On Wed, 2 May 2007 15:50:19 +0530 Nirmal Thacker wrote: > Hello, > > In a kernel related project which I am working on, after compilation I > face certain errors, which I am having difficulty in debugging. The > error is of the form: > > Unable to handle kernel NULL pointer dereference at virtual address 00000006 > current->tss.cr3=1ff88000, %cr3=1ff88000 > *pde=00000000 > Oops:0000 > CPU:0 > EIP:0010:[<c01386a9>] > EFLAGS:00010282 > eax:ffffffe ebz:fffffff2 .............. > ............. > Process init(pid:1, process nr:1 , stackpage=dffcb000) > Stack: ............ (stack listing here) > Call Trace:[<c013873e>][<c0107b70>] > Code: 8b 40 ............. > > I tried debugging this error by examining the EIP in the System.map > file and found it to be a function , part of my code. However that > function did not dereference any NULL pointer. > The call trace values too, when examined showed no NULL pointer dereference. NULL pointer in this context actually means between 0 and PAGE_SIZE - 1, i.e., somewhere in the 0-th page of the address space. And the message tells us that it was at address 00000006 (hex). So I would be suspecting something in your function. > I are working on the 2.2.15 kernel and installed a KALLSYMS patch but > we there was no stack listing as well. Why? :( > I am aware that the above information is not enough but if some one > could help me out i'd be glad to pass the code entirely . Yes, please post the source code to the mailing list. --- ~Randy *** Remember to use Documentation/SubmitChecklist when testing your code *** -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
