, to be used in the
following patches.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-29 00:33:48 +03:00
Marc-André Lureau 5c7eaabf65 qemu-char: fix qemu_chr_fe_set_msgfds() crash when disconnected
Calling qemu_chr_fe_set_msgfds() on unconnected socket leads to crash
since s->ioc is NULL in this case. Return an error earlier instead.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-29 00:33:47 +03:00
Marc-André Lureau aa5cb7f5e8 char: do not use atexit cleanup handler
It turns out qemu is calling exit() in various places from various
threads without taking much care of resources state. The atexit()
cleanup handlers cannot easily destroy resources that are in use (by
the same thread or other).

Since c1111a24a3, TCG arm guests run into the following abort() when
running tests, the chardev mutex is locked during the write, so
qemu_mutex_destroy() returns an error:

 #0  0x00007fffdbb806f5 in raise () at /lib64/libc.so.6
 #1  0x00007fffdbb822fa in abort () at /lib64/libc.so.6
 #2  0x00005555557616fe in error_exit (err=<optimized out>, msg=msg@entry=0x555555c38c30 <__func__.14622> "qemu_mutex_destroy")
     at /home/drjones/code/qemu/util/qemu-thread-posix.c:39
 #3  0x0000555555b0be20 in qemu_mutex_destroy (mutex=mutex@entry=0x5555566aa0e0) at /home/drjones/code/qemu/util/qemu-thread-posix.c:57
 #4  0x00005555558aab00 in qemu_chr_free_common (chr=0x5555566aa0e0) at /home/drjones/code/qemu/qemu-char.c:4029
 #5  0x00005555558b05f9 in qemu_chr_delete (chr=<optimized out>) at /home/drjones/code/qemu/qemu-char.c:4038
 #6  0x00005555558b05f9 in qemu_chr_delete (chr=<optimized out>) at /home/drjones/code/qemu/qemu-char.c:4044
 #7  0x00005555558b062c in qemu_chr_cleanup () at /home/drjones/code/qemu/qemu-char.c:4557
 #8  0x00007fffdbb851e8 in __run_exit_handlers () at /lib64/libc.so.6
 #9  0x00007fffdbb85235 in  () at /lib64/libc.so.6
 #10 0x00005555558d1b39 in testdev_write (testdev=0x5555566aa0a0) at /home/drjones/code/qemu/backends/testdev.c:71
 #11 0x00005555558d1b39 in testdev_write (chr=<optimized out>, buf=0x7fffc343fd9a "", len=0) at /home/drjones/code/qemu/backends/testdev.c:95
 #12 0x00005555558adced in qemu_chr_fe_write (s=0x5555566aa0e0, buf=buf@entry=0x7fffc343fd98 "0q", len=len@entry=2) at /home/drjones/code/qemu/qemu-char.c:282

Instead of using a atexit() handler, only run the chardev cleanup as
initially proposed at the end of main(), where there are less chances
(hic) of conflicts or other races.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reported-by: Andrew Jones <drjones@redhat.com>
Message-Id: <20160704153823.16879-1-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-13 13:30:00 +02:00
Eric Blake 37f9e0a2b6 sockets: Use new QAPI cloning
Rather than rolling our own clone via an expensive conversion
in and back out of QObject, use the new clone visitor.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1465490926-28625-15-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-07-06 10:52:04 +02:00
Marc-André Lureau c1111a24a3 char: clean up remaining chardevs when leaving
This helps to remove various chardev resources leaks when leaving qemu.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1466105332-10285-2-git-send-email-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-29 16:49:41 +02:00
Paolo Bonzini 6f1de6b70d char: change qemu_chr_fe_add_watch to return unsigned
g_source_attach can return any value between 1 and UINT_MAX if you let
QEMU run long enough.  However, qemu_chr_fe_add_watch can also return
a negative errno value when the device is disconnected or does not
support chr_add_watch.  Change it to return zero to avoid overloading
these values.

