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  1. 16 1月, 2018 1 次提交
    • E
      maint: Fix macros with broken 'do/while(0); ' usage · 2562755e
      由 Eric Blake 提交于 
      The point of writing a macro embedded in a 'do { ... } while (0)'
loop (particularly if the macro has multiple statements or would
otherwise end with an 'if' statement) is so that the macro can be
used as a drop-in statement with the caller supplying the
trailing ';'.  Although our coding style frowns on brace-less 'if':
  if (cond)
    statement;
  else
    something else;
that is the classic case where failure to use do/while(0) wrapping
would cause the 'else' to pair with any embedded 'if' in the macro
rather than the intended outer 'if'.  But conversely, if the macro
includes an embedded ';', then the same brace-less coding style
would now have two statements, making the 'else' a syntax error
rather than pairing with the outer 'if'.  Thus, even though our
coding style with required braces is not impacted, ending a macro
with ';' makes our code harder to port to projects that use
brace-less styles.

The change should have no semantic impact.  I was not able to
fully compile-test all of the changes (as some of them are
examples of the ugly bit-rotting debug print statements that are
completely elided by default, and I didn't want to recompile
with the necessary -D witnesses - cleaning those up is left as a
bite-sized task for another day); I did, however, audit that for
all files touched, all callers of the changed macros DID supply
a trailing ';' at the callsite, and did not appear to be used
as part of a brace-less conditional.

Found mechanically via: $ git grep -B1 'while (0);' | grep -A1 \\\\
Signed-off-by: NEric Blake <eblake@redhat.com>
Acked-by: NCornelia Huck <cohuck@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20171201232433.25193-7-eblake@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      2562755e
  3. 14 7月, 2017 1 次提交
  5. 24 10月, 2016 5 次提交
  7. 14 9月, 2016 1 次提交
    • D
      hw: replace most use of qemu_chr_fe_write with qemu_chr_fe_write_all · 6ab3fc32
      由 Daniel P. Berrange 提交于 
      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/1586756Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Message-Id: <1473170165-540-4-git-send-email-berrange@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      6ab3fc32
  9. 06 6月, 2016 1 次提交
  11. 19 5月, 2016 1 次提交
  13. 29 1月, 2016 1 次提交
  15. 02 4月, 2015 2 次提交
    • M
      sysbus: Make devices picking up backends unavailable with -device · 9f9bdf43
      由 Markus Armbruster 提交于 
      Device models aren't supposed to go on fishing expeditions for
backends.  They should expose suitable properties for the user to set.
For onboard devices, board code sets them.

A number of sysbus devices pick up block backends in their init() /
instance_init() methods with drive_get_next() instead: sl-nand,
milkymist-memcard, pl181, generic-sdhci.

Likewise, a number of sysbus devices pick up character backends in
their init() / realize() methods with qemu_char_get_next_serial():
cadence_uart, digic-uart, etraxfs,serial, lm32-juart, lm32-uart,
milkymist-uart, pl011, stm32f2xx-usart, xlnx.xps-uartlite.

All these mistakes are already marked FIXME.  See the commit that
added these FIXMEs for a more detailed explanation of what's wrong.

Fortunately, only machines ppce500 and pseries-* support -device with
sysbus devices, and none of the devices above is supported with these
machines.

Set cannot_instantiate_with_device_add_yet to preserve our luck.

Cc: Andrzej Zaborowski <balrogg@gmail.com>
Cc: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Cc: Antony Pavlov <antonynpavlov@gmail.com>
Cc: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>
Cc: Michael Walle <michael@walle.cc>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
      9f9bdf43
    • M
      hw: Mark devices picking up char backends actively FIXME · d71b22bb
      由 Markus Armbruster 提交于 
      Character devices defined with -serial and -parallel are for board
initialization to wire up.  Board code examines serial_hds[] and
parallel_hds[] to find them, and creates devices with their qdev
chardev properties set accordingly.

Except a few devices go on a fishing expedition for a suitable backend
instead of exposing a chardev property for board code to set: they use
serial_hds[] (often via qemu_char_get_next_serial()) or parallel_hds[]
in their realize() or init() method to connect to a backend.

Picking up backends that way works when the devices are created by
board code.  But it's inappropriate for -device or device_add.  Not
only is it inconsistent with how the other characrer device models
work (they connect to a backend explicitly identified by a "chardev"
property), it breaks when the backend has been picked up by the board
or a previous -device / device_add already.

Example:

    $ qemu-system-ppc64 -M bamboo -S -device i82378 -device pc87312 -device pc87312
    qemu-system-ppc64: -device pc87312: Property 'isa-parallel.chardev' can't take value 'parallel0', it's in use

Mark them with suitable FIXME comments.

Cc: Li Guang <lig.fnst@cn.fujitsu.com>
Cc: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Cc: Antony Pavlov <antonynpavlov@gmail.com>
Cc: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>
Cc: Michael Walle <michael@walle.cc>
Cc: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Cc: "Andreas Färber" <andreas.faerber@web.de>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
      d71b22bb
  17. 11 3月, 2015 1 次提交