Date: Fri, 9 Sep 2005 17:05:25 -0700 (PDT) From: Nate Eldredge <nge@cs.hmc.edu> To: FreeBSD-gnats-submit@FreeBSD.org Subject: kern/85931: panic: "vm_fault: fault on nofault entry" when using md Message-ID: <200509100005.j8A05PRh000906@vulcan.lan> Resent-Message-ID: <200509100010.j8A0AGhw067992@freefall.freebsd.org>
next in thread | raw e-mail | index | archive | help
>Number: 85931 >Category: kern >Synopsis: panic: "vm_fault: fault on nofault entry" when using md >Confidential: no >Severity: serious >Priority: medium >Responsible: freebsd-bugs >State: open >Quarter: >Keywords: >Date-Required: >Class: sw-bug >Submitter-Id: current-users >Arrival-Date: Sat Sep 10 00:10:15 GMT 2005 >Closed-Date: >Last-Modified: >Originator: Nate Eldredge >Release: FreeBSD 5.4-RELEASE-p6 amd64 >Organization: >Environment: System: FreeBSD vulcan.lan 5.4-RELEASE-p6 FreeBSD 5.4-RELEASE-p6 #0: Sun Sep 4 02:52:11 PDT 2005 nate@vulcan.lan:/usr/obj/usr/src/sys/VULCAN amd64 Opteron, 1 GB ram. >Description: I encountered a kernel panic when compiling the gcc40 port on a memory disk. As a benchmark test, I wanted to compile gcc on a ramdisk. "mdconfig -t malloc" cannot create such a large ramdisk, but I discovered after some research that you can use a preloaded ramdisk to accomplish this. So I created a 600MB sparse file in / (it had to be sparse because that partition is only 400MB large), rebooted and issued load -t md_image /sparse.img boot at the loader prompt. Then did along the lines of newfs /dev/md0 mount /dev/md0 /mnt/md0 mkdir /mnt/md0/nate # so as not to have to compile as root chown nate:nate /mnt/md0/nate su nate cd /mnt/md0/nate cp -r /usr/ports/lang/gcc40 . cd gcc40 time make After about 20 minutes the kernel panicked with the message vm_fault: fault on nofault entry, addr: ffffffffb36d8000 I have a vmcore file and can debug further if necessary. I can also test patches if I get them reasonably soon (this machine has to go into production eventually). On a previous attempt to do this, the machine rebooted after about 20 minutes but I did not get there in time to see if there was a panic message. So on the second attempt I watched and also enabled dumping. Thus it seems this may be reproducible. This is a new machine, so hardware problems are conceivable. But I had previously compiled gcc on disk several times as a burn-in test, without any problems. I also ran memtest86 overnight. The memory is ECC as well. >How-To-Repeat: See above. >Fix: I don't know. Thanks. >Release-Note: >Audit-Trail: >Unformatted:
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200509100005.j8A05PRh000906>