Message-ID: <Pine.LNX.4.61.0712191503370.4688@chaos.analogic.com>
Date:	Wed, 19 Dec 2007 15:10:28 -0500
From:	"linux-os (Dick Johnson)" <linux-os@...logic.com>
To:	"Linux kernel" <linux-kernel@...r.kernel.org>
Subject: Trying to convert old modules to newer kernels



Here is a so-called BUG when trying to insert the following
module into the kernel (2.6.22.1).


BUG: unable to handle kernel paging request at virtual address 6814ec83
  printing eip:
c016d013
*pde = 00000000
Oops: 0000 [#1]
PREEMPT SMP 
Modules linked in: MemDev parport_pc lp parport nfsd exportfs lockd sunrpc iptable_filter ip_tables x_tables e1000 e100 mii nls_cp437 msdos fat dm_mod usbhid ff_memless uhci_hcd ehci_hcd video container button battery ac rtc ipv6 ext3 jbd ata_piix libata aic7xxx scsi_transport_spi sd_mod scsi_mod
CPU:    0
EIP:    0060:[<c016d013>]    Not tainted VLI
EFLAGS: 00010046   (2.6.22.1 #2)
EIP is at kmem_cache_alloc+0x23/0x80
eax: 00000000   ebx: 00000246   ecx: f8913300   edx: 6814ec83
esi: 00000000   edi: f8913000   ebp: ef27e000   esp: ef27ff74
ds: 007b   es: 007b   fs: 00d8  gs: 0033  ss: 0068
Process insmod (pid: 4593, ti=ef27e000 task=f614f550 task.ti=ef27e000)
Stack: f8913300 00000000 00000000 f8913013 f7fff880 000000d0 00000000 ef27e000
        c012b907 ffffffff 00000000 c0140279 bffedc07 bffedc08 0807a018 00000000
        c0102b82 0807a018 000018c9 0807a008 00000000 00000000 bffeabc8 00000080 
Call Trace:
  [<f8913013>] init_module+0x13/0x48 [MemDev]
  [<c012b907>] blocking_notifier_call_chain+0x17/0x20
  [<c0140279>] sys_init_module+0xd9/0x140
  [<c0102b82>] sysenter_past_esp+0x5f/0x85
  =======================
Code: 90 8d b4 26 00 00 00 00 83 ec 0c f6 c2 10 89 74 24 04 89 d6 89 7c 24 08 89 c7 89 1c 24 75 49 9c 5b fa 64 a1 04 20 47 c0 8b 14 87 <8b> 02 85 c0 74 25 c7 42 0c 01 00 00 00 48 89 02 8b 54 82 18 53 
EIP: [<c016d013>] kmem_cache_alloc+0x23/0x80 SS:ESP 0068:ef27ff74



Here is the code that causes the crash.


#include <linux/autoconf.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/mm.h>
static const char devname[]="Device";
#define NR_PAGES 0x10

struct DMA {
     void *ptr;
     unsigned long addr;
     size_t len;
     };
//-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//
//  The top-level object that gets allocated once, when the module is
//  installed.
//
struct INFO {
     struct file_operations fa;          // Kernel connection
     struct semaphore dev_sem;
     struct DMA dma[NR_PAGES];           // Can map one megabyte
     uint32_t vm_start;                  // Where mmap() starts
     uint32_t pages;                     // Number of pages mapped
     atomic_t open;                      // Number of opens
     };
//-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
static struct INFO *info;
//-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//
//   Initialize the module and return 0 if everything is okay.
//   Return a negative error-code if not.
//
static int32_t startup()
{
     if((info = kmalloc(sizeof(struct INFO), GFP_KERNEL)) == NULL) {
         printk(KERN_ALERT"%s : Can't allocate memory\n", devname);
         return -ENOMEM;
     }
     return 0;
}
//-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//
//  Cleanup the module in preparation for removal.
//
static void quit() {
     kfree(info);
     printk(KERN_INFO"%s : Module removed\n", devname);
}
MODULE_LICENSE("GPL");
MODULE_ALIAS("MemDev");
module_init(startup);
module_exit(quit);
//-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

Anybody have a clue why this should error out? Am I using
some reserved names??? I got rid of __init and anything
else that I thought could cause the fault, plus got rid
of all the code!



Cheers,
Dick Johnson
Penguin : Linux version 2.6.22.1 on an i686 machine (5588.29 BogoMips).
My book : http://www.AbominableFirebug.com/
_


****************************************************************
The information transmitted in this message is confidential and may be privileged.  Any review, retransmission, dissemination, or other use of this information by persons or entities other than the intended recipient is prohibited.  If you are not the intended recipient, please notify Analogic Corporation immediately - by replying to this message or by sending an email to DeliveryErrors@...logic.com - and destroy all copies of this information, including any attachments, without reading or disclosing them.

Thank you.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists