Re: [Qemu-devel] DOS VM problem with QEMU-KVM and newer kernels

[Gerhard Wiesinger]

On Mon, 16 Apr 2012, Avi Kivity wrote:

> On 04/16/2012 01:30 PM, Roedel, Joerg wrote:
> > On Mon, Apr 16, 2012 at 12:25:37PM +0200, Jan Kiszka wrote:
> > > On 2012-04-15 11:44, Avi Kivity wrote:
> > > > Jan, Joerg, was an AMD erratum published for the bug?
> > >
> > > It wasn't an erratum but a documented feature limitation in the AMD
> > > architecture that was simply ignored by the old code.
> >
> > Right. But there is an erratum on K8 (only) which Kevin ran into. It is
> > documented as Erratum 701 and the bug is that no EXITINTINFO is stored
> > on a task-switch intercept on K8.
>
> Ah, so this could affect Gerhard.  Gerhard, what's your cpu
> family/model/stepping from /proc/cpuinfo?

Only CPU 0 of 3:
processor       : 0
vendor_id       : AuthenticAMD
cpu family      : 16
model           : 4
model name      : AMD Phenom(tm) II X4 940 Processor
stepping        : 2
microcode       : 0x1000086
cpu MHz         : 2999.912
cache size      : 512 KB
physical id     : 0
siblings        : 4
core id         : 0
cpu cores       : 4
apicid          : 0
initial apicid  : 0
fpu             : yes
fpu_exception   : yes
cpuid level     : 5
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov 
pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb 
rdtscp lm 3dnowext 3dnow constant_tsc rep_good nopl nonstop_tsc extd_apicid pni 
monitor cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a 
misalignsse 3dnowprefetch osvw ibs skinit wdt hw_pstate npt lbrv svm_lock 
nrip_save
bogomips        : 5999.82
TLB size        : 1024 4K pages
clflush size    : 64
cache_alignment : 64
address sizes   : 48 bits physical, 48 bits virtual
power management: ts ttp tm stc 100mhzsteps hwpstate

part of cpuid, CPU 0:
   vendor_id = "AuthenticAMD"
   version information (1/eax):
      processor type  = primary processor (0)
      family          = Intel Pentium 4/Pentium D/Pentium Extreme 
Edition/Celeron/Xeon/Xeon MP/Itanium2, AMD Athlon 64/Athlon 
XP-M/Opteron/Sempron/Turion (15)
      model           = 0x4 (4)
      stepping id     = 0x2 (2)
      extended family = 0x1 (1)
      extended model  = 0x0 (0)
      (simple synth)  = AMD Quad-Core Opteron (Shanghai RB-C2) / Embedded 
Opteron (Shanghai RB-C2) / Athlon Dual-Core (Regor / Propus RB-C2) / Phenom II 
(Callisto / Heka / Deneb RB-C2), 45nm
   miscellaneous (1/ebx):
      process local APIC physical ID = 0x0 (0)
      cpu count                      = 0x4 (4)
      CLFLUSH line size              = 0x8 (8)
      brand index                    = 0x0 (0)
   brand id = 0x00 (0): unknown

Ciao,
Gerhard

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