Hello, I'm running Linux 2.4.27 i686 single-processor from debian's kernel-source-2.4.27 and mdadm 1.9.0 in monitor mode: /sbin/mdadm -F -i /var/run/mdadm.pid -m raid -f -s While stopping a raid1 (raidstop /dev/md8) it seems there occured some race. I don't know if this is a known issue, if so, sorry for the long report :) The oops: md: marking sb clean... md: updating md8 RAID superblock on device md: hde1 [events: 0000000a]<6>(write) hde1's sb offset: 195358336 Unable to handle kernel NULL pointer dereference at virtual address 000003d8 printing eip: c024be53 *pde = 00000000 Oops: 0000 CPU: 0 EIP: 0010:[<c024be53>] Not tainted EFLAGS: 00010286 eax: c1c149ac ebx: f7da5634 ecx: c0308d1e edx: f738e974 esi: 00000000 edi: 00000000 ebp: f738e974 esp: f5539f18 ds: 0018 es: 0018 ss: 0018 Process mdadm (pid: 1731, stackpage=f5539000) Stack: c1c149c0 0ba4ee80 c0157b37 f63e1206 f7da5634 c1c149c0 c0308d1f 0ba4ee80 c0252f0b f738e974 c1c149ac 0ba4ee80 00000000 00000000 f738e974 c1c149ac 000001ec c015766d f738e974 c1c149ac f5539f74 f738e98c 00000000 00000007 Call Trace: [<c0157b37>] [<c0252f0b>] [<c015766d>] [<c013e2f3>] [<c0108bcb>] Code: 8b 87 d8 03 00 00 89 44 24 0c 8b 87 d4 03 00 00 89 2c 24 89 <6>md: md8 stopped. md: unbind<hde1,0> md: export_rdev(hde1) The whole thing passed through ksymoops: ksymoops 2.4.9 on i686 2.4.27. Options used -V (default) -k /proc/ksyms (default) -l /proc/modules (default) -o /lib/modules/2.4.27/ (default) -m /boot/System.map-2.4.27 (default) Warning: You did not tell me where to find symbol information. I will assume that the log matches the kernel and modules that are running right now and I'll use the default options above for symbol resolution. If the current kernel and/or modules do not match the log, you can get more accurate output by telling me the kernel version and where to find map, modules, ksyms etc. ksymoops -h explains the options. Unable to handle kernel NULL pointer dereference at virtual address 000003d8 c024be53 *pde = 00000000 Oops: 0000 CPU: 0 EIP: 0010:[<c024be53>] Not tainted Using defaults from ksymoops -t elf32-i386 -a i386 EFLAGS: 00010286 eax: c1c149ac ebx: f7da5634 ecx: c0308d1e edx: f738e974 esi: 00000000 edi: 00000000 ebp: f738e974 esp: f5539f18 ds: 0018 es: 0018 ss: 0018 Process mdadm (pid: 1731, stackpage=f5539000) Stack: c1c149c0 0ba4ee80 c0157b37 f63e1206 f7da5634 c1c149c0 c0308d1f 0ba4ee80 c0252f0b f738e974 c1c149ac 0ba4ee80 00000000 00000000 f738e974 c1c149ac 000001ec c015766d f738e974 c1c149ac f5539f74 f738e98c 00000000 00000007 Call Trace: [<c0157b37>] [<c0252f0b>] [<c015766d>] [<c013e2f3>] [<c0108bcb>] Code: 8b 87 d8 03 00 00 89 44 24 0c 8b 87 d4 03 00 00 89 2c 24 89 >>EIP; c024be53 <raid1_status+13/a0> <===== >>eax; c1c149ac <_end+1832a48/3a58b0fc> >>ebx; f7da5634 <_end+379c36d0/3a58b0fc> >>ecx; c0308d1e <cpdext+32e3e/3a8e0> >>edx; f738e974 <_end+36faca10/3a58b0fc> >>ebp; f738e974 <_end+36faca10/3a58b0fc> >>esp; f5539f18 <_end+35157fb4/3a58b0fc> Trace; c0157b37 <seq_printf+37/60> Trace; c0252f0b <md_seq_show+15b/2d0> Trace; c015766d <seq_read+1cd/2c0> Trace; c013e2f3 <sys_read+a3/140> Trace; c0108bcb <system_call+33/38> Code; c024be53 <raid1_status+13/a0> 00000000 <_EIP>: Code; c024be53 <raid1_status+13/a0> <===== 0: 8b 87 d8 03 00 00 mov 0x3d8(%edi),%eax <===== Code; c024be59 <raid1_status+19/a0> 6: 89 44 24 0c mov %eax,0xc(%esp) Code; c024be5d <raid1_status+1d/a0> a: 8b 87 d4 03 00 00 mov 0x3d4(%edi),%eax Code; c024be63 <raid1_status+23/a0> 10: 89 2c 24 mov %ebp,(%esp) Code; c024be66 <raid1_status+26/a0> 13: 89 00 mov %eax,(%eax) 1 warning issued. Results may not be reliable. regards, Mario -- Whenever you design a better fool-proof software, the genetic pool will always design a better fool. - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html