Alex Bligh [Wed, 21 Aug 2013 15:02:53 +0000 (16:02 +0100)]
aio / timers: Convert aio_poll to use AioContext timers' deadline
Convert aio_poll to use deadline based on AioContext's timers.
aio_poll has been changed to return accurately whether progress
has occurred. Prior to this commit, aio_poll always returned
true if g_poll was entered, whether or not any progress was
made. This required a change to tests/test-aio.c where an
assert was backwards.
Alex Bligh [Wed, 21 Aug 2013 15:02:48 +0000 (16:02 +0100)]
aio / timers: Add QEMUTimerListGroup and helper functions
Add QEMUTimerListGroup and helper functions, to represent
a QEMUTimerList associated with each clock. Add a default
QEMUTimerListGroup representing the default timer lists
which are not associated with any other object (e.g.
an AioContext as added by future patches).
Alex Bligh [Wed, 21 Aug 2013 15:02:47 +0000 (16:02 +0100)]
aio / timers: Untangle include files
include/qemu/timer.h has no need to include main-loop.h and
doing so causes an issue for the next patch. Unfortunately
various files assume including timers.h will pull in main-loop.h.
Untangle this mess.
Alex Bligh [Wed, 21 Aug 2013 15:02:46 +0000 (16:02 +0100)]
aio / timers: Split QEMUClock into QEMUClock and QEMUTimerList
Split QEMUClock into QEMUClock and QEMUTimerList so that we can
have more than one QEMUTimerList associated with the same clock.
Introduce a main_loop_timerlist concept and make existing
qemu_clock_* calls that actually should operate on a QEMUTimerList
call the relevant QEMUTimerList implementations, using the clock's
default timerlist. This vastly reduces the invasiveness of this
change and means the API stays constant for existing users.
Introduce a list of QEMUTimerLists associated with each clock
so that reenabling the clock can cause all the notifiers
to be called. Note the code to do the notifications is added
in a later patch.
Switch QEMUClockType to an enum. Remove global variables vm_clock,
host_clock and rt_clock and add compatibility defines. Do not
fix qemu_next_alarm_deadline as it's going to be deleted.
Add qemu_clock_use_for_deadline to indicate whether a particular
clock should be used for deadline calculations. When use_icount
is true, vm_clock should not be used for deadline calculations
as it does not contain a nanosecond count. Instead, icount
timeouts come from the execution thread doing aio_notify or
qemu_notify as appropriate. This function is used in the next
patch.
Alex Bligh [Wed, 21 Aug 2013 15:02:39 +0000 (16:02 +0100)]
aio / timers: Rename qemu_timer_* functions
Rename four functions in preparation for new API.
Rename qemu_timer_expired to timer_expired
Rename qemu_timer_expire_time_ns to timer_expire_time_ns
Rename qemu_timer_pending to timer_pending
Rename qemu_timer_expired_ns to timer_expired_ns
Paolo Bonzini [Mon, 19 Aug 2013 10:54:28 +0000 (18:54 +0800)]
vmdk: support vmfs files
VMware ESX hosts also use different create and extent types for flat
files, respectively "vmfs" and "VMFS". This is not documented, but it
can be found at http://kb.vmware.com/kb/10002511 (Recreating a missing
virtual machine disk (VMDK) descriptor file).
Fam Zheng [Mon, 19 Aug 2013 10:54:27 +0000 (18:54 +0800)]
vmdk: support vmfsSparse files
VMware ESX hosts use a variant of the VMDK3 format, identified by the
vmfsSparse create type ad the VMFSSPARSE extent type.
It has 16 KB grain tables (L2) and a variable-size grain directory (L1).
In addition, the grain size is always 512, but that is not a problem
because it is included in the header.
The format of the extents is documented in the VMDK spec. The format
of the descriptor file is not documented precisely, but it can be
found at http://kb.vmware.com/kb/10026353 (Recreating a missing virtual
machine disk (VMDK) descriptor file for delta disks).
With these patches, vmfsSparse files only work if opened through the
descriptor file. Data files without descriptor files, as far as I
could understand, are not supported by ESX.
Signed-off-by: Paolo Bonzini <[email protected]> Signed-off-by: Fam Zheng <[email protected]>
--
v2: Rebase to patch 01.
Change le64_to_cpu to le32_to_cpu.
Rename vmdk_open_vmdk3 to vmdk_open_vmfs_sparse, which represents the
current usage of this format.
