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Date:   Sun, 26 Jul 2020 23:20:41 -0700
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Subject: Re: [PATCH 18/23] init: open code setting up stdin/stdout/stderr
To:     Al Viro <viro@zeniv.linux.org.uk>, Christoph Hellwig <hch@lst.de>
CC:     linux-kernel@vger.kernel.org, Song Liu <song@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-raid@vger.kernel.org, linux-fsdevel@vger.kernel.org
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On July 26, 2020 8:05:34 PM PDT, Al Viro <viro@zeniv=2Elinux=2Eorg=2Euk> wr=
ote:
>On Tue, Jul 14, 2020 at 09:04:22PM +0200, Christoph Hellwig wrote:
>> Don't rely on the implicit set_fs(KERNEL_DS) for ksys_open to work,
>but
>> instead open a struct file for /dev/console and then install it as FD
>> 0/1/2 manually=2E
>
>I really hate that one=2E  Every time we exposed the internal details to
>the fucking early init code, we paid for that afterwards=2E  And this
>goes over the top wrt the level of details being exposed=2E
>
>_IF_ you want to keep that thing, move it to fs/file=2Ec, with dire
>comment
>re that being very special shite for init and likely cause of
>subsequent
>trouble whenever anything gets changed, a gnat farts somewhere, etc=2E
>
>	Do not leave that kind of crap sitting around init/*=2Ec; KERNEL_DS
>may be a source of occasional PITA, but here you are trading it for a
>lot
>worse one in the future=2E

Okay=2E=2E=2E here is a perhaps idiotic idea=2E=2E=2E even if we don't wan=
t to run stuff in actual user space, could we map initramfs into user space=
 memory before running init (execing init will tear down those mappings any=
way) so that we don't need KERNEL_DS at least?
--=20
Sent from my Android device with K-9 Mail=2E Please excuse my brevity=2E