debuginfo search path in i386 and powerpc are different

[Srikar Dronamraju]

Hi Roland, 

> Please give more details in your report.  Exactly which files exist on each
> of your systems?  Specify which of those are which kind of file: unstripped
> vmlinux, stripped vmlinux, separate debuginfo file from vmlinux.


On Powerpc 
-----------
On my setup I copied the unstripped vmlinux to
/lib/modules/2.6.18-rhel5.1snap2/vmlinux and the stripped vmlinux to
/boot/vmlinux-2.6.18-rhel5.1snap2. 

The output of 
sudo strace -o a.strace stap newmodpup.stp; grep open a.strace|grep vmlin
is as follows.

open("/boot/vmlinux-2.6.18-rhel5.1snap2", O_RDONLY|O_LARGEFILE) = 3
open("/boot/vmlinux-2.6.18-rhel5.1snap2.debug", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/boot/.debug/vmlinux-2.6.18-rhel5.1snap2.debug", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/usr/lib/debug/boot/vmlinux-2.6.18-rhel5.1snap2.debug", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)


As I said earlier, /boot/vmlinux-2.6.18-rhel5.1snap2 is a stripped
kernel. 


I further copied /usr/lib/debug/boot/vmlinux-2.6.18-rhel5.1snap2.debug
to /lib/modules/2.6.18-rhel5.1snap2/vmlinux and repeated the same
procedure. 

The output is as below: 

open("/boot/vmlinux-2.6.18-rhel5.1snap2", O_RDONLY|O_LARGEFILE) = 3
open("/boot/vmlinux-2.6.18-rhel5.1snap2.debug", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/boot/.debug/vmlinux-2.6.18-rhel5.1snap2.debug", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/usr/lib/debug/boot/vmlinux-2.6.18-rhel5.1snap2.debug", O_RDONLY|O_LARGEFILE) = 4

Here /boot/vmlinux-2.6.18-rhel5.1snap2 is stripped and
/usr/lib/debug/boot/vmlinux-2.6.18-rhel5.1snap2.debug is unstripped. 


On i386 (kernel being /boot/vmlinux-2.6.18-rhel5.1snap2)
--------- 
On this setup also I copied the unstripped vmlinux to
/lib/modules/2.6.18-rhel5.1snap2/vmlinux and the stripped vmlinux to
/boot/vmlinuz-2.6.18-rhel5.1snap2. 

The output of 
sudo strace -o a.strace stap newmodpup.stp; grep open a.strace|grep vmlin
is as follows.

open("/boot/vmlinux-2.6.18-rhel5.1snap2", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/boot/vmlinux-2.6.18-rhel5.1snap2", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/boot/.debug/vmlinux-2.6.18-rhel5.1snap2", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/usr/lib/debug/boot/vmlinux-2.6.18-rhel5.1snap2", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/boot/vmlinux-2.6.18-rhel5.1snap2.debug", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/boot/.debug/vmlinux-2.6.18-rhel5.1snap2.debug", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/usr/lib/debug/boot/vmlinux-2.6.18-rhel5.1snap2.debug", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/lib/modules/2.6.18-rhel5.1snap2/vmlinux", O_RDONLY|O_LARGEFILE) = 3
open("/lib/modules/2.6.18-rhel5.1snap2/vmlinux.debug", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/lib/modules/2.6.18-rhel5.1snap2/.debug/vmlinux.debug", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
open("/usr/lib/debug/lib/modules/2.6.18-rhel5.1snap2/vmlinux.debug", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)

Here /lib/modules/2.6.18-rhel5.1snap2/vmlinux is the unstripped vmlinux
file and systemtap identifies it correctly.


Do let me know if you want me to provide any other input. 

--
Thanks and Regards
Srikar