aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorArnd Bergmann <arnd@arndb.de>2006-10-02 02:18:34 -0700
committerLinus Torvalds <torvalds@g5.osdl.org>2006-10-02 07:57:23 -0700
commitfe74290d51bc08e9b90ed7c145d74a22cd50b90e (patch)
treebec3a117a95a1ace6dba6a76b3edbd6297d40b63
parent3db03b4afb3ecd66a0399b8ba57742ca953b0ecd (diff)
downloadlinux-2.6.34-ux500-fe74290d51bc08e9b90ed7c145d74a22cd50b90e.tar.gz
[PATCH] provide kernel_execve on all architectures
This adds the new kernel_execve function on all architectures that were using _syscall3() to implement execve. The implementation uses code from the _syscall3 macros provided in the unistd.h header file. I don't have cross-compilers for any of these architectures, so the patch is untested with the exception of i386. Most architectures can probably implement this in a nicer way in assembly or by combining it with the sys_execve implementation itself, but this should do it for now. [bunk@stusta.de: m68knommu build fix] [markh@osdl.org: build fix] [bero@arklinux.org: build fix] [ralf@linux-mips.org: mips fix] [schwidefsky@de.ibm.com: s390 fix] Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Andi Kleen <ak@muc.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ian Molton <spyro@f2s.com> Cc: Mikael Starvik <starvik@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Hirokazu Takata <takata.hirokazu@renesas.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Richard Curnow <rc@rc0.org.uk> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp> Cc: Chris Zankel <chris@zankel.net> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Bernhard Rosenkraenzer <bero@arklinux.org> Signed-off-by: Mark Haverkamp <markh@osdl.org> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r--arch/frv/kernel/Makefile2
-rw-r--r--arch/frv/kernel/kernel_execve.S33
-rw-r--r--arch/h8300/kernel/sys_h8300.c24
-rw-r--r--arch/i386/kernel/sys_i386.c15
-rw-r--r--arch/m32r/kernel/sys_m32r.c20
-rw-r--r--arch/m68k/kernel/sys_m68k.c16
-rw-r--r--arch/m68knommu/kernel/sys_m68k.c15
-rw-r--r--arch/mips/kernel/syscall.c29
-rw-r--r--arch/ppc/kernel/misc.S18
-rw-r--r--arch/s390/kernel/sys_s390.c20
-rw-r--r--arch/sh/kernel/sys_sh.c17
-rw-r--r--arch/sh64/kernel/sys_sh64.c19
-rw-r--r--arch/sparc/kernel/sys_sparc.c23
-rw-r--r--arch/sparc64/kernel/sys_sparc.c21
-rw-r--r--arch/v850/kernel/syscalls.c20
-rw-r--r--arch/xtensa/kernel/syscalls.c20
16 files changed, 300 insertions, 12 deletions
diff --git a/arch/frv/kernel/Makefile b/arch/frv/kernel/Makefile
index 32db3499c46..e8f73ed28b5 100644
--- a/arch/frv/kernel/Makefile
+++ b/arch/frv/kernel/Makefile
@@ -8,7 +8,7 @@ heads-$(CONFIG_MMU) := head-mmu-fr451.o
extra-y:= head.o init_task.o vmlinux.lds
obj-y := $(heads-y) entry.o entry-table.o break.o switch_to.o kernel_thread.o \
- process.o traps.o ptrace.o signal.o dma.o \
+ kernel_execve.o process.o traps.o ptrace.o signal.o dma.o \
sys_frv.o time.o semaphore.o setup.o frv_ksyms.o \
debug-stub.o irq.o sleep.o uaccess.o
diff --git a/arch/frv/kernel/kernel_execve.S b/arch/frv/kernel/kernel_execve.S
new file mode 100644
index 00000000000..9b074a16a05
--- /dev/null
+++ b/arch/frv/kernel/kernel_execve.S
@@ -0,0 +1,33 @@
+/* in-kernel program execution
+ *
+ * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/linkage.h>
+#include <asm/unistd.h>
+
+###############################################################################
+#
+# Do a system call from kernel instead of calling sys_execve so we end up with
+# proper pt_regs.
