From: Linus Torvalds <torvalds@linux-foundation.org>
To: Mateusz Guzik <mjguzik@gmail.com>
Cc: "Suren Baghdasaryan" <surenb@google.com>,
akpm@linux-foundation.org, regressions@leemhuis.info,
bagasdotme@gmail.com, jacobly.alt@gmail.com, willy@infradead.org,
liam.howlett@oracle.com, david@redhat.com, peterx@redhat.com,
ldufour@linux.ibm.com, linux-kernel@vger.kernel.org,
linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org,
linux-arm-kernel@lists.infradead.org, gregkh@linuxfoundation.org,
regressions@lists.linux.dev, "Jiri Slaby" <jirislaby@kernel.org>,
"Holger Hoffstätte" <holger@applied-asynchrony.com>,
stable@vger.kernel.org
Subject: Re: [PATCH v2 3/3] fork: lock VMAs of the parent process when forking
Date: Fri, 4 Aug 2023 15:49:40 -0700 [thread overview]
Message-ID: <CAHk-=wiy125k1dBmQFTGpHwiOqEyrD6xnd4xKWfe97H_HodgDA@mail.gmail.com> (raw)
In-Reply-To: <20230804214620.btgwhsszsd7rh6nf@f>
On Fri, 4 Aug 2023 at 14:46, Mateusz Guzik <mjguzik@gmail.com> wrote:
>
> I don't see it mentioned in the discussion, so at a risk of ruffling
> feathers or looking really bad I'm going to ask: is the locking of any
> use if the forking process is single-threaded? T
Sadly, we've always been able to access the mm from other processes,
so the locking is - I think - unavoidable.
And some of those "access from other processes" aren't even uncommon
or special. It's things like "ps" etc, that do it just to see the
process name and arguments.
Linus
next prev parent reply other threads:[~2023-08-04 22:50 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-08 19:12 [PATCH v2 1/3] mm: lock a vma before stack expansion Suren Baghdasaryan
2023-07-08 19:12 ` [PATCH v2 2/3] mm: lock newly mapped VMA which can be modified after it becomes visible Suren Baghdasaryan
2023-07-08 19:12 ` [PATCH v2 3/3] fork: lock VMAs of the parent process when forking Suren Baghdasaryan
2023-07-08 19:22 ` Suren Baghdasaryan
2023-07-08 21:18 ` Linus Torvalds
2023-07-08 22:36 ` Suren Baghdasaryan
2023-07-08 22:53 ` Linus Torvalds
2023-07-08 23:03 ` Suren Baghdasaryan
2023-08-04 21:46 ` Mateusz Guzik
2023-08-04 22:49 ` Linus Torvalds [this message]
2023-08-04 23:25 ` Mateusz Guzik
2023-08-05 0:14 ` Linus Torvalds
2023-08-05 0:26 ` Suren Baghdasaryan
2023-08-05 0:34 ` Suren Baghdasaryan
2023-08-05 0:49 ` Mateusz Guzik
2023-08-05 1:06 ` Suren Baghdasaryan
2023-08-05 1:16 ` Mateusz Guzik
2023-08-05 1:36 ` Suren Baghdasaryan
2023-08-05 1:06 ` Mateusz Guzik
2023-08-05 1:42 ` Suren Baghdasaryan
2023-08-09 21:07 ` Mateusz Guzik
2023-08-10 20:31 ` Suren Baghdasaryan
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