linux-kernel - Re: [PATCH v5 00/25] context_tracking,x86: Defer some IPIs until a user->kernel transition

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Message-ID: <20250430132047.01d48647@gandalf.local.home>
Date: Wed, 30 Apr 2025 13:20:47 -0400
From: Steven Rostedt <rostedt@...dmis.org>
To: Dave Hansen <dave.hansen@...el.com>
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Subject: Re: [PATCH v5 00/25] context_tracking,x86: Defer some IPIs until a
 user->kernel transition

On Tue, 29 Apr 2025 09:11:57 -0700
Dave Hansen <dave.hansen@...el.com> wrote:

> I don't think we should do this series.

Could you provide more rationale for your decision.

> 
> If folks want this functionality, they should get a new CPU that can
> flush the TLB without IPIs.

That's a pretty heavy handed response. I'm not sure that's always a
feasible solution.

From my experience in the world, software has always been around to fix the
hardware, not the other way around ;-)

-- Steve