On Mon, Feb 11, 2013 at 5:25 PM, anish singh <anish198519851985@xxxxxxxxx> wrote:
> Hi All,what will happen if the user space process gets scheduled out while
>
> To read/write data to user-space from kernel-space we use copy_from_user()
> and copy_to_user() functions.
>
> What is the use of these function?
> Why kernel can't directly access user address and read/write on to it?
you were using it?
copy_to/from_user should always be called from process context. So even if a process is scheduled out there is not impact, as when process schedule back in copying will resume to/from correct page.
> Can any one explain why kernel can't directly access the user-space address.
>
> Thanks
>
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