Fam Zheng [Thu, 22 Aug 2013 07:36:59 +0000 (15:36 +0800)]
block: better error message for read only format name
When user tries to use read-only whitelist format in the command line
option, failure message was "'foo' invalid format". It might be invalid
only for writable, but valid for read-only, so it is confusing. Give the
user easier to understand information.
Notice the open -g option to set bs->growable. This means you can
read/write beyond end of file. Reading beyond end of file is supposed
to produce zeroes.
We rely on this behavior in qcow2_create2() during qcow2 image
creation. We create a new file and then write the qcow2 header
structure using bdrv_pwrite(). Since QCowHeader is not a multiple of
sector size, block.c first uses bdrv_read() on the empty file to fetch
the first sector (should be all zeroes).
Here is the output from the qemu-io NBD example above:
$ qemu-io -c 'open -g nbd+unix:///?socket=/tmp/nbd.sock' -c 'read -v 0 512' 00000000: ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab ................ 00000010: ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab ................ 00000020: ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab ................
...
We are not zeroing the buffer! As a result qcow2 image creation on top
of protocols is not guaranteed to work even when file creation is
supported by the protocol.
[Adapted this patch to use bs->zero_beyond_eof.
-- Stefan]
Asias He [Thu, 22 Aug 2013 07:24:14 +0000 (15:24 +0800)]
block: Introduce bs->zero_beyond_eof
In 4146b46c42e0989cb5842e04d88ab6ccb1713a48 (block: Produce zeros when
protocols reading beyond end of file), we break qemu-iotests ./check
-qcow2 022. This happens because qcow2 temporarily sets ->growable = 1
for vmstate accesses (which are stored beyond the end of regular image
data).
We introduce the bs->zero_beyond_eof to allow qcow2_load_vmstate() to
disable ->zero_beyond_eof temporarily in addition to enable ->growable.
[Since the broken patch "block: Produce zeros when protocols reading
beyond end of file" has not been merged yet, I have applied this fix
*first* and will then apply the next patch to keep the tree bisectable.
-- Stefan]
Kevin Wolf [Mon, 19 Aug 2013 08:38:01 +0000 (10:38 +0200)]
qcow2: Change default for new images to compat=1.1
By the time that qemu 1.7 will be released, enough time will have passed
since qemu 1.1, which is the first version to understand version 3
images, that changing the default shouldn't hurt many people any more
and the benefits of using the new format outweigh the pain.
qemu-iotests already runs with compat=1.1 by default.
Anthony Liguori [Tue, 20 Aug 2013 16:23:52 +0000 (11:23 -0500)]
Merge remote-tracking branch 'pmaydell/tags/pull-target-arm-20130820' into staging
target-arm queue
# gpg: Signature made Tue 20 Aug 2013 08:56:28 AM CDT using RSA key ID 14360CDE
# gpg: Can't check signature: public key not found
# By Peter Maydell (20) and Peter Chubb (1)
# Via Peter Maydell
* pmaydell/tags/pull-target-arm-20130820: (21 commits)
hw/timer/imx_epit: Simplify and fix imx_epit implementation
default-configs: Fix A9MP and A15MP config names
hw/cpu/a15mpcore: Wire generic timer outputs to GIC inputs
target-arm: Implement the generic timer
target-arm: Support coprocessor registers which do I/O
target-arm: Allow raw_read() and raw_write() to handle 64 bit regs
hw/arm/pic_cpu: Remove the now-unneeded arm_pic_init_cpu()
hw/arm/xilinx_zynq: Don't use arm_pic_init_cpu()
hw/arm/vexpress: Don't use arm_pic_init_cpu()
hw/arm/versatilepb: Don't use arm_pic_init_cpu()
hw/arm/strongarm: Don't use arm_pic_init_cpu()
hw/arm/realview: Don't use arm_pic_init_cpu()
hw/arm/omap*: Don't use arm_pic_init_cpu()
hw/arm/musicpal: Don't use arm_pic_init_cpu()
hw/arm/kzm: Don't use arm_pic_init_cpu()
hw/arm/integratorcp: Don't use arm_pic_init_cpu()
hw/arm/highbank: Don't use arm_pic_init_cpu()
hw/arm/exynos4210: Don't use arm_pic_init_cpu()
hw/arm/armv7m: Don't use arm_pic_init_cpu()
target-arm: Make IRQ and FIQ gpio lines on the CPU object
...
