Re: [Qemu-devel] [PATCH] SH: Fix struct target_stat64 for 64bit host

[michael]

hi,

address@hidden wrote:
> Hi,
>
>   
> > I have some trouble using the qemu emulator on the x86_64 host system. 
> > The system emulate
> > an qemu-sh4 machine. I try to fix it without success:
> >     
>
> I found stat64 has damaged return address on stack because of bloated
>  struct stat64.
>
> On sh4 target, struct target_stat64 has "unsigned int" as its member.
> It may results unwanted struct layout on 64bit host. Switched to abi_ulong.
> We also have to use packed attribute for sh4, because the struct has
> unaligned 64bit member st_size.
>
>  Signed-off-by: Takashi YOSHII <address@hidden>
>
> ---
>  linux-user/syscall_defs.h |    6 +++---
>  1 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
> index 5a58010..01e48fd 100644
> --- a/linux-user/syscall_defs.h
> +++ b/linux-user/syscall_defs.h
> @@ -1475,15 +1475,15 @@ struct target_stat {
>  /* This matches struct stat64 in glibc2.1, hence the absolutely
>   * insane amounts of padding around dev_t's.
>   */
> -struct target_stat64 {
> +struct __attribute__((__packed__)) target_stat64 {
>         unsigned long long      st_dev;
>         unsigned char   __pad0[4];
>  
>  #define TARGET_STAT64_HAS_BROKEN_ST_INO	1
>         abi_ulong       __st_ino;
>  
> -	unsigned int	st_mode;
> -       unsigned int    st_nlink;
> +       abi_ulong       st_mode;
> +       abi_ulong       st_nlink;
>  
>  	abi_ulong	st_uid;
>         abi_ulong       st_gid;
>   
What would you think about this one?


Index: linux-user/syscall_defs.h
===================================================================
--- linux-user/syscall_defs.h   (revision 5499)
+++ linux-user/syscall_defs.h   (working copy)
@@ -1506,7 +1506,7 @@
        abi_ulong       target_st_ctime_nsec;
 
        unsigned long long      st_ino;
-};
+}  __attribute__((packed));
 
 #elif defined(TARGET_I386) && !defined(TARGET_ABI32)
 struct target_stat {