Re: lock order reversal

On Tue, Nov 25, 2003 at 07:05:36PM -0600, John wrote:
> i was just looking through my daily reports from my new 5.2 beta box and 
> found this in dmesg.
> lock order reversal
>  1st 0xc08f7ce0 UMA lock (UMA lock) _at_ /usr/src/sys/vm/uma_core.c:1201
>  2nd 0xc1031100 system map (system map) _at_ /usr/src/sys/vm/vm_map.c:2210

Here is the stack trace for the first one:

lock order reversal
 1st 0xc098e840 UMA lock (UMA lock) _at_ /usr/src/sys/vm/uma_core.c:1201
 2nd 0xc1031100 system map (system map) _at_ /usr/src/sys/vm/vm_map.c:2210
Stack backtrace:
backtrace(c089c5dc,c1031100,c08afe80,c08afe80,c08afef6) at backtrace+0x17
witness_lock(c1031100,8,c08afef6,8a2,c10310a0) at witness_lock+0x672
_mtx_lock_flags(c1031100,0,c08afef6,8a2,c55ae000) at _mtx_lock_flags+0xba
_vm_map_lock(c10310a0,c08afef6,8a2,c5394bd0,0) at _vm_map_lock+0x36
vm_map_remove(c10310a0,c55ae000,c55af000,d77e5bf8,c07eacab) at vm_map_remove+0x30
kmem_free(c10310a0,c55ae000,1000,d77e5c28,c07ea6bf) at kmem_free+0x32
page_free(c55ae000,1000,2,0,c55ae000) at page_free+0x3b
zone_drain(c101e000,0,c08b16a1,4b1,0) at zone_drain+0x2cf
zone_foreach(c07ea3f0,d77e5cf0,c07e7b98,c08b154f,0) at zone_foreach+0x45
uma_reclaim(c08b154f,0,c08b14bc,29e,c095bf80) at uma_reclaim+0x17
vm_pageout_scan(0,0,c08b14bc,5a9,1f4) at vm_pageout_scan+0x148
vm_pageout(0,d77e5d48,c0896d18,311,0) at vm_pageout+0x31b
fork_exit(c07e8990,0,d77e5d48) at fork_exit+0xb4
fork_trampoline() at fork_trampoline+0x8
--- trap 0x1, eip = 0, esp = 0xd77e5d7c, ebp = 0 ---