Re: kern/46885: NetBSD 6.0_RC1 spontaneously reboots as kernel starts to load

[David Laight <david%l8s.co.uk@localhost>]

The following reply was made to PR kern/46885; it has been noted by GNATS.

From: David Laight <david%l8s.co.uk@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: kern-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
        netbsd-bugs%netbsd.org@localhost, 
dtyson%wirralcavinggroup.org.uk@localhost
Subject: Re: kern/46885: NetBSD 6.0_RC1 spontaneously reboots as kernel starts 
to load
Date: Sun, 2 Sep 2012 22:35:04 +0100

 On Sun, Sep 02, 2012 at 09:15:07PM +0000, Valeriy E. Ushakov wrote:
 >  
 >  I did a few more experiments under vbox --recompile-supervisor
 >  (i.e. ~= qemu interpreter) and it looks sensitive to size.
 >  
 >  Playing with the following config:
 >  
 >  
 >    include     "arch/i386/conf/GENERIC"
 >    options     PCIVERBOSE
 >  
 >    # this line has 64 bytes ######################################
 >    ###############################################################
 >    ###############################################################
 >    ...
 >  
 >  I do get bootable kernel without those comment lines added to beef up
 >  the kernel size.  With 12KB worth of comments I get unbootable kernel.
 >  With 16KB it's bootable again.  Current current will probably have
 >  different numbers, but you get the idea.
 
 Maybe nothing is flushing the dcache (or invalidating the icache)
 before the kernel starts?
 That would lead to obscure size based fubars.
 
 With vbox/qemu it might be possible to work out which!
 
 Another issue I have seen (a long time ago) was memory overwrites
 caused by rx ethernet frames when an ethernet chip didn't get reset.
 
        David
 
 -- 
 David Laight: david%l8s.co.uk@localhost