Date: Thu, 2 Jun 2005 09:40:31 -0700 From: Peter Wemm <peter@wemm.org> To: obrien@freebsd.org Cc: Michael Reifenberger <mike@Reifenberger.com>, freebsd-amd64@freebsd.org Subject: Re: 64bit loader Message-ID: <200506020940.32312.peter@wemm.org> In-Reply-To: <20050602082925.GB36096@dragon.NUXI.org> References: <20050531133608.J87922@fw.reifenberger.com> <200506011009.48460.peter@wemm.org> <20050602082925.GB36096@dragon.NUXI.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thursday 02 June 2005 01:29 am, David O'Brien wrote: > On Wed, Jun 01, 2005 at 10:09:47AM -0700, Peter Wemm wrote: > > Yes, there are a lot of good reasons to do it the way it is done, > > but this is the killer reason. We simply cannot do vm86 or bios > > calls from a 64 bit loader, period. > > > > Other "good" reasons, besides the above: > > * We don't need to maintain a seperate loader code base > > * We can load test kernels with an existing loader on a > > FreeBSD/i386 system (and run from a ramdisk or miniroot) > > * We would need to maintain 32 bit code to do bios calls anyway, > > even if we did switch between 32 bit and 64 bit mode on the fly. > > If we have a complete 32 bit BTX environment, we get massive > > complexity for little benefit. > > I personally am very happy with the way we handle switching into long > mode and loading 64-bit kernels today. :-) I think the current > advantages list > disadvantages list. BTW: I especially like sys/amd64/amd64/locore.s versus sys/i386/i386/locore.s -- Peter Wemm - peter@wemm.org; peter@FreeBSD.org; peter@yahoo-inc.com "All of this is for nothing if we don't go to the stars" - JMS/B5
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200506020940.32312.peter>