On Wed, Jan 12, 2005 at 03:17:11PM +0100, Joakim Tjernlund wrote: > > On Wed, Jan 12, 2005 at 08:53:17AM +0100, Joakim Tjernlund wrote: > > > > As the code stands currently, there is a bug in the 2.4 and 2.6 handling > > > > of I-TLB Miss and Error exceptions on 8xx. The problem is that since we > > > > treat both of them as the same exception when we hit do_page_fault, > > > > there is a case where we can incorrectly find that a protection fault > > > > has occured, when it hasn't. This is because we check bit 4 of SRR1 in > > > > both cases, but in the case of an I-TLB Miss, this bit is always set, > > > > and it only indicates a protection fault on an I-TLB Error. > > > > > > Patch looks good to me, but I want to ask when this error > > > can be triggered in practice? > > > > It is possible to see this in the real world, as we (<hat=mvista>) found > > this with a customers app. > > hmm, this app must have been doing something pretty special. Any idea what > caused it?
Only vaugely. I'll poke the folks who did the investigation to see if they recall (the app is quite large) and follow up with details, I hope. -- Tom Rini http://gate.crashing.org/~trini/
