Re: [PATCH v2 4/8] x86: Initial support for WRMSRNS

2023-01-16 Thread Andrew Cooper
On 12/01/2023 3:11 pm, Jan Beulich wrote: > On 12.01.2023 14:58, Andrew Cooper wrote: >> On 12/01/2023 12:58 pm, Jan Beulich wrote: >>> Do you have any indications towards a CS prefix being the least risky >>> one to use here (or in general)? >> Yes. >> >> Remember it's the prefix recommended for,

Re: [PATCH v2 4/8] x86: Initial support for WRMSRNS

2023-01-12 Thread Jan Beulich
On 12.01.2023 14:58, Andrew Cooper wrote: > On 12/01/2023 12:58 pm, Jan Beulich wrote: >> Do you have any indications towards a CS prefix being the least risky >> one to use here (or in general)? > > Yes. > > Remember it's the prefix recommended for, and used by, > -mbranches-within-32B-boundarie

Re: [PATCH v2 4/8] x86: Initial support for WRMSRNS

2023-01-12 Thread Andrew Cooper
On 12/01/2023 12:58 pm, Jan Beulich wrote: > On 10.01.2023 18:18, Andrew Cooper wrote: >> WRMSR Non-Serialising is an optimisation intended for cases where an MSR >> needs >> updating, but architectural serialising properties are not needed. >> >> In is anticipated that this will apply to most if

Re: [PATCH v2 4/8] x86: Initial support for WRMSRNS

2023-01-12 Thread Jan Beulich
On 10.01.2023 18:18, Andrew Cooper wrote: > WRMSR Non-Serialising is an optimisation intended for cases where an MSR needs > updating, but architectural serialising properties are not needed. > > In is anticipated that this will apply to most if not all MSRs modified on > context switch paths. >

[PATCH v2 4/8] x86: Initial support for WRMSRNS

2023-01-10 Thread Andrew Cooper
WRMSR Non-Serialising is an optimisation intended for cases where an MSR needs updating, but architectural serialising properties are not needed. In is anticipated that this will apply to most if not all MSRs modified on context switch paths. Signed-off-by: Andrew Cooper --- CC: Jan Beulich CC: