Why RHEL 5 system crashes on "RIP: __link_path_walk+0x54/0xf42" ?

Issue

• Server kernel panic on 'RIP: __link_path_walk+0x54/0xf42' with following call traces:

Unable to handle kernel NULL pointer dereference at 00000000000000e8 RIP: 
 [<ffffffff800095c6>] __link_path_walk+0x54/0xf42
....
RIP: 0010:[<ffffffff800095c6>]  [<ffffffff800095c6>] __link_path_walk+0x54/0xf42
....
Call Trace:
 [<ffffffff8000e782>] link_path_walk+0x5c/0xe5
 [<ffffffff800668a2>] do_page_fault+0x4fe/0x830
 [<ffffffff8000c965>] do_path_lookup+0x270/0x2e8
 [<ffffffff800122eb>] getname+0x15b/0x1c1
 [<ffffffff80023700>] __user_walk_fd+0x37/0x4c
 [<ffffffff80028617>] vfs_stat_fd+0x1b/0x4a
 [<ffffffff800668a2>] do_page_fault+0x4fe/0x830
 [<ffffffff80023432>] sys_newstat+0x19/0x31
 [<ffffffff8005d229>] tracesys+0x71/0xe0
 [<ffffffff8005d28d>] tracesys+0xd5/0xe0

Code: 49 8b 84 24 e8 00 00 00 41 8b 5c 24 4c 48 85 c0 74 0b 48 83 
RIP  [<ffffffff800095c6>] __link_path_walk+0x54/0xf42
 RSP <ffff81001a09dca8>