kern/162362: ufs with snapshot(s) panics when getting full

[Michael Moll]

>Number:         162362
>Category:       kern
>Synopsis:       ufs with snapshot(s) panics when getting full
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Nov 07 23:00:19 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Michael Moll
>Release:        9.0-RC1
>Organization:
>Environment:
FreeBSD ufstest.kvedulv.de 9.0-RC1 FreeBSD 9.0-RC1 #0: Mon Nov  7 20:50:09 CET 2011     root at ufstest.kvedulv.de:/usr/obj/svn/base/stable/9/sys/UFSTEST  i386

>Description:
When an UFS (SUJ disabled) has a snapshot (or more) and gets filled up to the max, following panic(s) can be seen:

panic: softdep_deallocate_dependencies: unrecovered I/O error
cpuid = 0
KDB: stack backtrace:
db_trace_self_wrapper(c0e5bf2d,4,d33e6a20,0,536dd80a,...) at db_trace_self_wrapper+0x24
kdb_backtrace(0,d361cb5c,d339f698,d339f698,c44ec990,...) at kdb_backtrace+0x29
panic(c0e80675,d361cb98,c0a241f7,d339f698,0,...) at panic+0xfa
softdep_deallocate_dependencies(d339f698,0,d339f698,c17b4190,c44b7330,...) at softdep_deallocate_dependencies+0x36
brelse(d339f698,0,d339f698,d361cbd4,c0bceef5,...) at brelse+0x57
bufdone(d339f698,d339f698,c44bca6c,d361cbd4,c0cc68ae,...) at bufdone+0x4f
ufs_strategy(d361cbe4,d361cbe4,c0fa5240,c44ec990,d339f698,...) at ufs_strategy+0x55
bufstrategy(c44eca3c,d339f698,d339f6f8,0,0) at bufstrategy+0x28
bufwrite(d339f698,d339f698,8,4000,0,...) at bufwrite+0xc8
vfs_bio_awrite(d339f698,1000246,c40322e0,d339f6f8,0,...) at vfs_bio_awrite+0x59
flushbufqueues(0,c40322e0,c40322e0,2b6,d361ccf4,...) at flushbufqueues+0x5dc
buf_do_flush(0,c40322e0,c3d6e588,d361cd14,c0989df6,...) at buf_do_flush+0x1b
buf_daemon(0,d361cd28,0,0,c0a253e0,...) at buf_daemon+0xea
fork_exit(c0a253e0,0,d361cd28) at fork_exit+0x76
fork_trampoline() at fork_trampoline+0x8
--- trap 0, eip = 0, esp = 0xd361cd60, ebp = 0 ---
KDB: enter: panic
[ thread pid 7 tid 100034 ]
Stopped at      kdb_enter+0x34: movl    $0,kdb_why

----------------------------------

panic: softdep_deallocate_dependencies: unrecovered I/O error
cpuid = 0
KDB: stack backtrace:
db_trace_self_wrapper(c0e5bf2d,0,0,100000,1e8dac1d,...) at db_trace_self_wrapper+0x24
kdb_backtrace(0,d36a8768,d33856e4,d33856e4,0,...) at kdb_backtrace+0x29
panic(c0e80675,d36a87a4,c0a241f7,d33856e4,d36a8790,...) at panic+0xfa
softdep_deallocate_dependencies(d33856e4,d36a8790,d33856e4,c3d5c000,d33856e4,...) at softdep_deallocate_dependencies+0x36
brelse(d33856e4,d33856e4,c409a4ec,d33856e4) at brelse+0x57
bufwrite(d33856e4,16f88,0,c44fd500,0,...) at bufwrite+0x115
ffs_update(c496f880,1,60,0,c42d1b80,...) at ffs_update+0x20c
softdep_request_cleanup(c43e0800,c496f880,c42d2380,4) at softdep_request_cleanup+0x61
ffs_alloc(c496e5e4,8,0,2b580,0,4000,10000000,c42d2380,d36a8a5c,c496e5e4,8,0,8,c4970470) at ffs_alloc+0x1e4
ffs_balloc_ufs2(c496f880,20000,0,4000,c42d2380,10000000,d36a8af0) at ffs_balloc_ufs2+0x11de
ffs_write(d36a8bb4,0,c0bc2f30,c496f8d8,80400,...) at ffs_write+0x1c1
VOP_WRITE_APV(c0f94b40,d36a8bb4,0,100000,100001,...) at VOP_WRITE_APV+0x89
vn_write(c405c7a8,d36a8c48,c42d2380,0,c42d1b80) at vn_write+0x27f
dofilewrite(d36a8c48,ffffffff,ffffffff,0,c405c7a8,...) at dofilewrite+0x74
kern_writev(c42d1b80,4,d36a8c48) at kern_writev+0x49
sys_write(c42d1b80,d36a8cec,c42d1b80,202,0,...) at sys_write+0x41
syscall(d36a8d28) at syscall+0x48b

>How-To-Repeat:
Store some data on a UFS, snapshot it and then fill the FS until it's completely full.
>Fix:


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