kern/46282: 6.0_BETA crash: msdosfs_bmap -> pcbmap -> bread -> bio_doread

[cheusov%tut.by@localhost]

>Number:         46282
>Category:       kern
>Synopsis:       6.0_BETA crash: msdosfs_bmap -> pcbmap -> bread -> bio_doread
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Mar 30 10:10:00 +0000 2012
>Originator:     Aleksey Cheusov
>Release:        NetBSD 6.0_BETA
>Organization:
>Environment:
System: NetBSD work.imb.invention.com 6.0_BETA NetBSD 6.0_BETA (GENERIC) #4: 
Mon Mar 26 15:56:02 FET 2012 
cheusov%work.imb.invention.com@localhost:/srv/obj-current/sys/arch/i386/compile/GENERIC
 i386
Architecture: i386
Machine: i386
>Description:
Stacktrace of the crash is below. It happened at the time
of writing to msdosfs filesystem.

#0  0xc05c5be8 in maybe_dump (howto=260) at 
/srv/src_netbsd6/sys/arch/i386/i386/machdep.c:878
#1  cpu_reboot (howto=260, bootstr=0x0) at 
/srv/src_netbsd6/sys/arch/i386/i386/machdep.c:899
#2  0xc07c320a in vpanic (fmt=0xc0c33178 "bio_doread: no such buf", 
ap=0xdb9187e8 "\240 ") at /srv/src_netbsd6/sys/kern/subr_prf.c:308
#3  0xc07c32af in panic (fmt=0xc0c33178 "bio_doread: no such buf") at 
/srv/src_netbsd6/sys/kern/subr_prf.c:205
#4  0xc08d354a in bio_doread (vp=0xca0d3b00, blkno=<optimized out>, size=65536, 
async=0, cred=<optimized out>) at /srv/src_netbsd6/sys/kern/vfs_bio.c:667
#5  0xc08d366c in bread (vp=0xca0d3b00, blkno=8352, size=65536, 
cred=0xffffffff, flags=0, bpp=0xdb918890) at 
/srv/src_netbsd6/sys/kern/vfs_bio.c:722
#6  0xc05fab22 in pcbmap (dep=0xc56591f0, findcn=15, bnp=0xdb9188fc, cnp=0x0, 
sp=0x0) at /srv/src_netbsd6/sys/fs/msdosfs/msdosfs_fat.c:257
#7  0xc05ff02b in msdosfs_bmap (v=0xdb918948) at 
/srv/src_netbsd6/sys/fs/msdosfs/msdosfs_vnops.c:1662
#8  0xc0907862 in VOP_BMAP (vp=0xc75a5794, bn=14, vpp=0xdb9189ec, 
bnp=0xdb9189dc, runp=0xdb9189f0) at /srv/src_netbsd6/sys/kern/vnode_if.c:1166
#9  0xc0341a72 in genfs_do_io (vp=0xc75a5794, off=<optimized out>, 
kva=3655794688, len=16384, flags=9, rw=UIO_WRITE, iodone=0xc08c7b4d 
<uvm_aio_biodone>) at /srv/src_netbsd6/sys/miscfs/genfs/genfs_io.c:1396
#10 0xc034489c in genfs_gop_write (vp=0xc75a5794, pgs=0xdb918b7c, npages=4, 
flags=9) at /srv/src_netbsd6/sys/miscfs/genfs/genfs_io.c:1288
#11 0xc0343fa7 in genfs_do_putpages (vp=0xc75a5794, startoff=458752, 
endoff=462848, origflags=9, busypg=0x0) at 
/srv/src_netbsd6/sys/miscfs/genfs/genfs_io.c:1172
#12 0xc034483b in genfs_putpages (v=0xdb918c38) at 
/srv/src_netbsd6/sys/miscfs/genfs/genfs_io.c:806
#13 0xc0907c36 in VOP_PUTPAGES (vp=0xc75a5794, offlo=458752, offhi=462848, 
flags=9) at /srv/src_netbsd6/sys/kern/vnode_if.c:1428
#14 0xc08c8a76 in uvmpd_scan_queue () at 
/srv/src_netbsd6/sys/uvm/uvm_pdaemon.c:784
#15 uvmpd_scan () at /srv/src_netbsd6/sys/uvm/uvm_pdaemon.c:946
#16 uvm_pageout (arg=0xc3826800) at /srv/src_netbsd6/sys/uvm/uvm_pdaemon.c:303
#17 0xc0100321 in ?? ()
>How-To-Repeat:
>Fix:
no idea