From mboxrd@z Thu Jan 1 00:00:00 1970 Received: by oss.sgi.com id ; Fri, 29 Sep 2000 16:06:34 -0700 Received: from gateway-490.mvista.com ([63.192.220.206]:42748 "EHLO hermes.mvista.com") by oss.sgi.com with ESMTP id ; Fri, 29 Sep 2000 16:06:17 -0700 Received: from mvista.com (IDENT:jsun@orion.mvista.com [10.0.0.75]) by hermes.mvista.com (8.11.0/8.11.0) with ESMTP id e8TN57x15668; Fri, 29 Sep 2000 16:05:07 -0700 Message-ID: <39D5204A.8BE1E357@mvista.com> Date: Fri, 29 Sep 2000 16:05:46 -0700 From: Jun Sun X-Mailer: Mozilla 4.7 [en] (X11; I; Linux 2.2.12-20b i586) X-Accept-Language: en MIME-Version: 1.0 To: glonnon@ridgerun.com CC: linux-mips@oss.sgi.com, linux-mips@fnet.fr Subject: Re: problems execve("/sbin/init",...) References: <39D3FFE4.35E83599@ridgerun.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-linux-mips@oss.sgi.com Precedence: bulk Return-Path: X-Orcpt: rfc822;linux-mips-outgoing Greg Lonnon wrote: > > So, my questions are: > 1) Does anyone have a good way to debug in this small window going > between kernel mode and user mode for the first time? Not really. One time I had similar problem. I was able to figure out the problem by setting breakpoints in fault handlers. > 2) Is there anything else I could try to prove out that the kernel is > going into user mode? Try to set breakpoint in fault handlers. > 3) Has anyone else had these issues? > I found one bug in arch/mm/r4xx0.c, where cache invalidation causes recursive page faults. See the page below. Not sure if it is fixed in the tree yet. diff -Nru linux/arch/mips/mm/r4xx0.c.orig linux/arch/mips/mm/r4xx0.c --- linux/arch/mips/mm/r4xx0.c.orig Sun Jul 30 20:39:50 2000 +++ linux/arch/mips/mm/r4xx0.c Thu Aug 10 16:08:20 2000 @@ -1972,7 +1972,8 @@ if (!(vma->vm_flags & VM_EXEC)) return; - blast_icache32_page(address); + address = KSEG0 + (address & PAGE_MASK & (dcache_size - 1)); + blast_icache32_page_indexed(address); } /* Jun