From: Mel Gorman <mgorman@techsingularity.net>
To: yong w <yongw.pur@gmail.com>
Cc: wuzhouhui <wuzhouhui14@mails.ucas.ac.cn>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
akpm@linux-foundation.org, nico@fluxnic.net,
wang.yong12@zte.com.cn
Subject: Re: Re: [BUG] ramfs system panic when using dd to create files
Date: Thu, 15 Jul 2021 12:44:24 +0100 [thread overview]
Message-ID: <20210715114424.GR3809@techsingularity.net> (raw)
In-Reply-To: <CAOH5QeCV3c-=RiwGrUn7214NRZye7wYFmPSyFWxw-0Zvk=j2GQ@mail.gmail.com>
On Wed, Jul 14, 2021 at 10:30:22PM +0800, yong w wrote:
> Thanks for your reply!
>
> > Limit max size of ramfs.
> It's no use using size to limit the size of ramfs.
> "mount -t ramfs -o size=10M ramfs /ramfs" is the command i use.
>
ramfs does not support size= limiting, that's what tmpfs is for.
> >
> > The comments already explains why kernel should panic on this situation:
> > /*
> > * If we got here due to an actual allocation at the
> > * system level, we cannot survive this and will enter
> > * an endless loop in the allocator. Bail out now.
> > */
>
> But it causes panic, actually , I don't want it panics
Then use tmpfs and specify size=. It's mentioned in filesystems/tmpfs.rst
--8<--
If you compare it to ramfs (which was the template to create tmpfs)
you gain swapping and limit checking. Another similar thing is the RAM
disk (/dev/ram*), which simulates a fixed size hard disk in physical
RAM, where you have to create an ordinary filesystem on top. Ramdisks
cannot swap and you do not have the possibility to resize them.
--8<--
--
Mel Gorman
SUSE Labs
next prev parent reply other threads:[~2021-07-15 11:44 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-07 9:58 yong w
2021-07-14 0:24 ` yong w
2021-07-14 7:35 ` wuzhouhui
2021-07-14 14:30 ` yong w
2021-07-15 11:44 ` Mel Gorman [this message]
2021-07-14 14:36 ` Michal Hocko
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210715114424.GR3809@techsingularity.net \
--to=mgorman@techsingularity.net \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=nico@fluxnic.net \
--cc=wang.yong12@zte.com.cn \
--cc=wuzhouhui14@mails.ucas.ac.cn \
--cc=yongw.pur@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox