diff mbox

[v2] linux-user: make binfmt flag O require P

Message ID 1405363942-6865-1-git-send-email-Joakim.Tjernlund@transmode.se
State New
Headers show

Commit Message

Joakim Tjernlund July 14, 2014, 6:52 p.m. UTC 
Qemu can autodetect if it is started from Linux binfmt loader
when binfmt flag O is on.
Use that and require binfmt flag P as well which will enable QEMU
to pass in correct argv0 to the application.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
---
 linux-user/main.c           | 13 ++++++++++++-
 scripts/qemu-binfmt-conf.sh | 36 ++++++++++++++++++------------------
 2 files changed, 30 insertions(+), 19 deletions(-)

Comments

Andreas Färber July 14, 2014, 8:14 p.m. UTC | #1 
Am 14.07.2014 20:52, schrieb Joakim Tjernlund:
> Qemu can autodetect if it is started from Linux binfmt loader

"QEMU"

> when binfmt flag O is on.
> Use that and require binfmt flag P as well which will enable QEMU
> to pass in correct argv0 to the application.
> 
> Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
> ---
>  linux-user/main.c           | 13 ++++++++++++-
>  scripts/qemu-binfmt-conf.sh | 36 ++++++++++++++++++------------------
>  2 files changed, 30 insertions(+), 19 deletions(-)
> 
> diff --git a/linux-user/main.c b/linux-user/main.c
> index 71a33c7..9736768 100644
> --- a/linux-user/main.c
> +++ b/linux-user/main.c
> @@ -3829,6 +3829,18 @@ int main(int argc, char **argv, char **envp)
>      int ret;
>      int execfd;
>  
> +    execfd = qemu_getauxval(AT_EXECFD);
> +    if (execfd > 0 ) {

Still one superfluous trailing space.

> +        if (argc < 3) {
> +            fprintf(stderr, "%s: Please use me through binfmt with P flag\n",
> +                    argv[0]);
> +            exit(1);
> +        }
> +        handle_arg_argv0(argv[2]); /* binfmt wrapper */

We might as well inline this for clarity, to distinguish from -0 /
QEMU_ARGV0 handling:

argv0 = strdup(argv[2]);

Also, what is the "binfmt wrapper" comment supposed to say here? Either
extend it, move it or drop it.

> +        memmove(&argv[2], &argv[3], (argc-2)*sizeof(argv));

Still missing spaces around * and - operators.

Why do we need to modify argv[] here when we are building a
target_argv[] further down anyway?

> +        argc--;
> +    }
> +
>      module_call_init(MODULE_INIT_QOM);
>  
>      if ((envlist = envlist_create()) == NULL) {
> @@ -4003,7 +4015,6 @@ int main(int argc, char **argv, char **envp)
>      cpu->opaque = ts;
>      task_settid(ts);
>  
> -    execfd = qemu_getauxval(AT_EXECFD);
>      if (execfd == 0) {
>          execfd = open(filename, O_RDONLY);
>          if (execfd < 0) {
[snip]

Regards,
Andreas
Joakim Tjernlund July 14, 2014, 9:04 p.m. UTC | #2 
Andreas Färber <afaerber@suse.de> wrote on 2014/07/14 22:14:25:
> Am 14.07.2014 20:52, schrieb Joakim Tjernlund:
> > Qemu can autodetect if it is started from Linux binfmt loader
> 
> "QEMU"
> 
> > when binfmt flag O is on.
> > Use that and require binfmt flag P as well which will enable QEMU
> > to pass in correct argv0 to the application.
> > 
> > Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
> > ---
> >  linux-user/main.c           | 13 ++++++++++++-
> >  scripts/qemu-binfmt-conf.sh | 36 ++++++++++++++++++------------------
> >  2 files changed, 30 insertions(+), 19 deletions(-)
> > 
> > diff --git a/linux-user/main.c b/linux-user/main.c
> > index 71a33c7..9736768 100644
> > --- a/linux-user/main.c
> > +++ b/linux-user/main.c
> > @@ -3829,6 +3829,18 @@ int main(int argc, char **argv, char **envp)
> >      int ret;
> >      int execfd;
> > 
> > +    execfd = qemu_getauxval(AT_EXECFD);
> > +    if (execfd > 0 ) {
> 
> Still one superfluous trailing space.
> 
> > +        if (argc < 3) {
> > +            fprintf(stderr, "%s: Please use me through binfmt with P 
flag\n",
> > +                    argv[0]);
> > +            exit(1);
> > +        }
> > +        handle_arg_argv0(argv[2]); /* binfmt wrapper */
> 
> We might as well inline this for clarity, to distinguish from -0 /
> QEMU_ARGV0 handling:
> 
> argv0 = strdup(argv[2]);
> 
> Also, what is the "binfmt wrapper" comment supposed to say here? Either
> extend it, move it or drop it.
> 
> > +        memmove(&argv[2], &argv[3], (argc-2)*sizeof(argv));
> 
> Still missing spaces around * and - operators.
> 
> Why do we need to modify argv[] here when we are building a
> target_argv[] further down anyway?