Anthony Liguori [Tue, 20 Aug 2013 14:52:18 +0000 (09:52 -0500)]
Merge remote-tracking branch 'stefanha/block-next' into staging
# By Stefan Hajnoczi
# Via Stefan Hajnoczi
* stefanha/block-next:
aio: drop io_flush argument
tests: drop event_active_cb()
thread-pool: drop thread_pool_active()
dataplane/virtio-blk: drop flush_true() and flush_io()
block/ssh: drop return_true()
block/sheepdog: drop have_co_req() and aio_flush_request()
block/rbd: drop qemu_rbd_aio_flush_cb()
block/nbd: drop nbd_have_request()
block/linux-aio: drop qemu_laio_completion_cb()
block/iscsi: drop iscsi_process_flush()
block/gluster: drop qemu_gluster_aio_flush_cb()
block/curl: drop curl_aio_flush()
aio: stop using .io_flush()
tests: adjust test-thread-pool to new aio_poll() semantics
tests: adjust test-aio to new aio_poll() semantics
dataplane/virtio-blk: check exit conditions before aio_poll()
block: stop relying on io_flush() in bdrv_drain_all()
block: ensure bdrv_drain_all() works during bdrv_delete()
Anthony Liguori [Tue, 20 Aug 2013 14:52:07 +0000 (09:52 -0500)]
Merge remote-tracking branch 'rth/axp-next' into staging
# By Richard Henderson
# Via Richard Henderson
* rth/axp-next:
target-alpha: Implement the typhoon iommu
target-alpha: Consider the superpage when threading and ending TBs
target-alpha: Use goto_tb in call_pal
target-alpha: Implement call_pal without an exception
Anthony Liguori [Tue, 20 Aug 2013 14:51:53 +0000 (09:51 -0500)]
Merge remote-tracking branch 'afaerber/tags/qom-cpu-for-anthony' into staging
QOM CPUState refactorings / X86CPU
* gdbstub coprocessor register count bugfix
* QOM instance_post_init infrastructure to override dynamic properties
* X86CPU HyperV preparations for CPU subclasses
# gpg: Signature made Fri 16 Aug 2013 11:49:02 AM CDT using RSA key ID 3E7E013F
# gpg: Can't check signature: public key not found
# By Eduardo Habkost (3) and others
# Via Andreas Färber
* afaerber/tags/qom-cpu-for-anthony:
cpus: Use cpu_is_stopped() efficiently
target-i386: Move hyperv_* static globals to X86CPU
qdev: Set globals in instance_post_init function
qom: Introduce instance_post_init hook
tests: Unit tests for qdev global properties handling
gdbstub: Fix gdb_register_coprocessor() register counting
Peter Chubb [Tue, 20 Aug 2013 13:54:32 +0000 (14:54 +0100)]
hw/timer/imx_epit: Simplify and fix imx_epit implementation
When imx_epit.c was last refactored, a common usecase (comparison
register zero) broke. This patch fixes that, and simplifies the code
yet more. It also fixes a major thinko in the reset path --- the
wrong bits in the control register were being cleared.
Peter Maydell [Tue, 20 Aug 2013 13:54:32 +0000 (14:54 +0100)]
default-configs: Fix A9MP and A15MP config names
When individual CONFIG_ switches for the A9MPcore and A15MPcore
devices were created, they were inadvertently given incorrect names
(CONFIG_ARM9MPCORE and CONFIG_ARM15MPCORE). These CPUs are
"Cortex-A9MP" and "Cortex-A15MP", and in particular the ARM9 is
a different (rather older) CPU than the Cortex-A9. Rename the
CONFIG_ switches to bring them into line with the source file
names and CPU names.
Peter Maydell [Tue, 20 Aug 2013 13:54:31 +0000 (14:54 +0100)]
target-arm: Implement the generic timer
The ARMv7 architecture specifies a 'generic timer' which is implemented
via cp15 registers. Newer kernels will prefer to use this rather than
a devboard-level timer. Implement the generic timer for TCG; for KVM
we will already use the hardware's virtualized timer for this.
Peter Maydell [Tue, 20 Aug 2013 13:54:31 +0000 (14:54 +0100)]
target-arm: Support coprocessor registers which do I/O
Add an ARM_CP_IO flag which an ARMCPRegInfo definition can use to
indicate that the register's implementation does I/O and thus
its accesses need to be surrounded by gen_io_start()/gen_io_end()
in order for icount to work. Most notably, cp registers which
implement clocks or timers need this.