Fix the cadence_uart which asserts in this case (easily obtained with
"-serial pty").

Tested-by: Bret Ketchum <bcketchum@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-29 14:03:47 +02:00
Peter Maydell 7263a903c3 pc, pci, virtio: new features, cleanups, fixes
Beginning of reconnect support for vhost-user.
 Misc cleanups and fixes.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

pc, pci, virtio: new features, cleanups, fixes

Beginning of reconnect support for vhost-user.
Misc cleanups and fixes.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Fri 17 Jun 2016 01:28:39 BST
# gpg:                using RSA key 0x281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>"
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream:
  MAINTAINERS: add Marcel to PCI
  msi_init: change return value to 0 on success
  fix some coding style problems
  pci core: assert ENOSPC when add capability
  test: start vhost-user reconnect test
  tests: append i386 tests
  vhost-net: save & restore vring enable state
  vhost-net: save & restore vhost-user acked features
  vhost-net: do not crash if backend is not present
  vhost-user: disconnect on start failure
  qemu-char: add qemu_chr_disconnect to close a fd accepted by listen fd
  tests/vhost-user-bridge: workaround stale vring base
  tests/vhost-user-bridge: add client mode
  vhost-user: add ability to know vhost-user backend disconnection
  pci: fix pci_requester_id()

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Conflicts:
	tests/Makefile.include
2016-06-17 11:25:46 +01:00
Tetsuya Mukawa 7d9d17f71e qemu-char: add qemu_chr_disconnect to close a fd accepted by listen fd
The patch introduces qemu_chr_disconnect(). The function is used for
closing a fd accepted by listen fd. Though we already have qemu_chr_delete(),
but it closes not only accepted fd but also listen fd. This new function
is used when we still want to keep listen fd.

Signed-off-by: Tetsuya Mukawa <mukawa@igel.co.jp>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Victor Kaplansky <victork@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-06-17 03:28:02 +03:00
Paolo Bonzini 02d0e09503 os-posix: include sys/mman.h
qemu/osdep.h checks whether MAP_ANONYMOUS is defined, but this check
is bogus without a previous inclusion of sys/mman.h.  Include it in
sysemu/os-posix.h and remove it from everywhere else.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16 18:39:03 +02:00
xiaoqiang zhao e5fabad7cc char: get rid of qemu_char_get_next_serial
since there is no user of qemu_char_get_next_serial any more,
it's time to let it go away.

Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: xiaoqiang zhao <zxq_yx_007@163.com>
Message-id: 1465028065-5855-7-git-send-email-zxq_yx_007@163.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-06-06 16:59:32 +01:00
Daniel P. Berrange 64c800f808 char: ensure all clients are in non-blocking mode
Only some callers of tcp_chr_new_client are putting the
socket client into non-blocking mode. Move the call to
qio_channel_set_blocking() into the tcp_chr_new_client
method to guarantee that all code paths set non-blocking
mode

Reported-by: Andrew Baumann <Andrew.Baumann@microsoft.com>
Reported-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1458324041-22709-1-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-04-05 11:46:52 +02:00
Daniel P. Berrange 53628efbc8 char: fix broken EAGAIN retry on OS-X due to errno clobbering
Some of the chardev I/O paths really want to write the
complete data buffer even though the channel is in
non-blocking mode. To achieve this they look for EAGAIN
and g_usleep() for 100ms. Unfortunately the code is set
to check errno == EAGAIN a second time, after the g_usleep()
call has completed. On OS-X at least, g_usleep clobbers
errno to ETIMEDOUT, causing the retry to be skipped.

This failure to retry means the full data isn't written
to the chardev backend, which causes various failures
including making the tests/ahci-test qtest hang.

Rather than playing games trying to reset errno just
simplify the code to use a goto to retry instead of a
a loop.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1459438168-8146-2-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-04-05 11:46:52 +02:00