From: <ebi...@xm...> - 2003-10-27 15:16:03
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Linus Torvalds <tor...@os...> writes: > On Sat, 25 Oct 2003, Egbert Eich wrote: > > > > Speaking of XFree86: when I developed the PCI resource stuff in > > XFree86 I was trying to get support from kernel folks to get the > > appropriate user space interfaces into the kernel. When I got > > nowhere I decided to do everything myself. > > There won't be any "user space interfaces". There are perfectly good > in-kernel interfaces, and anybody who needs them needs to be in kernel > space. Ie the kernel interfaces are for kernel modules, not for user space > accesses. Well almost. There is still one significant flaw in the kernel space stuff. The BIOS can specify arbitrary regions as reserved in the E820 map and then a kernel driver can't use that region itself. This shows up in corner cases where the resource on the PCI device is a boolean rather than a general purpose thing. Particularly for mtd map drivers to allow flashing your ROM from linux this is a problem. This is not required for 2.6.0 but it would be nice to actually be able to reliably reserve resources in kernel drivers. Eric |