>Number:         32116
>Category:       kern
>Synopsis:       kernel panic in uvm (assertion failure)
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Nov 19 12:38:01 +0000 2005
>Originator:     Christoph Egger
>Release:        NetBSD 3.99.11 (GENERIC) / Xen
>Organization:
>Environment:
>Description:

panic: kernel diagnostic assertion "LIST_FIRST(&pcbp->b_dep) != NULL" failed: file "/home/builds/ab/HEAD/src/sys/ufs/ffs/ffs_softdep.c", line 5995
Stopped in pid 12.1 (aiodoned) at netbsd:cpu_Debugger+0x4: leave cpu_Debugger(c078d000,9,0,0,0) at netbsd:cpu_Debugger+0x4
panic(c064d6e0,c05c3725,c06134,a0,c06122a0,176b) at netbsd:panic+0x121
__main(c05c3725,c06122a0,176b,c06134a0,c06d2d40) at netbsd:__main
softdep_pageiodone(c0a8e1cc,659fe,c088ce00,0,c5a4b948) at netbsd:softdep_pageiodone+0x294
uvm_aio_aiodone(c0a8e1cc,c03d9c09,c660ef8c,c03d9c31,0) at netbsd:uvm_aio_aiodone+0x461
uvm_aiodone_daemon(c5a4b948,783000,c078d000,0,c010017a) at netbsd:uvm_aiodone_daemon+0xb2
ds      0x11
es      0x11
fs      0x31
gs      0x11
edi     0x1
esi     0x100
ebp     0xc60ee2c
ebx     0x1
edx     0xc078d000  pci_bus_attached+0xb3ea0
ecx     0xffffffe0
eax     0x24b6
eip     0xc03deb08  cpu_Debugger+0x4
cs      0x9
eflags  0x1202
esp     0xc660ee2c
ss      0x11
netbsd:cpu_Debugger+0x4:   leave
Stopped in pid 12.1 (aiodoned) at     netbsd:cpu_Debugger+0x4:  leave


>How-To-Repeat:

Configuration:

Xen host: NetBSD-current (3.99.11, XEN0)
Xen guest: NetBSD-current (3.99.11, XENU)

both use FFSv2 with softdeps enabled

configure both as NFS client and server

xen host exports /usr/pkgsrc and /usr/pkgsrc-dist
xen guest exports /usr/pkgsrc-obj

xen host mounts /usr/pkgsrc-obj from xen guest in /usr/pkgsrc-obj
xen guest mounts /usr/pkgsrc and /usr/pkgsrc-dist from xen host in /usr/pkgsrc and /usr/pkgsrc-dist

Ensure that xen host and xen guest have read-write access to each other
via NFS

/etc/mk.conf is this:
DISTDIR=/usr/pkgsrc-dist
WRKOBJDIR=/usr/pkgsrc-obj
PKGVULNDIR=/usr/pkgsrc-obj


Steps to do:

cd /usr/pkgsrc/lang/perl5
make
<kernel panic happens during extracting the tarball>

>Fix: