Hi all,
I have two questions connected to memory access from kernel ...

1) is it correct to access memory allocated in user space within my
driver? I've created an ioctl which gets a buffer from application and
which should be filled by driver .. Is it correct or there is any
restriction?

2) when accessing memory mapped for DMA access, I sometimes get an
"uvm_fault: page fault error". It seems that pointer is valid (points
into allocated buffer), what can be an other reason for it? Page fault
seems strange to me in such situation ...

Thanks all
Michal Filka