kern/42551: Lockdebug assert in wapbl when running zpool

[ober%netbsd.org@localhost]

>Number:         42551
>Category:       kern
>Synopsis:       Lockdebug assert in wapbl when running zpool
>Confidential:   no
>Severity:       serious
>Priority:       low
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Dec 31 09:10:00 +0000 2009
>Originator:     NetBSD
>Release:        5.99.23 current as of 2009-12-30
>Organization:
NetBSD
>Environment:
NetBSD  5.99.23 NetBSD 5.99.23 (DEBUG) #0: Wed Dec 30 21:07:02 CST 2009  
root@:/usr/obj/sys/arch/amd64/compile/DEBUG amd64

>Description:
LOCKDEBUG/DIAGNOSTIC/DEBUG enabled GENERIC AMD64 from today
panics on command "zpool create pancake /dev/sd1a"
with
panic: kernel diagnostic assertion "rw_lock_held(&wl->wl_rwlock)" failed: file 
"/usr/src/sys/kern/vfs_wapbl.c", line 1542
breakpoint() at netbsd:breakpoint+0x5
panic() at netbsd:panic+0x29d
__kernassert() at netbsd:__kernassert+0x2d
wapbl_add_buf() at netbsd:wapbl_add_buf+0x36
bdwrite() at netbsd:bdwrite+0xc2
ffs_update() at netbsd:ffs_update+0x1ce
ffs_full_fsync() at netbsd:ffs_full_fsync+0x38b
ffs_fsync() at netbsd:ffs_fsync+0x4b
VOP_FSYNC() at netbsd:VOP_FSYNC+0x70
vinvalbuf() at netbsd:vinvalbuf+0xee
spec_close() at netbsd:spec_close+0x82
VOP_CLOSE() at netbsd:VOP_CLOSE+0x62
vn_close() at netbsd:vn_close+0x4b
closef() at netbsd:closef+0x6a
fd_close() at netbsd:fd_close+0x215
syscall() at netbsd:syscall+0xaa

db{2}> show registers
ds          0x3710
es          0x7
fs          0x8
gs          0x4dae
rdi         0
rsi         0xffffffff80684253  printf+0xbc
rbp         0xffff800071863740
rbx         0xffff800071863750
rdx         0x8
rcx         0
rax         0x1
r8          0xffffffff80aa5f69  copyright+0x9e589
r9          0
r10         0xffff800071863660
r11         0x1
r12         0x4
r13         0xffffffff80ab0760  copyright+0xa8d80
r14         0
r15         0x5
rip         0xffffffff80229a55  breakpoint+0x5
cs          0x8
rflags      0x246

fs          0x8
gs          0x4dae
rdi         0
rsi         0xffffffff80684253  printf+0xbc
rbp         0xffff800071863740
rbx         0xffff800071863750
rdx         0x8
rcx         0
rax         0x1
r8          0xffffffff80aa5f69  copyright+0x9e589
r9          0
r10         0xffff800071863660
r11         0x1
r12         0x4
r13         0xffffffff80ab0760  copyright+0xa8d80
rip         0xffffffff80229a55  breakpoint+0x5
cs          0x8
rflags      0x246

fs          0x8
gs          0x4dae
rdi         0
rsi         0xffffffff80684253  printf+0xbc
rbp         0xffff800071863740
rbx         0xffff800071863750
rdx         0x8
rcx         0
rax         0x1
r8          0xffffffff80aa5f69  copyright+0x9e589
r9          0
r10         0xffff800071863660
r11         0x1
r12         0x4
r13         0xffffffff80ab0760  copyright+0xa8d80
r14         0
r15         0x5
rip         0xffffffff80229a55  breakpoint+0x5
cs          0x8
rflags      0x246
rsp         0xffff800071863740
ss          0x10
netbsd:breakpoint+0x5:  leave

>How-To-Repeat:
Build GENERIC + DEBUG/LOCKDEBUG/DIAGNOSTIC
modload solaris
modload zfs
zpool create something /dev/sda1 
>Fix: