Re: [Xen-devel] RE: BUG() w/ HVM win2k3 64b

[Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>]

Oh, the bug is obvious actually. It's introduced by 16491, and is because
dst.type is getting clobbered to OP_NONE before it is tested for OP_REG.
I'll sort out a fix.

 Thanks!
 Keir

On 10/1/08 21:11, "Woller, Thomas" <thomas.woller@xxxxxxx> wrote:

>> 16489 and 16491 are obviously suspects. You might also try current tip
>> (-rc5) as some emulator bugs were fixed in the last day or
>> so. 
> 16491 just failed a few mins ago.  16490 passed at 9 hours, although
> could use more time.
> We are down to 3 1P test systems available for use till next week, and
> will start up:
> 1) 16701 minus 16491
> 2) 16701
> 3) 16701
> 
> And let them run overnight, which *should* be enough time.  If above all
> fail, we'll have to go back and work with 16489/16490 more closely with
> more time in test.
> 
>> Was your successful 16488 test stressful enough to be
>> confident that it's not a false negative (for the bug)?
> Yes, 2 systems confirmed 16488 passed.   Btw 3.1.3 passes also.
> 
> tom
> 
>> -----Original Message-----
>> From: Keir Fraser [mailto:Keir.Fraser@xxxxxxxxxxxx]
>> Sent: Thursday, January 10, 2008 2:56 PM
>> To: Woller, Thomas; xen-devel@xxxxxxxxxxxxxxxxxxx
>> Subject: Re: [Xen-devel] RE: BUG() w/ HVM win2k3 64b
>> 
>> 16489 and 16491 are obviously suspects. You might also try current tip
>> (-rc5) as some emulator bugs were fixed in the last day or
>> so. Was your successful 16488 test stressful enough to be
>> confident that it's not a false negative (for the bug)?
>> 
>>  -- Keir
>> 
>> On 10/1/08 19:36, "Woller, Thomas" <thomas.woller@xxxxxxx> wrote:
>> 
>>>> We have seen failures with changesets >= 16492, latest tested was
>>>> 16676 that fails, and c/s 16488 passes without issue.
>>> clarification to my email, was thinking that c/s 16491 was
>> the problem 
>>> (not 16492 as I indicated),
>>> 
>>> 16492 has failed tests, and 16491 c/s is running fine right
>> now - but 
>>> need more test time on that c/s to see if it will fail.
>>> 
>>> So, just to be clear, still don't have a handle on which
>> specific c/s 
>>> is the problem, but still seems around 1649x-ish
>>> 
>>> Tom
>>> 
>>> 
>>>> -----Original Message-----
>>>> From: Woller, Thomas
>>>> Sent: Thursday, January 10, 2008 1:18 PM
>>>> To: xen-devel@xxxxxxxxxxxxxxxxxxx
>>>> Cc: Woller, Thomas
>>>> Subject: BUG() w/ HVM win2k3 64b
>>>> 
>>>> We are observing a BUG() with 3.2/unstable.  This problem takes a
>>>> number of hours to reproduce - anywhere from 4 to 12+
>> hours, and only 
>>>> with windows 2003 64b HVM multi-vcpu guest so far under
>> heavy stress 
>>>> load.
>>>> 
>>>> Only reproduceable using Shadow Paging, we have not see
>> the problem 
>>>> using nested paging.
>>>> 
>>>> We have seen failures with changesets >= 16492, latest tested was
>>>> 16676 that fails, and c/s 16488 passes without issue.
>>>> 
>>>> We have tried to narrow down the issue to a specific
>> changeset, and 
>>>> overnight testing seems to indicate that changeset 14692
>> might be the 
>>>> culprit.  Not quite confirmed until additional testing completes
>>>> tomorrow on c/s 14691 and 14690.  We will know more EOD
>> thursday if 
>>>> these 2 pass testing.
>>>> 
>>>> We will startup some testing using 16701 also to make sure
