Return to BSD News archive
Newsgroups: comp.os.386bsd.development Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!agate!howland.reston.ans.net!wupost!decwrl!netcomsv!netcom.com!hasty From: hasty@netcom.com (Amancio Hasty Jr) Subject: Re: 3C501 Ether driver, XS3+codrv Message-ID: <1993Mar12.190335.2343@netcom.com> Organization: Netcom Online Communications Services (408-241-9760 login: guest) References: <1993Mar11.090535.9238@gmd.de> <1993Mar12.033550.2947@netcom.com> <1993Mar12.074612.22684@gmd.de> Date: Fri, 12 Mar 1993 19:03:35 GMT Lines: 38 In article <1993Mar12.074612.22684@gmd.de> veit@fanoe.gmd.de (Holger Veit) writes: >In article <1993Mar12.033550.2947@netcom.com>, hasty@netcom.com (Amancio Hasty Jr) writes: >|> In article <1993Mar11.090535.9238@gmd.de> veit@fanoe.gmd.de (Holger Veit) writes: >|> >In article <1993Mar10.213242.423@netcom.com>, thinman@netcom.com (Technically Sweet) writes: >|> >kernel without problems. One is I/O and interrupt handling. There is >|> >a hack to give the xserver the privilege to access I/O but >|> >this imposes at least significant security leaks, if not stability >|> >problems. The way it is done in this context is not recommended in >|> >general. >|> Well, the original patches which I distributed for X386 included i/o >|> bitmap permissions. This approach was abandoned because of cards >|> based on the 8514/a, like s3 chipsets use i/o ports much higher >|> than normal vgas. We can still do it but it will be costly in >|> terms of memory allocation for the process header. > >This is because the 8514s have quite a wierd I/O space mapping. The constant >part is in the low byte, the high byte selects registers. I know this >has been done by intent to avoid address clashes, but as you correctly >remark, this enlarges the i386 task segment for each process by quite a >sparsely filled I/O perm map. > >Anything possible to improve this situation? Is it possible to >remap the I/O space 8514s to something more dense (besides a VGA emulation >mode)? The answer is no. So we are stuck with the current implementation for allowing i/o access to the 8514/a's i/o ports. Amancio -- This message brought to you by the letters X and S and the number 3 Amancio Hasty | Home: (415) 495-3046 | ftp-site depository of all my work: e-mail hasty@netcom.com | sunvis.rtpnc.epa.gov:/pub/386bsd/incoming