Subject: reproduceable softdep panic
To: None <>
From: Christos Zoulas <>
List: tech-kern
Date: 10/08/2005 22:51:15

I have a 10 line program that does open/write/lseek/write that reliably
panics the kernel but since it is a local DOS, I am not posting it here.
If you want a copy in order to debug the problem, please send me private mail.
Both NetBSD and FreeBSD have open PR's with this panic.


ffs_fsync: dirty: tag VT_UFS(1) type VREG(1), usecount 1, writecount 1, refcount 2, flags (080<VLOCKSWORK,ONWORKLIST>)
        tag VT_UFS, ino 477772, on dev 0, 7 flags 0xe, effnlink 1, nlink 1
        mode 0100775, owner 10080, group 10080, size 18628608 lock type vnlock:
EXCL (count 1) by pid 1374.1
panic: softdep_deallocate_dependencies: dangling deps
cpu_Debugger(c2204c44,1,cc697a2c,222b0,0) at netbsd:cpu_Debugger+0x4
panic(c04f8da0,0,c04c1565,0,0) at netbsd:panic+0x121
softdep_deallocate_dependencies(c2204c3c,c04c1565,37a,c2204c3c,74a4c) at netbsd:softdep_deallocate_dependencies+0x23
brelse(c2204c3c,74a4c,0,0,7ff) at netbsd:brelse+0x3b6
ffs_indirtrunc(cc933634,fffffff4,ffffffff,7991c0,0) at netbsd:ffs_indirtrunc+0x39f
ffs_truncate(cc697cf4,0,c04c4f60,11c2000,c04984a0) at netbsd:ffs_truncate+0xf87
VOP_TRUNCATE(cc936b1c,20,0,0,cc6036c4) at netbsd:VOP_TRUNCATE+0x40
ffs_write(cc697e24,4348736b,cc697e5c,202,c0497c60) at netbsd:ffs_write+0x5d1
VOP_WRITE(cc936b1c,cc697ec4,1,cc6036c4,cc936b1c) at netbsd:VOP_WRITE+0x34
vn_write(cc60c6a0,cc60c6c8,cc697ec4,cc6036c4,1) at netbsd:vn_write+0xbc
dofilewrite(cc80873c,4,cc60c6a0,806a020,8065000) at netbsd:dofilewrite+0x86
sys_write(cc80cd70,cc697f64,cc697f5c,c0537160,c02f806c) at netbsd:sys_write+0x75
syscall_plain() at netbsd:syscall_plain+0x1a5