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![]() 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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.. | ||
aarch64 | ||
alpha | ||
arm | ||
cris | ||
generic | ||
host | ||
hppa | ||
i386 | ||
m68k | ||
microblaze | ||
mips | ||
mips64 | ||
nios2 | ||
openrisc | ||
ppc | ||
riscv | ||
s390x | ||
sh4 | ||
sparc | ||
sparc64 | ||
tilegx | ||
x86_64 | ||
xtensa | ||
cpu_loop-common.h | ||
elfload.c | ||
errno_defs.h | ||
exit.c | ||
flat.h | ||
flatload.c | ||
ioctls.h | ||
linux_loop.h | ||
linuxload.c | ||
m68k-sim.c | ||
main.c | ||
Makefile.objs | ||
mmap.c | ||
qemu.h | ||
safe-syscall.S | ||
signal-common.h | ||
signal.c | ||
socket.h | ||
strace.c | ||
strace.list | ||
syscall_defs.h | ||
syscall_types.h | ||
syscall.c | ||
target_flat.h | ||
trace-events | ||
uaccess.c | ||
uname.c | ||
uname.h | ||
vm86.c |