Devices may have component devices and buses.
Device realization may fail. Realization is recursive: a device's
realize() method realizes its components, and device_set_realized()
realizes its buses (which should in turn realize the devices on that
bus, except bus_set_realized() doesn't implement that, yet).
When realization of a component or bus fails, we need to roll back:
unrealize everything we realized so far. If any of these unrealizes
failed, the device would be left in an inconsistent state. Must not
happen.
device_set_realized() lets it happen: it ignores errors in the roll
back code starting at label child_realize_fail.
Since realization is recursive, unrealization must be recursive, too.
But how could a partly failed unrealize be rolled back? We'd have to
re-realize, which can fail. This design is fundamentally broken.
device_set_realized() does not roll back at all. Instead, it keeps
unrealizing, ignoring further errors.
It can screw up even for a device with no buses: if the lone
dc->unrealize() fails, it still unregisters vmstate, and calls
listeners' unrealize() callback.
bus_set_realized() does not roll back either. Instead, it stops
unrealizing.
Fortunately, no unrealize method can fail, as we'll see below.
To fix the design error, drop parameter @errp from all the unrealize
methods.
Any unrealize method that uses @errp now needs an update. This leads
us to unrealize() methods that can fail. Merely passing it to another
unrealize method cannot cause failure, though. Here are the ones that
do other things with @errp:
* virtio_serial_device_unrealize()
Fails when qbus_set_hotplug_handler() fails, but still does all the
other work. On failure, the device would stay realized with its
resources completely gone. Oops. Can't happen, because
qbus_set_hotplug_handler() can't actually fail here. Pass
&error_abort to qbus_set_hotplug_handler() instead.
* hw/ppc/spapr_drc.c's unrealize()
Fails when object_property_del() fails, but all the other work is
already done. On failure, the device would stay realized with its
vmstate registration gone. Oops. Can't happen, because
object_property_del() can't actually fail here. Pass &error_abort
to object_property_del() instead.
* spapr_phb_unrealize()
Fails and bails out when remove_drcs() fails, but other work is
already done. On failure, the device would stay realized with some
of its resources gone. Oops. remove_drcs() fails only when
chassis_from_bus()'s object_property_get_uint() fails, and it can't
here. Pass &error_abort to remove_drcs() instead.
Therefore, no unrealize method can fail before this patch.
device_set_realized()'s recursive unrealization via bus uses
object_property_set_bool(). Can't drop @errp there, so pass
&error_abort.
We similarly unrealize with object_property_set_bool() elsewhere,
always ignoring errors. Pass &error_abort instead.
Several unrealize methods no longer handle errors from other unrealize
methods: virtio_9p_device_unrealize(),
virtio_input_device_unrealize(), scsi_qdev_unrealize(), ...
Much of the deleted error handling looks wrong anyway.
One unrealize methods no longer ignore such errors:
usb_ehci_pci_exit().
Several realize methods no longer ignore errors when rolling back:
v9fs_device_realize_common(), pci_qdev_unrealize(),
spapr_phb_realize(), usb_qdev_realize(), vfio_ccw_realize(),
virtio_device_realize().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-17-armbru@redhat.com>
While loading the executable, some platforms (like AVR) need to
detect CPU type that executable is built for - and, with this patch,
this is enabled by reading the field 'e_flags' of the ELF header of
the executable in question. The change expands functionality of
the following functions:
- load_elf()
- load_elf_as()
- load_elf_ram()
- load_elf_ram_sym()
The argument added to these functions is called 'pflags' and is of
type 'uint32_t*' (that matches 'pointer to 'elf_word'', 'elf_word'
being the type of the field 'e_flags', in both 32-bit and 64-bit
variants of ELF header). Callers are allowed to pass NULL as that
argument, and in such case no lookup to the field 'e_flags' will
happen, and no information will be returned, of course.
CC: Richard Henderson <rth@twiddle.net>
CC: Peter Maydell <peter.maydell@linaro.org>
CC: Edgar E. Iglesias <edgar.iglesias@gmail.com>
CC: Michael Walle <michael@walle.cc>
CC: Thomas Huth <huth@tuxfamily.org>
CC: Laurent Vivier <laurent@vivier.eu>
CC: Philippe Mathieu-Daudé <f4bug@amsat.org>
CC: Aleksandar Rikalo <aleksandar.rikalo@rt-rk.com>
CC: Aurelien Jarno <aurelien@aurel32.net>
CC: Jia Liu <proljc@gmail.com>
CC: David Gibson <david@gibson.dropbear.id.au>
CC: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
CC: BALATON Zoltan <balaton@eik.bme.hu>
CC: Christian Borntraeger <borntraeger@de.ibm.com>
CC: Thomas Huth <thuth@redhat.com>
CC: Artyom Tarasenko <atar4qemu@gmail.com>
CC: Fabien Chouteau <chouteau@adacore.com>
CC: KONRAD Frederic <frederic.konrad@adacore.com>
CC: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Aleksandar Rikalo <aleksandar.rikalo@rt-rk.com>
Signed-off-by: Michael Rolnik <mrolnik@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Message-Id: <1580079311-20447-24-git-send-email-aleksandar.markovic@rt-rk.com>
Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190709152053.16670-2-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
[Rebased onto merge commit 95a9457fd44; missed instances of qom/cpu.h
in comments replaced]
In my "build everything" tree, changing hw/qdev-properties.h triggers
a recompile of some 2700 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).