Peter Maydell [Tue, 20 Aug 2013 13:54:28 +0000 (14:54 +0100)]
target-arm: Make IRQ and FIQ gpio lines on the CPU object
Now that ARMCPU is a subclass of DeviceState, we can make the
CPU's inbound IRQ and FIQ lines be simply gpio lines, which
means we can remove the odd arm_pic shim.
We retain the arm_pic_init_cpu() function as a backwards
compatibility shim layer so we can convert the board models
to get the IRQ and FIQ lines directly from the ARMCPU
object one at a time.
Peter Maydell [Tue, 20 Aug 2013 13:54:28 +0000 (14:54 +0100)]
target-arm: Implement 'int' loglevel
The 'int' loglevel for recording interrupts and exceptions
requires support in the target-specific code. Implement
it for ARM. This improves debug logging in some situations
that were otherwise pretty opaque, such as when we fault
trying to execute at an exception vector address, which
would otherwise cause an infinite loop of taking exceptions
without any indication in the debug log of what was going on.
Stefan Hajnoczi [Thu, 11 Apr 2013 15:22:08 +0000 (17:22 +0200)]
thread-pool: drop thread_pool_active()
.io_flush() is no longer called so drop thread_pool_active(). The block
layer is the only thread-pool.c user and it already tracks in-flight
requests, therefore we do not need thread_pool_active().
Stefan Hajnoczi [Thu, 11 Apr 2013 15:07:43 +0000 (17:07 +0200)]
block/gluster: drop qemu_gluster_aio_flush_cb()
Since .io_flush() is no longer called we do not need
qemu_gluster_aio_flush_cb() anymore. It turns out that qemu_aio_count
is unused now and can be dropped.
Thanks to Bharata B Rao <[email protected]> for catching a
build failure with CONFIG_GLUSTERFS_DISCARD, which has been fixed.
Stefan Hajnoczi [Thu, 11 Apr 2013 15:04:23 +0000 (17:04 +0200)]
block/curl: drop curl_aio_flush()
.io_flush() is no longer called so drop curl_aio_flush(). The acb[]
array that the function checks is still used in other parts of
block/curl.c. Therefore we cannot remove acb[], it is needed.
Stefan Hajnoczi [Thu, 11 Apr 2013 14:56:50 +0000 (16:56 +0200)]
aio: stop using .io_flush()
Now that aio_poll() users check their termination condition themselves,
it is no longer necessary to call .io_flush() handlers.
The behavior of aio_poll() changes as follows:
1. .io_flush() is no longer invoked and file descriptors are *always*
monitored. Previously returning 0 from .io_flush() would skip this file
descriptor.
Due to this change it is essential to check that requests are pending
before calling qemu_aio_wait(). Failure to do so means we block, for
example, waiting for an idle iSCSI socket to become readable when there
are no requests. Currently all qemu_aio_wait()/aio_poll() callers check
before calling.
2. aio_poll() now returns true if progress was made (BH or fd handlers
executed) and false otherwise. Previously it would return true whenever
'busy', which means that .io_flush() returned true. The 'busy' concept
no longer exists so just progress is returned.
Due to this change we need to update tests/test-aio.c which asserts
aio_poll() return values. Note that QEMU doesn't actually rely on these
return values so only tests/test-aio.c cares.
Note that ctx->notifier, the EventNotifier fd used for aio_notify(), is
now handled as a special case. This is a little ugly but maintains
aio_poll() semantics, i.e. aio_notify() does not count as 'progress' and
aio_poll() avoids blocking when the user has not set any fd handlers yet.
Patches after this remove .io_flush() handler code until we can finally
drop the io_flush arguments to aio_set_fd_handler() and friends.
Stefan Hajnoczi [Tue, 16 Apr 2013 15:49:42 +0000 (17:49 +0200)]
tests: adjust test-thread-pool to new aio_poll() semantics
aio_poll(ctx, true) will soon block when fd handlers have been set.
Previously aio_poll() would return early if all .io_flush() returned
false. This means we need to check the equivalent of the .io_flush()
condition *before* calling aio_poll(ctx, true) to avoid deadlock.
Stefan Hajnoczi [Thu, 11 Apr 2013 15:24:08 +0000 (17:24 +0200)]
dataplane/virtio-blk: check exit conditions before aio_poll()
Check exit conditions before entering blocking aio_poll(). This is
mainly for consistency since it's unlikely that we are stopping in the
first event loop iteration.
