From mboxrd@z Thu Jan  1 00:00:00 1970
From: Razvan Cojocaru <rcojocaru@bitdefender.com>
Subject: Re: Failed vm entry with heavy use of emulator
Date: Tue, 5 Jan 2016 16:01:57 +0200
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To: Andrew Cooper <andrew.cooper3@citrix.com>, xen-devel@lists.xen.org, Tamas Lengyel <tamas.k.lengyel@gmail.com>
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On 01/05/2016 03:49 PM, Andrew Cooper wrote:
> On 05/01/16 13:39, Razvan Cojocaru wrote:
>> Here's a quick log of the emulated instructions on my setup:
>> http://pastebin.com/raw/XXQ0Lnzh
> 
> Hmm - according to that, the final instruction emulated was
> 
> d1v0 32bit @ 0008:828925db -> fa
> 
> which is the 'cli' instruction.
> 
> I would start there - I doubt it is an instruction which is emulated often.

My code (arch/x86/x86_emulate/x86_emulate.c) does have a case label for it:

3677     case 0xfa: /* cli */
3678         generate_exception_if(!mode_iopl(), EXC_GP, 0);
3679         _regs.eflags &= ~EFLG_IF;
3680         break;

Maybe the IOPL test fails there? Tamas, does your guest die after a CLI
as well?


Thanks,
Razvan