The following reply was made to PR port-xen/34005; it has been noted by GNATS.

From: Manuel Bouyer <bouyer@antioche.eu.org>
To: YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
Cc: gnats-bugs@NetBSD.org, port-xen-maintainer@NetBSD.org,
	gnats-admin@NetBSD.org, netbsd-bugs@NetBSD.org
Subject: Re: port-xen/34005: xen3 loses bio requests?
Date: Mon, 16 Oct 2006 13:29:49 +0200

 On Mon, Oct 16, 2006 at 08:16:23PM +0900, YAMAMOTO Takashi wrote:
 > > On Mon, Oct 16, 2006 at 10:43:33AM +0900, YAMAMOTO Takashi wrote:
 > > > i don't think it can fix the problem for me as it's a single cpu machine.
 > > 
 > > What kind of CPU is it ? It's strange that I've never noticed the problem
 > > myself ...
 > 
 > vcpu0 at hypervisor0: (uniprocessor)
 > vcpu0: Intel Pentium III (686-class), 696.97 MHz, id 0x68a
 > vcpu0: features 383f9ff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,SEP,MTRR>
 > vcpu0: features 383f9ff<PGE,MCA,CMOV,PAT,PSE36,MMX>
 > vcpu0: features 383f9ff<FXSR,SSE>
 > vcpu0: I-cache 16 KB 32B/line 4-way, D-cache 16 KB 32B/line 4-way
 > vcpu0: L2 cache 256 KB 32B/line 8-way
 > vcpu0: ITLB 32 4 KB entries 4-way, 2 4 MB entries fully associative
 > vcpu0: DTLB 64 4 KB entries 4-way, 8 4 MB entries 4-way
 > vcpu0: 8 page colors
 
 Well, my test system is a PII:
 vcpu0: Intel Pentium II (686-class), 400.91 MHz, id 0x652
 vcpu0: features 183fbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR>
 vcpu0: features 183fbff<PGE,MCA,CMOV,PAT,PSE36,MMX>
 vcpu0: features 183fbff<FXSR>
 
 Mine doens't have SSE. sfence was added with SSE; so memory writes have
 probably different behaviors between PII and PIII. But for this to matters
 on a UP system we would need a different set of write buffers for
 ring0 and ring1, and AFAIK this is not the case.
 
 -- 
 Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
      NetBSD: 26 ans d'experience feront toujours la difference
 --