Re: [Qemu-devel] Ubuntu/Debian Installer + Virtio-SCSI -> Bad ram pointer

[Peter Lieven <pl@dlhnet.de>]

On 30.10.2012 09:32, Stefan Hajnoczi wrote:
> On Mon, Oct 29, 2012 at 03:09:37PM +0100, Peter Lieven wrote:
>> Hi,
> Bug subject should be virtio-blk, not virtio-scsi.  virtio-scsi is a
> different virtio device type from virtoi-blk and is not present in the
> backtrace you posted.
>
> Sounds pedantic but I want to make sure this gets chalked up against the
> right device :).
>
>> If I try to Install Ubuntu 12.04 LTS / 12.10 64-bit on a virtio
>> storage backend that supports iSCSI
>> qemu-kvm crashes reliably with the following error:
> Are you using vanilla qemu-kvm-1.2.0 or are there patches applied?
>
> Have you tried qemu-kvm.git/master?
>
> Have you tried a local raw disk image to check whether libiscsi is
> involved?
>
>> Bad ram pointer 0x3039303620008000
>>
>> This happens directly after the confirmation of the Timezone before
>> the Disk is partitioned.
>>
>> If I specify  -global virtio-blk-pci.scsi=off in the cmdline this
>> does not happen.
>>
>> Here is a stack trace:
>>
>> Thread 1 (Thread 0x7ffff7fee700 (LWP 8226)):
>> #0 0x00007ffff63c0a10 in abort () from /lib/x86_64-linux-gnu/libc.so.6
>> No symbol table info available.
>> #1 <https://github.com/sahlberg/libiscsi/issues/1>
>> 0x00005555557b751d in qemu_ram_addr_from_host_nofail (
>> ptr=0x3039303620008000) at /usr/src/qemu-kvm-1.2.0/exec.c:2835
>> ram_addr = 0
>> #2 <https://github.com/sahlberg/libiscsi/issues/2>
>> 0x00005555557b9177 in cpu_physical_memory_unmap (
>> buffer=0x3039303620008000, len=4986663671065686081, is_write=1,
>> access_len=1) at /usr/src/qemu-kvm-1.2.0/exec.c:3645
> buffer and len are ASCII junk.  It appears to be hex digits and it's not
> clear where they come from.
>
> It would be interesting to print *elem one stack frame up in #3
> virtqueue_fill() to show the iovecs and in/out counts.

(gdb) print *elem
$6 = {index = 3, out_num = 2, in_num = 4, in_addr = {1914920960, 1916656688,
     2024130072, 2024130088, 0 <repeats 508 times>, 4129, 93825009696000,
     140737328183160, 0 <repeats 509 times>}, out_addr = {2024130056,
     2038414056, 0, 8256, 4128, 93824999311936, 0, 3, 0 <repeats 512 times>,
     12385, 93825009696000, 140737328183160, 0 <repeats 501 times>}, 
in_sg = {{
       iov_base = 0x3039303620008000, iov_len = 4986663671065686081}, {
       iov_base = 0x3830384533334635, iov_len = 3544389261899019573}, {
       iov_base = 0x2aab32443039, iov_len = 16}, {iov_base = 0x2aab2365c628,
       iov_len = 1}, {iov_base = 0x0, iov_len = 0}, {iov_base = 0x0,
       iov_len = 0}, {iov_base = 0x2041, iov_len = 93825010788016}, {
       iov_base = 0x7ffff673f778, iov_len = 0}, {iov_base = 0x0,
       iov_len = 0} <repeats 256 times>, {iov_base = 0x1021,
       iov_len = 93825010788016}, {iov_base = 0x7ffff673f778, iov_len = 
0}, {
       iov_base = 0x0, iov_len = 0} <repeats 255 times>, {iov_base = 0x0,
       iov_len = 24768}, {iov_base = 0x1020, iov_len = 93824999311936}, {
       iov_base = 0x0, iov_len = 2}, {iov_base = 0x0,
       iov_len = 0} <repeats 256 times>, {iov_base = 0x1021,
       iov_len = 93825009696000}, {iov_base = 0x7ffff673f778, iov_len = 
0}, {
       iov_base = 0x0, iov_len = 0} <repeats 242 times>}, out_sg = {{
       iov_base = 0x2aab2365c608, iov_len = 16}, {iov_base = 0x2aab243fbae8,
       iov_len = 6}, {iov_base = 0x0, iov_len = 0} <repeats 11 times>, {
       iov_base = 0x0, iov_len = 33024}, {iov_base = 0x30,
       iov_len = 93825010821424}, {iov_base = 0x55555670d7a0, iov_len = 
0}, {
       iov_base = 0x55555670cbb0, iov_len = 0}, {iov_base = 0x71,
       iov_len = 93825008729792}, {iov_base = 0x55555670e960, iov_len = 
0}, {
       iov_base = 0x31, iov_len = 140737328183192}, {iov_base = 
0x7ffff673f798,
