2.0.x GPF

ganesh@cse.iitb.ernet.in
Tue, 2 Jun 1998 15:37:53 +0530 (IST)


hi,
I just installed 34pre16 on a Pentium and ran my 2.1.103 vmlinux (sic)
on it.
[ganesh@ganesh-pc ganesh]$ /home/linux/vmlinux
general protection: 0000
CPU: 0
EIP: 0010:[<0010a6d1>]
EFLAGS: 00010202
eax: 00000000 ebx: 0809a3c0 ecx: 0809a2c0 edx: 00000000
esi: 0809a2c0 edi: bffffc5c ebp: bffffbf8 esp: 011e6fec
ds: 002b es: 002b fs: 002b gs: 002b ss: 0018
Process vmlinux (pid: 871, process nr: 28, stackpage=011e6000)
Stack: c0100000 00000023 00000206 bffffe14 0000002b
Call Trace:
Code: cf 89 f6 89 e1 51 f7 41 38 00 00 02 00 75 2c 53 e8 de fb ff
Segmentation fault
[ganesh@ganesh-pc ganesh]$

Relevant part of klogd output:
Jun 2 14:17:21 ganesh-pc kernel: EIP: 0010:[ret_from_sys_call+133/136]

And if I run the same /home/linux/vmlinux from gdb it faults with :
Jun 2 14:17:29 ganesh-pc kernel: general protection: 0000
Jun 2 14:17:29 ganesh-pc kernel: CPU: 0
Jun 2 14:17:29 ganesh-pc kernel: EIP: 0010:[signal_return+55/56]
Jun 2 14:17:29 ganesh-pc kernel: EFLAGS: 00010202
Jun 2 14:17:29 ganesh-pc kernel: eax: 00000000 ebx: 08097818 ecx: 080977f0
edx: 00000000
Jun 2 14:17:29 ganesh-pc kernel: esi: 080977f0 edi: 08096f28 ebp: bffffa94
esp: 01218fec
Jun 2 14:17:29 ganesh-pc kernel: ds: 002b es: 002b fs: 002b gs: 002b ss: 0018
Jun 2 14:17:29 ganesh-pc kernel: Process vmlinux (pid: 728, process nr: 34, stackpage=01218000)
Jun 2 14:17:29 ganesh-pc kernel: Stack: c0100000 00000023 00000206 bffffe5c 0000002b
Jun 2 14:17:29 ganesh-pc kernel: Call Trace:
Jun 2 14:17:29 ganesh-pc kernel: Code: cf e8 3f 26 00 00 89 c4 50 53 e8 aa fb ff ff 5b 5b 66 83 7c

In both cases, the offending opcode is an iret.

Running the pre34 vmlinux gives the expected SEGV. Ditto for 2.1.103 running
any vmlinux.
It is 100% reproducible. I also tried it on a P-II running 2.0.32 with
a 2.1.101 vmlinux and it gave exactly the same behaviour down to the
faulting point. So I guess it is a fairly old bug.

-- ganesh

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu