Re: [PATCH 4/5] KVM: x86: RSI/RDI/RCX are zero-extended when affected by string ops

2014-04-23 Thread Marcelo Tosatti
On Tue, Apr 22, 2014 at 09:04:45AM +0300, Nadav Amit wrote: Gleb, On 4/20/14, 12:26 PM, Gleb Natapov wrote: On Fri, Apr 18, 2014 at 07:11:33AM +0300, Nadav Amit wrote: When using address-size override prefix with string instructions in long-mode, ESI/EDI/ECX are zero extended if they are

Re: [PATCH 4/5] KVM: x86: RSI/RDI/RCX are zero-extended when affected by string ops

2014-04-23 Thread Marcelo Tosatti
On Wed, Apr 23, 2014 at 04:58:32PM -0300, Marcelo Tosatti wrote: On Tue, Apr 22, 2014 at 09:04:45AM +0300, Nadav Amit wrote: Gleb, On 4/20/14, 12:26 PM, Gleb Natapov wrote: On Fri, Apr 18, 2014 at 07:11:33AM +0300, Nadav Amit wrote: When using address-size override prefix with string

Re: [PATCH 4/5] KVM: x86: RSI/RDI/RCX are zero-extended when affected by string ops

2014-04-23 Thread Nadav Amit
On 4/23/14, 11:11 PM, Marcelo Tosatti wrote: On Wed, Apr 23, 2014 at 04:58:32PM -0300, Marcelo Tosatti wrote: On Tue, Apr 22, 2014 at 09:04:45AM +0300, Nadav Amit wrote: Gleb, On 4/20/14, 12:26 PM, Gleb Natapov wrote: On Fri, Apr 18, 2014 at 07:11:33AM +0300, Nadav Amit wrote: When using

Re: [PATCH 4/5] KVM: x86: RSI/RDI/RCX are zero-extended when affected by string ops

2014-04-23 Thread H. Peter Anvin
On 04/23/2014 01:53 PM, Nadav Amit wrote: Err, operand size is forced to 64-bits, not address size. The following aspects of near branches are controlled by the effective operand size: • Truncation of the size of the instruction pointer Still, 67h call should not truncate EIP (which your

Re: [PATCH 4/5] KVM: x86: RSI/RDI/RCX are zero-extended when affected by string ops

2014-04-22 Thread Nadav Amit
Gleb, On 4/20/14, 12:26 PM, Gleb Natapov wrote: On Fri, Apr 18, 2014 at 07:11:33AM +0300, Nadav Amit wrote: When using address-size override prefix with string instructions in long-mode, ESI/EDI/ECX are zero extended if they are affected by the instruction (incremented/decremented).

Re: [PATCH 4/5] KVM: x86: RSI/RDI/RCX are zero-extended when affected by string ops

2014-04-20 Thread Gleb Natapov
On Fri, Apr 18, 2014 at 07:11:33AM +0300, Nadav Amit wrote: When using address-size override prefix with string instructions in long-mode, ESI/EDI/ECX are zero extended if they are affected by the instruction (incremented/decremented). Currently, the KVM emulator does not do so. In