       iov_len = 0}, {iov_base = 0x555556711e20, iov_len = 80}, {
       iov_base = 0x20, iov_len = 93825010821584}, {iov_base = 0x0,
       iov_len = 33184}, {iov_base = 0x30, iov_len = 93825010821536}, {
       iov_base = 0x55555670e840, iov_len = 0}, {iov_base = 0x55555670e1b0,
       iov_len = 0}, {iov_base = 0x41, iov_len = 93825010821584}, {
       iov_base = 0x55555670eb20, iov_len = 32}, {iov_base = 0x20,
       iov_len = 93825010821920}, {iov_base = 0x0, iov_len = 33296}, {
       iov_base = 0x30, iov_len = 93825010821872}, {iov_base = 
0x55555670e8b0,
       iov_len = 0}, {iov_base = 0x55555670dc68, iov_len = 0}, {
       iov_base = 0x191, iov_len = 93825009696736}, {iov_base = 
0x55555670eb20,
       iov_len = 0}, {iov_base = 0x21, iov_len = 93825010826352}, {
       iov_base = 0x55555670e880, iov_len = 64}, {iov_base = 0x30,
       iov_len = 93825010821200}, {iov_base = 0x55555670e920, iov_len = 
0}, {
       iov_base = 0x55555670e5c8, iov_len = 0}, {iov_base = 0x41,
       iov_len = 93825008729792}, {iov_base = 0x55555670e9d0, iov_len = 
32}, {
       iov_base = 0x20, iov_len = 93825010821696}, {iov_base = 0x0,
       iov_len = 176}, {iov_base = 0x30, iov_len = 93825010821648}, {
       iov_base = 0x55555670e990, iov_len = 0}, {iov_base = 0x55555670e080,
       iov_len = 0}, {iov_base = 0x41, iov_len = 93825008729792}, {
       iov_base = 0x55555670eb20, iov_len = 32}, {iov_base = 0x20,
       iov_len = 93825010822032}, {iov_base = 0x0, iov_len = 288}, {
       iov_base = 0x30, iov_len = 93825010821984}, {iov_base = 
0x55555670ea00,
       iov_len = 0}, {iov_base = 0x55555670e000, iov_len = 0}, {
       iov_base = 0x41, iov_len = 93825010821808}, {iov_base = 
0x555556602590,
       iov_len = 32}, {iov_base = 0x20, iov_len = 93825009373648}, {
       iov_base = 0x0, iov_len = 33744}, {iov_base = 0x30,
       iov_len = 93825009373680}, {iov_base = 0x55555670ea70, iov_len = 
0}, {
       iov_base = 0x55555670da18, iov_len = 0}, {iov_base = 0x17271,
       iov_len = 93825009696736}, {iov_base = 0x7ffff673f778, iov_len = 
0}, {
       iov_base = 0x0, iov_len = 93825010821920}, {iov_base = 
0x55555670ec00,
       iov_len = 64}, {iov_base = 0x30, iov_len = 93825010822096}, {
       iov_base = 0x55555670eae0, iov_len = 0}, {iov_base = 0x55555670da48,
       iov_len = 0}, {iov_base = 0xb1, iov_len = 93825009696736}, {
       iov_base = 0x5555567066b0, iov_len = 0}, {iov_base = 0x21,
       iov_len = 93825010822032}, {iov_base = 0x55555670e8f0, iov_len = 
64}, {
       iov_base = 0x30, iov_len = 93825010821312}, {iov_base = 
0x55555670eb50,
       iov_len = 0}, {iov_base = 0x55555670df90, iov_len = 0}, {
       iov_base = 0x41, iov_len = 93825008729792}, {iov_base = 
0x55555670eab0,
       iov_len = 32}, {iov_base = 0x20, iov_len = 93825010821808}, {
       iov_base = 0x0, iov_len = 288}, {iov_base = 0x30,
       iov_len = 93825010821760}, {iov_base = 0x55555670ebc0, iov_len = 
0}, {
       iov_base = 0x55555670da40, iov_len = 0}, {iov_base = 0x17121,
       iov_len = 93825009372400}, {iov_base = 0x5555565fbfe0, iov_len = 
0}, {
       iov_base = 0x0, iov_len = 140737328184728}, {iov_base = 
0x5555565f9ea0,
       iov_len = 0}, {iov_base = 0x0, iov_len = 0} <repeats 255 times>, {
       iov_base = 0x0, iov_len = 4160}, {iov_base = 0x30,
       iov_len = 93825009721504}, {iov_base = 0x0, iov_len = 
93825010826368}, {
       iov_base = 0x3, iov_len = 3}, {iov_base = 0x160b1,
       iov_len = 93825009372400}, {iov_base = 0x7ffff673f778, iov_len = 
0}, {
       iov_base = 0x0, iov_len = 93825010826304}, {iov_base = 
0x55555670fc50,
       iov_len = 0}, {iov_base = 0x55555670edd0, iov_len = 0}, {
       iov_base = 0x16061, iov_len = 93825009372400}, {
       iov_base = 0x7ffff673f778, iov_len = 0}, {iov_base = 0x0,
       iov_len = 93825009688224}, {iov_base = 0x7ffff673fd98,
