QuantumG's Blog

Recently, Greg K.H. made an offer to write free linux kernel drivers to any company that will provide him with docs to their hardware. Some BSD folks had a problem with Greg making this offer to people who would only give up their docs if the developer signed an NDA. Theo de Raadt chimed in declaring that "it is a fucking farce" , which is his usual way. As far as they are concerned, an open source driver without docs is not open at all. That may be so, but I still think having source code.. any source code.. which actually works, is better than having no docs or source code. It would be nice if companies would hand over docs without an NDA.. that is certainly preferable for everyone.. but some of them just won't, and getting them to hand over docs under an NDA with the ok for someone to write a free driver (be it GPL or BSD licensed) - that's something and it shouldn't be ignored. Now, if companies start doing this and drivers start showing up as GPL, but wi...

I'm a Ubuntu user but I also run a number of Windows machines for work purposes. I was actually shocked recently to discover that CUPS supports my Brother HL-5140 laser printer without me having to download any binary blobs from the Brother website. So that's good. What's not so great is that gnome-cups-ui has no concept of workgroups or domains for connecting via smb to a windows printer. When you go to "add new printer" or when you view the connection properties after adding the new printer, the fields you are presented with are: Host Printer Username Password After googling for a bit, I discovered that people have figured out that if you put the workgroup name in the Host field and then enter username:password@host/Printer into the Printer field and nothing into either the username or password fields, you can print! Curious about this obscurity, I did an apt-get source gnome-cups-ui and hunted around for a bit. Eventually, I found some code that looks basicall...

If you pop over to the NVIDIA web site and download the 3d card drivers for Linux, you'll note that there is a /usr/src/nv directory. In that directory is source code to the "thin layer" to the Linux kernel which NVIDIA links their binary blob. This, of course, makes no legal difference - NVIDIA are still extending the Linux kernel and therefore it is unlawful to distribute the Linux kernel along with the NVIDIA drivers, but NVIDIA doesn't do that, so it's not a problem - for them. Anyway, that's a side issue. I was thinking, recently, about the Linux kernel's "tainted" flag. Essentially, whenever you install a kernel module that isn't under some accepted open source license, the kernel sets a flag so that developers know there is a chance that any bugs you report might have been caused by code they can't fix. In general, this is not such a big deal as kernel modules are typically small and easy to isolate. The NVIDIA graphics driv...

Boomerang can now load Linux kernel modules and find the init_module and cleanup_module entrypoints. Loading ELF sections is a tricky business. I now honour the alignment information, which means kernel modules will load into Boomerang with the same section placement as they are loaded into IDA Pro. There was also some problems with the way we handle R_386_PC32 relocations. Checking the type of the symbol indicated by the relocation solves the problem. I also managed to speed it up significantly by removing an unnecessary check. Hopefully it really is unnecessary. My globals-at-decode-time code is now checked in. I await howls of disapproval on the mailing list, but hey, I do so every time I check in.