Because parse_opts() will not do it for me and I cannot figure out how to 
modify
parse_opts() whithout breaking it.
Joakim Tjernlund July 14, 2014, 10:14 p.m. UTC | #3 
Joakim Tjernlund/Transmode wrote on 2014/07/14 23:37:02:

> From: Joakim Tjernlund/Transmode
> To: 
> Cc: Andreas Färber <afaerber@suse.de>, Alexander Graf <agraf@suse.de>, 
qemu-devel@nongnu.org, Riku Voipio <riku.voipio@iki.fi>
> Date: 2014/07/14 23:37
> Subject: Re: [Qemu-devel] [PATCH v2] linux-user: make binfmt flag O 
require P
> 
> Joakim Tjernlund/Transmode wrote on 2014/07/14 23:04:51:
> > > Why do we need to modify argv[] here when we are building a
> > > target_argv[] further down anyway?

> > Because parse_opts() will not do it for me and I cannot figure out how 
to modify
> > parse_opts() whithout breaking it.
> 
> I took another look and now I came up with:
> 
> From 886985747369947e3b28d7a5fb807abd4beae10c Mon Sep 17 00:00:00 2001
> From: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
> Date: Mon, 14 Jul 2014 20:17:28 +0200
> Subject: [PATCH] linux-user: make binfmt flag O require P
> 
> QEMU can autodetect if it is started from Linux binfmt loader
> when binfmt flag O is on.
> Use that and require binfmt flag P as well which will enable QEMU
> to pass in correct argv0 to the application.
> 
> Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
> ---
>  linux-user/main.c           | 16 +++++++++++++---
>  scripts/qemu-binfmt-conf.sh | 36 ++++++++++++++++++------------------
>  2 files changed, 31 insertions(+), 21 deletions(-)
> 
> diff --git a/linux-user/main.c b/linux-user/main.c
> index 71a33c7..845d4e3 100644
> --- a/linux-user/main.c
> +++ b/linux-user/main.c
> @@ -3750,7 +3750,7 @@ static void usage(void)
>      exit(1);
>  }
> 
> -static int parse_args(int argc, char **argv)
> +static int parse_args(int argc, char **argv, int assume_P_flag)
>  {
>      const char *r;
>      int optind;
> @@ -3768,6 +3768,16 @@ static int parse_args(int argc, char **argv)
>      }
> 
>      optind = 1;
> +    if (assume_P_flag) {
> +        /* Assume binfmt P flag is set */
> +        if (argc < 3) {
> +            fprintf(stderr, "%s: Please use me through binfmt with P 
flag\n",
> +                    argv[0]);
> +            exit(1);
> +        }
> +        argv0 = strdup(argv[2]);
> +        optind++;
> +    }

Well, that broke as soon as logged into my LXC. This works though:
 if (assume_P_flag) {
        /* Assume binfmt P flag is set */
        if (argc < 3) {
            fprintf(stderr, "%s: Please use me through binfmt with P 
flag\n",
                    argv[0]);
            exit(1);
        }
        filename = argv[optind];
        exec_path = argv[optind];
        optind++;
        argv0 = strdup(argv[2]);
        return optind;
    }
Are you happy with that?

 Jocke
diff mbox

Patch

diff --git a/linux-user/main.c b/linux-user/main.c
index 71a33c7..9736768 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -3829,6 +3829,18 @@  int main(int argc, char **argv, char **envp)
     int ret;
     int execfd;
 
+    execfd = qemu_getauxval(AT_EXECFD);
+    if (execfd > 0 ) {
+        if (argc < 3) {
+            fprintf(stderr, "%s: Please use me through binfmt with P flag\n",
+                    argv[0]);
+            exit(1);
+        }
+        handle_arg_argv0(argv[2]); /* binfmt wrapper */
+        memmove(&argv[2], &argv[3], (argc-2)*sizeof(argv));
+        argc--;
+    }
+
     module_call_init(MODULE_INIT_QOM);
 
     if ((envlist = envlist_create()) == NULL) {
@@ -4003,7 +4015,6 @@  int main(int argc, char **argv, char **envp)
     cpu->opaque = ts;
     task_settid(ts);
 
-    execfd = qemu_getauxval(AT_EXECFD);
     if (execfd == 0) {
         execfd = open(filename, O_RDONLY);
         if (execfd < 0) {
diff --git a/scripts/qemu-binfmt-conf.sh b/scripts/qemu-binfmt-conf.sh
index 289b1a3..36fcb8f 100644
--- a/scripts/qemu-binfmt-conf.sh
+++ b/scripts/qemu-binfmt-conf.sh
@@ -31,42 +31,42 @@  esac
 
