From mboxrd@z Thu Jan 1 00:00:00 1970 To: 9fans@cse.psu.edu Subject: Re: [9fans] fossil crash after installation From: "Russ Cox" Date: Mon, 4 Jun 2007 11:10:29 -0400 In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Message-Id: <20070604150702.3ABCD1E8C26@holo.morphisms.net> Topicbox-Message-UUID: 78220396-ead2-11e9-9d60-3106f5b1d025 > dma is left as bios left it. c.f. /sys/src/9/pc/sdata.c:/^atadmamode > so disabling dma in bios should do the trick. you can verify this > with > > ; /cat /dev/sdC0/ctl | grep config > config 427A capabilities 2F00 dma 00550040 dmactl 00000000 rwm 16 rwmctl 0 lba48always off > > the number following dmactl will be non-zero if dma is on. not true; dma is left off unless explicitly enabled with echo dma on >/dev/sdC0/ctl that has on occasion been put in termrc but i don't see it there now. dma does get enabled in the termrc used for installation, but i don't believe it stays enabled in the base system unless you modify your termrc yourself. what is true is that the specific dma mode used when dma is enabled is whatever got set up by the bios. but whether or not to use dma at all is a separate question and not one that plan 9 defers to the bios for. russ