From: Simon Ser <contact@emersion.fr>
To: Matthew Wilcox <willy@infradead.org>
Cc: Hugh Dickins <hughd@google.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
"Lin, Ming" <minggr@gmail.com>, Peter Xu <peterx@redhat.com>,
"Kirill A. Shutemov" <kirill@shutemov.name>,
Dan Williams <dan.j.williams@intel.com>,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
Will Deacon <will@kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
David Herrmann <dh.herrmann@gmail.com>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
Greg Kroah-Hartman <greg@kroah.com>,
"tytso@mit.edu" <tytso@mit.edu>
Subject: Re: Sealed memfd & no-fault mmap
Date: Thu, 03 Jun 2021 14:48:11 +0000 [thread overview]
Message-ID: <yK5pBcI8tfOfgvVkLrLRMaAdSrt7uL8Ppc05GLMMl8JEfBVsY7f-ksJME4RsNJUvOif2u_r_dBh_PwXyPwYl4Ug2tiMiMxVJb7ESHKNS6w4=@emersion.fr> (raw)
In-Reply-To: <YLjf1Hmrkfwc5xUW@casper.infradead.org>
On Thursday, June 3rd, 2021 at 3:57 PM, Matthew Wilcox <willy@infradead.org> wrote:
> How about this:
>
> - The client sets up a 1KiB shm file and sends it to the compositor.
> - The client expands the file to 5KiB
> - The compositor sees the new data up to 4KiB but zeroes past the 4KiB
> mark.
>
> Does that still make userspace happy?
As long as the new data in the expanded region is visible after a remapping the
file with the new size, it should be fine. It doesn't matter that it's not
visible without a munmap+mmap cycle.
prev parent reply other threads:[~2021-06-03 14:48 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-27 8:24 Sealed memfd & no-fault mmap Simon Ser
2021-04-27 16:51 ` Linus Torvalds
2021-04-27 16:51 ` Linus Torvalds
2021-04-29 15:48 ` Kirill A. Shutemov
2021-04-29 18:38 ` Peter Xu
2021-05-04 9:29 ` Simon Ser
2021-05-04 16:08 ` Linus Torvalds
2021-05-04 16:08 ` Linus Torvalds
2021-05-05 10:21 ` Simon Ser
2021-05-05 18:42 ` Linus Torvalds
2021-05-05 18:42 ` Linus Torvalds
2021-05-28 17:07 ` Lin, Ming
2021-05-29 1:03 ` Linus Torvalds
2021-05-29 1:03 ` Linus Torvalds
2021-05-29 7:31 ` Lin, Ming
2021-05-29 15:44 ` Linus Torvalds
2021-05-29 15:44 ` Linus Torvalds
2021-05-29 20:15 ` Hugh Dickins
2021-05-29 20:15 ` Hugh Dickins
2021-05-29 23:36 ` Ming Lin
2021-05-31 21:13 ` Ming Lin
2021-06-01 6:24 ` Linus Torvalds
2021-06-01 6:24 ` Linus Torvalds
2021-06-01 7:08 ` Ming Lin
2021-06-03 13:01 ` Simon Ser
2021-06-03 20:07 ` Ming Lin
2021-06-03 20:49 ` Simon Ser
2021-06-03 13:14 ` Simon Ser
2021-06-03 13:57 ` Matthew Wilcox
2021-06-03 14:48 ` Simon Ser [this message]
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