From: Cyrill Gorcunov <gorcunov@gmail.com>
To: Michal Hocko <mhocko@kernel.org>
Cc: Yang Shi <yang.shi@linux.alibaba.com>,
adobriyan@gmail.com, willy@infradead.org, mguzik@redhat.com,
akpm@linux-foundation.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org
Subject: Re: [v3 PATCH] mm: introduce arg_lock to protect arg_start|end and env_start|end in mm_struct
Date: Tue, 10 Apr 2018 15:28:04 +0300 [thread overview]
Message-ID: <20180410122804.GD2041@uranus.lan> (raw)
In-Reply-To: <20180410111001.GD21835@dhcp22.suse.cz>
On Tue, Apr 10, 2018 at 01:10:01PM +0200, Michal Hocko wrote:
> >
> > Because do_brk does vma manipulations, for this reason it's
> > running under down_write_killable(&mm->mmap_sem). Or you
> > mean something else?
>
> Yes, all we need the new lock for is to get a consistent view on brk
> values. I am simply asking whether there is something fundamentally
> wrong by doing the update inside the new lock while keeping the original
> mmap_sem locking in the brk path. That would allow us to drop the
> mmap_sem lock in the proc path when looking at brk values.
Michal gimme some time. I guess we might do so, but I need some
spare time to take more precise look into the code, hopefully today
evening. Also I've a suspicion that we've wracked check_data_rlimit
with this new lock in prctl. Need to verify it again.
next prev parent reply other threads:[~2018-04-10 12:28 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-04-09 21:52 [v3 PATCH] mm: introduce arg_lock to protect arg_start|end and env_start|end in mm_struct Yang Shi
2018-04-10 8:48 ` Cyrill Gorcunov
2018-04-10 9:09 ` Michal Hocko
2018-04-10 9:40 ` Cyrill Gorcunov
2018-04-10 10:42 ` Michal Hocko
2018-04-10 11:02 ` Cyrill Gorcunov
2018-04-10 11:10 ` Michal Hocko
2018-04-10 12:28 ` Cyrill Gorcunov [this message]
2018-04-10 16:21 ` Yang Shi
2018-04-10 18:28 ` Yang Shi
2018-04-10 19:17 ` Cyrill Gorcunov
2018-04-10 19:33 ` Yang Shi
2018-04-10 20:06 ` Cyrill Gorcunov
2018-04-12 12:18 ` Michal Hocko
2018-04-12 16:20 ` Yang Shi
2018-04-13 6:56 ` 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=20180410122804.GD2041@uranus.lan \
--to=gorcunov@gmail.com \
--cc=adobriyan@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mguzik@redhat.com \
--cc=mhocko@kernel.org \
--cc=willy@infradead.org \
--cc=yang.shi@linux.alibaba.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).