Reproducable, possibly NFS related, fatal double fault in 6.2-R-p7

[Pyun YongHyeon]

On Mon, Oct 15, 2007 at 11:32:02PM +0300, Esa Karkkainen wrote:
 > On Sun, Oct 14, 2007 at 02:37:23PM +0200, Kris Kennaway wrote:
 > > Esa Karkkainen wrote:
 > > >	I get "Fatal double fault" error when writing to a filesystem
 > > >mounted from NFS server.
 > 
 > I got an offlist reply in which he suggested that the problem might be
 > in nve driver.
 > 
 > I installed an additional Intel nic, appropriate lines from dmesg are
 > as follows
 > 
 > fxp0: <Intel 82559 Pro/100 Ethernet> port 0xb000-0xb03f mem
 > 0xe7200000-0xe7200fff,0xe7000000-0xe70fffff irq 11 at device 6.0 on pci1
 > miibus1: <MII bus> on fxp0
 > inphy0: <i82555 10/100 media interface> on miibus1
 > inphy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
 > 
 > After I started to use fxp0, I can dump(8) all the necessary filesystems
 > to the NFS mount, with out panic.
 > 
 > When I used nve0 dump(8) or cp(1) managed to write less than megabyte to NFS
 > mount and then machine paniced.
 > 

I remember that nve(4) is NOT stable under heavy network loads.
I'd like to say use nfe(4) which is believed to be more stable/fast
than nve(4). nfe(4) is also default NVIDIA NIC driver for
CURRENT/RELENG_7. If you have to use RELENG_6 try nfe(4) at the
following URL.

http://www.f.csce.kyushu-u.ac.jp/~shigeaki/software/freebsd-nfe.html

 > It didn't matter if I made dump(8) write to the NFS mount or to a local
 > filesystem and then copied the file to NFS mount, the end result was a
 > panic.
 > 
 > > >	Both NFS server and client are running 6.2-RELEASE-p7.
 > 
 > Both machines have been updated to -p8.
 > 
 > > ># kgdb kernel.debug /home/crash/vmcore.2 
 > > >Fatal double fault:
 > > >eip = 0xc063242a
 > > 
 > > Can you look up these IPs in the kernel symbol table (see the developers 
 > > handbook)?  This might give at least one clue, although I'm not sure it 
 > > is relevant.
 > 
 > I'm sorry, but I need to learn alot more about gdb and debugging in
 > general before I can find that information. IIRC I have written about
 > ten or twenty lines of C in this millenia.
 > 
 > I do have matching kernel.debug and vmcore files, but kernel modules etc
 > have been removed before I made new kernel and world.
 > 
 > > You might also update to RELENG_6, I think there was at least one bug 
 > > fixed that might have caused such a thing.
 > 
 > At the moment I don't have any stability problems with this machine, but
 > I can upgrade to RELENG_6 before RELENG_6_3 is branched if that is
 > necessary.
 > 
 > > Also try to rule out memory failure etc.
 > 
 > This machine has two 512MB DDR333 DIMM's.
 > 
 > I installed sysutils/memtest and ran three simultaneously, first two
 > allocated 326 MB each and last one allocated 150 MB of memory, so I'd
 > start to swap. No errors.
 > 
 > I know these test are not conclusive, but I don't think DIMM's are 
 > faulty.
 > 
 > -- 

-- 
Regards,
Pyun YongHyeon