+#
+# int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+#
+# On entry: GR8/GR9/GR10: arguments to function
+# On return: GR8: syscall return.
+#
+###############################################################################
+ .globl kernel_execve
+ .type kernel_execve,@function
+kernel_execve:
+ setlos __NR_execve,gr7
+ tira gr0,#0
+ bralr
+
+ .size kernel_execve,.-kernel_execve
diff --git a/arch/h8300/kernel/sys_h8300.c b/arch/h8300/kernel/sys_h8300.c
index 0f61b7ad69a..302a2dfe634 100644
--- a/arch/h8300/kernel/sys_h8300.c
+++ b/arch/h8300/kernel/sys_h8300.c
@@ -25,6 +25,7 @@
#include <asm/cachectl.h>
#include <asm/traps.h>
#include <asm/ipc.h>
+#include <asm/unistd.h>
/*
* sys_pipe() is the normal C calling standard for creating
@@ -280,3 +281,26 @@ asmlinkage void syscall_print(void *dummy,...)
((regs->pc)&0xffffff)-2,regs->orig_er0,regs->er1,regs->er2,regs->er3,regs->er0);
}
#endif
+
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+ register long res __asm__("er0");
+ register const char * _a __asm__("er1") = filename;
+ register void *_b __asm__("er2") = argv;
+ register void *_c __asm__("er3") = envp;
+ __asm__ __volatile__ ("mov.l %1,er0\n\t"
+ "trapa #0\n\t"
+ : "=r" (res)
+ : "g" (__NR_execve),
+ "g" (_a),
+ "g" (_b),
+ "g" (_c)
+ : "cc", "memory");
+ return res;
+}
+
+
diff --git a/arch/i386/kernel/sys_i386.c b/arch/i386/kernel/sys_i386.c
index dc6e3bbeba3..4048397f174 100644
--- a/arch/i386/kernel/sys_i386.c
+++ b/arch/i386/kernel/sys_i386.c
@@ -21,6 +21,7 @@
#include <linux/utsname.h>
#include <asm/uaccess.h>
+#include <asm/unistd.h>
#include <asm/ipc.h>
/*
@@ -248,3 +249,17 @@ asmlinkage int sys_olduname(struct oldold_utsname __user * name)
return error;
}
+
+
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+ long __res;
+ asm volatile ("push %%ebx ; movl %2,%%ebx ; int $0x80 ; pop %%ebx"
+ : "=a" (__res)
+ : "0" (__NR_execve),"ri" (filename),"c" (argv), "d" (envp) : "memory");
+ return __res;
+}
diff --git a/arch/m32r/kernel/sys_m32r.c b/arch/m32r/kernel/sys_m32r.c
index 7c29396cc67..b567351f3c5 100644
--- a/arch/m32r/kernel/sys_m32r.c
+++ b/arch/m32r/kernel/sys_m32r.c
@@ -25,6 +25,8 @@
#include <asm/cachectl.h>
#include <asm/cacheflush.h>
#include <asm/ipc.h>
+#include <asm/syscall.h>
+#include <asm/unistd.h>
/*
* sys_tas() - test-and-set
@@ -223,3 +225,21 @@ asmlinkage int sys_cachectl(char *addr, int nbytes, int op)
return -ENOSYS;
}
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+ register long __scno __asm__ ("r7") = __NR_execve;
+ register long __arg3 __asm__ ("r2") = (long)(envp);
+ register long __arg2 __asm__ ("r1") = (long)(argv);
+ register long __res __asm__ ("r0") = (long)(filename);
+ __asm__ __volatile__ (
+ "trap #" SYSCALL_VECTOR "|| nop"
+ : "=r" (__res)
+ : "r" (__scno), "0" (__res), "r" (__arg2),
+ "r" (__arg3)
+ : "memory");
+ return __res;
+}
