Re: kern/46749: Accessing to ld0 at sdmmc0 causes kernel panic on NetBSD/i386 current

[David Holland <dholland-bugs%netbsd.org@localhost>]

The following reply was made to PR kern/46749; it has been noted by GNATS.

From: David Holland <dholland-bugs%netbsd.org@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: kern/46749: Accessing to ld0 at sdmmc0 causes kernel panic on
 NetBSD/i386 current
Date: Sat, 28 Jul 2012 17:33:08 +0000

 On Sat, Jul 28, 2012 at 05:25:00PM +0000, ryoon%NetBSD.org@localhost wrote:
  > When I access to /dev/ld0e on ld0 at sdmmc0, kernel panics.
  > SD card is formatted as ffs.
 
 oh wonderful...
 
 How repeatable is it?
 
  > % crash -M netbsd.4.core -N netbsd.4
  > Crash version 6.99.10, image version 6.99.10.
  > System panicked: pool_get(ffsdino2): free list modified: magic=0; page 
0xc280f000; item addr 0xc280fe00
 
  > Backtrace from time of crash is available.
  > [...]
  > 
sys_execve(c25582c0,daf45cf4,daf45d1c,c24b41b0,0,bb952c64,bb952000,c24b991c,0,3b)
 at sys_execve+0x30
 
 So it isn't (probably) the access to the thing that's the problem;
 mounting it corrupted the ffs dinode pool, and then it crashes the
 next time you go there.
 
 If it's repeatable, my inclination would be to sprinkle the mount code
 with integrity checks on that pool to figure out where it's getting
 trashed. But I don't know the pool interface for that offhand.
 
 -- 
 David A. Holland
 dholland%netbsd.org@localhost