Alpha problems entering DDB

[Kris Kennaway]

I finally caught the start of the infinite loop of error messages I am
getting on alpha machines.  As someone speculated, it is due to
entering DDB.  It doesn't seem to be 100% repeatable, as some of the
other machines have successfully entered DDB on a witness panic, but
it's happening often enough.

Kris

lock order reversal
 1st 0xfffffc001f4a0a80 vm object (vm object) @ /a/asami/portbuild/alpha/src-client/sys/vm/swap_pager.c:1323
 2nd 0xfffffc00006e4f48 swap_pager swhash (swap_pager swhash) @ /a/asami/portbuild/alpha/src-client/sys/vm/swap_pager.c:1838
 3rd 0xfffffc00236cb420 vm object (vm object) @ /a/asami/portbuild/alpha/src-client/sys/vm/uma_core.c:876
Stack backtrace:
db_print_backtrace() at db_print_backtrace+0x18
backtrace() at backtrace+0x2c
witness_lock() at witness_lock+0x6e8
_mtx_lock_flags() at _mtx_lock_flags+0xc8
obj_alloc() at obj_alloc+0x58
slab_zalloc() at slab_zalloc+0xcc
uma_zone_slab() at uma_zone_slab+0x108
uma_zalloc_internal() at uma_zalloc_internal+0x5c
uma_zalloc_arg() at uma_zalloc_arg+0x3f8
swp_pager_meta_build() at swp_pager_meta_build+0x168
swap_pager_putpages() at swap_pager_putpages+0x370
default_pager_putpages() at default_pager_putpages+0x1c
vm_pageout_flush() at vm_pageout_flush+0x1e0
_end() at 0xfffffc0023d246b0
prologue botch: displacement 48
frame size botch: adjust register offsets?
prologue botch: displacement 1520
frame size botch: adjust register offsets?
prologue botch: displacement 32
frame si
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-alpha/attachments/20031116/d53f8e3b/attachment.bin