show_trace(&stack); 
show_trace(current, &stack); 
void dump_stack(void){	unsigned long stack;	show_trace(&stack);}
4520	/local/tlutelli/issta_data/temp/c/2005_temp/2005/4520/b3461034d7d46455060c8476910be22b6b0fc313/sysrq.c/buggy/arch/um/kernel/sysrq.c