Re: Panic on dom0 shutdown

[Johan Ihrén <johani%johani.org@localhost>]

Hi guys,

Holidays intervened for a few days...

On Dec 20, 2012, at 20:41 , David Laight wrote:

> On Thu, Dec 20, 2012 at 07:39:18PM +0100, Manuel Bouyer wrote:
>> On Thu, Dec 20, 2012 at 06:42:14PM +0100, Johan Ihr?n wrote:
>>> I have a (reproducible) panic on shutdown, also recentish NetBSD 6 (kernel 
>>> form december 16), but no raidframe. In my case it only panics on "halt 
>>> -p", not on "halt" (100% reproducible). The trace is similar but not 
>>> identical (this is by hand, no serial console available):
>>> 
>>> kernel: page fault trap, code=0
>>> Stopped in pid 5800.1 (halt) at netbsd:bus_space_read_4*0x8:
>>> bus_space_read_4()
>>> Xresume_xenev6() at netbsd:Xresume_xenev6+0x47
>> 
>> there's something missing here, bus_space_read_4() is not called directly
>> by Xresume_xenev6().

Not questioning that, but the trace as I typed it looks like above.

>> Is it i386 or amd64 ? If amd64, please make sure
>> you still have -fno-omit-frame-pointer in kernel build options (makeoptions)

It's amd64, a standard XEN3_DOM0-kernel grabbed as a binary from a daily build 
at from www.fr.netbsd.org. I've built a local kernel also, ensuring that 
-fno-omit-frame-pointer is in the makeoptions. I've made one change and that is 
adding

usb* at ehci? flags 1

to get the USB keyboard working during boot.

> You might want to disable tail-calls if you want a full trace back.

I assume that may be the cause of the trace not being correct. Ok, so adding 
"-fno-optimize-sibling-calls" to makeoptions (is that the correct way of 
disabling tail-calls?) causes the trace to change like this:

kernel: page fault trap, code=0
Stopped in pid 634.1 (halt) at netbsd:bus_space_read_4*0x8:
bus_space_read_4()
pirq_interrupt()
Xresume_xenev6() at netbsd:Xresume_xenev6+0x47
--- interrupt ---
Xspllower() at netbsd:Xspllower+0xe
ahci_exec_command()
wd_standby()
wd_shutdown()
device_pmf_driver_shutdown()
pmf_system_shutdown()
cpu_reboot()
sys_reboot()
syscall()

Regards,

Johan