Chirag Kantharia wrote:
On Fri, Aug 20, 2004 at 11:05:05AM +0530, Nilanjan Roychowdhury wrote:
| > Can I access the user space data using copy_from_user from a
| > Kernel_thread ??
| No. Exactly whose user-space would the kernel thread access? | >>> if I do not call daemonize() then also I can't access any user space data ????
kernel threads don't run in context of a user process, and so, which user space data, do you wish to acces from kernel thread?
kernel threads don't have a user context. They cannot access any memory less than TASK_SIZE ( PAGE_OFFSET). Their mm field in the proc_struct is always null. They have only active_mm. This is implemented in daemonize() call.
HTH. Om.
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