* Commit 3e76099aac ("loader: Allow a custom AddressSpace when loading
ROMs") introduced the "Rom.as" field:
(1) It modified the utility callers of rom_insert() to take "as" as a
new parameter from *their* callers, and set "rom->as" from that
parameter. The functions covered were rom_add_file() and
rom_add_elf_program().
(2) It also modified rom_insert() itself, to auto-assign
"&address_space_memory", in case the external caller passed -- and
the utility caller forwarded -- as=NULL.
Except, commit 3e76099aac forgot to update the third utility caller of
rom_insert(), under point (1), namely rom_add_blob().
* Later, commit 5e774eb3bd ("loader: Add AddressSpace loading support
to uImages") added the load_uimage_as() function, and the
rom_add_blob_fixed_as() function-like macro, with the necessary changes
elsewhere to propagate the new "as" parameter to rom_add_blob():
load_uimage_as()
load_uboot_image()
rom_add_blob_fixed_as()
rom_add_blob()
At this point, the signature (and workings) of rom_add_blob() had been
broken already, and the rom_add_blob_fixed_as() macro passed its "_as"
parameter to rom_add_blob() as "callback_opaque". Given that the
"fw_callback" parameter itself was set to NULL (correctly), this did no
additional damage (the opaque arg would never be used), but ultimately
it broke the new functionality of load_uimage_as().
* The load_uimage_as() function would be put to use in one of the later
patches, commit e481a1f63c ("generic-loader: Add a generic loader").
* We can fix this only in a unified patch now. Append "AddressSpace *as"
to the signature of rom_add_blob(), and handle the new parameter. Pass
NULL from all current callers, except from rom_add_blob_fixed_as(),
where "_as" has to be bumped to the proper position.
* Note that rom_add_file() rejects the case when both "mr" and "as" are
passed in as non-NULL. The action that this is apparently supposed to
prevent is the
rom->mr = mr;
assignment (that's the only place where the "mr" parameter is used in
rom_add_file()). In rom_add_blob() though, we have no "mr" parameter,
and the actions done on the fw_cfg branch:
if (fw_file_name && fw_cfg) {
if (mc->rom_file_has_mr) {
data = rom_set_mr(rom, OBJECT(fw_cfg), devpath);
mr = rom->mr;
} else {
data = rom->data;
}
reflect those that are performed by rom_add_file() too (with mr==NULL):
if (rom->fw_file && fw_cfg) {
if ((!option_rom || mc->option_rom_has_mr) &&
mc->rom_file_has_mr) {
data = rom_set_mr(rom, OBJECT(fw_cfg), devpath);
} else {
data = rom->data;
}
Hence we need no additional restrictions in rom_add_blob().
* Stable is not affected as both problematic commits appeared first in
v2.8.0-rc0.
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Alistair Francis <alistair.francis@xilinx.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Michael Walle <michael@walle.cc>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Shannon Zhao <zhaoshenglong@huawei.com>
Cc: qemu-arm@nongnu.org
Cc: qemu-devel@nongnu.org
Fixes: 3e76099aac
Fixes: 5e774eb3bd
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
QEMU README
===========
QEMU is a generic and open source machine & userspace emulator and
virtualizer.
QEMU is capable of emulating a complete machine in software without any
need for hardware virtualization support. By using dynamic translation,
it achieves very good performance. QEMU can also integrate with the Xen
and KVM hypervisors to provide emulated hardware while allowing the
hypervisor to manage the CPU. With hypervisor support, QEMU can achieve
near native performance for CPUs. When QEMU emulates CPUs directly it is
capable of running operating systems made for one machine (e.g. an ARMv7
board) on a different machine (e.g. an x86_64 PC board).
QEMU is also capable of providing userspace API virtualization for Linux
and BSD kernel interfaces. This allows binaries compiled against one
architecture ABI (e.g. the Linux PPC64 ABI) to be run on a host using a
different architecture ABI (e.g. the Linux x86_64 ABI). This does not
involve any hardware emulation, simply CPU and syscall emulation.
QEMU aims to fit into a variety of use cases. It can be invoked directly
by users wishing to have full control over its behaviour and settings.
It also aims to facilitate integration into higher level management
layers, by providing a stable command line interface and monitor API.
It is commonly invoked indirectly via the libvirt library when using
open source applications such as oVirt, OpenStack and virt-manager.
QEMU as a whole is released under the GNU General Public License,
version 2. For full licensing details, consult the LICENSE file.
Building
========
QEMU is multi-platform software intended to be buildable on all modern
Linux platforms, OS-X, Win32 (via the Mingw64 toolchain) and a variety
of other UNIX targets. The simple steps to build QEMU are:
mkdir build
cd build
../configure
make
Additional information can also be found online via the QEMU website:
http://qemu-project.org/Hosts/Linux
http://qemu-project.org/Hosts/W32
Submitting patches
==================
The QEMU source code is maintained under the GIT version control system.
git clone git://git.qemu-project.org/qemu.git
When submitting patches, the preferred approach is to use 'git
format-patch' and/or 'git send-email' to format & send the mail to the
qemu-devel@nongnu.org mailing list. All patches submitted must contain
a 'Signed-off-by' line from the author. Patches should follow the
guidelines set out in the HACKING and CODING_STYLE files.
Additional information on submitting patches can be found online via
the QEMU website
http://qemu-project.org/Contribute/SubmitAPatch
http://qemu-project.org/Contribute/TrivialPatches
Bug reporting
=============
The QEMU project uses Launchpad as its primary upstream bug tracker. Bugs
found when running code built from QEMU git or upstream released sources
should be reported via:
https://bugs.launchpad.net/qemu/
If using QEMU via an operating system vendor pre-built binary package, it
is preferable to report bugs to the vendor's own bug tracker first. If
the bug is also known to affect latest upstream code, it can also be
reported via launchpad.
For additional information on bug reporting consult:
http://qemu-project.org/Contribute/ReportABug
Contact
=======
The QEMU community can be contacted in a number of ways, with the two
main methods being email and IRC
- qemu-devel@nongnu.org
http://lists.nongnu.org/mailman/listinfo/qemu-devel
- #qemu on irc.oftc.net
Information on additional methods of contacting the community can be
found online via the QEMU website:
http://qemu-project.org/Contribute/StartHere
-- End
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