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From: Christoph Hellwig <hch@infradead.org>
To: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Christoph Hellwig <hch@infradead.org>,
	michael@michaelkloos.com,
	Paul Walmsley <paul.walmsley@sifive.com>,
	aou@eecs.berkeley.edu, linux-riscv@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] riscv: Work to remove kernel dependence on the M-extension
Date: Thu, 10 Mar 2022 00:04:50 -0800	[thread overview]
Message-ID: <YimxItxjPsPTXeub@infradead.org> (raw)
In-Reply-To: <mhng-08a28047-b563-41f4-b705-f27b88554f2c@palmer-mbp2014>

On Wed, Mar 09, 2022 at 11:34:25PM -0800, Palmer Dabbelt wrote:
> If someone has hardware that lacks M and users care about running Linux on
> that then I'm happy to support it.  I'll still point out the silliness of
> that decision, but if it's too late to change things then I'd rather support
> the hardware.  If it's one of these "fill out every possible allowed ISA
> flavor, even if nobody has one that runs Linux" then I don't see a reason to
> bother -- there's an infinite amount of allowable RISC-V implementations,
> we'll all go crazy chasing them around.

It's not like Linux had required M mode since the RISC-V port was merged
upstream, so any new implementor really should know about it.  And
performance on anything that requires Linux will just be horrible.
I could see a bit of an excuse for a nommu port.

Anyway, this kind of patch really does need to state the why.  And it
better be a really good reason.

  reply	other threads:[~2022-03-10  8:05 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-03-09  5:28 [PATCH] riscv: Work to remove kernel dependence on the M-extension Michael T. Kloos
2022-03-09 10:02 ` Arnd Bergmann
2022-03-09 11:43   ` Michael T. Kloos
2022-03-09 11:47     ` Arnd Bergmann
2022-03-10  7:34   ` Palmer Dabbelt
2022-03-10  7:54     ` Arnd Bergmann
2022-03-10 17:09       ` Palmer Dabbelt
2022-04-02 10:18         ` Pavel Machek
2022-03-10  7:06 ` Christoph Hellwig
2022-03-10  7:34   ` Palmer Dabbelt
2022-03-10  8:04     ` Christoph Hellwig [this message]
2022-03-10  9:31     ` Michael T. Kloos
2022-03-10 13:22       ` Michael T. Kloos
2022-03-10 13:37         ` Michael T. Kloos
2022-03-11  4:29           ` Palmer Dabbelt
2022-03-11  4:54             ` Michael T. Kloos

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