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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt'><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> kernelnewbies-bounces@kernelnewbies.org [mailto:kernelnewbies-bounces@kernelnewbies.org] <b>On Behalf Of </b>Facundo Viale<br><b>Sent:</b> Friday, August 26, 2011 11:19 AM<br><b>To:</b> kernelnewbies@kernelnewbies.org<br><b>Subject:</b> I need suggestions for a practical work related with KernelDevelopment<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span class=apple-style-span><span style='font-size:10.0pt;font-family:"Arial","sans-serif";background:white'>Hi! I'm new here and i what to introduce myself i'm teacher in a University in the course Operation Systems. During the course the students learn some Operatyng Systems concepts, specially everything relating to the Kernel. As a practice task, they also have to use C to make a program with some Kernel functionalities. This year this task consists on programming a File System (I chose FAT32 since I thought it was the easiest one to implement) using FUSE and simulating a Hard Disk and a RAID behavior.<o:p></o:p></span></span></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";background:white'>Since I'm not a Kernel expert I'm looking for some advice and ideas. The aim of the practice task I'm creating is to help the students make a program that simulates the behavior and functionalities of a Kernel (such as a File System, Memory Administrator, Planner, etc.), but at the same I would like those programs to really interact with the Kernel, being not only ideal simulation cases (like FUSE). But, as I said, I don't know that much to have a good idea of what can I use to make the most from the Kernel in the task.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";background:white'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";background:white'>I could really use some ideas!<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";background:white'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";background:white'>Some of the things I have in mind:<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";background:white'><o:p> </o:p></span></p></div><div><div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#500050;background:white'>- Use netlinks<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#500050;background:white'>- Build a kernel module <o:p></o:p></span></p></div></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";background:white'>- I'm also interested in the /dev/mem<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";background:white'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";background:white'>ĄThanks a lot in advance! <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;background:white'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;background:white'>I would think if the goal is to teach them about kernel development, then having them write an actual kernel module would be more to the point than some user space application accessing a netlink socket or peeking and poking RAM with /dev/mem.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;background:white'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;background:white'>In a module you are running in kernel context so you have all the issues of memory management, different execution contexts (task context, IRQ context, soft IRQ context), synchronization to deal with that aren’t issues when running some user space simulator.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;background:white'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;background:white'>PCs are cheap these days. I assume each of your students would have access to his own so if his module panics the kernel of the machine he’s debugging his module on, it won’t affect the work of other students. If that’s not the case maybe my advice is not so applicable, though even if they have to share systems they could each run their own kernel in their own virtual machine and the hypervisor would keep them out of each other’s way. Actually, maybe that would be better since then they get a chance to learn a little about hypervisors too.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;background:white'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;background:white'>Jeff Haran<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;background:white'><o:p> </o:p></span></p></div></div></div></div><font face="monospace"></font></body></html>