Re: strace on Linux/MIPS?

[Ralf Baechle <ralf@oss.sgi.com>]

On Fri, Jul 28, 2000 at 01:51:39PM +0200, Wichert Akkerman wrote:

> Previously Ralf Baechle wrote:
> > Looks like strace is still tryping to copy mmap_arg_struct like on Intel
> > but on MIPS we don't use that?
> 
> Could be, I think MIPS and i386 use the same codepath there. Patches
> are appreciated so I can include them in strace 4.3 (eta 3 weeks from
> now)

Here's the second strace patch, please apply.

I noticed that process.c:change_syscall() can't work as is - the all kernels
would change the v0 register - and happily use the old value that is take
the wrong syscall.  A kernel buglet which also hits the usermode kernel
and which I'll fix asap.

  Ralf

--- strace/process.c.orig	Fri Jul 28 23:37:14 2000
+++ strace/process.c	Fri Jul 28 23:33:43 2000
@@ -502,6 +502,24 @@
 		if (errno)
 			return -1;
 	}
+#elif defined(MIPS)
+	{
+		errno = 0;
+		if (argnum < 4)
+			ptrace(PTRACE_POKEUSER, tcp->pid,
+			       (char*)(REG_A0 + argnum), tcp->u_arg[argnum]);
+		else {
+			unsigned long *sp;
+
+			if (upeek(tcp->pid, REG_SP, (long *) &sp) , 0)
+				return -1;
+
+			ptrace(PTRACE_POKEDATA, tcp->pid,
+			       (char*)(sp + argnum - 4), tcp->u_arg[argnum]);
+		}
+		if (errno)
+			return -1;
+	}
 #else
 # warning Sorry, setargs not implemented for this architecture.
 #endif