>> that it is 
>>>> not resolved with post 16676 patches.  I'll also try to startup a
>>>> test with removing c/s 16492 from 16701 base and see if that helps
>>>> this specific problem.  All of this testing though will not finish
>>>> till towards end of next week due to largescale move of
>> lab/offices 
>>>> starting tomorrow - and with 3.2 almost out, would like to
>> see this 
>>>> figured out before release.
>>>> 
>>>> Reproduced on 1P family11h and family10h systems, but unable to
>>>> reproduce on 2P+ systems so far.  We don't believe we are
>>>> seeing any sort of h/w anomoly at this point.   have not
>>>> tried reproducing on VT boxes.
>>>> 
>>>> We are able to reproduce using 2 64b windows Guests,
>> currently we are
>>>> using 2 or 4 VCPUs, but have not tried reducing to single VCPU.
>>>> 
>>>> Any debug thoughts are appreciated.
>>>> 
>>>> Looks like the dst.mem.seg is invalid for the read() in
>> Grp5 case 2/4 
>>>> (jmp/call), which results in the BUG() later.
>>>> 
>>>> X86_emulate:
>>>> ...
>>>>     case 0xff: /* Grp5 */
>>>>         switch ( modrm_reg & 7 )
>>>>         {
>>>>         case 0: /* inc */
>>>>             emulate_1op("inc", dst, _regs.eflags);
>>>>             break;
>>>>         case 1: /* dec */
>>>>             emulate_1op("dec", dst, _regs.eflags);
>>>>             break;
>>>>         case 2: /* call (near) */
>>>>         case 4: /* jmp (near) */
>>>>             dst.type = OP_NONE;
>>>>             if ( (dst.bytes != 8) && mode_64bit() )
>>>>             {
>>>>                 dst.bytes = op_bytes = 8;
>>>>                 if ( dst.type == OP_REG )
>>>>                     dst.val = *dst.reg;
>>>>                 else if ( (rc = ops->read(dst.mem.seg, dst.mem.off,
>>>>                                           &dst.val, 8,
>> ctxt)) != 0 )
>>>>                     goto done;
>>>>          
>>>> 
>>>> Guest config:
>>>> HVM Windows 2003 64b
>>>> vcpus=4
>>>> memory=1024
>>>> pae/acpi/apic=1
>>>> 
>>>> BUG() info.
>>>> (XEN) Xen BUG at svm.c:599
>>>> (XEN) ----[ Xen-3.2.0-rc3  x86_64  debug=n  Tainted:    C ]----
>>>> (XEN) CPU:    2
>>>> (XEN) RIP:    e008:[<ffff828c80165205>]
>>>> svm_get_segment_register+0x145/0x170
>>>> (XEN) RFLAGS: 0000000000010292   CONTEXT: hypervisor
>>>> (XEN) rax: ffff8300a6e0ff28   rbx: ffff8300a7dde000   rcx:
>>>> 00000000a6e0fa28
>>>> (XEN) rdx: ffff830b14f09f54   rsi: 00000000a6e0fa28   rdi:
>>>> ffff8300a7ddc080
>>>> (XEN) rbp: ffff830b14f09f54   rsp: ffff8300a6e0f850   r8:
>>>> ffff8300a6e0fc98
>>>> (XEN) r9:  ffff8300a6e0f8c8   r10: 0000000000000000   r11:
>>>> 0000000000000001
>>>> (XEN) r12: ffff8300a6e0f8c8   r13: 0000000000000001   r14:
>>>> 00000000a6e0fa28
>>>> (XEN) r15: 0000000000000008   cr0: 0000000080050033   cr4:
>>>> 00000000000006f0
>>>> (XEN) cr3: 000000003b75b000   cr2: 000000000247f000
>>>> (XEN) ds: 0000   es: 0000   fs: 0053   gs: 002b   ss: 0000
>>   cs: e008
>>>> (XEN) Xen stack trace from rsp=ffff8300a6e0f850:
>>>> (XEN)    ffff830b14f09f54 0000000000000000 ffff828c80178eea
>>>> ffff8300a6e0fc98
>>>> (XEN)    ffff828c80179d0c ffff8300a6e0f8d0 ffff8300a6e0fb20
>>>> 0000000000000001
>>>> (XEN)    0000000000000008 ffff8300a6e0fc98 ffff8300a6e0fc98
>>>> 0000000000000004
>>>> (XEN)    ffff828c80179e46 0000000000000000 fffffadff3c54040
>>>> fffffadff04cbde0
