Re: [PATCH v6] x86/mm: Don't disable INVLPG if "incomplete Global INVLPG flushes" is fixed by microcode or the kernel is running in a hypervisor

From: Dave Hansen
Date: Thu Apr 11 2024 - 11:20:42 EST


On 4/11/24 07:48, Xi Ruoyao wrote:
> On Thu, 2024-04-11 at 07:44 -0700, Dave Hansen wrote:
>> On 4/11/24 03:48, Xi Ruoyao wrote:
>>> + /*
>>> + * The Intel errata claims: "this erratum does not apply in VMX
>>> + * non-root operation.  It applies only when PCIDs are enabled
>>> + * and either in VMX root operation or outside VMX operation."
>>> + * So we are safe if we are surely running in a hypervisor.
>>> + */
>> When you revise this, could you please work to make this more succinct?
>> The Intel language on these things tends to be a bit flowery and is not
>> always well-suited for the kernel.
> Oops, bad timing. I just sent v7 before getting this reply.

One way to avoid bad timing like this is to wait more than 4 hours
between patch revisions.

> I'm not a native English speaker, so could you give some hint about how
> to write this comment clearly?

Something like this would be fine:

/* Only bare-metal is affected. PCIDs in guests are OK. */