Stefan Hajnoczi [Thu, 11 Apr 2013 13:41:13 +0000 (15:41 +0200)]
block: stop relying on io_flush() in bdrv_drain_all()
If a block driver has no file descriptors to monitor but there are still
active requests, it can return 1 from .io_flush(). This is used to spin
during synchronous I/O.
Stop relying on .io_flush() and instead check
QLIST_EMPTY(&bs->tracked_requests) to decide whether there are active
requests.
This is the first step in removing .io_flush() so that event loops no
longer need to have the concept of synchronous I/O. Eventually we may
be able to kill synchronous I/O completely by running everything in a
coroutine, but that is future work.
Note this patch moves bs->throttled_reqs initialization to bdrv_new() so
that bdrv_requests_pending(bs) can safely access it. In practice bs is
g_malloc0() so the memory is already zeroed but it's safer to initialize
the queue properly.
We also need to fix up block/stream.c:close_unused_images() to prevent
traversing a dangling pointer while it rearranges the backing file
chain. This is necessary since the new bdrv_drain_all() traverses the
backing file chain.
Stefan Hajnoczi [Thu, 27 Jun 2013 13:32:26 +0000 (15:32 +0200)]
block: ensure bdrv_drain_all() works during bdrv_delete()
In bdrv_delete() make sure to call bdrv_make_anon() *after* bdrv_close()
so that the device is still seen by bdrv_drain_all() when iterating
bdrv_states.
Commit a0e372f0c49ac01faeaeb73a6e8f50e8ac615f34 reorganized the register
counting for GDB. While it seems correct not to let the total number of
registers skyrocket in an SMP scenario through a static variable, the
distinction between total register count and 'g' packet register count
(last_reg vs. num_g_regs) got lost among the way.
Fix this by introducing CPUState::gdb_num_g_regs and using that in
gdb_handle_packet().
Aurelien Jarno [Mon, 12 Aug 2013 19:34:53 +0000 (21:34 +0200)]
mips_malta: do not raise exceptions when accessing invalid memory
Since commit c658b94f6e8c206c59d02aa6fbac285b86b53d2c, MIPS raises
exceptions when accessing invalid memory. This is not the correct
behaviour for MIPS Malta Core LV, as the GT-64120A system controller
just ignore undecoded access. This feature is used by the Linux kernel
to probe for some devices.
Emulate the correct behaviour in QEMU by adding an empty slot covering
the entire memory space decoded by the GT-64120A.
James Hogan [Thu, 8 Aug 2013 11:09:38 +0000 (12:09 +0100)]
qemu-char: fix infinite recursion connecting to monitor pty
Since commit bd5c51e (qemu-char: don't issue CHR_EVENT_OPEN in a BH), an
infinite recursion occurs when putting the monitor on a pty (-monitor
pty) and connecting a terminal to the slave port.
This is because of the qemu_chr_be_event(s, CHR_EVENT_OPENED) added to
qemu_chr_be_generic_open(). This event is captured by monitor_event()
which prints a welcome message to the character device. The flush of
that welcome message retriggers another open event in pty_chr_state()
because it checks s->connected, but only sets it to 1 after calling
qemu_chr_be_generic_open().
I've fixed this by setting s->connected = 1 before the call to
qemu_chr_be_generic_open() instead of after, so that the recursive
pty_chr_state() doesn't call it again.
An example snippet of repeating backtrace:
...
#107486 0x007aec58 in monitor_flush (mon=0xf418b0) at qemu/monitor.c:288
#107487 0x007aee7c in monitor_puts (mon=0xf418b0, str=0x1176d07 "") at qemu/monitor.c:322
#107488 0x007aef20 in monitor_vprintf (mon=0xf418b0, fmt=0x8d4820 "QEMU %s monitor - type 'help' for more information\n",
ap=0x7f432be0) at qemu/monitor.c:339
#107489 0x007aefac in monitor_printf (mon=0xf418b0, fmt=0x8d4820 "QEMU %s monitor - type 'help' for more information\n")
at qemu/monitor.c:347
#107490 0x007ba4bc in monitor_event (opaque=0xf418b0, event=2) at qemu/monitor.c:4699
#107491 0x00684c28 in qemu_chr_be_event (s=0xf37788, event=2) at qemu/qemu-char.c:108
#107492 0x00684c70 in qemu_chr_be_generic_open (s=0xf37788) at qemu/qemu-char.c:113
#107493 0x006880a4 in pty_chr_state (chr=0xf37788, connected=1) at qemu/qemu-char.c:1145
#107494 0x00687fa4 in pty_chr_update_read_handler (chr=0xf37788) at qemu/qemu-char.c:1121
#107495 0x00687c9c in pty_chr_write (chr=0xf37788, buf=0x70b3c008 <Address 0x70b3c008 out of bounds>, len=538720)
at qemu/qemu-char.c:1063
#107496 0x00684cc4 in qemu_chr_fe_write (s=0xf37788, buf=0x70b3c008 <Address 0x70b3c008 out of bounds>, len=538720)
at qemu/qemu-char.c:118
...