       iov_len = 93825010826464}, {iov_base = 0x55555670fce0, iov_len = 
0}, {
       iov_base = 0x0, iov_len = 0} <repeats 254 times>, {iov_base = 0x0,
       iov_len = 4160}, {iov_base = 0x30, iov_len = 93825010830976}, {
       iov_base = 0x55555670fcf0, iov_len = 0}, {iov_base = 0x55555670f060,
       iov_len = 0}, {iov_base = 0x71, iov_len = 93825008729792}, {
       iov_base = 0x555556710eb0, iov_len = 0}, {iov_base = 0x31,
       iov_len = 93825010821120}, {iov_base = 0x7ffff673f798,
       iov_len = 93825010821136}, {iov_base = 0x5555565fbbe8, iov_len = 
80}, {
       iov_base = 0x20, iov_len = 93825010831136}, {iov_base = 0x0,
       iov_len = 4320}, {iov_base = 0x30, iov_len = 93825010831088}, {
       iov_base = 0x555556710d90, iov_len = 0}, {iov_base = 0x555556710700,
       iov_len = 0}, {iov_base = 0x41, iov_len = 93825010831136}, {
       iov_base = 0x555556711070, iov_len = 32}, {iov_base = 0x20,
       iov_len = 93825010831472}, {iov_base = 0x0, iov_len = 4432}, {
       iov_base = 0x30, iov_len = 93825010831424}, {iov_base = 
0x555556710e00,
       iov_len = 0}, {iov_base = 0x5555567101b8, iov_len = 0}, {
       iov_base = 0x191, iov_len = 93825009372400}, {iov_base = 
0x555556711070,
       iov_len = 0}, {iov_base = 0x21, iov_len = 93825009374992}, {
       iov_base = 0x555556710dd0, iov_len = 64}, {iov_base = 0x30,
       iov_len = 93825010830752}, {iov_base = 0x555556710e70, iov_len = 
0}, {
       iov_base = 0x555556710b18, iov_len = 0}, {iov_base = 0x41,
       iov_len = 93825008729792}, {iov_base = 0x555556710f20, iov_len = 
32}, {
       iov_base = 0x20, iov_len = 93825010831248}, {iov_base = 0x0,
       iov_len = 176}, {iov_base = 0x30, iov_len = 93825010831200}, {
       iov_base = 0x555556710ee0, iov_len = 0}, {iov_base = 0x5555567105d0,
       iov_len = 0}, {iov_base = 0x41, iov_len = 93825008729792}, {
       iov_base = 0x555556711070, iov_len = 32}, {iov_base = 0x20,
       iov_len = 93825010831584}, {iov_base = 0x0, iov_len = 288}, {
       iov_base = 0x30, iov_len = 93825010831536}, {iov_base = 
0x555556710f50,
       iov_len = 0}, {iov_base = 0x555556710550, iov_len = 0}, {
       iov_base = 0x41, iov_len = 93825010831360}, {iov_base = 
0x55555670fc70,
       iov_len = 32}, {iov_base = 0x20, iov_len = 93825010826432}, {
       iov_base = 0x0, iov_len = 4880}, {iov_base = 0x30,
       iov_len = 93825010826384}, {iov_base = 0x555556710fc0, iov_len = 
0}, {
       iov_base = 0x55555670ff68, iov_len = 0}, {iov_base = 0x14d21,
       iov_len = 93825009372400}, {iov_base = 0x7ffff673f778, iov_len = 
0}, {
       iov_base = 0x0, iov_len = 93825010831472}, {iov_base = 
0x555556711150,
       iov_len = 64}, {iov_base = 0x30, iov_len = 93825010831648}, {
       iov_base = 0x555556711030, iov_len = 0}, {iov_base = 0x55555670ff98,
       iov_len = 0}, {iov_base = 0xb1, iov_len = 93825009372400}, {
       iov_base = 0x55555670fcc0, iov_len = 0}, {iov_base = 0x21,
       iov_len = 93825010831584}, {iov_base = 0x555556710e40, iov_len = 
64}, {
       iov_base = 0x30, iov_len = 93825010830864}, {iov_base = 
0x5555567110a0,
       iov_len = 0}, {iov_base = 0x5555567104e0, iov_len = 0}, {
       iov_base = 0x41, iov_len = 93825010831696}, {iov_base = 
0x555556711000,
       iov_len = 32}, {iov_base = 0x20, iov_len = 93825010831360}, {
       iov_base = 0x0, iov_len = 288}, {iov_base = 0x30,
       iov_len = 93825010831312}, {iov_base = 0x555556711110, iov_len = 
0}, {
       iov_base = 0x55555670ff90, iov_len = 0}, {iov_base = 0x14bd1,
       iov_len = 93825008729792}, {iov_base = 0x55555670fc70, iov_len = 
0}, {
       iov_base = 0x0, iov_len = 140737328185080}, {iov_base = 
0x7ffff673fef8,
       iov_len = 93825010831728}, {iov_base = 0x555556711170, iov_len = 
0}, {
       iov_base = 0x0, iov_len = 0} <repeats 255 times>...}}