On Fri, Jun 18, 2010 at 10:11 AM, Prasad Joshi <prasadjoshi124@xxxxxxxxx> wrote: > Hi All, > > I am trying to understand a a kernel oops report. Here are some of the > fields from the report > > BUG: unable to handle kernel NULL pointer dereference at 0000000000000034 > Oops: 0000 [#1] SMP > Pid: 6478, comm: cp Tainted: P 2.6.31.5-127.fc12.x86_64 #1 Inspiron 1525 > RIP: 0010:[<ffffffff810faac1>] [<ffffffff810faac1>] do_sys_open+0x7a/0x10f > CR2: 0000000000000034 > > As I know, when a page fault occurs, the address the program attempted to > access is stored in the CR2 register. So probably the pointer is pointing to > address 0034 and is being access. > > The BUG string is bit confusing, it says NULL pointer dereference at 0034, I > know the address 00034 is not valid but why is it interpreted as NULL > pointer? The NULL pointer as I know should point to address 0. As ppl have already mentioned, this is some offset into a structure. Next thing you can try is to do a disas do_sys_open and find out which member/structure is being accessed which has this offset. You can also try to get the assembly instructions from the "code" dumped. if you already have the source code for your running kernel you can also try "l *do_sys_open+0x7a". > > Thanks and Regards, > Prasad > -- Thanks - Manish ================================== [$\*.^ -- I miss being one of them ================================== -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