Marcel Apfelbaum [Sun, 11 Aug 2013 15:10:42 +0000 (18:10 +0300)]
hw/misc: don't create pvpanic device by default
This patch is based on Hu Tao's:
http://lists.nongnu.org/archive/html/qemu-devel/2013-08/msg00124.html
No need to hard-code pvpanic as part of the machine.
It can be added with "-device pvpanic" from command line (The next patch).
Anyway, for backport compatibility it is still part of 1.5
machine.
Eduardo Habkost [Fri, 9 Aug 2013 14:11:36 +0000 (11:11 -0300)]
pc: Remove PCLMULQDQ from Westmere on pc-*-1.4 and older
Commit 41cb383f42d0cb51d8e3e25e3ecebc954dd4196f made a guest-visible
change by adding the PCLMULQDQ bit to Westmere without adding
compatibility code to keep the ABI for older machine-types.
Fix it by adding the missing compat code.
If the user is listening on '[::]', then we will not have a opened a device
yet and have no way of verifying if the device is RoCE or not.
In this case, the source VM will throw an error for ALL types of
connections (both IPv4 and IPv6) if the destination machine does not have
a regular infiniband network available for use.
The only way to gaurantee that an error is thrown for broken kernels is
for the management software to choose a *specific* interface at bind time
and validate what time of hardware it is.
Unfortunately, this puts the user in a fix:
If the source VM connects with an IPv4 address without knowing that the
destination has bound to '[::]' the migration will unconditionally fail
unless the management software is not explicitly listening on the the IPv4
address while using a RoCE-based device.
If the source VM connects with an IPv6 address, then we're OK because we can
throw an error on the source (and similarly on the destination).
But in mixed environments, this will be broken for a while until it is fixed
inside linux.
We do provide a *tiny* bit of help in mixed environments, though in this patch:
We can list all of the devices in the system and check to see if all the
devices are RoCE or Infiniband.
If we detect that we have a *pure* RoCE environment, then we can safely
thrown an error even if the management sofware has specified '[::]' as the
bind address.
However, if there is are multiple hetergeneous devices, then we cannot make
this assumption and the user just has to be sure they know what they are doing.
Paolo Bonzini [Fri, 9 Aug 2013 17:35:01 +0000 (12:35 -0500)]
pc_sysfw: remove the rom_only property
With the new semantics of pc_sysfw (no -pflash implies "old-style" ROM setup,
-pflash implies "new-style" ROM setup), there is no need anymore for a compat
property. Old machines simply will never use -pflash, and thus will always
use old-style setup.
This cleans up after 9e1c2ec (which accidentally left variable
pc_sysfw_flash_vs_rom_bug_compatible behind, value always zero), and
buries dead code from commit dafb82e (which resurrected the pc_sysfw
code for pc_sysfw_flash_vs_rom_bug_compatible by mistake).
qemu-option: Guard against qemu_opts_set_defaults() misuse
Commit 6d4cd40 fixed qemu_opts_set_defaults() for an existing corner
case, but broke it for another one that can't be reached in current
code.
Quote from its commit message:
I believe [opts_parse()] attempts to do the following:
If options don't yet exist, create new options
Else, if defaults, modify the existing options
Else, if list->merge_lists, modify the existing options
Else, fail
The only caller that passes true for defaults is
qemu_opts_set_defaults().
The commit message then claims:
A straightforward call of qemu_opts_create() does exactly that.
Wrong. When !list->merge_lists, and the option string doesn't contain
id=, and options without ID exist, then we don't actually modify the
existing options, we create new ones.
Not reachable, because we never pass lists with !list->merge_lists to
qemu_opts_set_defaults().
Guard against possible (if unlikely) future misuse with assert().
projects / qemu.git / log