diff options
| author | Ilya Leoshkevich <iii@linux.ibm.com> | 2024-07-31 16:44:12 +0200 |
|---|---|---|
| committer | Warner Losh <imp@bsdimp.com> | 2024-11-04 20:26:40 -0700 |
| commit | 1f31243a8c80fac27e52cc362cb1e2c922cf0e1b (patch) | |
| tree | 290b827b2b75619b423f2f00fc0145598bffdf45 /bsd-user | |
| parent | daaf51001a13da007d7dde72e1ed3b06bc490791 (diff) | |
bsd-user/x86_64/target_arch_thread.h: Align stack
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>
Diffstat (limited to 'bsd-user')
| -rw-r--r-- | bsd-user/x86_64/target_arch_thread.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/bsd-user/x86_64/target_arch_thread.h b/bsd-user/x86_64/target_arch_thread.h index 52c28906d6..7739bb2154 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 - 8) & ~0xfUL) + 8; regs->rip = infop->entry; regs->rdi = infop->start_stack; } |