Re: [Xen-devel] [PATCH v11 7/11] x86/entry: Avoid using alternatives in NMI/#MC paths

2018-01-26 Thread Andrew Cooper
On 26/01/18 12:23, Jan Beulich wrote: On 25.01.18 at 18:21, wrote: >> This patch is deliberately arranged to be easy to revert if/when alternatives >> patching becomes NMI/#MC safe. >> >> For safety, there must be a dispatch serialising instruction in (what is >>

Re: [Xen-devel] [PATCH v11 7/11] x86/entry: Avoid using alternatives in NMI/#MC paths

2018-01-26 Thread Jan Beulich
>>> On 25.01.18 at 18:21, wrote: > This patch is deliberately arranged to be easy to revert if/when alternatives > patching becomes NMI/#MC safe. > > For safety, there must be a dispatch serialising instruction in (what is > logically) DO_SPEC_CTRL_ENTRY so that, in