Commit Graph

6 Commits

Author SHA1 Message Date
Michael Roth
bd5c51ee6c qemu-char: don't issue CHR_EVENT_OPEN in a BH
When CHR_EVENT_OPENED was initially added, it was CHR_EVENT_RESET,
and it was issued as a bottom-half:

86e94dea5b

Which we basically used to print out a greeting/prompt for the
monitor.

AFAICT the only reason this was ever done in a BH was because in
some cases we'd modify the chr_write handler for a new chardev
backend *after* the site where we issued the reset (see:
86e94d:qemu_chr_open_stdio())

At some point this event was renamed to CHR_EVENT_OPENED, and we've
maintained the use of this BH ever since.

However, due to 9f939df955, we schedule
the BH via g_idle_add(), which is causing events to sometimes be
delivered after we've already begun processing data from backends,
leading to:

 known bugs:

  QMP:
    session negotation resets with OPENED event, in some cases this
    is causing new sessions to get sporadically reset

 potential bugs:

  hw/usb/redirect.c:
    can_read handler checks for dev->parser != NULL, which may be
    true if CLOSED BH has not been executed yet. In the past, OPENED
    quiesced outstanding CLOSED events prior to us reading client
    data. If it's delayed, our check may allow reads to occur even
    though we haven't processed the OPENED event yet, and when we
    do finally get the OPENED event, our state may get reset.

  qtest.c:
    can begin session before OPENED event is processed, leading to
    a spurious reset of the system and irq_levels

  gdbstub.c:
    may start a gdb session prior to the machine being paused

To fix these, let's just drop the BH.

Since the initial reasoning for using it still applies to an extent,
work around that by deferring the delivery of CHR_EVENT_OPENED until
after the chardevs have been fully initialized, toward the end of
qmp_chardev_add() (or some cases, qemu_chr_new_from_opts()). This
defers delivery long enough that we can be assured a CharDriverState
is fully initialized before CHR_EVENT_OPENED is sent.

Also, rather than requiring each chardev to do an explicit open, do it
automatically, and allow the small few who don't desire such behavior to
suppress the OPENED-on-init behavior by setting a 'explicit_be_open'
flag.

We additionally add missing OPENED events for stdio backends on w32,
which were previously not being issued, causing us to not recieve the
banner and initial prompts for qmp/hmp.

Reported-by: Stefan Priebe <s.priebe@profihost.ag>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Message-id: 1370636393-21044-1-git-send-email-mdroth@linux.vnet.ibm.com
Cc: qemu-stable@nongnu.org
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-06-10 11:38:37 -05:00
Paolo Bonzini
dccfcd0e5f sysemu: avoid proliferation of include/ subdirectories
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-04-15 18:19:25 +02:00
Hans de Goede
fee204fd46 qemu-char: Rename qemu_chr_generic_open to qemu_chr_be_generic_open
To better reflect that it is for handling a backend being opened.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Message-id: 1364292483-16564-3-git-send-email-hdegoede@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-27 10:26:49 -05:00
Gerd Hoffmann
2d57286da6 chardev: add braille support to qapi
This patch adds 'braille' support to qapi and also switches over
the braille chardev initialization to the new qapi code path.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2013-03-13 10:27:46 +01:00
Anthony Liguori
6e72a00f90 Merge remote-tracking branch 'bonzini/hw-dirs' into staging
* bonzini/hw-dirs:
  sh: move files referencing CPU to hw/sh4/
  ppc: move more files to hw/ppc
  ppc: move files referencing CPU to hw/ppc/
  m68k: move files referencing CPU to hw/m68k/
  i386: move files referencing CPU to hw/i386/
  arm: move files referencing CPU to hw/arm/
  hw: move boards and other isolated files to hw/ARCH
  ppc: express FDT dependency of pSeries and e500 boards via default-configs/
  build: always link device_tree.o into emulators if libfdt available
  hw: include hw header files with full paths
  ppc: do not use ../ in include files
  vt82c686: vt82c686 is not a PCI host bridge
  virtio-9p: remove PCI dependencies from hw/9pfs/
  virtio-9p: use CONFIG_VIRTFS, not CONFIG_LINUX
  hw: move device-hotplug.o to toplevel, compile it once
  hw: move qdev-monitor.o to toplevel directory
  hw: move fifo.[ch] to libqemuutil
  hw: move char backends to backends/

Conflicts:
	backends/baum.c
	backends/msmouse.c
	hw/a15mpcore.c
	hw/arm/Makefile.objs
	hw/arm/pic_cpu.c
	hw/dataplane/event-poll.c
	hw/dataplane/virtio-blk.c
	include/char/baum.h
	include/char/msmouse.h
	qemu-char.c
	vl.c

Resolve conflicts caused by header movements.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-10 19:56:35 -05:00
Paolo Bonzini
159b6e9f14 hw: move char backends to backends/
Braille and msmouse support is in hw/, but it is not hardware.
Move it to the backends/ directory.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-03-01 13:18:23 +01:00