 # register the interpreter for each cpu except for the native one
 if [ $cpu != "i386" ] ; then
-    echo ':i386:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x03\x00:\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-i386:' > /proc/sys/fs/binfmt_misc/register
-    echo ':i486:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x06\x00:\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-i386:' > /proc/sys/fs/binfmt_misc/register
+    echo ':i386:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x03\x00:\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-i386:PO' > /proc/sys/fs/binfmt_misc/register
+    echo ':i486:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x06\x00:\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-i386:PO' > /proc/sys/fs/binfmt_misc/register
 fi
 if [ $cpu != "alpha" ] ; then
-    echo ':alpha:M::\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x26\x90:\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-alpha:' > /proc/sys/fs/binfmt_misc/register
+    echo ':alpha:M::\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x26\x90:\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-alpha:PO' > /proc/sys/fs/binfmt_misc/register
 fi
 if [ $cpu != "arm" ] ; then
-    echo   ':arm:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x28\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-arm:' > /proc/sys/fs/binfmt_misc/register
-    echo   ':armeb:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x28:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-armeb:' > /proc/sys/fs/binfmt_misc/register
+    echo   ':arm:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x28\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-arm:PO' > /proc/sys/fs/binfmt_misc/register
+    echo   ':armeb:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x28:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-armeb:PO' > /proc/sys/fs/binfmt_misc/register
 fi
 if [ $cpu != "aarch64" ] ; then
-    echo ':aarch64:M::\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\xb7\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-aarch64:' > /proc/sys/fs/binfmt_misc/register
+    echo ':aarch64:M::\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\xb7\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-aarch64:PO' > /proc/sys/fs/binfmt_misc/register
 fi
 if [ $cpu != "sparc" ] ; then
-    echo   ':sparc:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x02:\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-sparc:' > /proc/sys/fs/binfmt_misc/register
+    echo   ':sparc:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x02:\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-sparc:PO' > /proc/sys/fs/binfmt_misc/register
 fi
 if [ $cpu != "ppc" ] ; then
-    echo   ':ppc:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x14:\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-ppc:' > /proc/sys/fs/binfmt_misc/register
+    echo   ':ppc:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x14:\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-ppc:PO' > /proc/sys/fs/binfmt_misc/register
 fi
 if [ $cpu != "m68k" ] ; then
     echo   'Please check cpu value and header information for m68k!'
-    echo   ':m68k:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x04:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-m68k:' > /proc/sys/fs/binfmt_misc/register
+    echo   ':m68k:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x04:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-m68k:PO' > /proc/sys/fs/binfmt_misc/register
 fi
 if [ $cpu != "mips" ] ; then
     # FIXME: We could use the other endianness on a MIPS host.
-    echo   ':mips:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-mips:' > /proc/sys/fs/binfmt_misc/register
-    echo   ':mipsel:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-mipsel:' > /proc/sys/fs/binfmt_misc/register
-    echo   ':mipsn32:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-mipsn32:' > /proc/sys/fs/binfmt_misc/register
-    echo   ':mipsn32el:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-mipsn32el:' > /proc/sys/fs/binfmt_misc/register
-    echo   ':mips64:M::\x7fELF\x02\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-mips64:' > /proc/sys/fs/binfmt_misc/register
-    echo   ':mips64el:M::\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-mips64el:' > /proc/sys/fs/binfmt_misc/register
+    echo   ':mips:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-mips:PO' > /proc/sys/fs/binfmt_misc/register
+    echo   ':mipsel:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-mipsel:PO' > /proc/sys/fs/binfmt_misc/register
+    echo   ':mipsn32:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-mipsn32:PO' > /proc/sys/fs/binfmt_misc/register
+    echo   ':mipsn32el:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-mipsn32el:PO' > /proc/sys/fs/binfmt_misc/register
+    echo   ':mips64:M::\x7fELF\x02\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-mips64:PO' > /proc/sys/fs/binfmt_misc/register
+    echo   ':mips64el:M::\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-mips64el:PO' > /proc/sys/fs/binfmt_misc/register
 fi
 if [ $cpu != "sh" ] ; then
-    echo    ':sh4:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x2a\x00:\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-sh4:' > /proc/sys/fs/binfmt_misc/register
-    echo    ':sh4eb:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x2a:\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-sh4eb:' > /proc/sys/fs/binfmt_misc/register
+    echo    ':sh4:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x2a\x00:\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-sh4:PO' > /proc/sys/fs/binfmt_misc/register
+    echo    ':sh4eb:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x2a:\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-sh4eb:PO' > /proc/sys/fs/binfmt_misc/register
 fi
 if [ $cpu != "s390x" ] ; then
-    echo   ':s390x:M::\x7fELF\x02\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x16:\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-s390x:' > /proc/sys/fs/binfmt_misc/register
+    echo   ':s390x:M::\x7fELF\x02\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x16:\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-s390x:PO' > /proc/sys/fs/binfmt_misc/register
 fi