[PATCH] improve xmon symbol lookup

[Anton Blanchard]

> xmon will die reliable in symbol lookup, if the system is broken enough.
>
> This patch makes the lookup optional, E instead of e, T instead of t.

Id love to know where we are locking up. Actually im not sure why we
dont do the following, just wrap the entire kallsyms call with the
__debugger_fault_handler stuff.

Untested patch below.

Anton


===== arch/ppc64/xmon/xmon.c 1.36 vs edited =====
--- 1.36/arch/ppc64/xmon/xmon.c	Fri Feb 27 16:25:16 2004
+++ edited/arch/ppc64/xmon/xmon.c	Thu Mar  4 01:16:49 2004
@@ -191,12 +191,7 @@

 static struct pt_regs *xmon_regs[NR_CPUS];

-void __xmon_print_symbol(const char *fmt, unsigned long address);
-#define xmon_print_symbol(fmt, addr)		\
-do {						\
-	__check_printsym_format(fmt, "");	\
-	__xmon_print_symbol(fmt, addr);		\
-} while(0)
+void xmon_print_symbol(const char *fmt, unsigned long address);

 /*
  * Stuff for reading and writing memory safely
@@ -1974,6 +1969,8 @@
 			else
 				printf("Symbol '%s' not found.\n", tmp);
 			sync();
+			/* wait a little while to see if we get a machine check */
+			__delay(200);
 		}
 		__debugger_fault_handler = 0;
 		termch = 0;
@@ -1981,51 +1978,20 @@
 	}
 }

-
-/* xmon version of __print_symbol */
-void __xmon_print_symbol(const char *fmt, unsigned long address)
+/* xmon version of print_symbol */
+void xmon_print_symbol(const char *fmt, unsigned long address)
 {
-	char *modname;
-	const char *name;
-	unsigned long offset, size;
-
 	if (setjmp(bus_error_jmp) == 0) {
 		__debugger_fault_handler = handle_fault;
 		sync();
-		name = kallsyms_lookup(address, &size, &offset, &modname,
-				       tmpstr);
+
+		print_symbol(fmt, address);
+
 		sync();
 		/* wait a little while to see if we get a machine check */
 		__delay(200);
 	} else {
-		name = "symbol lookup failed";
-	}
-
-	__debugger_fault_handler = 0;
-
-	if (!name) {
-		char addrstr[sizeof("0x%lx") + (BITS_PER_LONG*3/10)];
-
-		sprintf(addrstr, "0x%lx", address);
-		printf(fmt, addrstr);
-		return;
-	}
-
-	if (modname) {
-		/* This is pretty small. */
-		char buffer[sizeof("%s+%#lx/%#lx [%s]")
-			   + strlen(name) + 2*(BITS_PER_LONG*3/10)
-			   + strlen(modname)];
-
-		sprintf(buffer, "%s+%#lx/%#lx [%s]",
-			name, offset, size, modname);
-		printf(fmt, buffer);
-	} else {
-		char buffer[sizeof("%s+%#lx/%#lx")
-			   + strlen(name) + 2*(BITS_PER_LONG*3/10)];
-
-		sprintf(buffer, "%s+%#lx/%#lx", name, offset, size);
-		printf(fmt, buffer);
+		printf("*** symbol lookup failed");
 	}
 }


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