bsd-user qemu-x86_64 almost immediately dies with:
qemu: 0x4002201a68: unhandled CPU exception 0xd - aborting
on FreeBSD 14.1-RELEASE. This is an instruction that requires
alignment:
(gdb) x/i 0x4002201a68
0x4002201a68: movaps %xmm0,-0x40(%rbp)
and the argument is not aligned:
(gdb) p/x env->regs[5]
$1 = 0x822443b58
A quick experiment shows that the userspace entry point expects
misaligned rsp:
(gdb) starti
(gdb) p/x $rsp
$1 = 0x7fffffffeaa8
Emulate this behavior in bsd-user.
[[ applied Richard's suggestion ]]
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Signed-off-by: Warner Losh <imp@bsdimp.com>
1f31243a8c