Re: panic in geom (spindown + eil + journal)

On Fri, 27 Jun 2008, Eygene Ryabinkin wrote:

Hi Eygene,

> Thu, Jun 26, 2008 at 08:19:46PM -0400, John Baldwin wrote:
>>> and when system will panic and debugger will be invoked, issue
>>> commands 'p *(bp->bio_offset)' and 'p *(cp->provider)' at the stack
>>> frame corresponding to the function g_io_request?
>>
>> Note that DDB can't handle structure dereferences like that (nor evaluate
>> symbols for local variables), you'll need to get a crash dump and use kgdb
>> for that sort of thing.
>
> Yes, you're right -- thanks for correcting me.  Bjoern, can you obtain
> the crash dump and see what is inside the passed structures?

Thanks for your replies but it seems you missed the initial messages?

Basically I am not asking how to get you two values out of a kernel
dump but what to check in the larger picture.

Nonetheless:
...
#26 0xffffffff802e8381 in panic (fmt=Variable "fmt" is not available.
) at /local/building/freebsd/HEAD.commit/sys/kern/kern_shutdown.c:572
#27 0xffffffff80297afb in g_io_request (bp=0xffffff0036a88948, cp=0xffffff0005c13900) at /local/building/freebsd/HEAD.commit/sys/geom/geom_io.c:356
#28 0xffffffff8029a524 in g_slice_start (bp=0xffffff004ba34948) at /local/building/freebsd/HEAD.commit/sys/geom/geom_slice.c:270
#29 0xffffffff802987c9 in g_io_schedule_down (tp=Variable "tp" is not available.
) at /local/building/freebsd/HEAD.commit/sys/geom/geom_io.c:540
#30 0xffffffff80298bf8 in g_down_procbody () at /local/building/freebsd/HEAD.commit/sys/geom/geom_kern.c:118
#31 0xffffffff802c797a in fork_exit (callout=0xffffffff80298b80 <g_down_procbody>, arg=0x0, frame=0xffffffff80c65c80) at /local/building/freebsd/HEAD.commit/sys/kern/kern_fork.c:818
#32 0xffffffff80569bbe in fork_trampoline () at /local/building/freebsd/HEAD.commit/sys/amd64/amd64/exception.S:521
...

(kgdb) p *(struct bio *)bp
$2 = {bio_cmd = 1 '\001', bio_flags = 0 '\0', bio_cflags = 0 '\0', bio_pflags = 0 '\0', bio_dev = 0x0, bio_disk = 0x0, bio_offset = 671299584, bio_bcount = 0,
   bio_data = 0xffffff005d004000 "..."..., bio_error = 0, bio_resid = 0, bio_done = 0, bio_driver1 = 0x0, bio_driver2 = 0x0, bio_caller1 = 0x0, bio_caller2 = 0x0,
   bio_queue = {tqe_next = 0x0, tqe_prev = 0xffffffff807dc960}, bio_attribute = 0x0, bio_from = 0xffffff0005c12780, bio_to = 0xffffff0005067200, bio_length = 2048,
   bio_completed = 0, bio_children = 1, bio_inbed = 0, bio_parent = 0x0, bio_t0 = {sec = 151220, frac = 9129407584079866780}, bio_task = 0, bio_task_arg = 0x0, bio_pblkno = 0}
(kgdb) frame 27
#27 0xffffffff80297afb in g_io_request (bp=0xffffff0036a88948, cp=0xffffff0005c13900) at /local/building/freebsd/HEAD.commit/sys/geom/geom_io.c:356
356                     KASSERT(bp->bio_offset % cp->provider->sectorsize == 0,
(kgdb) p *(struct bio *)bp
$3 = {bio_cmd = 1 '\001', bio_flags = 0 '\0', bio_cflags = 0 '\0', bio_pflags = 0 '\0', bio_dev = 0x0, bio_disk = 0x0, bio_offset = 671299584, bio_bcount = 0,
   bio_data = 0xffffff005d004000 "..."..., bio_error = 0, bio_resid = 0, bio_done = 0xffffffff8029c590 <g_std_done>, bio_driver1 = 0x0, bio_driver2 = 0x0,
   bio_caller1 = 0x0, bio_caller2 = 0x0, bio_queue = {tqe_next = 0x0, tqe_prev = 0x0}, bio_attribute = 0x0, bio_from = 0x0, bio_to = 0x0, bio_length = 2048, bio_completed = 0,
   bio_children = 0, bio_inbed = 0, bio_parent = 0xffffff004ba34948, bio_t0 = {sec = 0, frac = 0}, bio_task = 0, bio_task_arg = 0x0, bio_pblkno = 0}
(kgdb) p *(struct g_consumer *)cp
$4 = {geom = 0xffffff0051df1c00, consumer = {le_next = 0x0, le_prev = 0xffffff0051df1c20}, provider = 0xffffff0016265c00, consumers = {le_next = 0xffffff005d82e580,
     le_prev = 0xffffff0016265c20}, acr = 1, acw = 0, ace = 1, spoiled = 0, stat = 0xffffff0001ec5b40, nstart = 12, nend = 12, private = 0x0, index = 0}
(kgdb) p *(struct g_provider *)0xffffff0016265c00
$5 = {name = 0xffffff0016265c88 "acd0t01", provider = {le_next = 0xffffff0001ef8a00, le_prev = 0xffffff0001ef8b28}, geom = 0xffffff0001ef8b00, consumers = {
     lh_first = 0xffffff0005c13900}, acr = 1, acw = 0, ace = 1, error = 0, orphan = {tqe_next = 0x0, tqe_prev = 0x0}, mediasize = 0, sectorsize = 2352, stripesize = 0,
   stripeoffset = 0, stat = 0xffffff0001ec55a0, nstart = 35, nend = 35, flags = 0, private = 0x0, index = 1}


Again, during the time of panic there were no more CDs in either acd0 or acd1.
There had been some in a day before (no reboot in that timeframe).


Greetings
Bjoern

-- 
Bjoern A. Zeeb              Stop bit received. Insert coin for new game.