diff --git a/arch/m68k/kernel/sys_m68k.c b/arch/m68k/kernel/sys_m68k.c
index 143c552d38f..90238a8c9e1 100644
--- a/arch/m68k/kernel/sys_m68k.c
+++ b/arch/m68k/kernel/sys_m68k.c
@@ -27,6 +27,7 @@
#include <asm/traps.h>
#include <asm/ipc.h>
#include <asm/page.h>
+#include <asm/unistd.h>
/*
* sys_pipe() is the normal C calling standard for creating
@@ -663,3 +664,18 @@ asmlinkage int sys_getpagesize(void)
{
return PAGE_SIZE;
}
+
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+ register long __res asm ("%d0") = __NR_execve;
+ register long __a asm ("%d1") = (long)(filename);
+ register long __b asm ("%d2") = (long)(argv);
+ register long __c asm ("%d3") = (long)(envp);
+ asm volatile ("trap #0" : "+d" (__res)
+ : "d" (__a), "d" (__b), "d" (__c));
+ return __res;
+}
diff --git a/arch/m68knommu/kernel/sys_m68k.c b/arch/m68knommu/kernel/sys_m68k.c
index d87e1e0a133..c3494b8447d 100644
--- a/arch/m68knommu/kernel/sys_m68k.c
+++ b/arch/m68knommu/kernel/sys_m68k.c
@@ -26,6 +26,7 @@
#include <asm/traps.h>
#include <asm/ipc.h>
#include <asm/cacheflush.h>
+#include <asm/unistd.h>
/*
* sys_pipe() is the normal C calling standard for creating
@@ -206,3 +207,17 @@ asmlinkage int sys_getpagesize(void)
return PAGE_SIZE;
}
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+ register long __res asm ("%d0") = __NR_execve;
+ register long __a asm ("%d1") = (long)(filename);
+ register long __b asm ("%d2") = (long)(argv);
+ register long __c asm ("%d3") = (long)(envp);
+ asm volatile ("trap #0" : "+d" (__res)
+ : "d" (__a), "d" (__b), "d" (__c));
+ return __res;
+}
diff --git a/arch/mips/kernel/syscall.c b/arch/mips/kernel/syscall.c
index 970e3e96b1d..26e1a7e78d1 100644
--- a/arch/mips/kernel/syscall.c
+++ b/arch/mips/kernel/syscall.c
@@ -406,3 +406,32 @@ asmlinkage void bad_stack(void)
{
do_exit(SIGSEGV);
}
+
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+ register unsigned long __a0 asm("$4") = (unsigned long) filename;
+ register unsigned long __a1 asm("$5") = (unsigned long) argv;
+ register unsigned long __a2 asm("$6") = (unsigned long) envp;
+ register unsigned long __a3 asm("$7");
+ unsigned long __v0;
+
+ __asm__ volatile (" \n"
+ " .set noreorder \n"
+ " li $2, %5 # __NR_execve \n"
+ " syscall \n"
+ " move %0, $2 \n"
+ " .set reorder \n"
+ : "=&r" (__v0), "=r" (__a3)
+ : "r" (__a0), "r" (__a1), "r" (__a2), "i" (__NR_execve)
+ : "$2", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24",
+ "memory");
+
+ if (__a3 == 0)
+ return __v0;
+
+ return -__v0;
+}
diff --git a/arch/ppc/kernel/misc.S b/arch/ppc/kernel/misc.S
index 50b4bbd0680..5f6684012de 100644
--- a/arch/ppc/kernel/misc.S
+++ b/arch/ppc/kernel/misc.S
@@ -942,20 +942,16 @@ _GLOBAL(kernel_thread)
addi r1,r1,16
blr
+_GLOBAL(kernel_execve)
+ li r0,__NR_execve
+ sc
+ bnslr
+ neg r3,r3
+ blr
+
/*
* This routine is just here to keep GCC happy - sigh...
