From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jesse Barnes Date: Thu, 08 Jul 2004 18:39:53 +0000 Subject: Re: BUG 2.6.7 hangs on boot (rx2600) Message-Id: <200407081139.53679.jbarnes@engr.sgi.com> List-Id: References: <20040622061505.GA23075@cup.hp.com> In-Reply-To: <20040622061505.GA23075@cup.hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org On Thursday, July 8, 2004 11:31 am, Chen, Kenneth W wrote: > >>>> Jesse Barnes wrote on Thursday, July 08, 2004 11:13 AM > > > > > > Jesse, do you know if unapplying the "move current to region 5" patch > > > fixes your boot-problem? For convenience, I attached the (original) > > > patch below. > > > > Applying this small patch to head.S gets me as far as Grant's original > > report. > > > > -(isBP) br.cond.dpnt .load_current > > +//(isBP) br.cond.dpnt .load_current > > > > This lets me get to: > > > > PID hash table entries: 4096 (order 12: 65536 bytes) > > CPU 0: base freq 0.000MHz, ITC ratio/2, ITC freq00.000MHz+/--1ppm > > Console: colour dummy device 80x25 > > > > And like I've already mentioned, if I revert the whole thing the kernel > > boots fine. Ugg, I'm really starting to dislike the move of the > > init_task... > > It is something related to stack pointer (r12). If sp stays in region 7 > (providing there is a corresponding dtr mapping), kernel boots fine. David > mentioned that MCA code also has tpa thingy in it that needs to be > converted. One other thing I'm getting frustrated at is I'm keep on > receiving mca while doing a ptc.e (only on sgi altix). Have no idea why. I get different behavior depending on whether I'm on a partitioned system or not: either a machine check caused by a null pointer dereference in the unwind code on a non-partitioned machine, or a hang on a partitioned machine. The difference could be in leftover tc entries from the PROM. They'll get purged when the first ptc.e happens, causing a fault on the very next instruction or data reference following the purge. Just a guess. Jesse