Re: [Xen-devel] [PATCH 6/8] x86: (command line option to) avoid use of secondary hyper-threads

2018-07-16 Thread Andrew Cooper
On 16/07/18 13:53, Jan Beulich wrote: On 16.07.18 at 14:37, wrote: >> On 13/07/18 09:13, Jan Beulich wrote: >> On 12.07.18 at 17:45, wrote: On 11/07/18 13:10, Jan Beulich wrote: > --- a/docs/misc/xen-command-line.markdown > +++ b/docs/misc/xen-command-line.markdown > @@

Re: [Xen-devel] [PATCH 6/8] x86: (command line option to) avoid use of secondary hyper-threads

2018-07-16 Thread Jan Beulich
>>> On 16.07.18 at 14:37, wrote: > On 13/07/18 09:13, Jan Beulich wrote: > On 12.07.18 at 17:45, wrote: >>> On 11/07/18 13:10, Jan Beulich wrote: --- a/docs/misc/xen-command-line.markdown +++ b/docs/misc/xen-command-line.markdown @@ -1040,6 +1040,13 @@ identical to the boot

Re: [Xen-devel] [PATCH 6/8] x86: (command line option to) avoid use of secondary hyper-threads

2018-07-16 Thread Andrew Cooper
On 13/07/18 09:13, Jan Beulich wrote: On 12.07.18 at 17:45, wrote: >> On 11/07/18 13:10, Jan Beulich wrote: >>> --- a/docs/misc/xen-command-line.markdown >>> +++ b/docs/misc/xen-command-line.markdown >>> @@ -1040,6 +1040,13 @@ identical to the boot CPU will be parked >>> ### hpetbroadcast

Re: [Xen-devel] [PATCH 6/8] x86: (command line option to) avoid use of secondary hyper-threads

2018-07-13 Thread Jan Beulich
>>> On 12.07.18 at 17:45, wrote: > On 11/07/18 13:10, Jan Beulich wrote: >> --- a/docs/misc/xen-command-line.markdown >> +++ b/docs/misc/xen-command-line.markdown >> @@ -1040,6 +1040,13 @@ identical to the boot CPU will be parked >> ### hpetbroadcast (x86) >> > `= ` >> >> +### ht (x86) > >

Re: [Xen-devel] [PATCH 6/8] x86: (command line option to) avoid use of secondary hyper-threads

2018-07-12 Thread Andrew Cooper
On 11/07/18 13:10, Jan Beulich wrote: > Shared resources (L1 cache and TLB in particular) present a risk of > information leak via side channels. Don't use hyperthreads in such > cases, but allow independent control of their use at the same time. > > Signed-off-by: Jan Beulich > --- > An option