Re: [Qemu-devel] [Question] QEMU 2.3 Assertion with `existing->mr->subpage || existing->mr == &io_mem_unassigned' failed

[Gonglei]

On 2015/9/14 17:28, Paolo Bonzini wrote:
> 
> 
> On 14/09/2015 10:01, Gonglei (Arei) wrote:
>> [2015-09-11 13:42:44] domain is rebooting 
>> qemu-kvm: /home/abuild/rpmbuild/BUILD/qemu-kvm-2.3.0/exec.c:1188: 
>> register_subpage: Assertion `existing->mr->subpage || existing->mr == 
>> &io_mem_unassigned' failed. 
>> [2015-09-11 13:42:58]: shutting down
>>
>> Or
>> qemu-kvm: 
>> /home/abuild/rpmbuild/BUILD/qemu-kvm-2.3.0/include/qemu/int128.h:22: 
>> int128_get64: Assertion `!a.hi' failed.
> 
> You need to provide a backtrace.
> 
> Paolo
> 
Yup, I noticed that, but when I sent this email yesterday, I didn't get a 
backtrace :(
Fortunately,   I get a backtrace now:

#0 int128_get64 (a=...) at /home/qemu/include/qemu/int128.h:27
#1 0x00007f17ad7a7f1a in register_multipage (d=0x7f179c4f8480, 
section=0x7f17a323c3f0) at /home/qemu/exec.c:1215
#2 0x00007f17ad7a8266 in mem_add (listener=0x7f17ae043968 
<address_space_io+72>, section=0x7f17a323c730) at /home/qemu/exec.c:1250
#3 0x00007f17ad7f843a in address_space_update_topology_pass (as=0x7f17ae043920 
<address_space_io>, old_view=0x7f179c1f8b50, new_view=0x7f179c523620, 
adding=true)
at /home/qemu/memory.c:739
#4 0x00007f17ad7f8520 in address_space_update_topology (as=0x7f17ae043920 
<address_space_io>) at /home/qemu/memory.c:754
#5 0x00007f17ad7f8660 in memory_region_transaction_commit () at 
/home/qemu/memory.c:794
#6 0x00007f17ad9a690c in cirrus_update_memory_access (s=0x7f17b12873c0) at 
hw/display/cirrus_vga.c:2485
#7 0x00007f17ad9a4dac in cirrus_vga_write_gr (s=0x7f17b12873c0, reg_index=9, 
reg_value=163) at hw/display/cirrus_vga.c:1524
#8 0x00007f17ad9a6e47 in cirrus_vga_ioport_write (opaque=0x7f17b12873c0, 
addr=975, val=163, size=1) at hw/display/cirrus_vga.c:2672
#9 0x00007f17ad7f6882 in memory_region_write_accessor (mr=0x7f17b1297d88, 
addr=31, value=0x7f17a323c968, size=1, shift=8, mask=255) at 
/home/qemu/memory.c:430
#10 0x00007f17ad7f698b in access_with_adjusted_size (addr=30, 
value=0x7f17a323c968, size=2, access_size_min=1, access_size_max=1, 
access=0x7f17ad7f67fd <memory_region_write_accessor>, mr=0x7f17b1297d88)
at /home/qemu/memory.c:467
#11 0x00007f17ad7f9311 in memory_region_dispatch_write (mr=0x7f17b1297d88, 
addr=30, data=41737, size=2) at /home/qemu/memory.c:1103
#12 0x00007f17ad7fc22e in io_mem_write (mr=0x7f17b1297d88, addr=30, val=41737, 
size=2) at /home/qemu/memory.c:2003
#13 0x00007f17ad7aafe4 in address_space_rw (as=0x7f17ae043920 
<address_space_io>, addr=974, buf=0x7f17ad6f6000 "\t\243\320", len=2, 
is_write=true) at /home/qemu/exec.c:2533
#14 0x00007f17ad7f3acf in kvm_handle_io (port=974, data=0x7f17ad6f6000, 
direction=1, size=2, count=1) at /home/qemu/kvm-all.c:1707
#15 0x00007f17ad7f3fb5 in kvm_cpu_exec (cpu=0x7f17b05b7a20) at 
/home/qemu/kvm-all.c:1864
#16 0x00007f17ad7db416 in qemu_kvm_cpu_thread_fn (arg=0x7f17b05b7a20) at 
/home/qemu/cpus.c:972
#17 0x00007f17ac2cbdf5 in start_thread () from /lib64/libpthread.so.0
#18 0x00007f17a73e31ad in clone () from /lib64/libc.so.6

It seems that something wrong happened in vga memory updating.

Regards,
-Gonglei