Kenneth Aafl?y wrote: > On Wednesday 09 March 2005 19:11, Anssi Hannula wrote: > > Johannes Stezenbach wrote: > > > We use 64 minor numbers per card. The new code in dvbdev.c should > > > allocate minor numbers > 255 for the 5th and 6th card, but it > > > maybe it doesn't. I don't have enough hardware to test, and > > > currently don't have the time to do a simulation. > > > > Isn't there only 256 minor numbers? > > Or did I understand something wrong? > > I did some snooping around on this, and the there is only 256 minor numbers > visible from userspace, the extra bits allocated in the kernel is for internal > use only: > > http://linux.bkbits.net:8080/linux-2.6/hist/include/linux/kdev_t.h?nav=index.html|src/.|src/include|src/include/linux http://lwn.net/Articles/49684/ suggests otherwise, but the mknod() binary seems to clip the minor number to 8 bits. The mknod() syscall however uses a fancy backwards compatible encoding which allows more than 8 bit minor numbers, see new_decode_dev() in the change of the bkbits page. I guess udev has a a similar bug then. > I have a solution to the problem though, but it requires that the minor > device numbers are reordered a bit, and everyone without udev/devfs will > need to recreate their device nodes. This is bad. We don't want this. Johannes
