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* Is this normal or wrong?
@ 2013-03-07 14:45 ishare
  2013-03-12 13:23 ` Prabhu nath
  0 siblings, 1 reply; 3+ messages in thread
From: ishare @ 2013-03-07 14:45 UTC (permalink / raw)
  To: kernelnewbies


  In init procedure ,I use kmem_cache_alloc to apply for memory to locate a inode struct.
  it returns to me a inode whose i_dentry element cantain a struct list_head pointing to address 0x3,
  Is the address within low momery resonable or illegal?

  thanks!  

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Is this normal or wrong?
  2013-03-07 14:45 Is this normal or wrong? ishare
@ 2013-03-12 13:23 ` Prabhu nath
  2013-03-13  4:38   ` ishare
  0 siblings, 1 reply; 3+ messages in thread
From: Prabhu nath @ 2013-03-12 13:23 UTC (permalink / raw)
  To: kernelnewbies

kmem_cache_alloc() is used to allocate a memory object from a respective
cache.
Can you elaborate on what is ur objective or can you get us how you have
invoked this function.

To my understanding kmem_cache_alloc() will just return a linear virtual
address (void *) of a memory object.
It would not initialize this memory. What you are seeing is a stale value
which is unwarranted in this context.

-- 
Regards,
Prabhunath G
Linux Trainer
Bangalore


On Thu, Mar 7, 2013 at 8:15 PM, ishare <june.tune.sea@gmail.com> wrote:

>
>   In init procedure ,I use kmem_cache_alloc to apply for memory to locate
> a inode struct.
>   it returns to me a inode whose i_dentry element cantain a struct
> list_head pointing to address 0x3,
>   Is the address within low momery resonable or illegal?
>
>   thanks!
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>
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^ permalink raw reply	[flat|nested] 3+ messages in thread

* Is this normal or wrong?
  2013-03-12 13:23 ` Prabhu nath
@ 2013-03-13  4:38   ` ishare
  0 siblings, 0 replies; 3+ messages in thread
From: ishare @ 2013-03-13  4:38 UTC (permalink / raw)
  To: kernelnewbies

On Tue, Mar 12, 2013 at 06:53:49PM +0530, Prabhu nath wrote:
> kmem_cache_alloc() is used to allocate a memory object from a respective
> cache.
> Can you elaborate on what is ur objective or can you get us how you have
> invoked this function.
> 
> To my understanding kmem_cache_alloc() will just return a linear virtual
> address (void *) of a memory object.
>
  yes, it returns to me a struct inode * , whose valuse is reasonable ,  
  the value of its member  struct list_head i_dentry is {0x1,0x3 },their structures 
  is as below :
  
  struct inode 
 {
       struct hlist_node	i_hash;
       struct list_head		i_list;
       struct list_head		i_dentry;
       unsigned long		i_ino; 
 ....


 }

 struct list_head 
 {
     struct list_head *next, *prev;
 };

  After locate memory from cache , the i_dentry's **next** member,  whose valuse is 0x1 , will be used to
  linked with another list_head , in this procedure there is a addressing instruction to 0x1,but this time
  the low memory region has been zaped by setting pde at 0x0 to zero , so this addressing  causes a 
  page_fault, then goto reboot .

 how to resolve this ? 









 










> 
> -- 
> Regards,
> Prabhunath G
> Linux Trainer
> Bangalore
> 
> 
> On Thu, Mar 7, 2013 at 8:15 PM, ishare <june.tune.sea@gmail.com> wrote:
> 
> >
> >   In init procedure ,I use kmem_cache_alloc to apply for memory to locate
> > a inode struct.
> >   it returns to me a inode whose i_dentry element cantain a struct
> > list_head pointing to address 0x3,
> >   Is the address within low momery resonable or illegal?
> >
> >   thanks!
> >
> > _______________________________________________
> > Kernelnewbies mailing list
> > Kernelnewbies at kernelnewbies.org
> > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
> >

^ permalink raw reply	[flat|nested] 3+ messages in thread

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2013-03-07 14:45 Is this normal or wrong? ishare
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