From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 23 Jan 2001 08:01:24 +0100 (CET) From: Geert Uytterhoeven To: Robert E Brose II cc: linuxppc-dev@lists.linuxppc.org Subject: Re: [Dri-devel] PPC Lockup (ati-pcigart-branch) In-Reply-To: <20010123064948.1745.qmail@kunk.jriver.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Tue, 23 Jan 2001, Robert E Brose II wrote: > On Mon, 22 Jan 2001, Dan Malek wrote: > >> > ..... I > >> > wonder why planb works at all.... > >> > >> Probably because no one stumbles across the memory it is trashing? > >> Currently, bad_thing_will_happen = vmalloc + virt_to_bus + dma. > >> It could be with the right memory size, modulo addressing, memory > >> controller configuration, timing of the vmalloc, it just may > >> accidently work. If this is the case, I would be out buying > >> lottery tickets........ > > On Mon, 22 Jan 2001, Takashi Oe wrote: > > Ok, my apologies, planb doesn't use vmalloc at all these days. So, there > > is no problem of that kind. (In the beginning, it had vmalloc with a lot > > of problems as I recall now.) > > How about the use of vmalloc in the video frame buffer drivers? At > one point I ran into some weird behavior with controlfb (mmap patched), > XFree4.0, planb and Xawtv (the xawtv display froze the machine). I was > not able to duplicate that in X3.3.6 The frame buffer device drivers don't use vmalloc(), except for vfb, which is a sample driver that works on vmalloc()'ed memory instead of on real video memory. But you're right that vfb can crash if you try to mmap() its /dev/fb*, since it's vmalloc()'ed. However, that doesn't matter since no one will ever really use vfb :-) Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/