I selected the gcov option during the compiler of uml and success.  When I halt the uml, I also got the *.gcba files. But
when I used the gcov tool to get the coverage of the code file, the problems occured as follow:
[root@umltest kernel]# gcov sched.c
File `kernel/sched.c'
Lines executed:52.44% of 965
kernel/sched.c:creating `sched.c.gcov'
kernel/sched.c:cannot open source file
File `include/linux/list.h'
Lines executed:90.48% of 21
include/linux/list.h:creating `list.h.gcov'
include/linux/list.h:cannot open source file
File `include/asm/arch/bitops.h'
Lines executed:100.00% of 21
include/asm/arch/bitops.h:creating `bitops.h.gcov'
include/asm/arch/bitops.h:cannot open source file
Any body can tell me why, my kernel version is   2.6.12.

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