From: "H. Peter Anvin" <hpa@zytor.com>
To: Kay Sievers <kay@vrfy.org>
Cc: John Stultz <john.stultz@linaro.org>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
Greg KH <gregkh@linuxfoundation.org>,
Android Kernel Team <kernel-team@android.com>,
Andrew Morton <akpm@linux-foundation.org>,
Mel Gorman <mgorman@suse.de>, Hugh Dickins <hughd@google.com>,
Dave Hansen <dave.hansen@intel.com>,
Rik van Riel <riel@redhat.com>,
Michel Lespinasse <walken@google.com>,
Johannes Weiner <hannes@cmpxchg.org>, Neil Brown <neilb@suse.de>,
Andrea Arcangeli <aarcange@redhat.com>,
Takahiro Akashi <takahiro.akashi@linaro.org>,
Minchan Kim <minchan@kernel.org>,
Lennart Poettering <mzxreary@0pointer.de>
Subject: Re: [RFC] shmgetfd idea
Date: Tue, 28 Jan 2014 16:20:17 -0800 [thread overview]
Message-ID: <52E84941.4080704@zytor.com> (raw)
In-Reply-To: <CAPXgP13u+0PCFsRDRFqSdopDuXyAvZCS2crOCDrPoT6m8Nq2Og@mail.gmail.com>
On 01/28/2014 04:14 PM, Kay Sievers wrote:
>>
>> If the "single owner" is determined by the file structure (e.g. via a
>> fcntl as opposed to a ioctl), then presumably we would simply deny an
>> attempt to open the inode and create a new file structure for it.
>>
>> On Linux, /proc/$PID/fd is an open as opposed to a dup (as much as I
>> personally don't like those semantics, they are well set in stone at
>> this point) so it satisfies your requirements.
>
> If that all could be made working, for the kdbus case we would be fine
> with requiring *any* tmpfs mount, create a new memfd from there with
> O_TMPFILE, and use new fcntl() definitios to protect/seal/unseal and
> identify that fd.
>
> For the more restricted cases like Android that tmpfs mount could get
> a mount option to not allow the creation of any non-unlinked file, I
> guess.
>
Right, that would be the idea.
-hpa
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2014-01-29 0:20 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-01-28 1:37 [RFC] shmgetfd idea John Stultz
2014-01-28 1:53 ` Kay Sievers
2014-01-28 19:47 ` John Stultz
2014-01-28 3:52 ` H. Peter Anvin
2014-01-28 19:56 ` John Stultz
2014-01-28 20:37 ` H. Peter Anvin
2014-01-28 20:58 ` John Stultz
2014-01-28 21:01 ` Kay Sievers
2014-01-28 21:05 ` John Stultz
2014-01-28 21:10 ` H. Peter Anvin
2014-01-28 21:54 ` John Stultz
2014-01-28 22:14 ` Kay Sievers
2014-01-28 23:02 ` H. Peter Anvin
2014-01-28 23:14 ` Kay Sievers
2014-01-28 23:19 ` H. Peter Anvin
2014-01-29 0:14 ` Kay Sievers
2014-01-29 0:20 ` H. Peter Anvin [this message]
2014-01-29 0:49 ` Kay Sievers
2014-01-28 23:14 ` John Stultz
2014-01-28 21:28 ` Kay Sievers
2014-01-30 8:46 ` Christoph Hellwig
2014-01-30 16:02 ` Kay Sievers
2014-01-30 21:42 ` John Stultz
2014-01-31 0:01 ` Kay Sievers
2014-02-03 15:03 ` Christoph Hellwig
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=52E84941.4080704@zytor.com \
--to=hpa@zytor.com \
--cc=aarcange@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=dave.hansen@intel.com \
--cc=gregkh@linuxfoundation.org \
--cc=hannes@cmpxchg.org \
--cc=hughd@google.com \
--cc=john.stultz@linaro.org \
--cc=kay@vrfy.org \
--cc=kernel-team@android.com \
--cc=linux-mm@kvack.org \
--cc=mgorman@suse.de \
--cc=minchan@kernel.org \
--cc=mzxreary@0pointer.de \
--cc=neilb@suse.de \
--cc=riel@redhat.com \
--cc=takahiro.akashi@linaro.org \
--cc=walken@google.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;
as well as URLs for NNTP newsgroup(s).