On Fri, Jan 28, 2005 at 20:23:55 -0800, Om wrote: > On Fri, Jan 28, 2005 at 01:40:51PM -0800, Rock Gordon wrote: > > Hi everbody, > > > > Thanks for your replies. > > > > However I think my copy_to_user and copy_from_user are > > failing since the kernel-mode thread is copying data > > into another process's address space, and I am not > > sure how to do this. Do the get_fs() and set_fs() > > combinations let you do that? If not, then how do I do > My idea is on kernel thread is limited. But I think it is not possible to > any userspace address from any kernel thread because they do not have access > to it. Their proc_struct->mm field is empty. Right. You can't access any user-space from kernel thread, because it does not have any. > I am not sure whether set_fs and get_fs help in this case. Sure it can. set_fs(KERNEL_DS) sets things so, that if you pass kernel address to copy_to/from_user, it will silently accept it and copy to/from there. ------------------------------------------------------------------------------- Jan 'Bulb' Hudec <bulb@xxxxxx>
Attachment:
signature.asc
Description: Digital signature