>>>> (XEN)    0000000000000002 ffff828c801c18e0 0000000000000008
>>>> 0000000000000000
>>>> (XEN)    ffff828c80146be5 0000000000000001 ffff8300a6e0ff28
>>>> 000000003a4002e7
>>>> (XEN)    00000002a6e0fb87 ffff8300a6e0fbc8 0000001100000000
>>>> 0000000080a572b0
>>>> (XEN)    ffff8300a6e0f9d8 ffff828c801c18e0 0000000000000000
>>>> 0000000000000000
>>>> (XEN)    00000006a6e0fbc8 fffff80000812be8 0000468c8015a2b0
>>>> ffff8300a6e0fb03
>>>> (XEN)    0000000000000296 0000000000000002 ffff8300a7dd2080
>>>> 0000000000000000
>>>> (XEN)    ffff828c8013974a 0000000000000000 00000000ffffffff
>>>> ffff830000000046
>>>> (XEN)    ffff8300a7dd37e0 fffffadff04cbe00 fffffadff04cbd70
>>>> ffff8300a7dcd7e0
>>>> (XEN)    ffff828c80161206 fffff80000341070 fffffadff410d040
>>>> 0000000000000000
>>>> (XEN)    fffffadff41171f0 0000000000000080 fffffadff35ce040
>>>> fffff78000000008
>>>> (XEN)    0000000000000000 0000000000000000 fffffadff35ce040
>>>> fffffadff1a73010
>>>> (XEN)    fffffadff3699f90 fffffadff3699f90 fffffadff35ce040
>>>> fffffadff3c54040
>>>> (XEN)    0000000000000003 fffff80001272bae 0000000000000000
>>>> 0000000000000246
>>>> (XEN)    fffffadff04cbd70 0000000000000000 5555555555555555
>>>> 5555555555555555
>>>> (XEN)    5555555555555555 5555555555555555 00000001801324cd
>>>> 0000000000000004
>>>> (XEN)    ffffffffffffffff ffff8300a7ddc080 000fffff80001272
>>>> ffff8300a6e0fba4
>>>> (XEN) Xen call trace:
>>>> (XEN)    [<ffff828c80165205>] svm_get_segment_register+0x145/0x170
>>>> (XEN)    [<ffff828c80178eea>] hvm_get_seg_reg+0x3a/0x40
>>>> (XEN)    [<ffff828c80179d0c>] hvm_translate_linear_addr+0x3c/0xa0
>>>> (XEN)    [<ffff828c80179e46>] hvm_read+0x36/0xe0
>>>> (XEN)    [<ffff828c80146be5>] x86_emulate+0x3f35/0x9940
>>>> (XEN)    [<ffff828c8013974a>] smp_send_event_check_mask+0x3a/0x40
>>>> (XEN)    [<ffff828c80161206>] vlapic_write+0x546/0x7e0
>>>> (XEN)    [<ffff828c8017f3f5>]
>>>> sh_gva_to_gfn__shadow_4_guest_4+0xc5/0x150
>>>> (XEN)    [<ffff828c80152d27>] __hvm_copy+0x97/0x280
>>>> (XEN)    [<ffff828c8017f2ba>] guest_walk_tables+0x80a/0x880
>>>> (XEN)    [<ffff828c8017a206>] shadow_init_emulation+0x126/0x160
>>>> (XEN)    [<ffff828c80182bd5>]
>>>> sh_page_fault__shadow_4_guest_4+0xdb5/0xe80
>>>> (XEN)    [<ffff828c80128259>] context_switch+0xb79/0xbc0
>>>> (XEN)    [<ffff828c8016753c>] svm_vmexit_handler+0x6ac/0x1a70
>>>> (XEN)    [<ffff828c801160bf>] schedule+0x25f/0x290
>>>> (XEN)    [<ffff828c8015fcbd>] vlapic_has_pending_irq+0x2d/0x70
>>>> (XEN)    [<ffff828c80163dc6>] svm_intr_assist+0x46/0x140
>>>> (XEN)    [<ffff828c801692d4>] svm_stgi_label+0x8/0x14
>>>> (XEN)    
>>>> (XEN)
>>>> (XEN) ****************************************
>>>> (XEN) Panic on CPU 2:
>>>> (XEN) Xen BUG at svm.c:599
>>>> (XEN) ****************************************
>>>> (XEN)
>>>> (XEN) Manual reset required ('noreboot' specified)
>>>> 
>>>>   --Tom
>>>> 
>>>> thomas.woller@xxxxxxx  +1-512-602-0059 AMD Corporation - Operating
>>>> Systems Research Center
>>>> 5204 E. Ben White Blvd. UBC1
>>>> Austin, Texas 78741
>>>> 
>>>> 
>>> 
>>> 
>>> 
>>> _______________________________________________
>>> Xen-devel mailing list
>>> Xen-devel@xxxxxxxxxxxxxxxxxxx
>>> http://lists.xensource.com/xen-devel
>> 
>> 
>> 
>> 
>> 
> 
> 



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