*/
_GLOBAL(__main)
blr
-#define SYSCALL(name) \
-_GLOBAL(name) \
- li r0,__NR_##name; \
- sc; \
- bnslr; \
- lis r4,errno@ha; \
- stw r3,errno@l(r4); \
- li r3,-1; \
- blr
-
-SYSCALL(execve)
diff --git a/arch/s390/kernel/sys_s390.c b/arch/s390/kernel/sys_s390.c
index e351780bb66..584ed95f338 100644
--- a/arch/s390/kernel/sys_s390.c
+++ b/arch/s390/kernel/sys_s390.c
@@ -27,6 +27,7 @@
#include <linux/file.h>
#include <linux/utsname.h>
#include <linux/personality.h>
+#include <linux/unistd.h>
#include <asm/uaccess.h>
#include <asm/ipc.h>
@@ -266,3 +267,22 @@ s390_fadvise64_64(struct fadvise64_64_args __user *args)
return sys_fadvise64_64(a.fd, a.offset, a.len, a.advice);
}
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+ register const char *__arg1 asm("2") = filename;
+ register char *const*__arg2 asm("3") = argv;
+ register char *const*__arg3 asm("4") = envp;
+ register long __svcres asm("2");
+ asm volatile(
+ "svc %b1"
+ : "=d" (__svcres)
+ : "i" (__NR_execve),
+ "0" (__arg1),
+ "d" (__arg2),
+ "d" (__arg3) : "memory");
+ return __svcres;
+}
diff --git a/arch/sh/kernel/sys_sh.c b/arch/sh/kernel/sys_sh.c
index 11c2acde6ea..8fde95001c3 100644
--- a/arch/sh/kernel/sys_sh.c
+++ b/arch/sh/kernel/sys_sh.c
@@ -25,6 +25,7 @@
#include <asm/cacheflush.h>
#include <asm/uaccess.h>
#include <asm/ipc.h>
+#include <asm/unistd.h>
/*
* sys_pipe() is the normal C calling standard for creating
@@ -309,3 +310,19 @@ asmlinkage int sys_fadvise64_64_wrapper(int fd, u32 offset0, u32 offset1,
(u64)len0 << 32 | len1, advice);
#endif
}
+
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+ register long __sc0 __asm__ ("r3") = __NR_execve;
+ register long __sc4 __asm__ ("r4") = (long) filename;
+ register long __sc5 __asm__ ("r5") = (long) argv;
+ register long __sc6 __asm__ ("r6") = (long) envp;
+ __asm__ __volatile__ ("trapa #0x13" : "=z" (__sc0)
+ : "0" (__sc0), "r" (__sc4), "r" (__sc5), "r" (__sc6)
+ : "memory");
+ return __sc0;
+}
diff --git a/arch/sh64/kernel/sys_sh64.c b/arch/sh64/kernel/sys_sh64.c
index c6de1a95af4..ad0fa4e003e 100644
--- a/arch/sh64/kernel/sys_sh64.c
+++ b/arch/sh64/kernel/sys_sh64.c
@@ -32,6 +32,7 @@
#include <asm/uaccess.h>
#include <asm/ipc.h>
#include <asm/ptrace.h>
+#include <asm/unistd.h>
#define REG_3 3
@@ -283,3 +284,21 @@ asmlinkage int sys_uname(struct old_utsname * name)
up_read(&uts_sem);
return err?-EFAULT:0;
}
+
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+ register unsigned long __sc0 __asm__ ("r9") = ((0x13 << 16) | __NR_execve);
+ register unsigned long __sc2 __asm__ ("r2") = (unsigned long) filename;
+ register unsigned long __sc3 __asm__ ("r3") = (unsigned long) argv;
+ register unsigned long __sc4 __asm__ ("r4") = (unsigned long) envp;
+ __asm__ __volatile__ ("trapa %1 !\t\t\t execve(%2,%3,%4)"
+ : "=r" (__sc0)
+ : "r" (__sc0), "r" (__sc2), "r" (__sc3), "r" (__sc4) );
+ __asm__ __volatile__ ("!dummy %0 %1 %2 %3"
+ : : "r" (__sc0), "r" (__sc2), "r" (__sc3), "r" (__sc4) : "memory");
+ return __sc0;
+}
diff --git a/arch/sparc/kernel/sys_sparc.c b/arch/sparc/kernel/sys_sparc.c
index 002ab4dbe5c..a954a0c0000 100644
--- a/arch/sparc/kernel/sys_sparc.c
+++ b/arch/sparc/kernel/sys_sparc.c
@@ -24,6 +24,7 @@
