Re: [Patch v3 04/13] x86/speculation: Disable STIBP when enhanced IBRS is in use

2018-10-26 Thread Tim Chen
On 10/26/2018 11:18 AM, Tim Chen wrote: > On 10/26/2018 10:00 AM, Waiman Long wrote: >> On 10/17/2018 01:59 PM, Tim Chen wrote: >>> With enhanced IBRS in use, the application running on sibling CPU will not >>> be able to launch Spectre v2 attack to the application on current CPU. >>> There is no

Re: [Patch v3 04/13] x86/speculation: Disable STIBP when enhanced IBRS is in use

2018-10-26 Thread Tim Chen
On 10/26/2018 11:18 AM, Tim Chen wrote: > On 10/26/2018 10:00 AM, Waiman Long wrote: >> On 10/17/2018 01:59 PM, Tim Chen wrote: >>> With enhanced IBRS in use, the application running on sibling CPU will not >>> be able to launch Spectre v2 attack to the application on current CPU. >>> There is no

Re: [Patch v3 04/13] x86/speculation: Disable STIBP when enhanced IBRS is in use

2018-10-26 Thread Tim Chen
On 10/26/2018 10:00 AM, Waiman Long wrote: > On 10/17/2018 01:59 PM, Tim Chen wrote: >> With enhanced IBRS in use, the application running on sibling CPU will not >> be able to launch Spectre v2 attack to the application on current CPU. >> There is no need to use STIBP for this case. Disable the

Re: [Patch v3 04/13] x86/speculation: Disable STIBP when enhanced IBRS is in use

2018-10-26 Thread Tim Chen
On 10/26/2018 10:00 AM, Waiman Long wrote: > On 10/17/2018 01:59 PM, Tim Chen wrote: >> With enhanced IBRS in use, the application running on sibling CPU will not >> be able to launch Spectre v2 attack to the application on current CPU. >> There is no need to use STIBP for this case. Disable the

Re: [Patch v3 04/13] x86/speculation: Disable STIBP when enhanced IBRS is in use

2018-10-26 Thread Waiman Long
On 10/17/2018 01:59 PM, Tim Chen wrote: > With enhanced IBRS in use, the application running on sibling CPU will not > be able to launch Spectre v2 attack to the application on current CPU. > There is no need to use STIBP for this case. Disable the STIBP code > when enhanced IBRS is used. > >

Re: [Patch v3 04/13] x86/speculation: Disable STIBP when enhanced IBRS is in use

2018-10-26 Thread Waiman Long
On 10/17/2018 01:59 PM, Tim Chen wrote: > With enhanced IBRS in use, the application running on sibling CPU will not > be able to launch Spectre v2 attack to the application on current CPU. > There is no need to use STIBP for this case. Disable the STIBP code > when enhanced IBRS is used. > >

Re: [Patch v3 04/13] x86/speculation: Disable STIBP when enhanced IBRS is in use

2018-10-18 Thread Thomas Gleixner
On Wed, 17 Oct 2018, Tim Chen wrote: > With enhanced IBRS in use, the application running on sibling CPU will not on a hyperthread sibling > be able to launch Spectre v2 attack to the application on current CPU. That's technically wrong. It still can launch an attack, but the attack wont

Re: [Patch v3 04/13] x86/speculation: Disable STIBP when enhanced IBRS is in use

2018-10-18 Thread Thomas Gleixner
On Wed, 17 Oct 2018, Tim Chen wrote: > With enhanced IBRS in use, the application running on sibling CPU will not on a hyperthread sibling > be able to launch Spectre v2 attack to the application on current CPU. That's technically wrong. It still can launch an attack, but the attack wont

[Patch v3 04/13] x86/speculation: Disable STIBP when enhanced IBRS is in use

2018-10-17 Thread Tim Chen
With enhanced IBRS in use, the application running on sibling CPU will not be able to launch Spectre v2 attack to the application on current CPU. There is no need to use STIBP for this case. Disable the STIBP code when enhanced IBRS is used. Signed-off-by: Tim Chen ---

[Patch v3 04/13] x86/speculation: Disable STIBP when enhanced IBRS is in use

2018-10-17 Thread Tim Chen
With enhanced IBRS in use, the application running on sibling CPU will not be able to launch Spectre v2 attack to the application on current CPU. There is no need to use STIBP for this case. Disable the STIBP code when enhanced IBRS is used. Signed-off-by: Tim Chen ---