From: Eric Biggers <ebiggers@kernel.org>
To: Hillf Danton <hdanton@sina.com>
Cc: syzbot <syzbot+7a0d9d0b26efefe61780@syzkaller.appspotmail.com>,
akpm@linux-foundation.org, arve@android.com,
christian@brauner.io, devel@driverdev.osuosl.org,
gregkh@linuxfoundation.org, hughd@google.com,
joel@joelfernandes.org, linux-kernel@vger.kernel.org,
linux-mm@kvack.org, maco@android.com,
syzkaller-bugs@googlegroups.com, tkjos@android.com,
Markus Elfring <Markus.Elfring@web.de>
Subject: Re: possible deadlock in shmem_fallocate (4)
Date: Mon, 13 Jul 2020 20:41:11 -0700 [thread overview]
Message-ID: <20200714034111.GD1696@sol.localdomain> (raw)
In-Reply-To: <20200714033252.8748-1-hdanton@sina.com>
On Tue, Jul 14, 2020 at 11:32:52AM +0800, Hillf Danton wrote:
>
> Add FALLOC_FL_NOBLOCK and on the shmem side try to lock inode upon the
> new flag. And the overall upside is to keep the current gfp either in
> the khugepaged context or not.
>
> --- a/include/uapi/linux/falloc.h
> +++ b/include/uapi/linux/falloc.h
> @@ -77,4 +77,6 @@
> */
> #define FALLOC_FL_UNSHARE_RANGE 0x40
>
> +#define FALLOC_FL_NOBLOCK 0x80
> +
You can't add a new UAPI flag to fix a kernel-internal problem like this.
- Eric
next prev parent reply other threads:[~2020-07-14 3:41 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-26 21:25 syzbot
2020-03-07 21:43 ` [ashmem] " Eric Biggers
2020-03-08 15:05 ` Hillf Danton
2020-07-14 0:32 ` syzbot
2020-07-14 3:32 ` Hillf Danton
2020-07-14 3:41 ` Eric Biggers [this message]
2020-07-14 5:32 ` Hillf Danton
2020-07-14 8:26 ` Michal Hocko
2020-07-14 14:08 ` Hillf Danton
2020-07-14 14:18 ` Michal Hocko
2020-07-14 15:46 ` Todd Kjos
2020-07-14 16:41 ` Suren Baghdasaryan
2020-07-14 17:32 ` Suren Baghdasaryan
2020-07-15 3:52 ` Hillf Danton
2020-07-15 6:36 ` Michal Hocko
2020-07-16 2:49 ` Suren Baghdasaryan
2020-07-14 3:07 ` syzbot
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=20200714034111.GD1696@sol.localdomain \
--to=ebiggers@kernel.org \
--cc=Markus.Elfring@web.de \
--cc=akpm@linux-foundation.org \
--cc=arve@android.com \
--cc=christian@brauner.io \
--cc=devel@driverdev.osuosl.org \
--cc=gregkh@linuxfoundation.org \
--cc=hdanton@sina.com \
--cc=hughd@google.com \
--cc=joel@joelfernandes.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=maco@android.com \
--cc=syzbot+7a0d9d0b26efefe61780@syzkaller.appspotmail.com \
--cc=syzkaller-bugs@googlegroups.com \
--cc=tkjos@android.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