Many places including hw/qdev-properties.h (directly or via hw/qdev.h)
actually need only hw/qdev-core.h. Include hw/qdev-core.h there
instead.
hw/qdev.h is actually pointless: all it does is include hw/qdev-core.h
and hw/qdev-properties.h, which in turn includes hw/qdev-core.h.
Replace the remaining uses of hw/qdev.h by hw/qdev-properties.h.
While there, delete a few superfluous inclusions of hw/qdev-core.h.
Touching hw/qdev-properties.h now recompiles some 1200 objects.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Daniel P. Berrangé" <berrange@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20190812052359.30071-22-armbru@redhat.com>
In my "build everything" tree, changing sysemu/reset.h triggers a
recompile of some 2600 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).
The main culprit is hw/hw.h, which supposedly includes it for
convenience.
Include sysemu/reset.h only where it's needed. Touching it now
recompiles less than 200 objects.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190812052359.30071-9-armbru@redhat.com>
This patch adds an optional function pointer, 'elf_note_fn', to
load_elf() which causes load_elf() to additionally parse any
ELF program headers of type PT_NOTE and check to see if the ELF
Note is of the type specified by the 'translate_opaque' arg.
If a matching ELF Note is found then the specfied function pointer
is called to process the ELF note.
Passing a NULL function pointer results in ELF Notes being skipped.
The first consumer of this functionality is the PVHboot support
which needs to read the XEN_ELFNOTE_PHYS32_ENTRY ELF Note while
loading the uncompressed kernel binary in order to discover the
boot entry address for the x86/HVM direct boot ABI.
Signed-off-by: Liam Merwick <liam.merwick@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The generic-loader is currently compiled target specific due to one
single "#ifdef TARGET_WORDS_BIGENDIAN" in the file. We have already a
function called target_words_bigendian() for this instead, so we can
put the generic-loader into common-obj to save some compilation time.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Each device that is instantiatable by the users should be marked with
a category. Since the generic-loader does not fit anywhere else, put
it into the MISC category.
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
This patch adds Intel Hexadecimal Object File format support to the
generic loader device. The file format specification is available here:
http://www.piclist.com/techref/fileext/hex/intel.htm
This file format is often used with microcontrollers such as the
micro:bit, Arduino, STM32, etc. Users expect to be able to run .hex
files directly with without first converting them to ELF. Most
micro:bit code is developed in web-based IDEs without direct user access
to binutils so it is important for QEMU to handle this file format
natively.
Signed-off-by: Su Hang <suhang16@mails.ucas.ac.cn>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20180814162739.11814-6-stefanha@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The documentation for the generic loader claims that you can
set the PC for a CPU with an option of the form
-device loader,cpu-num=0,addr=0x10000004
However if you try this QEMU complains:
cpu_num must be specified when setting a program counter
This is because we were testing against 0 rather than CPU_NONE.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180205150426.20542-1-peter.maydell@linaro.org
When running QEMU with "-M none -device loader,file=kernel.elf", it
currently crashes with a segmentation fault, because the "none"-machine
does not have any CPU by default and the generic loader code tries
to dereference s->cpu. Fix it by adding an appropriate check for a
NULL pointer.
Reported-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
This patch fixes the generic-loader file loading to only set the program
counter if a CPU is specified. This follows what is written in the
documentation and was always part of the original intention.
Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 537bf4d08be7acf7a89b590cff69e19db7f0a6cd.1478908712.git.alistair.francis@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Add a generic loader to QEMU which can be used to load images or set
memory values.
Internally inside QEMU this is a device. It is a strange device that
provides no hardware interface but allows QEMU to monkey patch memory
specified when it is created. To be able to do this it has a reset
callback that does the memory operations.
This device allows the user to monkey patch memory. To be able to do
this it needs a backend to manage the datas, the same as other
memory-related devices. In this case as the backend is so trivial we
have merged it with the frontend instead of creating and maintaining a
seperate backend.
Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 10f2a9dce5e5e11b6c6d959415b0ad6ee22bcba5.1475195078.git.alistair.francis@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
