>Number:         25392
>Category:       kern
>Synopsis:       panic: amap_cow_now: non-resident wired page in anon
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Apr 29 17:17:00 UTC 2004
>Closed-Date:
>Last-Modified:
>Originator:     Martin J. Laubach
>Release:        NetBSD 1.6.2_STABLE
>Organization:
>Environment:
System: NetBSD asparagus.emsi.priv.at 1.6.2_STABLE NetBSD 1.6.2_STABLE (ASPARAGUS) #0: Wed Apr 28 20:55:29 CEST 2004 mjl@asparagus.emsi.priv.at:/storage/netbsd/cvs/src/sys16/arch/i386/compile/ASPARAGUS i386
Architecture: i386
Machine: i386
>Description:

  While preparing to burn a CD, after running mkisofs and the sequence of 
commands 

	vnconfig vnd0 m.iso
	mount -t cd9660 /dev/vnd0a /mnt
	ls /mnt
	umount /mnt
	vnconfig -u vnd0
	cdrecord -dev=/dev/rcd1c -v m.iso

  (cdrecord printed its usual blurb and started to count down before
burning the CD)

  the machine crashed. The last few lines in the kernel msgbuf are:

vnd0: no disk label
vnd0: no disk label
vnd0: no disk label
cd1(icpsp1:0:4:0):  Check Condition on CDB: 0x08 00 00 00 01 00
    SENSE KEY:  Illegal Request
     ASC/ASCQ:  Logical Block Address Out of Range

cd1: dos partition I/O error
panic: amap_cow_now: non-resident wired page in anon 0xd3826320
syncing disks... 1 done

dumping to dev 19,1 offset 299175

  Especially suspicious is the "dos partition I/O error" above,
since I never tried to do anything involving dos partitioning. Perhaps
some automagic try-to-guess-the-filesystem-type has gone haywire?

  The stack backtrace reads

(gdb) target kcore /scratch/crash/netbsd.0.core
panic: amap_cow_now: non-resident wired page in anon %p
#0  0x1 in ?? ()
(gdb) bt
#0  0x1 in ?? ()
#1  0xc01fb4f7 in cpu_reboot (howto=256, bootstr=0x0)
    at /home/users/mjl/netbsd/cvs/src/sys16/arch/i386/compile/ASPARAGUS/../../../../arch/i386/i386/machdep.c:2242
#2  0xc01a0a0f in panic ()
    at /home/users/mjl/netbsd/cvs/src/sys16/arch/i386/compile/ASPARAGUS/../../../../kern/subr_prf.c:253
#3  0xc01e625b in amap_cow_now (map=0xd3b1c81c, entry=0xd3b25618)
    at /home/users/mjl/netbsd/cvs/src/sys16/arch/i386/compile/ASPARAGUS/../../../../uvm/uvm_amap.c:792
#4  0xc01eeeb4 in uvmspace_fork (vm1=0xd3b1c8d8)
    at /home/users/mjl/netbsd/cvs/src/sys16/arch/i386/compile/ASPARAGUS/../../../../uvm/uvm_map.c:3132
#5  0xc01ea09f in uvm_fork (p1=0xd3b3501c, p2=0xd3b35cb0, shared=0, stack=0x0, 
    stacksize=0, func=0xc02017f0 <child_return>, arg=0xd3b35cb0)
    at /home/users/mjl/netbsd/cvs/src/sys16/arch/i386/compile/ASPARAGUS/../../../../uvm/uvm_glue.c:282
#6  0xc0191b1c in fork1 (p1=0xd3b3501c, flags=0, exitsig=20, stack=0x0, 
    stacksize=0, func=0, arg=0x0, retval=0xd3acaf78, rnewprocp=0x0)
    at /home/users/mjl/netbsd/cvs/src/sys16/arch/i386/compile/ASPARAGUS/../../../../kern/kern_fork.c:375
#7  0xc01916be in sys_fork (p=0xd3b3501c, v=0xd3acaf80, retval=0xd3acaf78)
    at /home/users/mjl/netbsd/cvs/src/sys16/arch/i386/compile/ASPARAGUS/../../../../kern/kern_fork.c:115
#8  0xc0201647 in syscall_plain (frame={tf_gs = 31, tf_fs = 31, tf_es = 31, 
      tf_ds = 31, tf_edi = 4096, tf_esi = 61440, tf_ebp = -1077955560, 
      tf_ebx = 0, tf_edx = 1387, tf_ecx = 1209242960, tf_eax = 2, 
      tf_trapno = 3, tf_err = 2, tf_eip = 1208856891, tf_cs = 23, 
      tf_eflags = 582, tf_esp = -1077955588, tf_ss = 31, tf_vm86_es = 0, 
      tf_vm86_ds = 0, tf_vm86_fs = 0, tf_vm86_gs = 0})
    at /home/users/mjl/netbsd/cvs/src/sys16/arch/i386/compile/ASPARAGUS/../../../../arch/i386/i386/syscall.c:140
#9  0xc0100c3c in syscall1 ()
can not access 0xbfbfb418, invalid translation (invalid PDE)
can not access 0xbfbfb418, invalid translation (invalid PDE)
Cannot access memory at address 0xbfbfb418


  A crash dump and kernel with symbols are available!

>How-To-Repeat:

>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted: