related to DRM panic on latest 7.1

[Aretm Kim]

Hello!

After the last update of the sources I have to panic if I try to start x-
server again.

The first time the server starts and runs well. However, if the x-server is 
ended and try to start x-server again the panic happens. 
 	
Radeon 9800 XT (R350)

uname-a
FreeBSD test-host 7.1-STABLE FreeBSD 7.1-STABLE # 0: Wed Mar 11 19:26:19 MSK 
2009 root @ test-host: / usr / obj / usr / src / sys / my amd64


Fatal trap 12: page fault while in kernel mode
fault virtual address   = 0x18                
fault code              = supervisor read data, page not present
instruction pointer     = 0x8:0xffffffff8020c3cb                
stack pointer           = 0x10:0xfffffffe80016b30               
frame pointer           = 0x10:0xffffff0001248000               
code segment            = base 0x0, limit 0xfffff, type 0x1b    
                        = DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags        = interrupt enabled, resume, IOPL = 0   
current process         = 11 (swi4: clock sio)                  
trap number             = 12                                    
panic: page fault                                               
Uptime: 2m36s                                                   
Physical memory: 2040 MB                                        
Dumping 191 MB: 176 160 144 128 112 96 80 64 48 32 16  

BT:

#0  doadump () at pcpu.h:195                                                                                                                                 
#1  0x0000000000000004 in ?? ()                                                                                                                              
#2  0xffffffff80353052 in boot (howto=260) at 
/usr/src/sys/kern/kern_shutdown.c:418                                                                          
#3  0xffffffff8035340c in panic (fmt=0xffffffff8054a763 "%s") at 
/usr/src/sys/kern/kern_shutdown.c:574                                                       
#4  0xffffffff804e5eda in trap_fatal (frame=0xfffffffe80016a80, eva=24) at 
/usr/src/sys/amd64/amd64/trap.c:764                                               
#5  0xffffffff804e62a5 in trap_pfault (frame=0xfffffffe80016a80, usermode=0) 
at /usr/src/sys/amd64/amd64/trap.c:680                                          
#6  0xffffffff804e6be7 in trap (frame=0xfffffffe80016a80) at 
/usr/src/sys/amd64/amd64/trap.c:449                                                             
#7  0xffffffff804ce36e in calltrap () at 
/usr/src/sys/amd64/amd64/exception.S:209                                                                            
#8  0xffffffff8020c3cb in radeon_get_vblank_counter (dev=0xffffff0001248000, 
crtc=0) at /usr/src/sys/dev/drm/radeon_irq.c:308                                
#9  0xffffffff80200540 in vblank_disable_fn (arg=Variable "arg" is not 
available.                                                                            
) at /usr/src/sys/dev/drm/drm_irq.c:91                                                                                                                       
#10 0xffffffff80365070 in softclock (dummy=Variable "dummy" is not available.                                                                                
) at /usr/src/sys/kern/kern_timeout.c:274                                                                                                                    
#11 0xffffffff80334273 in ithread_loop (arg=0xffffff000115d4a0) at 
/usr/src/sys/kern/kern_intr.c:1088                                                        
#12 0xffffffff803311de in fork_exit (callout=0xffffffff80334110 
<ithread_loop>, arg=0xffffff000115d4a0, frame=0xfffffffe80016c80)                            
    at /usr/src/sys/kern/kern_fork.c:810                                                                                                                     
#13 0xffffffff804ce73e in fork_trampoline () at 
/usr/src/sys/amd64/amd64/exception.S:455