Re: Some alpha problems in current

[Anders Hjalmarsson <hjalmar%hjalmar.to@localhost>]

On Sat, 12 Jan 2008 17:03:34 GMT, Andrew Doran wrote:

> I made some changes to the pmap that could help the situation (rev 1.230 of
> arch/alpha/alpha/pmap.c). Can you try updating and see if the problem still
> persists? If it happens again, it would be really useful if you could get
> a backtrace from all the CPUs. For example:
> 
> mach cpu 0
> bt
> mach cpu 1
> bt 
> mach cpu 2
> bt
> ....
> 

Somewhat better, it stayed up for more than 10 minutes (multiuser, with
quite a few daemons started, some xterms, top, xosview etc).
Unfortunately I did not get a good backtrace on the other cpus,
but it looks like there is still some kind of pmap-related deadlock.

This is an ES40 with 4 cpus, in case that matters.

Here is what I managed to extract from ddb:

RMC>halt in

Returning to COM port

halted CPU 0
CPU 1 is not halted
CPU 2 is not halted
CPU 3 is not halted

halt code = 1
operator initiated halt
PC = fffffc0000622698
P00>>>c
continuing CPU 0
CP - RESTORE_TERM routine to be called
panic: user requested console halt
Stopped in pid 0.2 (system) at  netbsd:cpu_Debugger+0x4:        ret     
zero,(ra)
db{0}> bt
cpu_Debugger() at netbsd:cpu_Debugger+0x4
panic() at netbsd:panic+0x1c8
console_restart() at netbsd:console_restart+0x78
XentRestart() at netbsd:XentRestart+0x90
--- console restart (from ipl 5) ---
pmap_do_tlb_shootdown() at netbsd:pmap_do_tlb_shootdown+0x1f8
alpha_ipi_process() at netbsd:alpha_ipi_process+0xb8
interrupt() at netbsd:interrupt+0x80
XentInt() at netbsd:XentInt+0x1c
--- interrupt (from ipl 0) ---
sched_curcpu_runnable_p() at netbsd:sched_curcpu_runnable_p+0x10
idle_loop() at netbsd:idle_loop+0x18c
exception_return() at netbsd:exception_return
--- root of call graph ---

db{0}> mach cpu 1
Using CPU 1
db{0}> bt

CPU 0: fatal kernel trap:

CPU 0    trap entry = 0x2 (memory management fault)
CPU 0    a0         = 0xffffffffffffffd8
CPU 0    a1         = 0x1
CPU 0    a2         = 0x0
CPU 0    pc         = 0xfffffc000062ebfc
CPU 0    ra         = 0xfffffc000036c62c
CPU 0    pv         = 0xfffffc000062eb60
CPU 0    curlwp     = 0xfffffc003fc59cc0
CPU 0        pid = 0, comm = system

Caught exception in ddb.
db{0}> mach cpu 2
Using CPU 2
db{0}> bt
db{0}> mach cpu 3
Using CPU 3
db{0}> bt
db{0}>