Hello,
I am trying to install the srripc module - source at: http://www.cogent.ca/Software/SRR.html on a Linux 2.6.x kernel with udev support. The kernel generates an oops in misc_register, which is essentially the first call that the module makes on initialization. Oops output is attached below.
The module runs perfectly without udev support. Udev support is standard on Fedora Core and other distributions, and I want to run with the stock distribution kernel if possible. I have read the source for other misc drivers, tried 4 different kernels, two different distributions, scoured the web, and lurked in this mailing list. I cannot find my error, and frankly, I don't think the kernel should oops here - it should return an error if the input is mildly malformed.
I have tried running the module with no entry in /dev and with a manually created entry in /dev, with the same results. I attach code snippets relevant to the misc_register call below.
FWIW, I am running this within VMWare Workstation 4.5.2.
Any insight would be greatly appreciated.
Thanks, Andrew Thomas
-------- Code relevant to misc_register ---------
#define SRR_MINOR 171
static struct file_operations srr_fops = { .owner = THIS_MODULE, .poll = srr_poll, .ioctl = srr_ioctl, .open = srr_open, .flush = srr_flush, .release = srr_release };
static struct miscdevice SrrMiscDevice = { .minor = SRR_MINOR, .name = "srripc", .fops = &srr_fops, .devfs_name = "srripc" };
static int __init srr_module_init(void) { int result;
INIT_LIST_HEAD (&SrrMiscDevice.list);
SrrMiscDevice.minor = SRR_MINOR;
printk ("SRRIPC: Register misc device %d\n", srr_minor); result = misc_register (&SrrMiscDevice); printk ("SRRIPC: Register misc device complete\n"); ... }
module_init (srr_module_init);
-------------------- oops -----------------------
SRRIPC: Register misc device 171 Unable to handle kernel NULL pointer dereference at virtual address 00000021 printing eip: c025612d *pde = 00000000 Oops: 0000 [#1] Modules linked in: srripc parport_pc lp parport autofs4 sunrpc button battery ac md5 ipv6 uhci_hcd snd_ens1371 snd_rawmidi snd_seq_device snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd_page_alloc snd_ac97_codec snd soundcore gameport pcnet32 mii floppy dm_snapshot dm_zero dm_mirror ext3 jbd dm_mod BusLogic sd_mod scsi_mod CPU: 0 EIP: 0060:[<c025612d>] Not tainted VLI EFLAGS: 00010286 (2.6.9) EIP is at misc_register+0xd/0x1e0 eax: 00000021 ebx: c03c74c0 ecx: c03c4738 edx: c03c4738 esi: 00000021 edi: c03d5be0 ebp: c03c7480 esp: c6ee2f60 ds: 007b es: 007b ss: 0068 Process modprobe (pid: 4721, threadinfo=c6ee2000 task=ca839480) Stack: 0000001c 0000001e c03c74c0 d2a18380 c03c74c0 d2a18380 c03c7480 d2834034 d2a18280 d2a1520c 000000ab c03c74c0 c0147623 c8da23a0 fffffff7 00b7eba0 c6ee2000 c017ab61 c6ee2fac 00012bf5 b7fd1008 0805aab8 00000000 c6ee2000 Call Trace: [<d2834034>] srr_module_init+0x34/0x1e5 [srripc] [<c0147623>] sys_init_module+0x203/0x340 [<c017ab61>] sys_read+0x41/0x70 [<c010684d>] sysenter_past_esp+0x52/0x71 Code: 00 00 e8 77 91 ec ff eb b4 31 c0 89 47 10 e9 3b ff ff ff 8d 74 26 00 8d bc 27 00 00 00 00 57 bf e0 5b 3d c0 56 89 c6 53 83 ec 10 <8b> 00 c7 04 24 10 49 39 c0 89 44 24 04 e8 91 f8 ec ff ba 6b 00
-- Andrew Thomas, President, Cogent Real-Time Systems Inc. 162 Guelph Street, Suite 253, Georgetown, Ontario L7G 5X7, Canada Phone: 905-286-1081, Email: [EMAIL PROTECTED], Web: www.cogent.ca
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