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.
Signed-off-by: Ilya Leoshkevich <[email protected]>
---
bsd-user/x86_64/target_arch_thread.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/bsd-user/x86_64/target_arch_thread.h
b/bsd-user/x86_64/target_arch_thread.h
index 52c28906d6d..25233443c14 100644
--- a/bsd-user/x86_64/target_arch_thread.h
+++ b/bsd-user/x86_64/target_arch_thread.h
@@ -31,7 +31,7 @@ static inline void target_thread_init(struct target_pt_regs
*regs,
struct image_info *infop)
{
regs->rax = 0;
- regs->rsp = infop->start_stack;
+ regs->rsp = (infop->start_stack & ~0xfUL) - 8;
regs->rip = infop->entry;
regs->rdi = infop->start_stack;
}
--
2.45.2
