Re: [Xen-devel] [PATCH v2 0/7] x86: Meltdown band-aid overhead reduction

2018-02-14 Thread Jan Beulich
>>> On 13.02.18 at 19:39, wrote: > On Feb 7, 2018, at 11:05, Jan Beulich wrote: >> >> 1: slightly reduce Meltdown band-aid overhead >> 2: remove CR reads from exit-to-guest path >> 3: introduce altinstruction_nop assembler macro >> 4: NOP out most XPTI

Re: [Xen-devel] [PATCH v2 0/7] x86: Meltdown band-aid overhead reduction

2018-02-13 Thread Rich Persaud
On Feb 7, 2018, at 11:05, Jan Beulich wrote: > > 1: slightly reduce Meltdown band-aid overhead > 2: remove CR reads from exit-to-guest path > 3: introduce altinstruction_nop assembler macro > 4: NOP out most XPTI entry/exit code when it's not in use > 5: avoid double CR3

[Xen-devel] [PATCH v2 0/7] x86: Meltdown band-aid overhead reduction

2018-02-07 Thread Jan Beulich
1: slightly reduce Meltdown band-aid overhead 2: remove CR reads from exit-to-guest path 3: introduce altinstruction_nop assembler macro 4: NOP out most XPTI entry/exit code when it's not in use 5: avoid double CR3 reload when switching to guest user mode 6: disable XPTI when RDCL_NO 7: x86: log