mirror of https://github.com/xemu-project/xemu.git
![]() Qemu includes the glibc headers for the host defines and target headers are part of the qemu source themselves. The glibc has the F_GETLK64, F_SETLK64 and F_SETLKW64 defined to 12, 13 and 14 for all archs in sysdeps/unix/sysv/linux/bits/fcntl-linux.h. The linux kernel generic definition for F_*LK is 5, 6 & 7 and F_*LK64* is 12,13, and 14 as seen in include/uapi/asm-generic/fcntl.h. On 64bit machine, by default the kernel assumes all F_*LK to 64bit calls and doesnt support use of F_*LK64* as can be seen in include/linux/fcntl.h in linux source. On x86_64 host, the values for F_*LK64* are set to 5, 6 and 7 explicitly in /usr/include/x86_64-linux-gnu/bits/fcntl.h by the glibc. Whereas, a PPC64 host doesn't have such a definition in /usr/include/powerpc64le-linux-gnu/bits/fcntl.h by the glibc. So, the sources on PPC64 host sees the default value of F_*LK64* as 12, 13 & 14(fcntl-linux.h). Since the 64bit kernel doesnt support 12, 13 & 14; the glibc fcntl syscall implementation(__libc_fcntl*(), __fcntl64_nocancel) does the F_*LK64* value convertion back to F_*LK* values on PPC64 as seen in sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h with FCNTL_ADJUST_CMD() macro. Whereas on x86_64 host the values for F_*LK64* are set to 5, 6 and 7 and no adjustments are needed. Since qemu doesnt use the glibc fcntl, but makes the safe_syscall* on its own, the PPC64 qemu is calling the syscall with 12, 13, and 14(without adjustment) and they all fail. The fcntl calls to F_GETLK/F_SETLK|W all fail by all pplications run on PPC64 host user emulation. The fix here could be to see why on PPC64 the glibc is still keeping F_*LK64* different from F_*LK and why adjusting them to 5, 6 and 7 before the syscall for PPC only. See if we can make the /usr/include/powerpc64le-linux-gnu/bits/fcntl.h to have the values 5, 6 & 7 just like x86_64 and remove the adjustment code in glibc. That way, qemu sources see the kernel supported values in glibc headers. OR On PPC64 host, qemu sources see both F_*LK & F_*LK64* as same and set to 12, 13 and 14 because __USE_FILE_OFFSET64 is defined in qemu sources(also refer sysdeps/unix/sysv/linux/bits/fcntl-linux.h). Do the value adjustment just like it is done by glibc source by using F_GETLK value of 5. That way, we make the syscalls with the actual supported values in Qemu. The patch is taking this approach. Signed-off-by: Shivaprasad G Bhat <sbhat@linux.vnet.ibm.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Laurent Vivier <laurent@vivier.eu> Message-Id: <153148521235.87746.14142430397318741182.stgit@lep8c.aus.stglabs.ibm.com> Signed-off-by: Laurent Vivier <laurent@vivier.eu> |
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accel | ||
audio | ||
backends | ||
block | ||
bsd-user | ||
capstone@22ead3e0bf | ||
chardev | ||
contrib | ||
crypto | ||
default-configs | ||
disas | ||
docs | ||
dtc@e54388015a | ||
fpu | ||
fsdev | ||
gdb-xml | ||
hw | ||
include | ||
io | ||
libdecnumber | ||
linux-headers | ||
linux-user | ||
migration | ||
nbd | ||
net | ||
pc-bios | ||
po | ||
qapi | ||
qga | ||
qobject | ||
qom | ||
replay | ||
roms | ||
scripts | ||
scsi | ||
slirp | ||
stubs | ||
target | ||
tcg | ||
tests | ||
trace | ||
ui | ||
util | ||
.dir-locals.el | ||
.editorconfig | ||
.exrc | ||
.gdbinit | ||
.gitignore | ||
.gitmodules | ||
.gitpublish | ||
.mailmap | ||
.shippable.yml | ||
.travis.yml | ||
CODING_STYLE | ||
COPYING | ||
COPYING.LIB | ||
Changelog | ||
HACKING | ||
LICENSE | ||
MAINTAINERS | ||
Makefile | ||
Makefile.objs | ||
Makefile.target | ||
README | ||
VERSION | ||
arch_init.c | ||
balloon.c | ||
block.c | ||
blockdev-nbd.c | ||
blockdev.c | ||
blockjob.c | ||
bootdevice.c | ||
bt-host.c | ||
bt-vhci.c | ||
configure | ||
cpus-common.c | ||
cpus.c | ||
device-hotplug.c | ||
device_tree.c | ||
disas.c | ||
dma-helpers.c | ||
dump.c | ||
exec.c | ||
gdbstub.c | ||
hmp-commands-info.hx | ||
hmp-commands.hx | ||
hmp.c | ||
hmp.h | ||
ioport.c | ||
iothread.c | ||
job-qmp.c | ||
job.c | ||
memory.c | ||
memory_ldst.inc.c | ||
memory_mapping.c | ||
module-common.c | ||
monitor.c | ||
numa.c | ||
os-posix.c | ||
os-win32.c | ||
qdev-monitor.c | ||
qdict-test-data.txt | ||
qemu-bridge-helper.c | ||
qemu-doc.texi | ||
qemu-ga.texi | ||
qemu-img-cmds.hx | ||
qemu-img.c | ||
qemu-img.texi | ||
qemu-io-cmds.c | ||
qemu-io.c | ||
qemu-keymap.c | ||
qemu-nbd.c | ||
qemu-nbd.texi | ||
qemu-option-trace.texi | ||
qemu-options-wrapper.h | ||
qemu-options.h | ||
qemu-options.hx | ||
qemu-seccomp.c | ||
qemu-tech.texi | ||
qemu.nsi | ||
qemu.sasl | ||
qmp.c | ||
qtest.c | ||
replication.c | ||
replication.h | ||
rules.mak | ||
thunk.c | ||
tpm.c | ||
trace-events | ||
version.rc | ||
vl.c | ||
win_dump.c | ||
win_dump.h |
README
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: https://qemu.org/Hosts/Linux https://qemu.org/Hosts/Mac https://qemu.org/Hosts/W32 Submitting patches ================== The QEMU source code is maintained under the GIT version control system. git clone git://git.qemu.org/qemu.git When submitting patches, one common 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 https://qemu.org/Contribute/SubmitAPatch https://qemu.org/Contribute/TrivialPatches The QEMU website is also maintained under source control. git clone git://git.qemu.org/qemu-web.git https://www.qemu.org/2017/02/04/the-new-qemu-website-is-up/ A 'git-publish' utility was created to make above process less cumbersome, and is highly recommended for making regular contributions, or even just for sending consecutive patch series revisions. It also requires a working 'git send-email' setup, and by default doesn't automate everything, so you may want to go through the above steps manually for once. For installation instructions, please go to https://github.com/stefanha/git-publish The workflow with 'git-publish' is: $ git checkout master -b my-feature $ # work on new commits, add your 'Signed-off-by' lines to each $ git publish Your patch series will be sent and tagged as my-feature-v1 if you need to refer back to it in the future. Sending v2: $ git checkout my-feature # same topic branch $ # making changes to the commits (using 'git rebase', for example) $ git publish Your patch series will be sent with 'v2' tag in the subject and the git tip will be tagged as my-feature-v2. 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: https://qemu.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 https://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: https://qemu.org/Contribute/StartHere -- End