kern/147248: 8.0-RELEASE-p3 i386 Xen DomU filesystem "bufwait vfs_bio.c" and "dirhash ufs_dirhash.c" issue

[Yuriy Kohut]

>Number:         147248
>Category:       kern
>Synopsis:       8.0-RELEASE-p3 i386 Xen DomU filesystem "bufwait vfs_bio.c" and "dirhash ufs_dirhash.c" issue
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon May 31 15:40:19 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Yuriy Kohut
>Release:        8.0-RELEASE-p3
>Organization:
UK2
>Environment:
FreeBSD freebsd 8.0-RELEASE-p3 FreeBSD 8.0-RELEASE-p3 #1: Mon May 31 20:17:57 EEST 2010     root at fbsd.devel:/mnt/usr/src/sys/XEN  i386
>Description:
The following issue take place when ports collection is installing:

lock order reversal:
 1st 0xc67fa140 bufwait (bufwait) @ /usr/src/sys/kern/vfs_bio.c:2559
 2nd 0xc1763c00 dirhash (dirhash) @ /usr/src/sys/ufs/ufs/ufs_dirhash.c:285
KDB: stack backtrace:
X_db_sym_numargs(c0361263,cc7d8888,c0119f85,c010a59b,c036407c,...) at X_db_sym_numargs+0x146
kdb_backtrace(c010a59b,c036407c,c16c86d8,c16caf10,cc7d88e4,...) at kdb_backtrace+0x29
witness_display_spinlock(c036407c,c1763c00,c037dec7,c16caf10,c037db60,...) at witness_display_spinlock+0x75
witness_checkorder(c1763c00,9,c037db60,11d,0,...) at witness_checkorder+0x839
_sx_xlock(c1763c00,0,c037db60,11d,c1a2d2b8,...) at _sx_xlock+0x85
ufsdirhash_enduseful(c67fa0e0,c72f5800,200,c72f580c,cc7d89b4,...) at ufsdirhash_enduseful+0x2f5
ufsdirhash_add(c1a2d2b8,cc7d8a2c,80c,cc7d89a0,cc7d89a4,...) at ufsdirhash_add+0x13
ufs_direnter(c1a2153c,c1abc860,cc7d8a2c,cc7d8c10,c6867fa0,...) at ufs_direnter+0x729
ufs_readdir(cc7d8c38,cc7d8c4c,0,cc7d8be4,cc7d8b7c,...) at ufs_readdir+0x21d7
VOP_MKDIR_APV(c03bae00,cc7d8c38,68,0,0,...) at VOP_MKDIR_APV+0xa5
kern_mkdirat(c19a76c0,ffffff9c,28437780,0,1ed,...) at kern_mkdirat+0x211
kern_mkdir(c19a76c0,28437780,0,1ed,cc7d8d3c,...) at kern_mkdir+0x2e
mkdir(c19a76c0,cc7d8d08,8,c0364980,c039db60,...) at mkdir+0x29
syscall(cc7d8d48) at syscall+0x2a3
Xint0x80_syscall() at Xint0x80_syscall+0x22
--- syscall (136, FreeBSD ELF32, mkdir), eip = 0x28332723, esp = 0xbf7fc47c, ebp = 0xbf7fc4a8 ---
>How-To-Repeat:
1. Install FreeBSD paravirtualized DomU according to the HOWTO at:
http://forums.freebsd.org/showthread.php?t=10268


2. The only difference from the original HOWTO is guest disk based on real Linux LVM volume instead of file image.


3. Xen and Dom0 details
Linux xen0.vps 2.6.18-164.15.1.el5xen #1 SMP Wed Mar 17 12:04:23 EDT 2010 x86_64 x86_64 x86_64 GNU/Linux

CentOS release 5.4 (Final)

Xen version: 3.4.2


4. Log into FreeBSd DomU via ssh and run 'sysinstall' to install ports collection.


5. Check FreeBSD main console output
>Fix:
The issue seems to be not critical. The FreeBSD VPS is still actions as usual.

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