port-arm32/50233: pmap_growkernel function crashed

[senfriend%gmail.com@localhost]

>Number:         50233
>Category:       port-arm32
>Synopsis:       pmap_growkernel function crashed
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    port-arm32-maintainer
>State:          open
>Class:          support
>Submitter-Id:   net
>Arrival-Date:   Fri Sep 11 18:00:00 +0000 2015
>Originator:     Senthil K
>Release:        NetBSD 5.1
>Organization:
Aricent
>Environment:
NetBSD 5.1
>Description:
We have observed the crash in uvm_map_prepare function.

 if (map == kernel_map && uvm_maxkaddr < (start + size))
        {
                    uvm_maxkaddr = pmap_growkernel(start + size;
 }
Added the trace inside the if statement. Its looks strange. 
uvm_maxkaddr = 0xffff ffff.
start = start=0xd5b00000, size=4096 

With the above value, the condition is false. but the its going inside if condition and crashed.


db> bt
0xd57da7e4: netbsd:vpanic+0xc
0xd57da7fc: netbsd:panic+0x28
0xd57da838: netbsd:lockdebug_abort+0x38
0xd57da8dc: netbsd:rw_vector_enter+0x20c
0xd57daa00: netbsd:uvm_fault_internal+0xd0
0xd57daa7c: netbsd:data_abort_handler+0x3d8
0xd57dab1c: netbsd:address_exception_entry+0x50
0xd57dab68: netbsd:uvm_map_prepare+0x284
0xd57dabcc: netbsd:uvm_map+0xc4
0xd57dac00: netbsd:km_vacache_alloc+0x60
0xd57dac30: netbsd:pool_grow+0x38
0xd57dac5c: netbsd:pool_get+0x12c

>How-To-Repeat:
N/A
>Fix: