kern/114676: [ufs] snapshot creation panics: snapacct_ufs2: bad block

[Marcin Gryszkalis]

The following reply was made to PR kern/114676; it has been noted by GNATS.

From: Marcin Gryszkalis <mg at fork.pl>
To: freebsd-gnats-submit at freebsd.org,
 gael.roualland at dial.oleane.com
Cc:  
Subject: Re: kern/114676: [ufs] snapshot creation panics: snapacct_ufs2: bad block
Date: Sat, 9 Oct 2010 01:21:12 +0200

 I have this panic after crash caused by failed UPS.
 The system is 8.0-RELEASE-pX.
 The worse thing is that it caused endless loop of reboots (crash caused 
 background fsck+snapshot which caused panic which caused reboot+fsck etc.)
 
 UFS is placed over gmirror-ed disks (additionally checked with smartctl) so I 
 guess low level disk failure is not the cause.
 
 I have few dumps available.
 
 *blkp is BLK_SNAP 
 
 *ibp is
 $5 = {b_bufobj = 0xc585ea14, b_bcount = 16384, b_caller1 = 0x0, b_data = 
 0xdd1f3000 "\001", b_error = 0, b_iocmd = 2 '\002', b_ioflags = 2 '\002', 
 b_iooffset = 19662389248, 
   b_resid = 0, b_iodone = 0, b_blkno = 38403104, b_offset = -140257722368, 
 b_bobufs = {tqe_next = 0xd9226e90, tqe_prev = 0xd90e9a08}, b_left = 
 0xd92c08e0, 
   b_right = 0xd9281790, b_vflags = 0, b_freelist = {tqe_next = 0xd90e99d0, 
 tqe_prev = 0xd9226edc}, b_qindex = 2, b_flags = 2147483808, b_xflags = 1 '\001', 
 b_lock = {
     lock_object = {lo_name = 0xc0a74500 "bufwait", lo_flags = 91422720, lo_data 
 = 0, lo_witness = 0x0}, lk_lock = 3311290624, lk_timo = 0, lk_pri = 80}, 
 b_bufsize = 16384, 
   b_runningbufspace = 0, b_kvabase = 0xdd1f3000 "\001", b_kvasize = 16384, 
 b_lblkno = -8560652, b_vp = 0xc585e96c, b_dirtyoff = 0, b_dirtyend = 0, b_rcred 
 = 0x0, 
   b_wcred = 0x0, b_saveaddr = 0xdd1f3000, b_pager = {pg_reqpage = 0}, 
 b_cluster = {cluster_head = {tqh_first = 0x0, tqh_last = 0x0}, cluster_entry = 
 {tqe_next = 0x0, 
       tqe_prev = 0x0}}, b_pages = {0xc1a7e050, 0xc1a0a568, 0xc1a16ec8, 
 0xc16fdfe0, 0x0 <repeats 28 times>}, b_npages = 4, b_dep = {lh_first = 0x0}, 
 b_fsprivate1 = 0x0, 
   b_fsprivate2 = 0x0, b_fsprivate3 = 0x0, b_pin_count = 0}
 
 
 -- 
 Marcin Gryszkalis, PGP 0x9F183FA3 
 jabber jid:mg at fork.pl, gg:2532994
 http://the.fork.pl