#include <asm/uaccess.h>
#include <asm/ipc.h>
+#include <asm/unistd.h>
/* #define DEBUG_UNIMP_SYSCALL */
@@ -488,3 +489,25 @@ out:
up_read(&uts_sem);
return err;
}
+
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+ long __res;
+ register long __g1 __asm__ ("g1") = __NR_execve;
+ register long __o0 __asm__ ("o0") = (long)(filename);
+ register long __o1 __asm__ ("o1") = (long)(argv);
+ register long __o2 __asm__ ("o2") = (long)(envp);
+ asm volatile ("t 0x10\n\t"
+ "bcc 1f\n\t"
+ "mov %%o0, %0\n\t"
+ "sub %%g0, %%o0, %0\n\t"
+ "1:\n\t"
+ : "=r" (__res), "=&r" (__o0)
+ : "1" (__o0), "r" (__o1), "r" (__o2), "r" (__g1)
+ : "cc");
+ return __res;
+}
diff --git a/arch/sparc64/kernel/sys_sparc.c b/arch/sparc64/kernel/sys_sparc.c
index 89ac435aacc..a53d4abb4b4 100644
--- a/arch/sparc64/kernel/sys_sparc.c
+++ b/arch/sparc64/kernel/sys_sparc.c
@@ -31,6 +31,7 @@
#include <asm/utrap.h>
#include <asm/perfctr.h>
#include <asm/a.out.h>
+#include <asm/unistd.h>
/* #define DEBUG_UNIMP_SYSCALL */
@@ -963,3 +964,23 @@ asmlinkage long sys_perfctr(int opcode, unsigned long arg0, unsigned long arg1,
};
return err;
}
+
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+ long __res;
+ register long __g1 __asm__ ("g1") = __NR_execve;
+ register long __o0 __asm__ ("o0") = (long)(filename);
+ register long __o1 __asm__ ("o1") = (long)(argv);
+ register long __o2 __asm__ ("o2") = (long)(envp);
+ asm volatile ("t 0x6d\n\t"
+ "sub %%g0, %%o0, %0\n\t"
+ "movcc %%xcc, %%o0, %0\n\t"
+ : "=r" (__res), "=&r" (__o0)
+ : "1" (__o0), "r" (__o1), "r" (__o2), "r" (__g1)
+ : "cc");
+ return __res;
+}
diff --git a/arch/v850/kernel/syscalls.c b/arch/v850/kernel/syscalls.c
index 2ec0700fc46..d2b1fb19d24 100644
--- a/arch/v850/kernel/syscalls.c
+++ b/arch/v850/kernel/syscalls.c
@@ -33,6 +33,7 @@
#include <asm/uaccess.h>
#include <asm/ipc.h>
#include <asm/semaphore.h>
+#include <asm/unistd.h>
/*
* sys_ipc() is the de-multiplexer for the SysV IPC calls..
@@ -194,3 +195,22 @@ unsigned long sys_mmap (unsigned long addr, size_t len,
out:
return err;
}
+
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+ register char *__a __asm__ ("r6") = filename;
+ register void *__b __asm__ ("r7") = argv;
+ register void *__c __asm__ ("r8") = envp;
+ register unsigned long __syscall __asm__ ("r12") = __NR_execve;
+ register unsigned long __ret __asm__ ("r10");
+ __asm__ __volatile__ ("trap 0"
+ : "=r" (__ret), "=r" (__syscall)
+ : "1" (__syscall), "r" (__a), "r" (__b), "r" (__c)
+ : "r1", "r5", "r11", "r13", "r14",
+ "r15", "r16", "r17", "r18", "r19");
+ return __ret;
+}
diff --git a/arch/xtensa/kernel/syscalls.c b/arch/xtensa/kernel/syscalls.c
index 37c90ca5b98..d9285d4d556 100644
--- a/arch/xtensa/kernel/syscalls.c
+++ b/arch/xtensa/kernel/syscalls.c
@@ -266,3 +266,23 @@ void system_call (struct pt_regs *regs)
regs->areg[2] = res;
do_syscall_trace();
}
+
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+ long __res;
+ asm volatile (
+ " mov a5, %2 \n"
+ " mov a4, %4 \n"
+ " mov a3, %3 \n"
+ " movi a2, %1 \n"
+ " syscall \n"
+ " mov %0, a2 \n"
+ : "=a" (__res)
+ : "i" (__NR_execve), "a" (filename), "a" (argv), "a" (envp)
+ : "a2", "a3", "a4", "a5");
+ return __res;
+}